From 6cb886b6efc921509b8f43b5d65abe36e81444d2 Mon Sep 17 00:00:00 2001
From: ankatta <anilreddykatta@hotmail.com>
Date: Thu, 22 Jun 2017 15:38:32 -0700
Subject: [PATCH] Consistent naming of files

---
 .../__tests__/{user-test.js => user.test.js}  |  0
 ...el-test.js => checkbox_with_label.test.js} |  0
 ...splayUser-test.js => display_user.test.js} |  0
 ...ser-test.js => fetch_current_user.test.js} |  0
 ...arizer-test.js => file_summarizer.test.js} |  0
 ...{Intro-test.js.snap => intro.test.js.snap} |  0
 .../{Intro-test.js => intro.test.js}          |  0
 ...el-test.js => checkbox_with_label.test.js} |  0
 ...-test.js.snap => clock.react.test.js.snap} |  0
 ...t-test.js.snap => link.react.test.js.snap} |  0
 ...lock.react-test.js => clock.react.test.js} |  0
 ...{Link.react-test.js => link.react.test.js} |  0
 ...me-test.js => infinite_timer_game.test.js} |  0
 .../{timerGame-test.js => timer_game.test.js} |  0
 ...-test.tsx => checkbox_with_label.test.tsx} |  0
 .../__tests__/{sum-test.js => sum.test.js}    |  0
 ...sole-test.js.snap => console.test.js.snap} | 22 +++----
 ...s.snap => coverage_remapping.test.js.snap} |  0
 ...t.js.snap => coverage_report.test.js.snap} |  0
 ...s.snap => coverage_threshold.test.js.snap} |  0
 ....js.snap => custom_reporters.test.js.snap} | 28 ++++----
 ...res-test.js.snap => failures.test.js.snap} | 44 ++++++-------
 ...bals-test.js.snap => globals.test.js.snap} | 14 ++--
 ...st.js.snap => jest.config.js.test.js.snap} |  0
 ...-test.js.snap => show_config.test.js.snap} |  0
 ...hot-test.js.snap => snapshot.test.js.snap} | 14 ++--
 ...snap => snapshot_serializers.test.js.snap} |  0
 ...-test.js.snap => stack_trace.test.js.snap} | 14 ++--
 ...js.snap => test_name_pattern.test.js.snap} |  0
 ...uts-test.js.snap => timeouts.test.js.snap} |  0
 ...rm-test.js.snap => transform.test.js.snap} |  0
 ....snap => typescript_coverage.test.js.snap} |  0
 ...mocks-test.js => auto_clear_mocks.test.js} |  0
 ...mocks-test.js => auto_reset_mocks.test.js} |  0
 ...est.js => babel_plugin_jest_hoist.test.js} |  0
 ...odes-test.js => compare_dom_nodes.test.js} |  0
 .../{config-test.js => config.test.js}        |  0
 .../{console-test.js => console.test.js}      |  0
 ...ing-test.js => coverage_remapping.test.js} |  0
 ...report-test.js => coverage_report.test.js} |  2 +-
 ...old-test.js => coverage_threshold.test.js} |  0
 ...rters-test.js => custom_reporters.test.js} | 25 +++----
 .../{debug-test.js => debug.test.js}          |  0
 ...rror-test.js => empty_suite_error.test.js} |  0
 .../__tests__/{env-test.js => env.test.js}    |  0
 .../{failures-test.js => failures.test.js}    | 10 +--
 .../{global-test.js => global.test.js}        |  0
 .../{globals-test.js => globals.test.js}      | 16 ++---
 ...ne_async-test.js => jasmine_async.test.js} | 22 ++++---
 ...nfig.js-test.js => jest.config.js.test.js} |  0
 .../__tests__/{json-test.js => json.test.js}  |  0
 ...reporter-test.js => json_reporter.test.js} |  0
 ...{list_tests-test.js => list_tests.test.js} |  0
 ...mock-test.js => native_async_mock.test.js} |  0
 ...st-found-test.js => no_test_found.test.js} |  0
 .../{node_path-test.js => node_path.test.js}  |  0
 ...th-test.js => regex_(char_in_path.test.js} |  0
 ...dule-test.js => require_v8_module.test.js} |  0
 .../{resolve-test.js => resolve.test.js}      |  0
 ... runtime_internal_module_registry.test.js} |  0
 ...mmediate-test.js => set_immediate.test.js} |  0
 ..._framework_script_file_cli_config.test.js} |  6 +-
 ...showConfig-test.js => show_config.test.js} |  0
 .../{snapshot-test.js => snapshot.test.js}    | 30 ++++-----
 ...s-test.js => snapshot_serializers.test.js} |  2 +-
 ...tack_trace-test.js => stack_trace.test.js} | 30 ++++-----
 .../{symbol-test.js => symbol.test.js}        |  0
 ...nment-test.js => test_environment.test.js} |  0
 ...t-in-root-test.js => test_in_root.test.js} |  0
 ...tern-test.js => test_name_pattern.test.js} |  0
 ...test.js => test_results_processor.test.js} |  0
 .../{timeouts-test.js => timeouts.test.js}    |  0
 ...ocks-test.js => timer_reset_mocks.test.js} |  0
 ...-test.js => timer_use_real_timers.test.js} |  2 +-
 ...shot-test.js => to_match_snapshot.test.js} | 12 ++--
 ... to_throw_error_matching_snapshot.test.js} |  8 +--
 .../{transform-test.js => transform.test.js}  |  8 +--
 ...ge-test.js => typescript_coverage.test.js} |  0
 .../{verbose-test.js => verbose.test.js}      |  0
 ...ntegration-test.js => integration.test.js} |  0
 ...st.js => integration_automock_off.test.js} |  0
 .../{console-test.js => console.test.js}      |  0
 .../__tests__/{sum-test.js => sum.test.js}    |  0
 .../__tests__/{add-test.js => add.test.js}    |  0
 .../{add-fail-test.js => add_fail.test.js}    |  0
 .../custom_reporters/package.json             |  2 +-
 ...leteReporter.js => incomplete_reporter.js} |  0
 .../{TestReporter.js => test_reporter.js}     |  0
 ...mpty-suite-test.js => empty_suite.test.js} |  0
 .../__tests__/{env-test.js => env.test.js}    |  0
 ...-count-test.js => assertion_count.test.js} |  0
 ...r-test.js => node_assertion_error.test.js} |  0
 ...ow-number-test.js => throw_number.test.js} |  0
 ...ow-object-test.js => throw_object.test.js} |  0
 ...ow-string-test.js => throw_string.test.js} |  0
 ...{concurrent-test.js => concurrent.test.js} |  0
 ...rAll-test.js => promise_after_all.test.js} |  0
 ...ach-test.js => promise_after_each.test.js} |  0
 ...All-test.js => promise_before_all.test.js} |  0
 ...ch-test.js => promise_before_each.test.js} |  0
 ...romise_fit-test.js => promise_fit.test.js} |  0
 ...{promise_it-test.js => promise_it.test.js} |  0
 ...romise_xit-test.js => promise_xit.test.js} |  0
 ...alues-test.js => returning_values.test.js} |  0
 .../__tests__/{sum-test.js => sum.test.js}    |  0
 .../{dummy-test.js => dummy.test.js}          |  0
 ...mock-test.js => native_async_mock.test.js} |  0
 .../{node_path-test.js => node_path.test.js}  |  0
 ...th.test.js => regex_(char_in_path.test.js} |  0
 .../{resolve-test.js => resolve.test.js}      |  0
 ... runtime_internal_module_registry.test.js} |  0
 ...mmediate-test.js => set_immediate.test.js} |  0
 ...ner_patch-test.js => runner_patch.test.js} |  0
 .../{test1-test.js => test1.test.js}          |  0
 .../{test2-test.js => test2.test.js}          |  0
 .../{snapshot-test.js => snapshot.test.js}    |  0
 ...cape-regex.js => snapshot_escape_regex.js} |  0
 ...s => snapshot_escape_substitution.test.js} |  0
 .../{snapshot-test.js => snapshot.test.js}    |  0
 ...apshot-test.js => second_snapshot.test.js} |  0
 .../{snapshot-test.js => snapshot.test.js}    |  0
 ...me-error-test.js => runtime_error.test.js} |  0
 ...tack-trace-test.js => stack_trace.test.js} |  0
 ...js => stack_trace_without_message.test.js} |  0
 ...{test-error-test.js => test_error.test.js} |  0
 .../__tests__/{env-test.js => env.test.js}    |  0
 ...tern-test.js => test_name_pattern.test.js} |  0
 .../{processor-test.js => processor.test.js}  |  0
 .../with_resetMocks/timer_with_mock.test.js   |  1 +
 .../__tests__/use_real_timers.test.js         |  0
 .../package.json                              |  0
 ...{babel-jest-test.js => babel_jest.test.js} |  0
 ...or-test.js => custom_preprocessor.test.js} |  0
 ...nap => multiple_transformers.test.js.snap} |  0
 ...-test.js => multiple_transformers.test.js} |  0
 ...est.js => fails_with_syntax_error.test.js} |  0
 integration_tests/utils.js                    |  2 +-
 .../{verbose-test.js => verbose.test.js}      |  0
 package.json                                  |  4 +-
 packages/eslint-plugin-jest/src/index.js      |  8 +--
 ...tests-test.js => no_focused_tests.test.js} |  0
 ...tle-test.js => no_identical_title.test.js} |  0
 ...tests-test.js => no_skipped_tests.test.js} |  0
 ...id-expect-test.js => valid_expect.test.js} |  0
 ...disabled-tests.js => no_disabled_tests.js} |  0
 ...o-focused-tests.js => no_focused_tests.js} |  0
 ...entical-title.js => no_identical_title.js} |  0
 .../{valid-expect.js => valid_expect.js}      |  0
 .../__tests__/{git-test.js => git.test.js}    |  0
 .../src/__tests__/{hg-test.js => hg.test.js}  |  0
 .../src/{eventHandler.js => event_handler.js} |  0
 ...Errors.js => format_node_assert_errors.js} |  2 +-
 .../{jest-adapter.js => jest_adapter.js}      |  2 +-
 ...t-adapter-init.js => jest_adapter_init.js} |  0
 .../{jest-expect.js => jest_expect.js}        |  0
 packages/jest-circus/src/state.js             |  4 +-
 ...p => generate_empty_coverage.test.js.snap} |  0
 ...{watch-test.js.snap => watch.test.js.snap} |  0
 ... watch_filename_pattern_mode.test.js.snap} |  0
 ...watch_test_name_pattern_mode.test.js.snap} |  0
 ...est.js => generate_empty_coverage.test.js} |  0
 .../{globals-test.js => globals.test.js}      |  0
 ...chSource-test.js => search_source.test.js} |  0
 ...TestRunner-test.js => test_runner.test.js} | 27 ++++++--
 ...quencer-test.js => test_sequencer.test.js} |  0
 .../{watch-test.js => watch.test.js}          |  0
 ...js => watch_filename_pattern_mode.test.js} |  0
 ...s => watch_test_name_pattern_mode.test.js} |  0
 ... format_test_name_by_pattern.test.js.snap} |  0
 ...ht-test.js.snap => highlight.test.js.snap} | 66 +++++++++----------
 ...js => format_test_name_by_pattern.test.js} |  0
 ...orkers-test.js => get_max_workers.test.js} |  0
 .../{highlight-test.js => highlight.test.js}  | 16 ++---
 ...alidPath-test.js => is_valid_path.test.js} |  0
 ...ges-test.js => log_debug_messages.test.js} |  0
 .../{Prompt-test.js => prompt.test.js}        |  0
 ...scrollList-test.js => scroll_list.test.js} |  0
 ...ttern-test.js => validate_pattern.test.js} |  0
 ...{utils-test.js.snap => utils.test.js.snap} |  0
 ...rter-test.js => coverage_reporter.test.js} |  0
 ...Worker-test.js => coverage_worker.test.js} |  0
 .../{utils-test.js => utils.test.js}          |  0
 ...orter-test.js => verbose_reporter.test.js} |  0
 ...ze-test.js.snap => normalize.test.js.snap} |  0
 .../{normalize-test.js => normalize.test.js}  |  0
 ...FromArgv-test.js => set_from_argv.test.js} |  2 +-
 .../src/{findConfig.js => find_config.js}     |  0
 packages/jest-config/src/index.js             |  2 +-
 packages/jest-config/src/normalize.js         |  6 +-
 ...rrors.js => reporter_validation_errors.js} |  0
 .../src/{setFromArgv.js => set_from_argv.js}  |  0
 .../src/{validConfig.js => valid_config.js}   |  0
 .../{diff-test.js.snap => diff.test.js.snap}  |  0
 .../__tests__/{diff-test.js => diff.test.js}  |  0
 .../src/{diffStrings.js => diff_strings.js}   |  0
 packages/jest-diff/src/index.js               |  4 +-
 .../{index-test.js => index.test.js}          |  0
 ...nParser-test.js => babylon_parser.test.js} |  2 +-
 ...pace-test.js => project_workspace.test.js} |  2 +-
 .../{Runner-test.js => runner.test.js}        |  6 +-
 .../{Settings-test.js => settings.test.js}    |  4 +-
 ...nciler-test.js => test_reconciler.test.js} |  2 +-
 packages/jest-editor-support/src/index.js     | 14 ++--
 .../{BabylonParser.js => babylon_parser.js}   |  2 +-
 .../{ParserNodes.js => parser_nodes.js}       |  0
 .../src/{Process.js => process.js}            |  2 +-
 ...ojectWorkspace.js => project_workspace.js} |  0
 .../src/{Runner.js => runner.js}              |  4 +-
 .../src/{Settings.js => settings.js}          |  4 +-
 .../{TestReconciler.js => test_reconciler.js} |  0
 packages/jest-editor-support/src/types.js     |  2 +-
 ...nment-test.js => node_environment.test.js} |  0
 .../{index-test.js => index.test.js}          |  0
 ...{index-test.js.snap => index.test.js.snap} |  0
 ...MockName-test.js => get_mock_name.test.js} |  2 +-
 .../{index-test.js => index.test.js}          |  0
 .../{worker-test.js => worker.test.js}        |  0
 .../__tests__/{node-test.js => node.test.js}  |  0
 .../{watchman-test.js => watchman.test.js}    |  0
 .../src/{getMockName.js => get_mock_name.js}  |  0
 .../src/{HasteFS.js => haste_fs.js}           |  0
 packages/jest-haste-map/src/index.js          |  8 +--
 ...uires-test.js => extract_requires.test.js} |  2 +-
 ...test.js => get_platform_extension.test.js} |  2 +-
 ...extractRequires.js => extract_requires.js} |  0
 ...Extension.js => get_platform_extension.js} |  0
 .../src/{ModuleMap.js => module_map.js}       |  0
 packages/jest-haste-map/src/worker.js         |  2 +-
 ...> expectation_result_factory.test.js.snap} |  0
 ...ers-test.js.snap => matchers.test.js.snap} |  0
 ....js => expectation_result_factory.test.js} |  2 +-
 ...alias-test.js => it_to_test_alias.test.js} |  0
 .../{iterators-test.js => iterators.test.js}  |  0
 .../{matchers-test.js => matchers.test.js}    |  0
 .../{p-timeout-test.js => p_timeout.test.js}  |  2 +-
 ...eueRunner-test.js => queue_runner.test.js} |  2 +-
 .../{reporter-test.js => reporter.test.js}    |  0
 .../{assert-support.js => assert_support.js}  |  2 +-
 ...ctationFailed.js => expectation_failed.js} |  0
 ...ctory.js => expectation_result_factory.js} |  0
 packages/jest-jasmine2/src/index.js           |  8 +--
 .../{CallTracker.js => call_tracker.js}       |  0
 .../jasmine/{createSpy.js => create_spy.js}   |  4 +-
 .../src/jasmine/{Env.js => env.js}            |  4 +-
 .../{jasmine-light.js => jasmine_light.js}    | 16 ++---
 .../{JsApiReporter.js => js_api_reporter.js}  |  0
 ...portDispatcher.js => report_dispatcher.js} |  0
 .../src/jasmine/{Spec.js => spec.js}          |  6 +-
 .../{SpyRegistry.js => spy_registry.js}       |  6 +-
 .../{SpyStrategy.js => spy_strategy.js}       |  0
 .../src/jasmine/{Suite.js => suite.js}        |  4 +-
 .../src/jasmine/{Timer.js => timer.js}        |  0
 .../{jasmine-async.js => jasmine_async.js}    |  0
 .../src/{jest-expect.js => jest_expect.js}    |  0
 .../src/{p-timeout.js => p_timeout.js}        |  0
 .../src/{queueRunner.js => queue_runner.js}   |  2 +-
 ...-jest-globals.js => setup_jest_globals.js} |  0
 .../{treeProcessor.js => tree_processor.js}   |  0
 ...{index-test.js.snap => index.test.js.snap} |  0
 .../{index-test.js => index.test.js}          |  0
 ...xtend-test.js.snap => extend.test.js.snap} |  0
 ...ers-test.js.snap => matchers.test.js.snap} |  0
 ...test.js.snap => spy_matchers.test.js.snap} |  0
 ...js.snap => to_throw_matchers.test.js.snap} |  0
 ...ounts-test.js => assertion_counts.test.js} |  0
 ...rs-test.js => asymmetric_matchers.test.js} |  2 +-
 .../{extend-test.js => extend.test.js}        |  2 +-
 .../{matchers-test.js => matchers.test.js}    |  0
 ...yMatchers-test.js => spy_matchers.test.js} |  0
 ...ects-test.js => symbol_in_objects.test.js} |  0
 ...hers-test.js => to_throw_matchers.test.js} |  0
 .../{utils-test.js => utils.test.js}          |  0
 ...ric-matchers.js => asymmetric_matchers.js} |  2 +-
 ... => extract_expected_assertions_errors.js} |  2 +-
 packages/jest-matchers/src/index.js           | 13 ++--
 .../{jasmine-utils.js => jasmine_utils.js}    |  0
 ...hers-object.js => jest_matchers_object.js} |  0
 packages/jest-matchers/src/matchers.js        |  2 +-
 .../src/{spyMatchers.js => spy_matchers.js}   |  2 +-
 ...oThrowMatchers.js => to_throw_matchers.js} |  2 +-
 ...ges-test.js.snap => messages.test.js.snap} |  0
 .../{messages-test.js => messages.test.js}    |  0
 .../{jest-mock-test.js => jest_mock.test.js}  |  0
 .../{jest-repl-test.js => jest_repl.test.js}  |  0
 ...ated-test.js.snap => related.test.js.snap} |  0
 .../{file-test.js => file.test.js}            |  0
 .../{related-test.js => related.test.js}      |  0
 ...er-test.js => dependency_resolver.test.js} | 10 +--
 .../{resolve-test.js => resolve.test.js}      |  0
 ...defaultResolver.js => default_resolver.js} |  0
 packages/jest-resolve/src/index.js            |  2 +-
 .../src/__mocks__/createRuntime.js            |  2 +-
 ...s.snap => script_transformer.test.js.snap} |  0
 ...tation-test.js => instrumentation.test.js} |  2 +-
 ...rowser-test.js => resolve_browser.test.js} |  0
 ...untime-cli-test.js => runtime_cli.test.js} |  0
 ...nt-test.js => runtime_environment.test.js} |  0
 ...s => runtime_gen_mock_from_module.test.js} |  0
 ...est.js => runtime_internal_module.test.js} |  0
 ...On-test.js => runtime_jest_spy_on.test.js} |  0
 ...time-mock-test.js => runtime_mock.test.js} |  0
 ....js => runtime_module_directories.test.js} |  0
 ...PATH-test.js => runtime_node_path.test.js} |  0
 ...k-test.js => runtime_require_mock.test.js} |  0
 ...test.js => runtime_require_module.test.js} |  0
 ...=> runtime_require_module_or_mock.test.js} |  0
 ...re_module_or_mock_transitive_deps.test.js} |  0
 ...mer-test.js => script_transformer.test.js} |  2 +-
 packages/jest-runtime/src/index.js            |  4 +-
 ...ptTransformer.js => script_transformer.js} |  2 +-
 ...ouldInstrument.js => should_instrument.js} |  2 +-
 .../{matcher-test.js => matcher.test.js}      |  0
 .../{plugins-test.js => plugins.test.js}      |  0
 .../{utils-test.js => utils.test.js}          |  4 +-
 packages/jest-snapshot/src/index.js           |  2 +-
 .../jest-snapshot/src/{State.js => state.js}  |  0
 ...ser-test.js => type_script_parser.test.js} |  2 +-
 .../jest-test-typescript-parser/src/index.js  |  2 +-
 ...eScriptParser.js => type_script_parser.js} |  0
 packages/jest-util/src/Console.js             |  2 +-
 ...-test.js.snap => fake_timers.test.js.snap} |  0
 ...snap => validate_cli_options.test.js.snap} |  0
 ...FakeTimers-test.js => fake_timers.test.js} |  2 +-
 ...s-test.js => validate_cli_options.test.js} |  2 +-
 .../src/{clearLine.js => clear_line.js}       |  0
 .../src/{FakeTimers.js => fake_timers.js}     |  2 +-
 ...tTestResults.js => format_test_results.js} |  0
 packages/jest-util/src/index.js               | 14 ++--
 ...onGlobals.js => install_common_globals.js} |  0
 .../src/{NullConsole.js => null_console.js}   |  0
 .../src/{setGlobal.js => set_global.js}       |  0
 ...eCLIOptions.js => validate_cli_options.js} |  0
 ...ate-test.js.snap => validate.test.js.snap} |  0
 .../{jestConfig.js => jest_config.js}         |  0
 .../{validate-test.js => validate.test.js}    |  6 +-
 .../{defaultConfig.js => default_config.js}   |  2 +-
 .../{exampleConfig.js => example_config.js}   |  0
 packages/jest-validate/src/validate.js        |  2 +-
 packages/pretty-format/perf/test.js           |  2 +-
 ...{React-test.js.snap => react.test.js.snap} |  0
 ...her-test.js => asymmetric_matcher.test.js} |  2 +-
 ...nvertAnsi-test.js => convert_ansi.test.js} |  2 +-
 ...MLElement-test.js => html_element.test.js} |  2 +-
 .../{Immutable-test.js => immutable.test.js}  |  6 +-
 ...y-format-test.js => pretty_format.test.js} |  0
 .../{React-test.js => react.test.js}          |  4 +-
 packages/pretty-format/src/index.js           | 12 ++--
 ...metricMatcher.js => asymmetric_matcher.js} |  0
 .../{ConvertAnsi.js => convert_ansi.js}       |  0
 .../{HTMLElement.js => html_element.js}       |  2 +-
 .../{ImmutableList.js => immutable_list.js}   |  2 +-
 .../{ImmutableMap.js => immutable_map.js}     |  2 +-
 ...OrderedMap.js => immutable_ordered_map.js} |  2 +-
 ...OrderedSet.js => immutable_ordered_set.js} |  2 +-
 ...mutablePlugins.js => immutable_plugins.js} | 14 ++--
 ...ImmutableRecord.js => immutable_record.js} |  2 +-
 .../{ImmutableSet.js => immutable_set.js}     |  2 +-
 .../{ImmutableStack.js => immutable_stack.js} |  2 +-
 .../lib/{escapeHTML.js => escape_html.js}     |  0
 .../{printImmutable.js => print_immutable.js} |  0
 .../{ReactElement.js => react_element.js}     |  2 +-
 ...stComponent.js => react_test_component.js} |  2 +-
 362 files changed, 378 insertions(+), 356 deletions(-)
 rename examples/async/__tests__/{user-test.js => user.test.js} (100%)
 rename examples/enzyme/__tests__/{CheckboxWithLabel-test.js => checkbox_with_label.test.js} (100%)
 rename examples/jquery/__tests__/{displayUser-test.js => display_user.test.js} (100%)
 rename examples/jquery/__tests__/{fetchCurrentUser-test.js => fetch_current_user.test.js} (100%)
 rename examples/manual_mocks/__tests__/{FileSummarizer-test.js => file_summarizer.test.js} (100%)
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 rename packages/jest-jasmine2/src/jasmine/{Timer.js => timer.js} (100%)
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 rename packages/jest-matchers/src/__tests__/__snapshots__/{spyMatchers-test.js.snap => spy_matchers.test.js.snap} (100%)
 rename packages/jest-matchers/src/__tests__/__snapshots__/{toThrowMatchers-test.js.snap => to_throw_matchers.test.js.snap} (100%)
 rename packages/jest-matchers/src/__tests__/{assertion-counts-test.js => assertion_counts.test.js} (100%)
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 rename packages/jest-message-util/src/__tests__/{messages-test.js => messages.test.js} (100%)
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 rename packages/jest-resolve-dependencies/src/__tests__/__fixtures__/__snapshots__/{related-test.js.snap => related.test.js.snap} (100%)
 rename packages/jest-resolve-dependencies/src/__tests__/__fixtures__/{file-test.js => file.test.js} (100%)
 rename packages/jest-resolve-dependencies/src/__tests__/__fixtures__/{related-test.js => related.test.js} (100%)
 rename packages/jest-resolve-dependencies/src/__tests__/{DependencyResolver-test.js => dependency_resolver.test.js} (89%)
 rename packages/jest-resolve/src/__tests__/{resolve-test.js => resolve.test.js} (100%)
 rename packages/jest-resolve/src/{defaultResolver.js => default_resolver.js} (100%)
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 rename packages/jest-runtime/src/__tests__/{instrumentation-test.js => instrumentation.test.js} (94%)
 rename packages/jest-runtime/src/__tests__/{Resolve-browser-test.js => resolve_browser.test.js} (100%)
 rename packages/jest-runtime/src/__tests__/{Runtime-cli-test.js => runtime_cli.test.js} (100%)
 rename packages/jest-runtime/src/__tests__/{Runtime-environment-test.js => runtime_environment.test.js} (100%)
 rename packages/jest-runtime/src/__tests__/{Runtime-genMockFromModule-test.js => runtime_gen_mock_from_module.test.js} (100%)
 rename packages/jest-runtime/src/__tests__/{Runtime-internalModule-test.js => runtime_internal_module.test.js} (100%)
 rename packages/jest-runtime/src/__tests__/{Runtime-jest-spyOn-test.js => runtime_jest_spy_on.test.js} (100%)
 rename packages/jest-runtime/src/__tests__/{Runtime-mock-test.js => runtime_mock.test.js} (100%)
 rename packages/jest-runtime/src/__tests__/{Runtime-moduleDirectories-test.js => runtime_module_directories.test.js} (100%)
 rename packages/jest-runtime/src/__tests__/{Runtime-NODE_PATH-test.js => runtime_node_path.test.js} (100%)
 rename packages/jest-runtime/src/__tests__/{Runtime-requireMock-test.js => runtime_require_mock.test.js} (100%)
 rename packages/jest-runtime/src/__tests__/{Runtime-requireModule-test.js => runtime_require_module.test.js} (100%)
 rename packages/jest-runtime/src/__tests__/{Runtime-requireModuleOrMock-test.js => runtime_require_module_or_mock.test.js} (100%)
 rename packages/jest-runtime/src/__tests__/{Runtime-requireModuleOrMock-transitive-deps-test.js => runtime_require_module_or_mock_transitive_deps.test.js} (100%)
 rename packages/jest-runtime/src/__tests__/{ScriptTransformer-test.js => script_transformer.test.js} (99%)
 rename packages/jest-runtime/src/{ScriptTransformer.js => script_transformer.js} (99%)
 rename packages/jest-runtime/src/{shouldInstrument.js => should_instrument.js} (97%)
 rename packages/jest-snapshot/src/__tests__/{matcher-test.js => matcher.test.js} (100%)
 rename packages/jest-snapshot/src/__tests__/{plugins-test.js => plugins.test.js} (100%)
 rename packages/jest-snapshot/src/__tests__/{utils-test.js => utils.test.js} (98%)
 rename packages/jest-snapshot/src/{State.js => state.js} (100%)
 rename packages/jest-test-typescript-parser/src/__tests__/{TypeScriptParser-test.js => type_script_parser.test.js} (89%)
 rename packages/jest-test-typescript-parser/src/{TypeScriptParser.js => type_script_parser.js} (100%)
 rename packages/jest-util/src/__tests__/__snapshots__/{FakeTimers-test.js.snap => fake_timers.test.js.snap} (100%)
 rename packages/jest-util/src/__tests__/__snapshots__/{validateCLIOptions-test.js.snap => validate_cli_options.test.js.snap} (100%)
 rename packages/jest-util/src/__tests__/{FakeTimers-test.js => fake_timers.test.js} (99%)
 rename packages/jest-util/src/__tests__/{validateCLIOptions-test.js => validate_cli_options.test.js} (94%)
 rename packages/jest-util/src/{clearLine.js => clear_line.js} (100%)
 rename packages/jest-util/src/{FakeTimers.js => fake_timers.js} (99%)
 rename packages/jest-util/src/{formatTestResults.js => format_test_results.js} (100%)
 rename packages/jest-util/src/{installCommonGlobals.js => install_common_globals.js} (100%)
 rename packages/jest-util/src/{NullConsole.js => null_console.js} (100%)
 rename packages/jest-util/src/{setGlobal.js => set_global.js} (100%)
 rename packages/jest-util/src/{validateCLIOptions.js => validate_cli_options.js} (100%)
 rename packages/jest-validate/src/__tests__/__snapshots__/{validate-test.js.snap => validate.test.js.snap} (100%)
 rename packages/jest-validate/src/__tests__/fixtures/{jestConfig.js => jest_config.js} (100%)
 rename packages/jest-validate/src/__tests__/{validate-test.js => validate.test.js} (95%)
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 rename packages/pretty-format/src/__tests__/{ConvertAnsi-test.js => convert_ansi.test.js} (96%)
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diff --git a/examples/async/__tests__/user-test.js b/examples/async/__tests__/user.test.js
similarity index 100%
rename from examples/async/__tests__/user-test.js
rename to examples/async/__tests__/user.test.js
diff --git a/examples/enzyme/__tests__/CheckboxWithLabel-test.js b/examples/enzyme/__tests__/checkbox_with_label.test.js
similarity index 100%
rename from examples/enzyme/__tests__/CheckboxWithLabel-test.js
rename to examples/enzyme/__tests__/checkbox_with_label.test.js
diff --git a/examples/jquery/__tests__/displayUser-test.js b/examples/jquery/__tests__/display_user.test.js
similarity index 100%
rename from examples/jquery/__tests__/displayUser-test.js
rename to examples/jquery/__tests__/display_user.test.js
diff --git a/examples/jquery/__tests__/fetchCurrentUser-test.js b/examples/jquery/__tests__/fetch_current_user.test.js
similarity index 100%
rename from examples/jquery/__tests__/fetchCurrentUser-test.js
rename to examples/jquery/__tests__/fetch_current_user.test.js
diff --git a/examples/manual_mocks/__tests__/FileSummarizer-test.js b/examples/manual_mocks/__tests__/file_summarizer.test.js
similarity index 100%
rename from examples/manual_mocks/__tests__/FileSummarizer-test.js
rename to examples/manual_mocks/__tests__/file_summarizer.test.js
diff --git a/examples/react-native/__tests__/__snapshots__/Intro-test.js.snap b/examples/react-native/__tests__/__snapshots__/intro.test.js.snap
similarity index 100%
rename from examples/react-native/__tests__/__snapshots__/Intro-test.js.snap
rename to examples/react-native/__tests__/__snapshots__/intro.test.js.snap
diff --git a/examples/react-native/__tests__/Intro-test.js b/examples/react-native/__tests__/intro.test.js
similarity index 100%
rename from examples/react-native/__tests__/Intro-test.js
rename to examples/react-native/__tests__/intro.test.js
diff --git a/examples/react/__tests__/CheckboxWithLabel-test.js b/examples/react/__tests__/checkbox_with_label.test.js
similarity index 100%
rename from examples/react/__tests__/CheckboxWithLabel-test.js
rename to examples/react/__tests__/checkbox_with_label.test.js
diff --git a/examples/snapshot/__tests__/__snapshots__/Clock.react-test.js.snap b/examples/snapshot/__tests__/__snapshots__/clock.react.test.js.snap
similarity index 100%
rename from examples/snapshot/__tests__/__snapshots__/Clock.react-test.js.snap
rename to examples/snapshot/__tests__/__snapshots__/clock.react.test.js.snap
diff --git a/examples/snapshot/__tests__/__snapshots__/Link.react-test.js.snap b/examples/snapshot/__tests__/__snapshots__/link.react.test.js.snap
similarity index 100%
rename from examples/snapshot/__tests__/__snapshots__/Link.react-test.js.snap
rename to examples/snapshot/__tests__/__snapshots__/link.react.test.js.snap
diff --git a/examples/snapshot/__tests__/Clock.react-test.js b/examples/snapshot/__tests__/clock.react.test.js
similarity index 100%
rename from examples/snapshot/__tests__/Clock.react-test.js
rename to examples/snapshot/__tests__/clock.react.test.js
diff --git a/examples/snapshot/__tests__/Link.react-test.js b/examples/snapshot/__tests__/link.react.test.js
similarity index 100%
rename from examples/snapshot/__tests__/Link.react-test.js
rename to examples/snapshot/__tests__/link.react.test.js
diff --git a/examples/timer/__tests__/infiniteTimerGame-test.js b/examples/timer/__tests__/infinite_timer_game.test.js
similarity index 100%
rename from examples/timer/__tests__/infiniteTimerGame-test.js
rename to examples/timer/__tests__/infinite_timer_game.test.js
diff --git a/examples/timer/__tests__/timerGame-test.js b/examples/timer/__tests__/timer_game.test.js
similarity index 100%
rename from examples/timer/__tests__/timerGame-test.js
rename to examples/timer/__tests__/timer_game.test.js
diff --git a/examples/typescript/__tests__/CheckboxWithLabel-test.tsx b/examples/typescript/__tests__/checkbox_with_label.test.tsx
similarity index 100%
rename from examples/typescript/__tests__/CheckboxWithLabel-test.tsx
rename to examples/typescript/__tests__/checkbox_with_label.test.tsx
diff --git a/examples/typescript/__tests__/sum-test.js b/examples/typescript/__tests__/sum.test.js
similarity index 100%
rename from examples/typescript/__tests__/sum-test.js
rename to examples/typescript/__tests__/sum.test.js
diff --git a/integration_tests/__tests__/__snapshots__/console-test.js.snap b/integration_tests/__tests__/__snapshots__/console.test.js.snap
similarity index 71%
rename from integration_tests/__tests__/__snapshots__/console-test.js.snap
rename to integration_tests/__tests__/__snapshots__/console.test.js.snap
index a327e3efea5b..7215dd4217bb 100644
--- a/integration_tests/__tests__/__snapshots__/console-test.js.snap
+++ b/integration_tests/__tests__/__snapshots__/console.test.js.snap
@@ -1,16 +1,16 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
 exports[`console printing 1`] = `
-" PASS  __tests__/console-test.js
+" PASS  __tests__/console.test.js
   ● Console
 
-    console.log __tests__/console-test.js:11
+    console.log __tests__/console.test.js:11
       This is a log message.
-    console.info __tests__/console-test.js:13
+    console.info __tests__/console.test.js:13
       This is an info message.
-    console.warn __tests__/console-test.js:15
+    console.warn __tests__/console.test.js:15
       This is a warning message.
-    console.error __tests__/console-test.js:17
+    console.error __tests__/console.test.js:17
       This is an error message.
 
 
@@ -27,23 +27,23 @@ Ran all test suites.
 `;
 
 exports[`console printing with --verbose 1`] = `
-"  console.log __tests__/console-test.js:11
+"  console.log __tests__/console.test.js:11
     This is a log message.
 
-  console.info __tests__/console-test.js:13
+  console.info __tests__/console.test.js:13
     This is an info message.
 
-  console.warn __tests__/console-test.js:15
+  console.warn __tests__/console.test.js:15
     This is a warning message.
 
-  console.error __tests__/console-test.js:17
+  console.error __tests__/console.test.js:17
     This is an error message.
 
 "
 `;
 
 exports[`console printing with --verbose 2`] = `
-" PASS  __tests__/console-test.js
+" PASS  __tests__/console.test.js
   ✓ works just fine
 
 "
@@ -61,7 +61,7 @@ Ran all test suites.
 exports[`does not print to console with --silent 1`] = `""`;
 
 exports[`does not print to console with --silent 2`] = `
-" PASS  __tests__/console-test.js
+" PASS  __tests__/console.test.js
 
 "
 `;
diff --git a/integration_tests/__tests__/__snapshots__/coverage-remapping-test.js.snap b/integration_tests/__tests__/__snapshots__/coverage_remapping.test.js.snap
similarity index 100%
rename from integration_tests/__tests__/__snapshots__/coverage-remapping-test.js.snap
rename to integration_tests/__tests__/__snapshots__/coverage_remapping.test.js.snap
diff --git a/integration_tests/__tests__/__snapshots__/coverage_report-test.js.snap b/integration_tests/__tests__/__snapshots__/coverage_report.test.js.snap
similarity index 100%
rename from integration_tests/__tests__/__snapshots__/coverage_report-test.js.snap
rename to integration_tests/__tests__/__snapshots__/coverage_report.test.js.snap
diff --git a/integration_tests/__tests__/__snapshots__/coverage-threshold-test.js.snap b/integration_tests/__tests__/__snapshots__/coverage_threshold.test.js.snap
similarity index 100%
rename from integration_tests/__tests__/__snapshots__/coverage-threshold-test.js.snap
rename to integration_tests/__tests__/__snapshots__/coverage_threshold.test.js.snap
diff --git a/integration_tests/__tests__/__snapshots__/custom-reporters-test.js.snap b/integration_tests/__tests__/__snapshots__/custom_reporters.test.js.snap
similarity index 84%
rename from integration_tests/__tests__/__snapshots__/custom-reporters-test.js.snap
rename to integration_tests/__tests__/__snapshots__/custom_reporters.test.js.snap
index f6b9d7c37f93..eba40a73f12c 100644
--- a/integration_tests/__tests__/__snapshots__/custom-reporters-test.js.snap
+++ b/integration_tests/__tests__/__snapshots__/custom_reporters.test.js.snap
@@ -34,14 +34,14 @@ Object {
     "hello": "world",
     "maxWorkers": "<<REPLACED>>",
     "pattern": Object {
-      "input": "add-fail-test.js",
+      "input": "add_fail.test.js",
       "paths": Array [
-        "add-fail-test.js",
+        "add_fail.test.js",
       ],
       "shouldTreatInputAsPattern": false,
-      "testPathPattern": "add-fail-test.js",
+      "testPathPattern": "add_fail.test.js",
     },
-    "testPathPattern": "\\"add-fail-test.js\\"",
+    "testPathPattern": "\\"add_fail.test.js\\"",
   },
 }
 `;
@@ -72,20 +72,20 @@ Object {
     "hello": "world",
     "maxWorkers": "<<REPLACED>>",
     "pattern": Object {
-      "input": "add-test.js",
+      "input": "add.test.js",
       "paths": Array [
-        "add-test.js",
+        "add.test.js",
       ],
       "shouldTreatInputAsPattern": false,
-      "testPathPattern": "add-test.js",
+      "testPathPattern": "add.test.js",
     },
-    "testPathPattern": "\\"add-test.js\\"",
+    "testPathPattern": "\\"add.test.js\\"",
   },
 }
 `;
 
 exports[`Custom Reporters Integration default reporters enabled 1`] = `
-" PASS  __tests__/add-test.js
+" PASS  __tests__/add.test.js
   Custom Reporters
     ✓ adds ok
 
@@ -97,7 +97,7 @@ exports[`Custom Reporters Integration default reporters enabled 2`] = `
 Tests:       1 passed, 1 total
 Snapshots:   0 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"add-test.js\\".
+Ran all test suites matching \\"add.test.js\\".
 "
 `;
 
@@ -124,14 +124,14 @@ Object {
   "options": Object {
     "maxWorkers": "<<REPLACED>>",
     "pattern": Object {
-      "input": "add-test.js",
+      "input": "add.test.js",
       "paths": Array [
-        "add-test.js",
+        "add.test.js",
       ],
       "shouldTreatInputAsPattern": false,
-      "testPathPattern": "add-test.js",
+      "testPathPattern": "add.test.js",
     },
-    "testPathPattern": "\\"add-test.js\\"",
+    "testPathPattern": "\\"add.test.js\\"",
   },
 }
 `;
diff --git a/integration_tests/__tests__/__snapshots__/failures-test.js.snap b/integration_tests/__tests__/__snapshots__/failures.test.js.snap
similarity index 83%
rename from integration_tests/__tests__/__snapshots__/failures-test.js.snap
rename to integration_tests/__tests__/__snapshots__/failures.test.js.snap
index c45d6dc788da..f3f64ce993f4 100644
--- a/integration_tests/__tests__/__snapshots__/failures-test.js.snap
+++ b/integration_tests/__tests__/__snapshots__/failures.test.js.snap
@@ -1,7 +1,7 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
 exports[`not throwing Error objects 1`] = `
-" FAIL  __tests__/throw-number-test.js
+" FAIL  __tests__/throw_number.test.js
   ● Test suite failed to run
 
     Expected an Error, but \\"1\\" was thrown
@@ -10,7 +10,7 @@ exports[`not throwing Error objects 1`] = `
 `;
 
 exports[`not throwing Error objects 2`] = `
-" FAIL  __tests__/throw-string-test.js
+" FAIL  __tests__/throw_string.test.js
   ● Test suite failed to run
 
     Error
@@ -20,7 +20,7 @@ exports[`not throwing Error objects 2`] = `
 `;
 
 exports[`not throwing Error objects 3`] = `
-" FAIL  __tests__/throw-object-test.js
+" FAIL  __tests__/throw_object.test.js
   ● Test suite failed to run
 
     Error: No message was provided
@@ -29,12 +29,12 @@ exports[`not throwing Error objects 3`] = `
 `;
 
 exports[`not throwing Error objects 4`] = `
-" FAIL  __tests__/assertion-count-test.js
+" FAIL  __tests__/assertion_count.test.js
   ● .assertions() › throws
     expect(received).toBeTruthy()
     Expected value to be truthy, instead received
       false
-      at __tests__/assertion-count-test.js:14:17
+      at __tests__/assertion_count.test.js:14:17
   ● .assertions() › throws
     expect.assertions(2)
     Expected two assertions to be called but only received one assertion call.
@@ -42,7 +42,7 @@ exports[`not throwing Error objects 4`] = `
     expect(received).toBeTruthy()
     Expected value to be truthy, instead received
       false
-      at __tests__/assertion-count-test.js:18:17
+      at __tests__/assertion_count.test.js:18:17
   ● .assertions() › throws on assertion
     expect.assertions(0)
     Expected zero assertions to be called but only received one assertion call.
@@ -59,7 +59,7 @@ exports[`not throwing Error objects 4`] = `
 `;
 
 exports[`works with node assert 1`] = `
-" FAIL  __tests__/node-assertion-error-test.js
+" FAIL  __tests__/node_assertion_error.test.js
   ● assert
 
     assert.equal(received, expected) or assert(received) 
@@ -69,7 +69,7 @@ exports[`works with node assert 1`] = `
     Received:
       false
       
-      at __tests__/node-assertion-error-test.js:16:3
+      at __tests__/node_assertion_error.test.js:16:3
 
   ● assert with a message
 
@@ -83,7 +83,7 @@ exports[`works with node assert 1`] = `
     Message:
       this is a message
       
-      at __tests__/node-assertion-error-test.js:20:3
+      at __tests__/node_assertion_error.test.js:20:3
 
   ● assert.ok
 
@@ -94,7 +94,7 @@ exports[`works with node assert 1`] = `
     Received:
       false
       
-      at __tests__/node-assertion-error-test.js:24:10
+      at __tests__/node_assertion_error.test.js:24:10
 
   ● assert.ok with a message
 
@@ -108,7 +108,7 @@ exports[`works with node assert 1`] = `
     Message:
       this is a message
       
-      at __tests__/node-assertion-error-test.js:28:10
+      at __tests__/node_assertion_error.test.js:28:10
 
   ● assert.equal
 
@@ -119,7 +119,7 @@ exports[`works with node assert 1`] = `
     Received:
       1
       
-      at __tests__/node-assertion-error-test.js:32:10
+      at __tests__/node_assertion_error.test.js:32:10
 
   ● assert.notEqual
 
@@ -134,7 +134,7 @@ exports[`works with node assert 1`] = `
     
     Compared values have no visual difference.
       
-      at __tests__/node-assertion-error-test.js:36:10
+      at __tests__/node_assertion_error.test.js:36:10
 
   ● assert.deepEqual
 
@@ -159,7 +159,7 @@ exports[`works with node assert 1`] = `
         },
       }
       
-      at __tests__/node-assertion-error-test.js:40:10
+      at __tests__/node_assertion_error.test.js:40:10
 
   ● assert.deepEqual with a message
 
@@ -187,7 +187,7 @@ exports[`works with node assert 1`] = `
         },
       }
       
-      at __tests__/node-assertion-error-test.js:44:10
+      at __tests__/node_assertion_error.test.js:44:10
 
   ● assert.notDeepEqual
 
@@ -202,7 +202,7 @@ exports[`works with node assert 1`] = `
     
     Compared values have no visual difference.
       
-      at __tests__/node-assertion-error-test.js:48:10
+      at __tests__/node_assertion_error.test.js:48:10
 
   ● assert.strictEqual
 
@@ -213,7 +213,7 @@ exports[`works with node assert 1`] = `
     Received:
       1
       
-      at __tests__/node-assertion-error-test.js:52:10
+      at __tests__/node_assertion_error.test.js:52:10
 
   ● assert.notStrictEqual
 
@@ -231,7 +231,7 @@ exports[`works with node assert 1`] = `
     
     Compared values have no visual difference.
       
-      at __tests__/node-assertion-error-test.js:56:10
+      at __tests__/node_assertion_error.test.js:56:10
 
   ● assert.deepStrictEqual
 
@@ -252,7 +252,7 @@ exports[`works with node assert 1`] = `
     +   \\"a\\": 1,
       }
       
-      at __tests__/node-assertion-error-test.js:60:10
+      at __tests__/node_assertion_error.test.js:60:10
 
   ● assert.notDeepStrictEqual
 
@@ -267,7 +267,7 @@ exports[`works with node assert 1`] = `
     
     Compared values have no visual difference.
       
-      at __tests__/node-assertion-error-test.js:64:10
+      at __tests__/node_assertion_error.test.js:64:10
 
   ● assert.ifError
 
@@ -285,7 +285,7 @@ exports[`works with node assert 1`] = `
     Message:
       Got unwanted exception.
       
-      at __tests__/node-assertion-error-test.js:72:10
+      at __tests__/node_assertion_error.test.js:72:10
 
   ● assert.throws
 
@@ -297,7 +297,7 @@ exports[`works with node assert 1`] = `
     Message:
       Missing expected exception.
       
-      at __tests__/node-assertion-error-test.js:78:10
+      at __tests__/node_assertion_error.test.js:78:10
 
   ✕ assert
   ✕ assert with a message
diff --git a/integration_tests/__tests__/__snapshots__/globals-test.js.snap b/integration_tests/__tests__/__snapshots__/globals.test.js.snap
similarity index 88%
rename from integration_tests/__tests__/__snapshots__/globals-test.js.snap
rename to integration_tests/__tests__/__snapshots__/globals.test.js.snap
index c6fd3195c305..b40dfdc8f509 100644
--- a/integration_tests/__tests__/__snapshots__/globals-test.js.snap
+++ b/integration_tests/__tests__/__snapshots__/globals.test.js.snap
@@ -1,7 +1,7 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
 exports[`basic test constructs 1`] = `
-" PASS  __tests__/basic-test-constructs-test.js
+" PASS  __tests__/basic.test-constructs.test.js
   ✓ it
   ✓ test
   describe
@@ -21,7 +21,7 @@ Ran all test suites.
 `;
 
 exports[`only 1`] = `
-" PASS  __tests__/only-constructs-test.js
+" PASS  __tests__/only-constructs.test.js
   ✓ test.only
   ✓ it.only
   ✓ fit
@@ -47,7 +47,7 @@ Ran all test suites.
 `;
 
 exports[`only with expand arg 1`] = `
-" PASS  __tests__/only-constructs-test.js
+" PASS  __tests__/only-constructs.test.js
   ○ it
   ✓ test.only
   ✓ it.only
@@ -73,7 +73,7 @@ Ran all test suites.
 `;
 
 exports[`skips 1`] = `
-" PASS  __tests__/skips-constructs-test.js
+" PASS  __tests__/skips-constructs.test.js
   ✓ it
   ○ skipped 4 tests
   xdescribe
@@ -96,7 +96,7 @@ Ran all test suites.
 `;
 
 exports[`skips with expand arg 1`] = `
-" PASS  __tests__/skips-constructs-test.js
+" PASS  __tests__/skips-constructs.test.js
   ✓ it
   ○ xtest
   ○ xit
@@ -123,7 +123,7 @@ Ran all test suites.
 `;
 
 exports[`tests with no implementation 1`] = `
-" PASS  __tests__/only-constructs-test.js
+" PASS  __tests__/only-constructs.test.js
   ✓ it
   ○ skipped 2 tests
 
@@ -140,7 +140,7 @@ Ran all test suites.
 `;
 
 exports[`tests with no implementation with expand arg 1`] = `
-" PASS  __tests__/only-constructs-test.js
+" PASS  __tests__/only-constructs.test.js
   ✓ it
   ○ it, no implementation
   ○ test, no implementation
diff --git a/integration_tests/__tests__/__snapshots__/jest.config.js-test.js.snap b/integration_tests/__tests__/__snapshots__/jest.config.js.test.js.snap
similarity index 100%
rename from integration_tests/__tests__/__snapshots__/jest.config.js-test.js.snap
rename to integration_tests/__tests__/__snapshots__/jest.config.js.test.js.snap
diff --git a/integration_tests/__tests__/__snapshots__/showConfig-test.js.snap b/integration_tests/__tests__/__snapshots__/show_config.test.js.snap
similarity index 100%
rename from integration_tests/__tests__/__snapshots__/showConfig-test.js.snap
rename to integration_tests/__tests__/__snapshots__/show_config.test.js.snap
diff --git a/integration_tests/__tests__/__snapshots__/snapshot-test.js.snap b/integration_tests/__tests__/__snapshots__/snapshot.test.js.snap
similarity index 90%
rename from integration_tests/__tests__/__snapshots__/snapshot-test.js.snap
rename to integration_tests/__tests__/__snapshots__/snapshot.test.js.snap
index 90db2bdc908c..19d85d8f6d8c 100644
--- a/integration_tests/__tests__/__snapshots__/snapshot-test.js.snap
+++ b/integration_tests/__tests__/__snapshots__/snapshot.test.js.snap
@@ -95,7 +95,7 @@ exports[`Snapshot works with escaped characters 1`] = `
 Tests:       1 passed, 1 total
 Snapshots:   1 added, 1 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"snapshot-test.js\\".
+Ran all test suites matching \\"snapshot.test.js\\".
 "
 `;
 
@@ -104,7 +104,7 @@ exports[`Snapshot works with escaped characters 2`] = `
 Tests:       2 passed, 2 total
 Snapshots:   1 added, 1 passed, 2 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"snapshot-test.js\\".
+Ran all test suites matching \\"snapshot.test.js\\".
 "
 `;
 
@@ -113,7 +113,7 @@ exports[`Snapshot works with escaped characters 3`] = `
 Tests:       2 passed, 2 total
 Snapshots:   2 passed, 2 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"snapshot-test.js\\".
+Ran all test suites matching \\"snapshot.test.js\\".
 "
 `;
 
@@ -122,7 +122,7 @@ exports[`Snapshot works with escaped regex 1`] = `
 Tests:       2 passed, 2 total
 Snapshots:   2 added, 2 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"snapshot-escape-regex.js\\".
+Ran all test suites matching \\"snapshot_escape_regex.js\\".
 "
 `;
 
@@ -131,7 +131,7 @@ exports[`Snapshot works with escaped regex 2`] = `
 Tests:       2 passed, 2 total
 Snapshots:   2 passed, 2 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"snapshot-escape-regex.js\\".
+Ran all test suites matching \\"snapshot_escape_regex.js\\".
 "
 `;
 
@@ -140,7 +140,7 @@ exports[`Snapshot works with template literal subsitutions 1`] = `
 Tests:       1 passed, 1 total
 Snapshots:   1 added, 1 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"snapshot-escape-substitution-test.js\\".
+Ran all test suites matching \\"snapshot_escape_substitution.test.js\\".
 "
 `;
 
@@ -149,6 +149,6 @@ exports[`Snapshot works with template literal subsitutions 2`] = `
 Tests:       1 passed, 1 total
 Snapshots:   1 passed, 1 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"snapshot-escape-substitution-test.js\\".
+Ran all test suites matching \\"snapshot_escape_substitution.test.js\\".
 "
 `;
diff --git a/integration_tests/__tests__/__snapshots__/snapshot-serializers-test.js.snap b/integration_tests/__tests__/__snapshots__/snapshot_serializers.test.js.snap
similarity index 100%
rename from integration_tests/__tests__/__snapshots__/snapshot-serializers-test.js.snap
rename to integration_tests/__tests__/__snapshots__/snapshot_serializers.test.js.snap
diff --git a/integration_tests/__tests__/__snapshots__/stack_trace-test.js.snap b/integration_tests/__tests__/__snapshots__/stack_trace.test.js.snap
similarity index 78%
rename from integration_tests/__tests__/__snapshots__/stack_trace-test.js.snap
rename to integration_tests/__tests__/__snapshots__/stack_trace.test.js.snap
index da982fbd5eb9..3477c6847149 100644
--- a/integration_tests/__tests__/__snapshots__/stack_trace-test.js.snap
+++ b/integration_tests/__tests__/__snapshots__/stack_trace.test.js.snap
@@ -5,7 +5,7 @@ exports[`Stack Trace does not print a stack trace for errors when --noStackTrace
 Tests:       3 failed, 3 total
 Snapshots:   0 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"test-error-test.js\\".
+Ran all test suites matching \\"test_error.test.js\\".
 "
 `;
 
@@ -14,7 +14,7 @@ exports[`Stack Trace does not print a stack trace for matching errors when --noS
 Tests:       1 failed, 1 total
 Snapshots:   0 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"stack-trace-test.js\\".
+Ran all test suites matching \\"stack_trace.test.js\\".
 "
 `;
 
@@ -23,7 +23,7 @@ exports[`Stack Trace does not print a stack trace for runtime errors when --noSt
 Tests:       0 total
 Snapshots:   0 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"runtime-error-test.js\\".
+Ran all test suites matching \\"runtime_error.test.js\\".
 "
 `;
 
@@ -32,7 +32,7 @@ exports[`Stack Trace prints a stack trace for errors 1`] = `
 Tests:       3 failed, 3 total
 Snapshots:   0 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"test-error-test.js\\".
+Ran all test suites matching \\"test_error.test.js\\".
 "
 `;
 
@@ -41,7 +41,7 @@ exports[`Stack Trace prints a stack trace for errors without message in stack tr
 Tests:       1 failed, 1 total
 Snapshots:   0 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"stack-trace-without-message-test.js\\".
+Ran all test suites matching \\"stack_trace_without_message.test.js\\".
 "
 `;
 
@@ -50,7 +50,7 @@ exports[`Stack Trace prints a stack trace for matching errors 1`] = `
 Tests:       1 failed, 1 total
 Snapshots:   0 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"stack-trace-test.js\\".
+Ran all test suites matching \\"stack_trace.test.js\\".
 "
 `;
 
@@ -59,6 +59,6 @@ exports[`Stack Trace prints a stack trace for runtime errors 1`] = `
 Tests:       0 total
 Snapshots:   0 total
 Time:        <<REPLACED>>
-Ran all test suites matching \\"runtime-error-test.js\\".
+Ran all test suites matching \\"runtime_error.test.js\\".
 "
 `;
diff --git a/integration_tests/__tests__/__snapshots__/testNamePattern-test.js.snap b/integration_tests/__tests__/__snapshots__/test_name_pattern.test.js.snap
similarity index 100%
rename from integration_tests/__tests__/__snapshots__/testNamePattern-test.js.snap
rename to integration_tests/__tests__/__snapshots__/test_name_pattern.test.js.snap
diff --git a/integration_tests/__tests__/__snapshots__/timeouts-test.js.snap b/integration_tests/__tests__/__snapshots__/timeouts.test.js.snap
similarity index 100%
rename from integration_tests/__tests__/__snapshots__/timeouts-test.js.snap
rename to integration_tests/__tests__/__snapshots__/timeouts.test.js.snap
diff --git a/integration_tests/__tests__/__snapshots__/transform-test.js.snap b/integration_tests/__tests__/__snapshots__/transform.test.js.snap
similarity index 100%
rename from integration_tests/__tests__/__snapshots__/transform-test.js.snap
rename to integration_tests/__tests__/__snapshots__/transform.test.js.snap
diff --git a/integration_tests/__tests__/__snapshots__/typescript-coverage-test.js.snap b/integration_tests/__tests__/__snapshots__/typescript_coverage.test.js.snap
similarity index 100%
rename from integration_tests/__tests__/__snapshots__/typescript-coverage-test.js.snap
rename to integration_tests/__tests__/__snapshots__/typescript_coverage.test.js.snap
diff --git a/integration_tests/__tests__/auto-clear-mocks-test.js b/integration_tests/__tests__/auto_clear_mocks.test.js
similarity index 100%
rename from integration_tests/__tests__/auto-clear-mocks-test.js
rename to integration_tests/__tests__/auto_clear_mocks.test.js
diff --git a/integration_tests/__tests__/auto-reset-mocks-test.js b/integration_tests/__tests__/auto_reset_mocks.test.js
similarity index 100%
rename from integration_tests/__tests__/auto-reset-mocks-test.js
rename to integration_tests/__tests__/auto_reset_mocks.test.js
diff --git a/integration_tests/__tests__/babel-plugin-jest-hoist-test.js b/integration_tests/__tests__/babel_plugin_jest_hoist.test.js
similarity index 100%
rename from integration_tests/__tests__/babel-plugin-jest-hoist-test.js
rename to integration_tests/__tests__/babel_plugin_jest_hoist.test.js
diff --git a/integration_tests/__tests__/compare-dom-nodes-test.js b/integration_tests/__tests__/compare_dom_nodes.test.js
similarity index 100%
rename from integration_tests/__tests__/compare-dom-nodes-test.js
rename to integration_tests/__tests__/compare_dom_nodes.test.js
diff --git a/integration_tests/__tests__/config-test.js b/integration_tests/__tests__/config.test.js
similarity index 100%
rename from integration_tests/__tests__/config-test.js
rename to integration_tests/__tests__/config.test.js
diff --git a/integration_tests/__tests__/console-test.js b/integration_tests/__tests__/console.test.js
similarity index 100%
rename from integration_tests/__tests__/console-test.js
rename to integration_tests/__tests__/console.test.js
diff --git a/integration_tests/__tests__/coverage-remapping-test.js b/integration_tests/__tests__/coverage_remapping.test.js
similarity index 100%
rename from integration_tests/__tests__/coverage-remapping-test.js
rename to integration_tests/__tests__/coverage_remapping.test.js
diff --git a/integration_tests/__tests__/coverage_report-test.js b/integration_tests/__tests__/coverage_report.test.js
similarity index 99%
rename from integration_tests/__tests__/coverage_report-test.js
rename to integration_tests/__tests__/coverage_report.test.js
index 3ae2a89be840..21a406a20156 100644
--- a/integration_tests/__tests__/coverage_report-test.js
+++ b/integration_tests/__tests__/coverage_report.test.js
@@ -57,7 +57,7 @@ test('collects coverage only from specified files avoiding dependencies', () =>
     '--collectCoverageOnlyFrom',
     'sum.js',
     '--',
-    'sum-test.js',
+    'sum.test.js',
   ]);
 
   // Coverage report should only have `sum.js` coverage info
diff --git a/integration_tests/__tests__/coverage-threshold-test.js b/integration_tests/__tests__/coverage_threshold.test.js
similarity index 100%
rename from integration_tests/__tests__/coverage-threshold-test.js
rename to integration_tests/__tests__/coverage_threshold.test.js
diff --git a/integration_tests/__tests__/custom-reporters-test.js b/integration_tests/__tests__/custom_reporters.test.js
similarity index 85%
rename from integration_tests/__tests__/custom-reporters-test.js
rename to integration_tests/__tests__/custom_reporters.test.js
index 2e57e3301161..6b41da7107b8 100644
--- a/integration_tests/__tests__/custom-reporters-test.js
+++ b/integration_tests/__tests__/custom_reporters.test.js
@@ -16,13 +16,13 @@ describe('Custom Reporters Integration', () => {
 
   test('valid string format for adding reporters', () => {
     const reporterConfig = {
-      reporters: ['<rootDir>/reporters/TestReporter.js'],
+      reporters: ['<rootDir>/reporters/test_reporter.js'],
     };
 
     const {status} = runJest('custom_reporters', [
       '--config',
       JSON.stringify(reporterConfig),
-      'add-test.js',
+      'add.test.js',
     ]);
 
     expect(status).toBe(0);
@@ -31,14 +31,17 @@ describe('Custom Reporters Integration', () => {
   test('valid array format for adding reporters', () => {
     const reporterConfig = {
       reporters: [
-        ['<rootDir>/reporters/TestReporter.js', {'Dmitrii Abramov': 'Awesome'}],
+        [
+          '<rootDir>/reporters/test_reporter.js',
+          {'Dmitrii Abramov': 'Awesome'},
+        ],
       ],
     };
 
     const {status} = runJest('custom_reporters', [
       '--config',
       JSON.stringify(reporterConfig),
-      'add-test.js',
+      'add.test.js',
     ]);
 
     expect(status).toBe(0);
@@ -52,7 +55,7 @@ describe('Custom Reporters Integration', () => {
     const {status, stderr} = runJest('custom_reporters', [
       '--config',
       JSON.stringify(reporterConfig),
-      'add-test.js',
+      'add.test.js',
     ]);
 
     expect(status).toBe(1);
@@ -63,9 +66,9 @@ describe('Custom Reporters Integration', () => {
     const {stderr, stdout, status} = runJest('custom_reporters', [
       '--config',
       JSON.stringify({
-        reporters: ['default', '<rootDir>/reporters/TestReporter.js'],
+        reporters: ['default', '<rootDir>/reporters/test_reporter.js'],
       }),
-      'add-test.js',
+      'add.test.js',
     ]);
 
     const {summary, rest} = extractSummary(stderr);
@@ -79,7 +82,7 @@ describe('Custom Reporters Integration', () => {
 
   test('TestReporter with all tests passing', () => {
     const {stdout, status, stderr} = runJest('custom_reporters', [
-      'add-test.js',
+      'add.test.js',
     ]);
 
     const parsedJSON = JSON.parse(stdout);
@@ -91,7 +94,7 @@ describe('Custom Reporters Integration', () => {
 
   test('TestReporter with all tests failing', () => {
     const {stdout, status, stderr} = runJest('custom_reporters', [
-      'add-fail-test.js',
+      'add_fail.test.js',
     ]);
 
     const parsedJSON = JSON.parse(stdout);
@@ -106,9 +109,9 @@ describe('Custom Reporters Integration', () => {
       '--no-cache',
       '--config',
       JSON.stringify({
-        reporters: ['<rootDir>/reporters/IncompleteReporter.js'],
+        reporters: ['<rootDir>/reporters/incomplete_reporter.js'],
       }),
-      'add-test.js',
+      'add.test.js',
     ]);
 
     expect(status).toBe(0);
diff --git a/integration_tests/__tests__/debug-test.js b/integration_tests/__tests__/debug.test.js
similarity index 100%
rename from integration_tests/__tests__/debug-test.js
rename to integration_tests/__tests__/debug.test.js
diff --git a/integration_tests/__tests__/empty_suite_error-test.js b/integration_tests/__tests__/empty_suite_error.test.js
similarity index 100%
rename from integration_tests/__tests__/empty_suite_error-test.js
rename to integration_tests/__tests__/empty_suite_error.test.js
diff --git a/integration_tests/__tests__/env-test.js b/integration_tests/__tests__/env.test.js
similarity index 100%
rename from integration_tests/__tests__/env-test.js
rename to integration_tests/__tests__/env.test.js
diff --git a/integration_tests/__tests__/failures-test.js b/integration_tests/__tests__/failures.test.js
similarity index 84%
rename from integration_tests/__tests__/failures-test.js
rename to integration_tests/__tests__/failures.test.js
index 46049519b11b..d878126be122 100644
--- a/integration_tests/__tests__/failures-test.js
+++ b/integration_tests/__tests__/failures.test.js
@@ -43,17 +43,17 @@ const cleanupStackTrace = stderr => {
 
 test('not throwing Error objects', () => {
   let stderr;
-  stderr = runJest(dir, ['throw-number-test.js']).stderr;
+  stderr = runJest(dir, ['throw_number.test.js']).stderr;
   expect(extractSummary(stderr).rest).toMatchSnapshot();
-  stderr = runJest(dir, ['throw-string-test.js']).stderr;
+  stderr = runJest(dir, ['throw_string.test.js']).stderr;
   expect(extractSummary(stderr).rest).toMatchSnapshot();
-  stderr = runJest(dir, ['throw-object-test.js']).stderr;
+  stderr = runJest(dir, ['throw_object.test.js']).stderr;
   expect(extractSummary(stderr).rest).toMatchSnapshot();
-  stderr = runJest(dir, ['assertion-count-test.js']).stderr;
+  stderr = runJest(dir, ['assertion_count.test.js']).stderr;
   expect(extractSummary(cleanupStackTrace(stderr)).rest).toMatchSnapshot();
 });
 
 test('works with node assert', () => {
-  const {stderr} = runJest(dir, ['node-assertion-error-test.js']);
+  const {stderr} = runJest(dir, ['node_assertion_error.test.js']);
   expect(normalizeDots(extractSummary(stderr).rest)).toMatchSnapshot();
 });
diff --git a/integration_tests/__tests__/global-test.js b/integration_tests/__tests__/global.test.js
similarity index 100%
rename from integration_tests/__tests__/global-test.js
rename to integration_tests/__tests__/global.test.js
diff --git a/integration_tests/__tests__/globals-test.js b/integration_tests/__tests__/globals.test.js
similarity index 92%
rename from integration_tests/__tests__/globals-test.js
rename to integration_tests/__tests__/globals.test.js
index 8471d4b8dd16..4735fe673b6d 100644
--- a/integration_tests/__tests__/globals-test.js
+++ b/integration_tests/__tests__/globals.test.js
@@ -15,7 +15,7 @@ const runJest = require('../runJest');
 const {extractSummary} = require('../utils');
 const {createEmptyPackage, writeFiles, cleanup} = require('../utils');
 
-const DIR = path.resolve(os.tmpdir(), 'global-variables-test');
+const DIR = path.resolve(os.tmpdir(), 'global-variables.test');
 const TEST_DIR = path.resolve(DIR, '__tests__');
 
 skipOnWindows.suite();
@@ -28,7 +28,7 @@ beforeEach(() => {
 afterAll(() => cleanup(DIR));
 
 test('basic test constructs', () => {
-  const filename = 'basic-test-constructs-test.js';
+  const filename = 'basic.test-constructs.test.js';
   const content = `
     it('it', () => {});
     test('test', () => {});
@@ -49,7 +49,7 @@ test('basic test constructs', () => {
 });
 
 test('skips', () => {
-  const filename = 'skips-constructs-test.js';
+  const filename = 'skips-constructs.test.js';
   const content = `
     it('it', () => {});
     xtest('xtest', () => {});
@@ -80,7 +80,7 @@ test('skips', () => {
 });
 
 test('only', () => {
-  const filename = 'only-constructs-test.js';
+  const filename = 'only-constructs.test.js';
   const content = `
     it('it', () => {});
     test.only('test.only', () => {});
@@ -110,7 +110,7 @@ test('only', () => {
 });
 
 test('tests with no implementation', () => {
-  const filename = 'only-constructs-test.js';
+  const filename = 'only-constructs.test.js';
   const content = `
     it('it', () => {});
     it('it, no implementation');
@@ -127,7 +127,7 @@ test('tests with no implementation', () => {
 });
 
 test('skips with expand arg', () => {
-  const filename = 'skips-constructs-test.js';
+  const filename = 'skips-constructs.test.js';
   const content = `
     it('it', () => {});
     xtest('xtest', () => {});
@@ -158,7 +158,7 @@ test('skips with expand arg', () => {
 });
 
 test('only with expand arg', () => {
-  const filename = 'only-constructs-test.js';
+  const filename = 'only-constructs.test.js';
   const content = `
     it('it', () => {});
     test.only('test.only', () => {});
@@ -188,7 +188,7 @@ test('only with expand arg', () => {
 });
 
 test('tests with no implementation with expand arg', () => {
-  const filename = 'only-constructs-test.js';
+  const filename = 'only-constructs.test.js';
   const content = `
     it('it', () => {});
     it('it, no implementation');
diff --git a/integration_tests/__tests__/jasmine_async-test.js b/integration_tests/__tests__/jasmine_async.test.js
similarity index 87%
rename from integration_tests/__tests__/jasmine_async-test.js
rename to integration_tests/__tests__/jasmine_async.test.js
index aed80cbb68f2..69654fea1cf3 100644
--- a/integration_tests/__tests__/jasmine_async-test.js
+++ b/integration_tests/__tests__/jasmine_async.test.js
@@ -12,7 +12,9 @@ const runJest = require('../runJest');
 
 describe('async jasmine', () => {
   it('works with beforeAll', () => {
-    const result = runJest.json('jasmine_async', ['promise_beforeAll-test.js']);
+    const result = runJest.json('jasmine_async', [
+      'promise_before_all.test.js',
+    ]);
     const json = result.json;
 
     expect(json.numTotalTests).toBe(2);
@@ -27,7 +29,7 @@ describe('async jasmine', () => {
 
   it('works with beforeEach', () => {
     const result = runJest.json('jasmine_async', [
-      'promise_beforeEach-test.js',
+      'promise_before_each.test.js',
     ]);
     const json = result.json;
 
@@ -39,7 +41,7 @@ describe('async jasmine', () => {
   });
 
   it('works with afterAll', () => {
-    const result = runJest.json('jasmine_async', ['promise_afterAll-test.js']);
+    const result = runJest.json('jasmine_async', ['promise_after_all.test.js']);
     const json = result.json;
 
     expect(json.numTotalTests).toBe(2);
@@ -52,7 +54,9 @@ describe('async jasmine', () => {
   });
 
   it('works with afterEach', () => {
-    const result = runJest.json('jasmine_async', ['promise_afterEach-test.js']);
+    const result = runJest.json('jasmine_async', [
+      'promise_after_each.test.js',
+    ]);
     const json = result.json;
 
     expect(json.numTotalTests).toBe(2);
@@ -63,7 +67,7 @@ describe('async jasmine', () => {
   });
 
   it('works with fit', () => {
-    const result = runJest.json('jasmine_async', ['promise_fit-test.js']);
+    const result = runJest.json('jasmine_async', ['promise_fit.test.js']);
     const json = result.json;
 
     expect(json.numTotalTests).toBe(3);
@@ -74,7 +78,7 @@ describe('async jasmine', () => {
   });
 
   it('works with xit', () => {
-    const result = runJest.json('jasmine_async', ['promise_xit-test.js']);
+    const result = runJest.json('jasmine_async', ['promise_xit.test.js']);
     const json = result.json;
 
     expect(json.numTotalTests).toBe(2);
@@ -84,7 +88,7 @@ describe('async jasmine', () => {
   });
 
   it('throws when not a promise is returned', () => {
-    const result = runJest.json('jasmine_async', ['returning_values-test.js']);
+    const result = runJest.json('jasmine_async', ['returning_values.test.js']);
     const json = result.json;
 
     expect(json.numTotalTests).toBe(11);
@@ -94,7 +98,7 @@ describe('async jasmine', () => {
   });
 
   it('tests async promise code', () => {
-    const result = runJest.json('jasmine_async', ['promise_it-test.js']);
+    const result = runJest.json('jasmine_async', ['promise_it.test.js']);
     const json = result.json;
     const message = json.testResults[0].message;
 
@@ -109,7 +113,7 @@ describe('async jasmine', () => {
   });
 
   it('works with concurrent', () => {
-    const result = runJest.json('jasmine_async', ['concurrent-test.js']);
+    const result = runJest.json('jasmine_async', ['concurrent.test.js']);
     const json = result.json;
     expect(json.numTotalTests).toBe(4);
     expect(json.numPassedTests).toBe(2);
diff --git a/integration_tests/__tests__/jest.config.js-test.js b/integration_tests/__tests__/jest.config.js.test.js
similarity index 100%
rename from integration_tests/__tests__/jest.config.js-test.js
rename to integration_tests/__tests__/jest.config.js.test.js
diff --git a/integration_tests/__tests__/json-test.js b/integration_tests/__tests__/json.test.js
similarity index 100%
rename from integration_tests/__tests__/json-test.js
rename to integration_tests/__tests__/json.test.js
diff --git a/integration_tests/__tests__/json_reporter-test.js b/integration_tests/__tests__/json_reporter.test.js
similarity index 100%
rename from integration_tests/__tests__/json_reporter-test.js
rename to integration_tests/__tests__/json_reporter.test.js
diff --git a/integration_tests/__tests__/list_tests-test.js b/integration_tests/__tests__/list_tests.test.js
similarity index 100%
rename from integration_tests/__tests__/list_tests-test.js
rename to integration_tests/__tests__/list_tests.test.js
diff --git a/integration_tests/__tests__/native-async-mock-test.js b/integration_tests/__tests__/native_async_mock.test.js
similarity index 100%
rename from integration_tests/__tests__/native-async-mock-test.js
rename to integration_tests/__tests__/native_async_mock.test.js
diff --git a/integration_tests/__tests__/no-test-found-test.js b/integration_tests/__tests__/no_test_found.test.js
similarity index 100%
rename from integration_tests/__tests__/no-test-found-test.js
rename to integration_tests/__tests__/no_test_found.test.js
diff --git a/integration_tests/__tests__/node_path-test.js b/integration_tests/__tests__/node_path.test.js
similarity index 100%
rename from integration_tests/__tests__/node_path-test.js
rename to integration_tests/__tests__/node_path.test.js
diff --git a/integration_tests/__tests__/regex-(char-in-path-test.js b/integration_tests/__tests__/regex_(char_in_path.test.js
similarity index 100%
rename from integration_tests/__tests__/regex-(char-in-path-test.js
rename to integration_tests/__tests__/regex_(char_in_path.test.js
diff --git a/integration_tests/__tests__/require-v8-module-test.js b/integration_tests/__tests__/require_v8_module.test.js
similarity index 100%
rename from integration_tests/__tests__/require-v8-module-test.js
rename to integration_tests/__tests__/require_v8_module.test.js
diff --git a/integration_tests/__tests__/resolve-test.js b/integration_tests/__tests__/resolve.test.js
similarity index 100%
rename from integration_tests/__tests__/resolve-test.js
rename to integration_tests/__tests__/resolve.test.js
diff --git a/integration_tests/__tests__/runtime-internal-module-registry-test.js b/integration_tests/__tests__/runtime_internal_module_registry.test.js
similarity index 100%
rename from integration_tests/__tests__/runtime-internal-module-registry-test.js
rename to integration_tests/__tests__/runtime_internal_module_registry.test.js
diff --git a/integration_tests/__tests__/set-immediate-test.js b/integration_tests/__tests__/set_immediate.test.js
similarity index 100%
rename from integration_tests/__tests__/set-immediate-test.js
rename to integration_tests/__tests__/set_immediate.test.js
diff --git a/integration_tests/__tests__/setup_test_framework_script_file_cli_config-test.js b/integration_tests/__tests__/setup_test_framework_script_file_cli_config.test.js
similarity index 94%
rename from integration_tests/__tests__/setup_test_framework_script_file_cli_config-test.js
rename to integration_tests/__tests__/setup_test_framework_script_file_cli_config.test.js
index 54075f3d0a85..ce8c53924951 100644
--- a/integration_tests/__tests__/setup_test_framework_script_file_cli_config-test.js
+++ b/integration_tests/__tests__/setup_test_framework_script_file_cli_config.test.js
@@ -14,8 +14,8 @@ describe('--setupTestFrameworkScriptFile setup.js', () => {
     const result = runJest.json('setup_test_framework_script_file_cli_config', [
       '--setupTestFrameworkScriptFile',
       './setup1.js',
-      'test1-test.js',
-      'test2-test.js',
+      'test1.test.js',
+      'test2.test.js',
     ]);
 
     expect(result.status).toBe(0);
@@ -28,7 +28,7 @@ describe('--setupTestFrameworkScriptFile setup.js', () => {
     const result = runJest.json('setup_test_framework_script_file_cli_config', [
       '--setupTestFrameworkScriptFile',
       './setup_hooks_into_runner.js',
-      'runner_patch-test.js',
+      'runner_patch.test.js',
     ]);
 
     expect(result.json.numTotalTests).toBe(1);
diff --git a/integration_tests/__tests__/showConfig-test.js b/integration_tests/__tests__/show_config.test.js
similarity index 100%
rename from integration_tests/__tests__/showConfig-test.js
rename to integration_tests/__tests__/show_config.test.js
diff --git a/integration_tests/__tests__/snapshot-test.js b/integration_tests/__tests__/snapshot.test.js
similarity index 94%
rename from integration_tests/__tests__/snapshot-test.js
rename to integration_tests/__tests__/snapshot.test.js
index f25a15ac72fc..d53faf06a215 100644
--- a/integration_tests/__tests__/snapshot-test.js
+++ b/integration_tests/__tests__/snapshot.test.js
@@ -19,15 +19,15 @@ const snapshotDir = path.resolve(
   __dirname,
   '../snapshot/__tests__/__snapshots__',
 );
-const snapshotFile = path.resolve(snapshotDir, 'snapshot-test.js.snap');
+const snapshotFile = path.resolve(snapshotDir, 'snapshot.test.js.snap');
 const secondSnapshotFile = path.resolve(
   snapshotDir,
-  'second-snapshot-test.js.snap',
+  'second_snapshot.test.js.snap',
 );
-const snapshotOfCopy = path.resolve(snapshotDir, 'snapshot-test_copy.js.snap');
+const snapshotOfCopy = path.resolve(snapshotDir, 'snapshot.test_copy.js.snap');
 const originalTestPath = path.resolve(
   __dirname,
-  '../snapshot/__tests__/snapshot-test.js',
+  '../snapshot/__tests__/snapshot.test.js',
 );
 const originalTestContent = fs.readFileSync(originalTestPath, 'utf8');
 const copyOfTestPath = originalTestPath.replace('.js', '_copy.js');
@@ -38,7 +38,7 @@ const snapshotEscapeDir = path.resolve(
 );
 const snapshotEscapeTestFile = path.resolve(
   snapshotEscapeDir,
-  'snapshot-test.js',
+  'snapshot.test.js',
 );
 const snapshotEscapeSnapshotDir = path.resolve(
   snapshotEscapeDir,
@@ -46,15 +46,15 @@ const snapshotEscapeSnapshotDir = path.resolve(
 );
 const snapshotEscapeFile = path.resolve(
   snapshotEscapeSnapshotDir,
-  'snapshot-test.js.snap',
+  'snapshot.test.js.snap',
 );
 const snapshotEscapeRegexFile = path.resolve(
   snapshotEscapeSnapshotDir,
-  'snapshot-escape-regex.js.snap',
+  'snapshot_escape_regex.js.snap',
 );
 const snapshotEscapeSubstitutionFile = path.resolve(
   snapshotEscapeSnapshotDir,
-  'snapshot-escape-substitution-test.js.snap',
+  'snapshot_escape_substitution.test.js.snap',
 );
 
 const initialTestData = fs.readFileSync(snapshotEscapeTestFile, 'utf8');
@@ -125,7 +125,7 @@ describe('Snapshot', () => {
     let result = runJest('snapshot-escape', [
       '-w=1',
       '--ci=false',
-      'snapshot-test.js',
+      'snapshot.test.js',
     ]);
     let stderr = result.stderr.toString();
 
@@ -144,7 +144,7 @@ describe('Snapshot', () => {
       '-w=1',
       '--ci=false',
       '--updateSnapshot',
-      'snapshot-test.js',
+      'snapshot.test.js',
     ]);
     stderr = result.stderr.toString();
 
@@ -157,7 +157,7 @@ describe('Snapshot', () => {
     result = runJest('snapshot-escape', [
       '-w=1',
       '--ci=false',
-      'snapshot-test.js',
+      'snapshot.test.js',
     ]);
     stderr = result.stderr.toString();
 
@@ -171,7 +171,7 @@ describe('Snapshot', () => {
     let result = runJest('snapshot-escape', [
       '-w=1',
       '--ci=false',
-      'snapshot-escape-regex.js',
+      'snapshot_escape_regex.js',
     ]);
     let stderr = result.stderr.toString();
 
@@ -182,7 +182,7 @@ describe('Snapshot', () => {
     result = runJest('snapshot-escape', [
       '-w=1',
       '--ci=false',
-      'snapshot-escape-regex.js',
+      'snapshot_escape_regex.js',
     ]);
     stderr = result.stderr.toString();
 
@@ -198,7 +198,7 @@ describe('Snapshot', () => {
     let result = runJest('snapshot-escape', [
       '-w=1',
       '--ci=false',
-      'snapshot-escape-substitution-test.js',
+      'snapshot_escape_substitution.test.js',
     ]);
     let stderr = result.stderr.toString();
 
@@ -209,7 +209,7 @@ describe('Snapshot', () => {
     result = runJest('snapshot-escape', [
       '-w=1',
       '--ci=false',
-      'snapshot-escape-substitution-test.js',
+      'snapshot_escape_substitution.test.js',
     ]);
     stderr = result.stderr.toString();
 
diff --git a/integration_tests/__tests__/snapshot-serializers-test.js b/integration_tests/__tests__/snapshot_serializers.test.js
similarity index 95%
rename from integration_tests/__tests__/snapshot-serializers-test.js
rename to integration_tests/__tests__/snapshot_serializers.test.js
index de6a03a2559e..42d98d55e6f0 100644
--- a/integration_tests/__tests__/snapshot-serializers-test.js
+++ b/integration_tests/__tests__/snapshot_serializers.test.js
@@ -14,7 +14,7 @@ const runJest = require('../runJest');
 
 const testDir = path.resolve(__dirname, '../snapshot-serializers');
 const snapshotsDir = path.resolve(testDir, '__tests__/__snapshots__');
-const snapshotPath = path.resolve(snapshotsDir, 'snapshot-test.js.snap');
+const snapshotPath = path.resolve(snapshotsDir, 'snapshot.test.js.snap');
 
 const runAndAssert = () => {
   const result = runJest.json('snapshot-serializers', [
diff --git a/integration_tests/__tests__/stack_trace-test.js b/integration_tests/__tests__/stack_trace.test.js
similarity index 79%
rename from integration_tests/__tests__/stack_trace-test.js
rename to integration_tests/__tests__/stack_trace.test.js
index ad428c62a55c..f64cf6dc5e81 100644
--- a/integration_tests/__tests__/stack_trace-test.js
+++ b/integration_tests/__tests__/stack_trace.test.js
@@ -12,7 +12,7 @@ const {extractSummary} = require('../utils');
 
 describe('Stack Trace', () => {
   it('prints a stack trace for runtime errors', () => {
-    const result = runJest('stack_trace', ['runtime-error-test.js']);
+    const result = runJest('stack_trace', ['runtime_error.test.js']);
     const stderr = result.stderr.toString();
 
     expect(extractSummary(stderr).summary).toMatchSnapshot();
@@ -22,13 +22,13 @@ describe('Stack Trace', () => {
       /ReferenceError: thisIsARuntimeError is not defined/,
     );
     expect(stderr).toMatch(
-      /\s+at\s(?:.+?)\s\(__tests__\/runtime-error-test\.js/,
+      /\s+at\s(?:.+?)\s\(__tests__\/runtime_error.test\.js/,
     );
   });
 
   it('does not print a stack trace for runtime errors when --noStackTrace is given', () => {
     const result = runJest('stack_trace', [
-      'runtime-error-test.js',
+      'runtime_error.test.js',
       '--noStackTrace',
     ]);
     const stderr = result.stderr.toString();
@@ -40,23 +40,23 @@ describe('Stack Trace', () => {
       /ReferenceError: thisIsARuntimeError is not defined/,
     );
     expect(stderr).not.toMatch(
-      /\s+at\s(?:.+?)\s\(__tests__\/runtime-error-test\.js/,
+      /\s+at\s(?:.+?)\s\(__tests__\/runtime_error.test\.js/,
     );
   });
 
   it('prints a stack trace for matching errors', () => {
-    const result = runJest('stack_trace', ['stack-trace-test.js']);
+    const result = runJest('stack_trace', ['stack_trace.test.js']);
     const stderr = result.stderr.toString();
 
     expect(extractSummary(stderr).summary).toMatchSnapshot();
     expect(result.status).toBe(1);
 
-    expect(stderr).toMatch(/\s+at\s(?:.+?)\s\(__tests__\/stack-trace-test\.js/);
+    expect(stderr).toMatch(/\s+at\s(?:.+?)\s\(__tests__\/stack_trace.test\.js/);
   });
 
   it('does not print a stack trace for matching errors when --noStackTrace is given', () => {
     const result = runJest('stack_trace', [
-      'stack-trace-test.js',
+      'stack_trace.test.js',
       '--noStackTrace',
     ]);
     const stderr = result.stderr.toString();
@@ -65,12 +65,12 @@ describe('Stack Trace', () => {
     expect(result.status).toBe(1);
 
     expect(stderr).not.toMatch(
-      /\s+at\s(?:.+?)\s\(__tests__\/stack-trace-test\.js/,
+      /\s+at\s(?:.+?)\s\(__tests__\/stack_trace.test\.js/,
     );
   });
 
   it('prints a stack trace for errors', () => {
-    const result = runJest('stack_trace', ['test-error-test.js']);
+    const result = runJest('stack_trace', ['test_error.test.js']);
     const stderr = result.stderr.toString();
 
     expect(extractSummary(stderr).summary).toMatchSnapshot();
@@ -79,11 +79,11 @@ describe('Stack Trace', () => {
     expect(stderr).toMatch(/this is unexpected\./);
     expect(stderr).toMatch(/this is a string\. thrown/);
 
-    expect(stderr).toMatch(/\s+at\s(?:.+?)\s\(__tests__\/test-error-test\.js/);
+    expect(stderr).toMatch(/\s+at\s(?:.+?)\s\(__tests__\/test_error.test\.js/);
 
     // Make sure we show Jest's jest-resolve as part of the stack trace
     expect(stderr).toMatch(
-      /Cannot find module 'this-module-does-not-exist' from 'test-error-test\.js'/,
+      /Cannot find module 'this-module-does-not-exist' from 'test_error.test\.js'/,
     );
 
     expect(stderr).toMatch(
@@ -93,7 +93,7 @@ describe('Stack Trace', () => {
 
   it('prints a stack trace for errors without message in stack trace', () => {
     const result = runJest('stack_trace', [
-      'stack-trace-without-message-test.js',
+      'stack_trace_without_message.test.js',
     ]);
     const stderr = result.stderr.toString();
 
@@ -102,13 +102,13 @@ describe('Stack Trace', () => {
 
     expect(stderr).toMatch(/important message/);
     expect(stderr).toMatch(
-      /\s+at\s(?:.+?)\s\(__tests__\/stack-trace-without-message-test\.js/,
+      /\s+at\s(?:.+?)\s\(__tests__\/stack_trace_without_message.test\.js/,
     );
   });
 
   it('does not print a stack trace for errors when --noStackTrace is given', () => {
     const result = runJest('stack_trace', [
-      'test-error-test.js',
+      'test_error.test.js',
       '--noStackTrace',
     ]);
     const stderr = result.stderr.toString();
@@ -117,7 +117,7 @@ describe('Stack Trace', () => {
     expect(result.status).toBe(1);
 
     expect(stderr).not.toMatch(
-      /\s+at\s(?:.+?)\s\(__tests__\/test-error-test\.js/,
+      /\s+at\s(?:.+?)\s\(__tests__\/test_error.test\.js/,
     );
   });
 });
diff --git a/integration_tests/__tests__/symbol-test.js b/integration_tests/__tests__/symbol.test.js
similarity index 100%
rename from integration_tests/__tests__/symbol-test.js
rename to integration_tests/__tests__/symbol.test.js
diff --git a/integration_tests/__tests__/test-environment-test.js b/integration_tests/__tests__/test_environment.test.js
similarity index 100%
rename from integration_tests/__tests__/test-environment-test.js
rename to integration_tests/__tests__/test_environment.test.js
diff --git a/integration_tests/__tests__/test-in-root-test.js b/integration_tests/__tests__/test_in_root.test.js
similarity index 100%
rename from integration_tests/__tests__/test-in-root-test.js
rename to integration_tests/__tests__/test_in_root.test.js
diff --git a/integration_tests/__tests__/testNamePattern-test.js b/integration_tests/__tests__/test_name_pattern.test.js
similarity index 100%
rename from integration_tests/__tests__/testNamePattern-test.js
rename to integration_tests/__tests__/test_name_pattern.test.js
diff --git a/integration_tests/__tests__/testResultsProcessor-test.js b/integration_tests/__tests__/test_results_processor.test.js
similarity index 100%
rename from integration_tests/__tests__/testResultsProcessor-test.js
rename to integration_tests/__tests__/test_results_processor.test.js
diff --git a/integration_tests/__tests__/timeouts-test.js b/integration_tests/__tests__/timeouts.test.js
similarity index 100%
rename from integration_tests/__tests__/timeouts-test.js
rename to integration_tests/__tests__/timeouts.test.js
diff --git a/integration_tests/__tests__/timer-resetMocks-test.js b/integration_tests/__tests__/timer_reset_mocks.test.js
similarity index 100%
rename from integration_tests/__tests__/timer-resetMocks-test.js
rename to integration_tests/__tests__/timer_reset_mocks.test.js
diff --git a/integration_tests/__tests__/timer-useRealTimers-test.js b/integration_tests/__tests__/timer_use_real_timers.test.js
similarity index 91%
rename from integration_tests/__tests__/timer-useRealTimers-test.js
rename to integration_tests/__tests__/timer_use_real_timers.test.js
index 9116f0d5e603..e1a450b0d686 100644
--- a/integration_tests/__tests__/timer-useRealTimers-test.js
+++ b/integration_tests/__tests__/timer_use_real_timers.test.js
@@ -12,7 +12,7 @@
 const runJest = require('../runJest');
 
 test('useRealTimers cancels "timers": "fake" for whole test file', () => {
-  const result = runJest('timer-useRealTimers');
+  const result = runJest('timer_use_real_timers');
   expect(result.stdout).toMatch('API is not mocked with fake timers.');
   expect(result.status).toBe(0);
 });
diff --git a/integration_tests/__tests__/toMatchSnapshot-test.js b/integration_tests/__tests__/to_match_snapshot.test.js
similarity index 93%
rename from integration_tests/__tests__/toMatchSnapshot-test.js
rename to integration_tests/__tests__/to_match_snapshot.test.js
index c1d683035328..d54359c45afe 100644
--- a/integration_tests/__tests__/toMatchSnapshot-test.js
+++ b/integration_tests/__tests__/to_match_snapshot.test.js
@@ -17,7 +17,7 @@ beforeEach(() => cleanup(TESTS_DIR));
 afterAll(() => cleanup(TESTS_DIR));
 
 test('basic support', () => {
-  const filename = 'basic-support-test.js';
+  const filename = 'basic-support.test.js';
   const template = makeTemplate(
     `test('snapshots', () => expect($1).toMatchSnapshot());`,
   );
@@ -40,7 +40,7 @@ test('basic support', () => {
 
   // This test below also covers how jest-editor-support creates terse messages
   // for letting a Snapshot update, so if the wording is updated, please edit
-  // /packages/jest-editor-support/src/TestReconciler.js
+  // /packages/jest-editor-support/src/test_reconciler.js
   {
     writeFiles(TESTS_DIR, {
       [filename]: template(['{apple: "updated value"}']),
@@ -63,7 +63,7 @@ test('basic support', () => {
 });
 
 test('error thrown before snapshot', () => {
-  const filename = 'error-thrown-before-snapshot-test.js';
+  const filename = 'error-thrown-before-snapshot.test.js';
   const template = makeTemplate(`test('snapshots', () => {
       expect($1).toBeTruthy();
       expect($2).toMatchSnapshot();
@@ -95,7 +95,7 @@ test('error thrown before snapshot', () => {
 });
 
 test('first snapshot fails, second passes', () => {
-  const filename = 'first-snapshot-fails-second-passes-test.js';
+  const filename = 'first-snapshot-fails-second-passes.test.js';
   const template = makeTemplate(`test('snapshots', () => {
       expect($1).toMatchSnapshot();
       expect($2).toMatchSnapshot();
@@ -119,7 +119,7 @@ test('first snapshot fails, second passes', () => {
 });
 
 test('does not mark snapshots as obsolete in skipped tests', () => {
-  const filename = 'no-obsolete-if-skipped-test.js';
+  const filename = 'no-obsolete-if-skipped.test.js';
   const template = makeTemplate(`test('snapshots', () => {
       expect(true).toBe(true);
     });
@@ -145,7 +145,7 @@ test('does not mark snapshots as obsolete in skipped tests', () => {
 });
 
 test('accepts custom snapshot name', () => {
-  const filename = 'accept-custom-snapshot-name-test.js';
+  const filename = 'accept-custom-snapshot-name.test.js';
   const template = makeTemplate(`test('accepts custom snapshot name', () => {
       expect(true).toMatchSnapshot('custom-name');
     });
diff --git a/integration_tests/__tests__/toThrowErrorMatchingSnapshot-test.js b/integration_tests/__tests__/to_throw_error_matching_snapshot.test.js
similarity index 91%
rename from integration_tests/__tests__/toThrowErrorMatchingSnapshot-test.js
rename to integration_tests/__tests__/to_throw_error_matching_snapshot.test.js
index 9ae48ab06600..86749f66af5e 100644
--- a/integration_tests/__tests__/toThrowErrorMatchingSnapshot-test.js
+++ b/integration_tests/__tests__/to_throw_error_matching_snapshot.test.js
@@ -17,7 +17,7 @@ beforeEach(() => cleanup(TESTS_DIR));
 afterAll(() => cleanup(TESTS_DIR));
 
 test('works fine when function throws error', () => {
-  const filename = 'works-fine-when-function-throws-error-test.js';
+  const filename = 'works-fine-when-function-throws-error.test.js';
   const template = makeTemplate(`test('works fine when function throws error', () => {
        expect(() => { throw new Error('apple'); })
          .toThrowErrorMatchingSnapshot();
@@ -33,7 +33,7 @@ test('works fine when function throws error', () => {
 });
 
 test(`throws the error if tested function didn't throw error`, () => {
-  const filename = 'throws-if-tested-function-did-not-throw-test.js';
+  const filename = 'throws-if-tested-function-did-not-throw.test.js';
   const template = makeTemplate(`test('throws the error if tested function did not throw error', () => {
       expect(() => {}).toThrowErrorMatchingSnapshot();
     });
@@ -48,7 +48,7 @@ test(`throws the error if tested function didn't throw error`, () => {
 });
 
 test('does not accept arguments', () => {
-  const filename = 'does-not-accept-arguments-test.js';
+  const filename = 'does-not-accept-arguments.test.js';
   const template = makeTemplate(`test('does not accept arguments', () => {
       expect(() => { throw new Error('apple'); })
         .toThrowErrorMatchingSnapshot('foobar');
@@ -64,7 +64,7 @@ test('does not accept arguments', () => {
 });
 
 test('cannot be used with .not', () => {
-  const filename = 'cannot-be-used-with-not-test.js';
+  const filename = 'cannot-be-used-with-not.test.js';
   const template = makeTemplate(`test('cannot be used with .not', () => {
        expect('').not.toThrowErrorMatchingSnapshot();
     });
diff --git a/integration_tests/__tests__/transform-test.js b/integration_tests/__tests__/transform.test.js
similarity index 92%
rename from integration_tests/__tests__/transform-test.js
rename to integration_tests/__tests__/transform.test.js
index b2e7d69f472a..b4aded1db966 100644
--- a/integration_tests/__tests__/transform-test.js
+++ b/integration_tests/__tests__/transform.test.js
@@ -32,8 +32,8 @@ describe('babel-jest', () => {
   it('instruments only specific files and collects coverage', () => {
     const {stdout} = runJest(dir, ['--coverage', '--no-cache']);
     expect(stdout).toMatch('covered.js');
-    expect(stdout).not.toMatch('not-covered.js');
-    expect(stdout).not.toMatch('excluded-from-coverage.js');
+    expect(stdout).not.toMatch('not_covered.js');
+    expect(stdout).not.toMatch('excluded_from_coverage.js');
     // coverage result should not change
     expect(stdout).toMatchSnapshot();
   });
@@ -44,14 +44,14 @@ describe('no babel-jest', () => {
 
   it('fails with syntax error on flow types', () => {
     const {stderr} = runJest(dir, ['--no-cache']);
-    expect(stderr).toMatch(/FAIL.*fails-with-syntax-error/);
+    expect(stderr).toMatch(/FAIL.*fails_with_syntax_error/);
     expect(stderr).toMatch('SyntaxError: Unexpected token :');
   });
 
   test('instrumentation with no babel-jest', () => {
     const {stdout} = runJest(dir, ['--no-cache', '--coverage']);
     expect(stdout).toMatch('covered.js');
-    expect(stdout).not.toMatch('excluded-from-coverage.js');
+    expect(stdout).not.toMatch('excluded_from_coverage.js');
     // coverage result should not change
     expect(stdout).toMatchSnapshot();
   });
diff --git a/integration_tests/__tests__/typescript-coverage-test.js b/integration_tests/__tests__/typescript_coverage.test.js
similarity index 100%
rename from integration_tests/__tests__/typescript-coverage-test.js
rename to integration_tests/__tests__/typescript_coverage.test.js
diff --git a/integration_tests/__tests__/verbose-test.js b/integration_tests/__tests__/verbose.test.js
similarity index 100%
rename from integration_tests/__tests__/verbose-test.js
rename to integration_tests/__tests__/verbose.test.js
diff --git a/integration_tests/babel-plugin-jest-hoist/__tests__/integration-test.js b/integration_tests/babel-plugin-jest-hoist/__tests__/integration.test.js
similarity index 100%
rename from integration_tests/babel-plugin-jest-hoist/__tests__/integration-test.js
rename to integration_tests/babel-plugin-jest-hoist/__tests__/integration.test.js
diff --git a/integration_tests/babel-plugin-jest-hoist/__tests__/integration-automock-off-test.js b/integration_tests/babel-plugin-jest-hoist/__tests__/integration_automock_off.test.js
similarity index 100%
rename from integration_tests/babel-plugin-jest-hoist/__tests__/integration-automock-off-test.js
rename to integration_tests/babel-plugin-jest-hoist/__tests__/integration_automock_off.test.js
diff --git a/integration_tests/console/__tests__/console-test.js b/integration_tests/console/__tests__/console.test.js
similarity index 100%
rename from integration_tests/console/__tests__/console-test.js
rename to integration_tests/console/__tests__/console.test.js
diff --git a/integration_tests/coverage_report/__tests__/sum-test.js b/integration_tests/coverage_report/__tests__/sum.test.js
similarity index 100%
rename from integration_tests/coverage_report/__tests__/sum-test.js
rename to integration_tests/coverage_report/__tests__/sum.test.js
diff --git a/integration_tests/custom_reporters/__tests__/add-test.js b/integration_tests/custom_reporters/__tests__/add.test.js
similarity index 100%
rename from integration_tests/custom_reporters/__tests__/add-test.js
rename to integration_tests/custom_reporters/__tests__/add.test.js
diff --git a/integration_tests/custom_reporters/__tests__/add-fail-test.js b/integration_tests/custom_reporters/__tests__/add_fail.test.js
similarity index 100%
rename from integration_tests/custom_reporters/__tests__/add-fail-test.js
rename to integration_tests/custom_reporters/__tests__/add_fail.test.js
diff --git a/integration_tests/custom_reporters/package.json b/integration_tests/custom_reporters/package.json
index 590f11ffe692..3c42adef4a3a 100644
--- a/integration_tests/custom_reporters/package.json
+++ b/integration_tests/custom_reporters/package.json
@@ -1,7 +1,7 @@
 {
   "jest": {
     "reporters": [
-      ["<rootDir>/reporters/TestReporter.js", {
+      ["<rootDir>/reporters/test_reporter.js", {
         "hello": "world",
         "dmitrii": "abramov",
         "christoph": "pojer"
diff --git a/integration_tests/custom_reporters/reporters/IncompleteReporter.js b/integration_tests/custom_reporters/reporters/incomplete_reporter.js
similarity index 100%
rename from integration_tests/custom_reporters/reporters/IncompleteReporter.js
rename to integration_tests/custom_reporters/reporters/incomplete_reporter.js
diff --git a/integration_tests/custom_reporters/reporters/TestReporter.js b/integration_tests/custom_reporters/reporters/test_reporter.js
similarity index 100%
rename from integration_tests/custom_reporters/reporters/TestReporter.js
rename to integration_tests/custom_reporters/reporters/test_reporter.js
diff --git a/integration_tests/empty_suite_error/__tests__/empty-suite-test.js b/integration_tests/empty_suite_error/__tests__/empty_suite.test.js
similarity index 100%
rename from integration_tests/empty_suite_error/__tests__/empty-suite-test.js
rename to integration_tests/empty_suite_error/__tests__/empty_suite.test.js
diff --git a/integration_tests/env-test/__tests__/env-test.js b/integration_tests/env-test/__tests__/env.test.js
similarity index 100%
rename from integration_tests/env-test/__tests__/env-test.js
rename to integration_tests/env-test/__tests__/env.test.js
diff --git a/integration_tests/failures/__tests__/assertion-count-test.js b/integration_tests/failures/__tests__/assertion_count.test.js
similarity index 100%
rename from integration_tests/failures/__tests__/assertion-count-test.js
rename to integration_tests/failures/__tests__/assertion_count.test.js
diff --git a/integration_tests/failures/__tests__/node-assertion-error-test.js b/integration_tests/failures/__tests__/node_assertion_error.test.js
similarity index 100%
rename from integration_tests/failures/__tests__/node-assertion-error-test.js
rename to integration_tests/failures/__tests__/node_assertion_error.test.js
diff --git a/integration_tests/failures/__tests__/throw-number-test.js b/integration_tests/failures/__tests__/throw_number.test.js
similarity index 100%
rename from integration_tests/failures/__tests__/throw-number-test.js
rename to integration_tests/failures/__tests__/throw_number.test.js
diff --git a/integration_tests/failures/__tests__/throw-object-test.js b/integration_tests/failures/__tests__/throw_object.test.js
similarity index 100%
rename from integration_tests/failures/__tests__/throw-object-test.js
rename to integration_tests/failures/__tests__/throw_object.test.js
diff --git a/integration_tests/failures/__tests__/throw-string-test.js b/integration_tests/failures/__tests__/throw_string.test.js
similarity index 100%
rename from integration_tests/failures/__tests__/throw-string-test.js
rename to integration_tests/failures/__tests__/throw_string.test.js
diff --git a/integration_tests/jasmine_async/__tests__/concurrent-test.js b/integration_tests/jasmine_async/__tests__/concurrent.test.js
similarity index 100%
rename from integration_tests/jasmine_async/__tests__/concurrent-test.js
rename to integration_tests/jasmine_async/__tests__/concurrent.test.js
diff --git a/integration_tests/jasmine_async/__tests__/promise_afterAll-test.js b/integration_tests/jasmine_async/__tests__/promise_after_all.test.js
similarity index 100%
rename from integration_tests/jasmine_async/__tests__/promise_afterAll-test.js
rename to integration_tests/jasmine_async/__tests__/promise_after_all.test.js
diff --git a/integration_tests/jasmine_async/__tests__/promise_afterEach-test.js b/integration_tests/jasmine_async/__tests__/promise_after_each.test.js
similarity index 100%
rename from integration_tests/jasmine_async/__tests__/promise_afterEach-test.js
rename to integration_tests/jasmine_async/__tests__/promise_after_each.test.js
diff --git a/integration_tests/jasmine_async/__tests__/promise_beforeAll-test.js b/integration_tests/jasmine_async/__tests__/promise_before_all.test.js
similarity index 100%
rename from integration_tests/jasmine_async/__tests__/promise_beforeAll-test.js
rename to integration_tests/jasmine_async/__tests__/promise_before_all.test.js
diff --git a/integration_tests/jasmine_async/__tests__/promise_beforeEach-test.js b/integration_tests/jasmine_async/__tests__/promise_before_each.test.js
similarity index 100%
rename from integration_tests/jasmine_async/__tests__/promise_beforeEach-test.js
rename to integration_tests/jasmine_async/__tests__/promise_before_each.test.js
diff --git a/integration_tests/jasmine_async/__tests__/promise_fit-test.js b/integration_tests/jasmine_async/__tests__/promise_fit.test.js
similarity index 100%
rename from integration_tests/jasmine_async/__tests__/promise_fit-test.js
rename to integration_tests/jasmine_async/__tests__/promise_fit.test.js
diff --git a/integration_tests/jasmine_async/__tests__/promise_it-test.js b/integration_tests/jasmine_async/__tests__/promise_it.test.js
similarity index 100%
rename from integration_tests/jasmine_async/__tests__/promise_it-test.js
rename to integration_tests/jasmine_async/__tests__/promise_it.test.js
diff --git a/integration_tests/jasmine_async/__tests__/promise_xit-test.js b/integration_tests/jasmine_async/__tests__/promise_xit.test.js
similarity index 100%
rename from integration_tests/jasmine_async/__tests__/promise_xit-test.js
rename to integration_tests/jasmine_async/__tests__/promise_xit.test.js
diff --git a/integration_tests/jasmine_async/__tests__/returning_values-test.js b/integration_tests/jasmine_async/__tests__/returning_values.test.js
similarity index 100%
rename from integration_tests/jasmine_async/__tests__/returning_values-test.js
rename to integration_tests/jasmine_async/__tests__/returning_values.test.js
diff --git a/integration_tests/json_reporter/__tests__/sum-test.js b/integration_tests/json_reporter/__tests__/sum.test.js
similarity index 100%
rename from integration_tests/json_reporter/__tests__/sum-test.js
rename to integration_tests/json_reporter/__tests__/sum.test.js
diff --git a/integration_tests/list_tests/__tests__/dummy-test.js b/integration_tests/list_tests/__tests__/dummy.test.js
similarity index 100%
rename from integration_tests/list_tests/__tests__/dummy-test.js
rename to integration_tests/list_tests/__tests__/dummy.test.js
diff --git a/integration_tests/native-async-mock/__tests__/native-async-mock-test.js b/integration_tests/native-async-mock/__tests__/native_async_mock.test.js
similarity index 100%
rename from integration_tests/native-async-mock/__tests__/native-async-mock-test.js
rename to integration_tests/native-async-mock/__tests__/native_async_mock.test.js
diff --git a/integration_tests/node_path/__tests__/node_path-test.js b/integration_tests/node_path/__tests__/node_path.test.js
similarity index 100%
rename from integration_tests/node_path/__tests__/node_path-test.js
rename to integration_tests/node_path/__tests__/node_path.test.js
diff --git a/integration_tests/regex-(char-in-path/__tests__/regex-(char-in-path.test.js b/integration_tests/regex-(char-in-path/__tests__/regex_(char_in_path.test.js
similarity index 100%
rename from integration_tests/regex-(char-in-path/__tests__/regex-(char-in-path.test.js
rename to integration_tests/regex-(char-in-path/__tests__/regex_(char_in_path.test.js
diff --git a/integration_tests/resolve/__tests__/resolve-test.js b/integration_tests/resolve/__tests__/resolve.test.js
similarity index 100%
rename from integration_tests/resolve/__tests__/resolve-test.js
rename to integration_tests/resolve/__tests__/resolve.test.js
diff --git a/integration_tests/runtime-internal-module-registry/__tests__/runtime-internal-module-registry-test.js b/integration_tests/runtime-internal-module-registry/__tests__/runtime_internal_module_registry.test.js
similarity index 100%
rename from integration_tests/runtime-internal-module-registry/__tests__/runtime-internal-module-registry-test.js
rename to integration_tests/runtime-internal-module-registry/__tests__/runtime_internal_module_registry.test.js
diff --git a/integration_tests/set_immediate/__tests__/set-immediate-test.js b/integration_tests/set_immediate/__tests__/set_immediate.test.js
similarity index 100%
rename from integration_tests/set_immediate/__tests__/set-immediate-test.js
rename to integration_tests/set_immediate/__tests__/set_immediate.test.js
diff --git a/integration_tests/setup_test_framework_script_file_cli_config/__tests__/runner_patch-test.js b/integration_tests/setup_test_framework_script_file_cli_config/__tests__/runner_patch.test.js
similarity index 100%
rename from integration_tests/setup_test_framework_script_file_cli_config/__tests__/runner_patch-test.js
rename to integration_tests/setup_test_framework_script_file_cli_config/__tests__/runner_patch.test.js
diff --git a/integration_tests/setup_test_framework_script_file_cli_config/__tests__/test1-test.js b/integration_tests/setup_test_framework_script_file_cli_config/__tests__/test1.test.js
similarity index 100%
rename from integration_tests/setup_test_framework_script_file_cli_config/__tests__/test1-test.js
rename to integration_tests/setup_test_framework_script_file_cli_config/__tests__/test1.test.js
diff --git a/integration_tests/setup_test_framework_script_file_cli_config/__tests__/test2-test.js b/integration_tests/setup_test_framework_script_file_cli_config/__tests__/test2.test.js
similarity index 100%
rename from integration_tests/setup_test_framework_script_file_cli_config/__tests__/test2-test.js
rename to integration_tests/setup_test_framework_script_file_cli_config/__tests__/test2.test.js
diff --git a/integration_tests/snapshot-escape/__tests__/snapshot-test.js b/integration_tests/snapshot-escape/__tests__/snapshot.test.js
similarity index 100%
rename from integration_tests/snapshot-escape/__tests__/snapshot-test.js
rename to integration_tests/snapshot-escape/__tests__/snapshot.test.js
diff --git a/integration_tests/snapshot-escape/__tests__/snapshot-escape-regex.js b/integration_tests/snapshot-escape/__tests__/snapshot_escape_regex.js
similarity index 100%
rename from integration_tests/snapshot-escape/__tests__/snapshot-escape-regex.js
rename to integration_tests/snapshot-escape/__tests__/snapshot_escape_regex.js
diff --git a/integration_tests/snapshot-escape/__tests__/snapshot-escape-substitution-test.js b/integration_tests/snapshot-escape/__tests__/snapshot_escape_substitution.test.js
similarity index 100%
rename from integration_tests/snapshot-escape/__tests__/snapshot-escape-substitution-test.js
rename to integration_tests/snapshot-escape/__tests__/snapshot_escape_substitution.test.js
diff --git a/integration_tests/snapshot-serializers/__tests__/snapshot-test.js b/integration_tests/snapshot-serializers/__tests__/snapshot.test.js
similarity index 100%
rename from integration_tests/snapshot-serializers/__tests__/snapshot-test.js
rename to integration_tests/snapshot-serializers/__tests__/snapshot.test.js
diff --git a/integration_tests/snapshot/__tests__/second-snapshot-test.js b/integration_tests/snapshot/__tests__/second_snapshot.test.js
similarity index 100%
rename from integration_tests/snapshot/__tests__/second-snapshot-test.js
rename to integration_tests/snapshot/__tests__/second_snapshot.test.js
diff --git a/integration_tests/snapshot/__tests__/snapshot-test.js b/integration_tests/snapshot/__tests__/snapshot.test.js
similarity index 100%
rename from integration_tests/snapshot/__tests__/snapshot-test.js
rename to integration_tests/snapshot/__tests__/snapshot.test.js
diff --git a/integration_tests/stack_trace/__tests__/runtime-error-test.js b/integration_tests/stack_trace/__tests__/runtime_error.test.js
similarity index 100%
rename from integration_tests/stack_trace/__tests__/runtime-error-test.js
rename to integration_tests/stack_trace/__tests__/runtime_error.test.js
diff --git a/integration_tests/stack_trace/__tests__/stack-trace-test.js b/integration_tests/stack_trace/__tests__/stack_trace.test.js
similarity index 100%
rename from integration_tests/stack_trace/__tests__/stack-trace-test.js
rename to integration_tests/stack_trace/__tests__/stack_trace.test.js
diff --git a/integration_tests/stack_trace/__tests__/stack-trace-without-message-test.js b/integration_tests/stack_trace/__tests__/stack_trace_without_message.test.js
similarity index 100%
rename from integration_tests/stack_trace/__tests__/stack-trace-without-message-test.js
rename to integration_tests/stack_trace/__tests__/stack_trace_without_message.test.js
diff --git a/integration_tests/stack_trace/__tests__/test-error-test.js b/integration_tests/stack_trace/__tests__/test_error.test.js
similarity index 100%
rename from integration_tests/stack_trace/__tests__/test-error-test.js
rename to integration_tests/stack_trace/__tests__/test_error.test.js
diff --git a/integration_tests/test-environment/__tests__/env-test.js b/integration_tests/test-environment/__tests__/env.test.js
similarity index 100%
rename from integration_tests/test-environment/__tests__/env-test.js
rename to integration_tests/test-environment/__tests__/env.test.js
diff --git a/integration_tests/testNamePattern/__tests__/testNamePattern-test.js b/integration_tests/testNamePattern/__tests__/test_name_pattern.test.js
similarity index 100%
rename from integration_tests/testNamePattern/__tests__/testNamePattern-test.js
rename to integration_tests/testNamePattern/__tests__/test_name_pattern.test.js
diff --git a/integration_tests/testResultsProcessor/__tests__/processor-test.js b/integration_tests/testResultsProcessor/__tests__/processor.test.js
similarity index 100%
rename from integration_tests/testResultsProcessor/__tests__/processor-test.js
rename to integration_tests/testResultsProcessor/__tests__/processor.test.js
diff --git a/integration_tests/timer-resetMocks/with_resetMocks/timer_with_mock.test.js b/integration_tests/timer-resetMocks/with_resetMocks/timer_with_mock.test.js
index 91cc4cc29fbf..30c0132f97b8 100644
--- a/integration_tests/timer-resetMocks/with_resetMocks/timer_with_mock.test.js
+++ b/integration_tests/timer-resetMocks/with_resetMocks/timer_with_mock.test.js
@@ -1,6 +1,7 @@
 describe('timers', () => {
   it('should work before calling resetAllMocks', () => {
     const f = jest.fn();
+    jest.useFakeTimers();
     setImmediate(() => f());
     jest.runAllImmediates();
     expect(f.mock.calls.length).toBe(1);
diff --git a/integration_tests/timer-useRealTimers/__tests__/use_real_timers.test.js b/integration_tests/timer_use_real_timers/__tests__/use_real_timers.test.js
similarity index 100%
rename from integration_tests/timer-useRealTimers/__tests__/use_real_timers.test.js
rename to integration_tests/timer_use_real_timers/__tests__/use_real_timers.test.js
diff --git a/integration_tests/timer-useRealTimers/package.json b/integration_tests/timer_use_real_timers/package.json
similarity index 100%
rename from integration_tests/timer-useRealTimers/package.json
rename to integration_tests/timer_use_real_timers/package.json
diff --git a/integration_tests/transform/babel-jest/__tests__/babel-jest-test.js b/integration_tests/transform/babel-jest/__tests__/babel_jest.test.js
similarity index 100%
rename from integration_tests/transform/babel-jest/__tests__/babel-jest-test.js
rename to integration_tests/transform/babel-jest/__tests__/babel_jest.test.js
diff --git a/integration_tests/transform/custom-instrumenting-preprocessor/__tests__/custom-preprocessor-test.js b/integration_tests/transform/custom-instrumenting-preprocessor/__tests__/custom_preprocessor.test.js
similarity index 100%
rename from integration_tests/transform/custom-instrumenting-preprocessor/__tests__/custom-preprocessor-test.js
rename to integration_tests/transform/custom-instrumenting-preprocessor/__tests__/custom_preprocessor.test.js
diff --git a/integration_tests/transform/multiple-transformers/__tests__/__snapshots__/multiple-transformers-test.js.snap b/integration_tests/transform/multiple-transformers/__tests__/__snapshots__/multiple_transformers.test.js.snap
similarity index 100%
rename from integration_tests/transform/multiple-transformers/__tests__/__snapshots__/multiple-transformers-test.js.snap
rename to integration_tests/transform/multiple-transformers/__tests__/__snapshots__/multiple_transformers.test.js.snap
diff --git a/integration_tests/transform/multiple-transformers/__tests__/multiple-transformers-test.js b/integration_tests/transform/multiple-transformers/__tests__/multiple_transformers.test.js
similarity index 100%
rename from integration_tests/transform/multiple-transformers/__tests__/multiple-transformers-test.js
rename to integration_tests/transform/multiple-transformers/__tests__/multiple_transformers.test.js
diff --git a/integration_tests/transform/no-babel-jest/__tests__/fails-with-syntax-error-test.js b/integration_tests/transform/no-babel-jest/__tests__/fails_with_syntax_error.test.js
similarity index 100%
rename from integration_tests/transform/no-babel-jest/__tests__/fails-with-syntax-error-test.js
rename to integration_tests/transform/no-babel-jest/__tests__/fails_with_syntax_error.test.js
diff --git a/integration_tests/utils.js b/integration_tests/utils.js
index 112c3e1bf68d..0dda845eca52 100644
--- a/integration_tests/utils.js
+++ b/integration_tests/utils.js
@@ -65,7 +65,7 @@ const cleanup = (directory: string) => rimraf.sync(directory);
  *   '/home/tmp',
  *   {
  *     'package.json': '{}',
- *     '__tests__/test-test.js': 'test("lol")',
+ *     '__tests__/test.test.js': 'test("lol")',
  *   }
  * );
  */
diff --git a/integration_tests/verbose_reporter/__tests__/verbose-test.js b/integration_tests/verbose_reporter/__tests__/verbose.test.js
similarity index 100%
rename from integration_tests/verbose_reporter/__tests__/verbose-test.js
rename to integration_tests/verbose_reporter/__tests__/verbose.test.js
diff --git a/package.json b/package.json
index fe8499402819..ff6a5ffd4f7d 100644
--- a/package.json
+++ b/package.json
@@ -100,7 +100,7 @@
     },
     "setupTestFrameworkScriptFile": "<rootDir>/testSetupFile.js",
     "snapshotSerializers": [
-      "<rootDir>/packages/pretty-format/build/plugins/ConvertAnsi.js"
+      "<rootDir>/packages/pretty-format/build/plugins/convert_ansi.js"
     ],
     "testEnvironment": "./packages/jest-environment-node",
     "testPathIgnorePatterns": [
@@ -112,7 +112,7 @@
       "/packages/.*/build-es5"
     ],
     "testMatch": [
-      "**/*-test.js"
+      "**/*.test.js"
     ]
   }
 }
diff --git a/packages/eslint-plugin-jest/src/index.js b/packages/eslint-plugin-jest/src/index.js
index e3899b0c70ba..32791fe38b02 100644
--- a/packages/eslint-plugin-jest/src/index.js
+++ b/packages/eslint-plugin-jest/src/index.js
@@ -8,10 +8,10 @@
  * @flow
  */
 
-import noDisabledTests from './rules/no-disabled-tests';
-import noFocusedTests from './rules/no-focused-tests';
-import noIdenticalTitle from './rules/no-identical-title';
-import validExpect from './rules/valid-expect';
+import noDisabledTests from './rules/no_disabled_tests';
+import noFocusedTests from './rules/no_focused_tests';
+import noIdenticalTitle from './rules/no_identical_title';
+import validExpect from './rules/valid_expect';
 
 module.exports = {
   configs: {
diff --git a/packages/eslint-plugin-jest/src/rules/__tests__/no-focused-tests-test.js b/packages/eslint-plugin-jest/src/rules/__tests__/no_focused_tests.test.js
similarity index 100%
rename from packages/eslint-plugin-jest/src/rules/__tests__/no-focused-tests-test.js
rename to packages/eslint-plugin-jest/src/rules/__tests__/no_focused_tests.test.js
diff --git a/packages/eslint-plugin-jest/src/rules/__tests__/no-identical-title-test.js b/packages/eslint-plugin-jest/src/rules/__tests__/no_identical_title.test.js
similarity index 100%
rename from packages/eslint-plugin-jest/src/rules/__tests__/no-identical-title-test.js
rename to packages/eslint-plugin-jest/src/rules/__tests__/no_identical_title.test.js
diff --git a/packages/eslint-plugin-jest/src/rules/__tests__/no-skipped-tests-test.js b/packages/eslint-plugin-jest/src/rules/__tests__/no_skipped_tests.test.js
similarity index 100%
rename from packages/eslint-plugin-jest/src/rules/__tests__/no-skipped-tests-test.js
rename to packages/eslint-plugin-jest/src/rules/__tests__/no_skipped_tests.test.js
diff --git a/packages/eslint-plugin-jest/src/rules/__tests__/valid-expect-test.js b/packages/eslint-plugin-jest/src/rules/__tests__/valid_expect.test.js
similarity index 100%
rename from packages/eslint-plugin-jest/src/rules/__tests__/valid-expect-test.js
rename to packages/eslint-plugin-jest/src/rules/__tests__/valid_expect.test.js
diff --git a/packages/eslint-plugin-jest/src/rules/no-disabled-tests.js b/packages/eslint-plugin-jest/src/rules/no_disabled_tests.js
similarity index 100%
rename from packages/eslint-plugin-jest/src/rules/no-disabled-tests.js
rename to packages/eslint-plugin-jest/src/rules/no_disabled_tests.js
diff --git a/packages/eslint-plugin-jest/src/rules/no-focused-tests.js b/packages/eslint-plugin-jest/src/rules/no_focused_tests.js
similarity index 100%
rename from packages/eslint-plugin-jest/src/rules/no-focused-tests.js
rename to packages/eslint-plugin-jest/src/rules/no_focused_tests.js
diff --git a/packages/eslint-plugin-jest/src/rules/no-identical-title.js b/packages/eslint-plugin-jest/src/rules/no_identical_title.js
similarity index 100%
rename from packages/eslint-plugin-jest/src/rules/no-identical-title.js
rename to packages/eslint-plugin-jest/src/rules/no_identical_title.js
diff --git a/packages/eslint-plugin-jest/src/rules/valid-expect.js b/packages/eslint-plugin-jest/src/rules/valid_expect.js
similarity index 100%
rename from packages/eslint-plugin-jest/src/rules/valid-expect.js
rename to packages/eslint-plugin-jest/src/rules/valid_expect.js
diff --git a/packages/jest-changed-files/src/__tests__/git-test.js b/packages/jest-changed-files/src/__tests__/git.test.js
similarity index 100%
rename from packages/jest-changed-files/src/__tests__/git-test.js
rename to packages/jest-changed-files/src/__tests__/git.test.js
diff --git a/packages/jest-changed-files/src/__tests__/hg-test.js b/packages/jest-changed-files/src/__tests__/hg.test.js
similarity index 100%
rename from packages/jest-changed-files/src/__tests__/hg-test.js
rename to packages/jest-changed-files/src/__tests__/hg.test.js
diff --git a/packages/jest-circus/src/eventHandler.js b/packages/jest-circus/src/event_handler.js
similarity index 100%
rename from packages/jest-circus/src/eventHandler.js
rename to packages/jest-circus/src/event_handler.js
diff --git a/packages/jest-circus/src/formatNodeAssertErrors.js b/packages/jest-circus/src/format_node_assert_errors.js
similarity index 98%
rename from packages/jest-circus/src/formatNodeAssertErrors.js
rename to packages/jest-circus/src/format_node_assert_errors.js
index ed4d022afb02..be326feafd4d 100644
--- a/packages/jest-circus/src/formatNodeAssertErrors.js
+++ b/packages/jest-circus/src/format_node_assert_errors.js
@@ -8,7 +8,7 @@
  * @flow
  */
 
-import type {DiffOptions} from 'jest-diff/src/diffStrings';
+import type {DiffOptions} from 'jest-diff/src/diff_strings.js';
 import type {Event, State} from '../types';
 
 const {printReceived, printExpected} = require('jest-matcher-utils');
diff --git a/packages/jest-circus/src/legacy_code_todo_rewrite/jest-adapter.js b/packages/jest-circus/src/legacy_code_todo_rewrite/jest_adapter.js
similarity index 97%
rename from packages/jest-circus/src/legacy_code_todo_rewrite/jest-adapter.js
rename to packages/jest-circus/src/legacy_code_todo_rewrite/jest_adapter.js
index 6047ff2b6ce4..47ce069bfa99 100644
--- a/packages/jest-circus/src/legacy_code_todo_rewrite/jest-adapter.js
+++ b/packages/jest-circus/src/legacy_code_todo_rewrite/jest_adapter.js
@@ -28,7 +28,7 @@ const jestAdapter = async (
     runAndTransformResultsToJestFormat,
   } = runtime.requireInternalModule(FRAMEWORK_INITIALIZER);
 
-  runtime.requireInternalModule(path.resolve(__dirname, './jest-expect.js'))({
+  runtime.requireInternalModule(path.resolve(__dirname, './jest_expect.js'))({
     expand: globalConfig.expand,
   });
 
diff --git a/packages/jest-circus/src/legacy_code_todo_rewrite/jest-adapter-init.js b/packages/jest-circus/src/legacy_code_todo_rewrite/jest_adapter_init.js
similarity index 100%
rename from packages/jest-circus/src/legacy_code_todo_rewrite/jest-adapter-init.js
rename to packages/jest-circus/src/legacy_code_todo_rewrite/jest_adapter_init.js
diff --git a/packages/jest-circus/src/legacy_code_todo_rewrite/jest-expect.js b/packages/jest-circus/src/legacy_code_todo_rewrite/jest_expect.js
similarity index 100%
rename from packages/jest-circus/src/legacy_code_todo_rewrite/jest-expect.js
rename to packages/jest-circus/src/legacy_code_todo_rewrite/jest_expect.js
diff --git a/packages/jest-circus/src/state.js b/packages/jest-circus/src/state.js
index 20b0dbe272fa..1d58be08aa67 100644
--- a/packages/jest-circus/src/state.js
+++ b/packages/jest-circus/src/state.js
@@ -11,8 +11,8 @@
 import type {Event, State, EventHandler} from '../types';
 
 import {makeDescribe} from './utils';
-import eventHandler from './eventHandler';
-import formatNodeAssertErrors from './formatNodeAssertErrors';
+import eventHandler from './event_handler';
+import formatNodeAssertErrors from './format_node_assert_errors';
 
 const eventHandlers: Array<EventHandler> = [
   eventHandler,
diff --git a/packages/jest-cli/src/__tests__/__snapshots__/generateEmptyCoverage-test.js.snap b/packages/jest-cli/src/__tests__/__snapshots__/generate_empty_coverage.test.js.snap
similarity index 100%
rename from packages/jest-cli/src/__tests__/__snapshots__/generateEmptyCoverage-test.js.snap
rename to packages/jest-cli/src/__tests__/__snapshots__/generate_empty_coverage.test.js.snap
diff --git a/packages/jest-cli/src/__tests__/__snapshots__/watch-test.js.snap b/packages/jest-cli/src/__tests__/__snapshots__/watch.test.js.snap
similarity index 100%
rename from packages/jest-cli/src/__tests__/__snapshots__/watch-test.js.snap
rename to packages/jest-cli/src/__tests__/__snapshots__/watch.test.js.snap
diff --git a/packages/jest-cli/src/__tests__/__snapshots__/watch-filename-pattern-mode-test.js.snap b/packages/jest-cli/src/__tests__/__snapshots__/watch_filename_pattern_mode.test.js.snap
similarity index 100%
rename from packages/jest-cli/src/__tests__/__snapshots__/watch-filename-pattern-mode-test.js.snap
rename to packages/jest-cli/src/__tests__/__snapshots__/watch_filename_pattern_mode.test.js.snap
diff --git a/packages/jest-cli/src/__tests__/__snapshots__/watch-test-name-pattern-mode-test.js.snap b/packages/jest-cli/src/__tests__/__snapshots__/watch_test_name_pattern_mode.test.js.snap
similarity index 100%
rename from packages/jest-cli/src/__tests__/__snapshots__/watch-test-name-pattern-mode-test.js.snap
rename to packages/jest-cli/src/__tests__/__snapshots__/watch_test_name_pattern_mode.test.js.snap
diff --git a/packages/jest-cli/src/__tests__/generateEmptyCoverage-test.js b/packages/jest-cli/src/__tests__/generate_empty_coverage.test.js
similarity index 100%
rename from packages/jest-cli/src/__tests__/generateEmptyCoverage-test.js
rename to packages/jest-cli/src/__tests__/generate_empty_coverage.test.js
diff --git a/packages/jest-cli/src/__tests__/globals-test.js b/packages/jest-cli/src/__tests__/globals.test.js
similarity index 100%
rename from packages/jest-cli/src/__tests__/globals-test.js
rename to packages/jest-cli/src/__tests__/globals.test.js
diff --git a/packages/jest-cli/src/__tests__/SearchSource-test.js b/packages/jest-cli/src/__tests__/search_source.test.js
similarity index 100%
rename from packages/jest-cli/src/__tests__/SearchSource-test.js
rename to packages/jest-cli/src/__tests__/search_source.test.js
diff --git a/packages/jest-cli/src/__tests__/TestRunner-test.js b/packages/jest-cli/src/__tests__/test_runner.test.js
similarity index 78%
rename from packages/jest-cli/src/__tests__/TestRunner-test.js
rename to packages/jest-cli/src/__tests__/test_runner.test.js
index 795c97b36b26..1a86a2cceb33 100644
--- a/packages/jest-cli/src/__tests__/TestRunner-test.js
+++ b/packages/jest-cli/src/__tests__/test_runner.test.js
@@ -44,12 +44,15 @@ describe('_createInBandTestRun()', () => {
     const globalConfig = {watch: true};
     const config = {rootDir: '/path/'};
     const rawModuleMap = jest.fn();
-    const context = {config, moduleMap: {getRawModuleMap: () => rawModuleMap}};
+    const context = {
+      config,
+      moduleMap: {getRawModuleMap: () => rawModuleMap},
+    };
     const runner = new TestRunner(globalConfig, {maxWorkers: 2});
 
     return runner
       ._createParallelTestRun(
-        [{context, path: './file-test.js'}, {context, path: './file2-test.js'}],
+        [{context, path: './file.test.js'}, {context, path: './file2.test.js'}],
         new TestWatcher({isWatchMode: globalConfig.watch}),
         () => {},
         () => {},
@@ -57,11 +60,11 @@ describe('_createInBandTestRun()', () => {
       .then(() => {
         expect(workerFarmMock.mock.calls).toEqual([
           [
-            {config, globalConfig, path: './file-test.js', rawModuleMap},
+            {config, globalConfig, path: './file.test.js', rawModuleMap},
             expect.any(Function),
           ],
           [
-            {config, globalConfig, path: './file2-test.js', rawModuleMap},
+            {config, globalConfig, path: './file2.test.js', rawModuleMap},
             expect.any(Function),
           ],
         ]);
@@ -76,7 +79,7 @@ describe('_createInBandTestRun()', () => {
 
     return runner
       ._createParallelTestRun(
-        [{context, path: './file-test.js'}, {context, path: './file2-test.js'}],
+        [{context, path: './file.test.js'}, {context, path: './file2.test.js'}],
         new TestWatcher({isWatchMode: globalConfig.watch}),
         () => {},
         () => {},
@@ -84,11 +87,21 @@ describe('_createInBandTestRun()', () => {
       .then(() => {
         expect(workerFarmMock.mock.calls).toEqual([
           [
-            {config, globalConfig, path: './file-test.js', rawModuleMap: null},
+            {
+              config,
+              globalConfig,
+              path: './file.test.js',
+              rawModuleMap: null,
+            },
             expect.any(Function),
           ],
           [
-            {config, globalConfig, path: './file2-test.js', rawModuleMap: null},
+            {
+              config,
+              globalConfig,
+              path: './file2.test.js',
+              rawModuleMap: null,
+            },
             expect.any(Function),
           ],
         ]);
diff --git a/packages/jest-cli/src/__tests__/TestSequencer-test.js b/packages/jest-cli/src/__tests__/test_sequencer.test.js
similarity index 100%
rename from packages/jest-cli/src/__tests__/TestSequencer-test.js
rename to packages/jest-cli/src/__tests__/test_sequencer.test.js
diff --git a/packages/jest-cli/src/__tests__/watch-test.js b/packages/jest-cli/src/__tests__/watch.test.js
similarity index 100%
rename from packages/jest-cli/src/__tests__/watch-test.js
rename to packages/jest-cli/src/__tests__/watch.test.js
diff --git a/packages/jest-cli/src/__tests__/watch-filename-pattern-mode-test.js b/packages/jest-cli/src/__tests__/watch_filename_pattern_mode.test.js
similarity index 100%
rename from packages/jest-cli/src/__tests__/watch-filename-pattern-mode-test.js
rename to packages/jest-cli/src/__tests__/watch_filename_pattern_mode.test.js
diff --git a/packages/jest-cli/src/__tests__/watch-test-name-pattern-mode-test.js b/packages/jest-cli/src/__tests__/watch_test_name_pattern_mode.test.js
similarity index 100%
rename from packages/jest-cli/src/__tests__/watch-test-name-pattern-mode-test.js
rename to packages/jest-cli/src/__tests__/watch_test_name_pattern_mode.test.js
diff --git a/packages/jest-cli/src/lib/__tests__/__snapshots__/formatTestNameByPattern-test.js.snap b/packages/jest-cli/src/lib/__tests__/__snapshots__/format_test_name_by_pattern.test.js.snap
similarity index 100%
rename from packages/jest-cli/src/lib/__tests__/__snapshots__/formatTestNameByPattern-test.js.snap
rename to packages/jest-cli/src/lib/__tests__/__snapshots__/format_test_name_by_pattern.test.js.snap
diff --git a/packages/jest-cli/src/lib/__tests__/__snapshots__/highlight-test.js.snap b/packages/jest-cli/src/lib/__tests__/__snapshots__/highlight.test.js.snap
similarity index 68%
rename from packages/jest-cli/src/lib/__tests__/__snapshots__/highlight-test.js.snap
rename to packages/jest-cli/src/lib/__tests__/__snapshots__/highlight.test.js.snap
index 803e3b8c5dd6..f9e7d455a94a 100644
--- a/packages/jest-cli/src/lib/__tests__/__snapshots__/highlight-test.js.snap
+++ b/packages/jest-cli/src/lib/__tests__/__snapshots__/highlight.test.js.snap
@@ -1,77 +1,77 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`dims everything when there is no match 1`] = `"<dim>jest-cli/__tests__/watch-test.js"`;
+exports[`dims everything when there is no match 1`] = `"<dim>jest-cli/__tests__/watch.test.js"`;
 
-exports[`dims everything when there is no match 2`] = `"<dim>...t-cli/__tests__/watch-test.js"`;
+exports[`dims everything when there is no match 2`] = `"<dim>...t-cli/__tests__/watch.test.js"`;
 
-exports[`dims everything when there is no match 3`] = `"<dim>.../__tests__/watch-test.js"`;
+exports[`dims everything when there is no match 3`] = `"<dim>.../__tests__/watch.test.js"`;
 
-exports[`dims everything when there is no match 4`] = `"<dim>...sts__/watch-test.js"`;
+exports[`dims everything when there is no match 4`] = `"<dim>...sts__/watch.test.js"`;
 
-exports[`dims everything when there is no match 5`] = `"<dim>...watch-test.js"`;
+exports[`dims everything when there is no match 5`] = `"<dim>...watch.test.js"`;
 
-exports[`dims everything when there is no match 6`] = `"<dim>...-test.js"`;
+exports[`dims everything when there is no match 6`] = `"<dim>....test.js"`;
 
 exports[`dims everything when there is no match 7`] = `"<dim>....js"`;
 
-exports[`dims everything when there is no match 8`] = `"<dim>./watch-test.js"`;
+exports[`dims everything when there is no match 8`] = `"<dim>./watch.test.js"`;
 
-exports[`highlight the trimmed part when there is only a rootDir match 1`] = `"<dim>jest-cli/__tests__/watch-test.js"`;
+exports[`highlight the trimmed part when there is only a rootDir match 1`] = `"<dim>jest-cli/__tests__/watch.test.js"`;
 
-exports[`highlight the trimmed part when there is only a rootDir match 2`] = `"</>...</><dim>t-cli/__tests__/watch-test.js"`;
+exports[`highlight the trimmed part when there is only a rootDir match 2`] = `"</>...</><dim>t-cli/__tests__/watch.test.js"`;
 
-exports[`highlight the trimmed part when there is only a rootDir match 3`] = `"</>...</><dim>/__tests__/watch-test.js"`;
+exports[`highlight the trimmed part when there is only a rootDir match 3`] = `"</>...</><dim>/__tests__/watch.test.js"`;
 
-exports[`highlight the trimmed part when there is only a rootDir match 4`] = `"</>...</><dim>sts__/watch-test.js"`;
+exports[`highlight the trimmed part when there is only a rootDir match 4`] = `"</>...</><dim>sts__/watch.test.js"`;
 
-exports[`highlight the trimmed part when there is only a rootDir match 5`] = `"</>...</><dim>watch-test.js"`;
+exports[`highlight the trimmed part when there is only a rootDir match 5`] = `"</>...</><dim>watch.test.js"`;
 
-exports[`highlight the trimmed part when there is only a rootDir match 6`] = `"</>...</><dim>-test.js"`;
+exports[`highlight the trimmed part when there is only a rootDir match 6`] = `"</>...</><dim>.test.js"`;
 
 exports[`highlight the trimmed part when there is only a rootDir match 7`] = `"</>...</><dim>.js"`;
 
-exports[`highlight the trimmed part when there is only a rootDir match 8`] = `"</>./</><dim>watch-test.js"`;
+exports[`highlight the trimmed part when there is only a rootDir match 8`] = `"</>./</><dim>watch.test.js"`;
 
-exports[`highlights everything when there is a full match 1`] = `"</>jest-cli/__tests__/watch-test.js</>"`;
+exports[`highlights everything when there is a full match 1`] = `"</>jest-cli/__tests__/watch.test.js</>"`;
 
-exports[`highlights everything when there is a full match 2`] = `"</>...t-cli/__tests__/watch-test.js</>"`;
+exports[`highlights everything when there is a full match 2`] = `"</>...t-cli/__tests__/watch.test.js</>"`;
 
-exports[`highlights everything when there is a full match 3`] = `"</>.../__tests__/watch-test.js</>"`;
+exports[`highlights everything when there is a full match 3`] = `"</>.../__tests__/watch.test.js</>"`;
 
-exports[`highlights everything when there is a full match 4`] = `"</>...sts__/watch-test.js</>"`;
+exports[`highlights everything when there is a full match 4`] = `"</>...sts__/watch.test.js</>"`;
 
-exports[`highlights everything when there is a full match 5`] = `"</>...watch-test.js</>"`;
+exports[`highlights everything when there is a full match 5`] = `"</>...watch.test.js</>"`;
 
-exports[`highlights everything when there is a full match 6`] = `"</>...-test.js</>"`;
+exports[`highlights everything when there is a full match 6`] = `"</>....test.js</>"`;
 
 exports[`highlights everything when there is a full match 7`] = `"</>....js</>"`;
 
-exports[`highlights everything when there is a full match 8`] = `"</>./watch-test.js</>"`;
+exports[`highlights everything when there is a full match 8`] = `"</>./watch.test.js</>"`;
 
-exports[`highlights part of file name when there is a partially match of the file name 1`] = `"<dim>jest-cli/__tests__/</>watch</><dim>-test.js"`;
+exports[`highlights part of file name when there is a partially match of the file name 1`] = `"<dim>jest-cli/__tests__/</>watch</><dim>.test.js"`;
 
-exports[`highlights part of file name when there is a partially match of the file name 2`] = `"<dim>...t-cli/__tests__/</>watch</><dim>-test.js"`;
+exports[`highlights part of file name when there is a partially match of the file name 2`] = `"<dim>...t-cli/__tests__/</>watch</><dim>.test.js"`;
 
-exports[`highlights part of file name when there is a partially match of the file name 3`] = `"<dim>.../__tests__/</>watch</><dim>-test.js"`;
+exports[`highlights part of file name when there is a partially match of the file name 3`] = `"<dim>.../__tests__/</>watch</><dim>.test.js"`;
 
-exports[`highlights part of file name when there is a partially match of the file name 4`] = `"<dim>...sts__/</>watch</><dim>-test.js"`;
+exports[`highlights part of file name when there is a partially match of the file name 4`] = `"<dim>...sts__/</>watch</><dim>.test.js"`;
 
-exports[`highlights part of file name when there is a partially match of the file name 5`] = `"<dim>...</>watch</><dim>-test.js"`;
+exports[`highlights part of file name when there is a partially match of the file name 5`] = `"<dim>...</>watch</><dim>.test.js"`;
 
-exports[`highlights part of file name when there is a partially match of the file name 6`] = `"</>...</><dim>-test.js"`;
+exports[`highlights part of file name when there is a partially match of the file name 6`] = `"</>...</><dim>.test.js"`;
 
 exports[`highlights part of file name when there is a partially match of the file name 7`] = `"</>...</><dim>.js"`;
 
-exports[`highlights part of file name when there is a partially match of the file name 8`] = `"<dim>./</>watch</><dim>-test.js"`;
+exports[`highlights part of file name when there is a partially match of the file name 8`] = `"<dim>./</>watch</><dim>.test.js"`;
 
-exports[`highlights the trimmed part there is a non visible match 1`] = `"</>...t-cli</><dim>/__tests__/watch-test.js"`;
+exports[`highlights the trimmed part there is a non visible match 1`] = `"</>...t-cli</><dim>/__tests__/watch.test.js"`;
 
-exports[`highlights the trimmed part there is a non visible match 2`] = `"</>...</><dim>/__tests__/watch-test.js"`;
+exports[`highlights the trimmed part there is a non visible match 2`] = `"</>...</><dim>/__tests__/watch.test.js"`;
 
-exports[`highlights the trimmed part there is a non visible match 3`] = `"</>...</><dim>sts__/watch-test.js"`;
+exports[`highlights the trimmed part there is a non visible match 3`] = `"</>...</><dim>sts__/watch.test.js"`;
 
-exports[`highlights the trimmed part there is a non visible match 4`] = `"</>...</><dim>watch-test.js"`;
+exports[`highlights the trimmed part there is a non visible match 4`] = `"</>...</><dim>watch.test.js"`;
 
-exports[`highlights the trimmed part there is a non visible match 5`] = `"</>...</><dim>-test.js"`;
+exports[`highlights the trimmed part there is a non visible match 5`] = `"</>...</><dim>.test.js"`;
 
 exports[`highlights the trimmed part there is a non visible match 6`] = `"</>...</><dim>.js"`;
diff --git a/packages/jest-cli/src/lib/__tests__/formatTestNameByPattern-test.js b/packages/jest-cli/src/lib/__tests__/format_test_name_by_pattern.test.js
similarity index 100%
rename from packages/jest-cli/src/lib/__tests__/formatTestNameByPattern-test.js
rename to packages/jest-cli/src/lib/__tests__/format_test_name_by_pattern.test.js
diff --git a/packages/jest-cli/src/lib/__tests__/getMaxWorkers-test.js b/packages/jest-cli/src/lib/__tests__/get_max_workers.test.js
similarity index 100%
rename from packages/jest-cli/src/lib/__tests__/getMaxWorkers-test.js
rename to packages/jest-cli/src/lib/__tests__/get_max_workers.test.js
diff --git a/packages/jest-cli/src/lib/__tests__/highlight-test.js b/packages/jest-cli/src/lib/__tests__/highlight.test.js
similarity index 86%
rename from packages/jest-cli/src/lib/__tests__/highlight-test.js
rename to packages/jest-cli/src/lib/__tests__/highlight.test.js
index 5544977dbba8..f94d8c08de90 100644
--- a/packages/jest-cli/src/lib/__tests__/highlight-test.js
+++ b/packages/jest-cli/src/lib/__tests__/highlight.test.js
@@ -13,16 +13,16 @@
 const highlight = require('../highlight');
 
 const rootDir = '/Users/foo/dev/jest';
-const rawPath = rootDir + '/jest-cli/__tests__/watch-test.js';
+const rawPath = rootDir + '/jest-cli/__tests__/watch.test.js';
 const relativePaths = [
-  'jest-cli/__tests__/watch-test.js',
-  '...t-cli/__tests__/watch-test.js',
-  '.../__tests__/watch-test.js',
-  '...sts__/watch-test.js',
-  '...watch-test.js',
-  '...-test.js',
+  'jest-cli/__tests__/watch.test.js',
+  '...t-cli/__tests__/watch.test.js',
+  '.../__tests__/watch.test.js',
+  '...sts__/watch.test.js',
+  '...watch.test.js',
+  '....test.js',
   '....js',
-  './watch-test.js',
+  './watch.test.js',
 ];
 
 it('highlight the trimmed part when there is only a rootDir match', () => {
diff --git a/packages/jest-cli/src/lib/__tests__/isValidPath-test.js b/packages/jest-cli/src/lib/__tests__/is_valid_path.test.js
similarity index 100%
rename from packages/jest-cli/src/lib/__tests__/isValidPath-test.js
rename to packages/jest-cli/src/lib/__tests__/is_valid_path.test.js
diff --git a/packages/jest-cli/src/lib/__tests__/logDebugMessages-test.js b/packages/jest-cli/src/lib/__tests__/log_debug_messages.test.js
similarity index 100%
rename from packages/jest-cli/src/lib/__tests__/logDebugMessages-test.js
rename to packages/jest-cli/src/lib/__tests__/log_debug_messages.test.js
diff --git a/packages/jest-cli/src/lib/__tests__/Prompt-test.js b/packages/jest-cli/src/lib/__tests__/prompt.test.js
similarity index 100%
rename from packages/jest-cli/src/lib/__tests__/Prompt-test.js
rename to packages/jest-cli/src/lib/__tests__/prompt.test.js
diff --git a/packages/jest-cli/src/lib/__tests__/scrollList-test.js b/packages/jest-cli/src/lib/__tests__/scroll_list.test.js
similarity index 100%
rename from packages/jest-cli/src/lib/__tests__/scrollList-test.js
rename to packages/jest-cli/src/lib/__tests__/scroll_list.test.js
diff --git a/packages/jest-cli/src/lib/__tests__/validatePattern-test.js b/packages/jest-cli/src/lib/__tests__/validate_pattern.test.js
similarity index 100%
rename from packages/jest-cli/src/lib/__tests__/validatePattern-test.js
rename to packages/jest-cli/src/lib/__tests__/validate_pattern.test.js
diff --git a/packages/jest-cli/src/reporters/__tests__/__snapshots__/utils-test.js.snap b/packages/jest-cli/src/reporters/__tests__/__snapshots__/utils.test.js.snap
similarity index 100%
rename from packages/jest-cli/src/reporters/__tests__/__snapshots__/utils-test.js.snap
rename to packages/jest-cli/src/reporters/__tests__/__snapshots__/utils.test.js.snap
diff --git a/packages/jest-cli/src/reporters/__tests__/CoverageReporter-test.js b/packages/jest-cli/src/reporters/__tests__/coverage_reporter.test.js
similarity index 100%
rename from packages/jest-cli/src/reporters/__tests__/CoverageReporter-test.js
rename to packages/jest-cli/src/reporters/__tests__/coverage_reporter.test.js
diff --git a/packages/jest-cli/src/reporters/__tests__/CoverageWorker-test.js b/packages/jest-cli/src/reporters/__tests__/coverage_worker.test.js
similarity index 100%
rename from packages/jest-cli/src/reporters/__tests__/CoverageWorker-test.js
rename to packages/jest-cli/src/reporters/__tests__/coverage_worker.test.js
diff --git a/packages/jest-cli/src/reporters/__tests__/utils-test.js b/packages/jest-cli/src/reporters/__tests__/utils.test.js
similarity index 100%
rename from packages/jest-cli/src/reporters/__tests__/utils-test.js
rename to packages/jest-cli/src/reporters/__tests__/utils.test.js
diff --git a/packages/jest-cli/src/reporters/__tests__/VerboseReporter-test.js b/packages/jest-cli/src/reporters/__tests__/verbose_reporter.test.js
similarity index 100%
rename from packages/jest-cli/src/reporters/__tests__/VerboseReporter-test.js
rename to packages/jest-cli/src/reporters/__tests__/verbose_reporter.test.js
diff --git a/packages/jest-config/src/__tests__/__snapshots__/normalize-test.js.snap b/packages/jest-config/src/__tests__/__snapshots__/normalize.test.js.snap
similarity index 100%
rename from packages/jest-config/src/__tests__/__snapshots__/normalize-test.js.snap
rename to packages/jest-config/src/__tests__/__snapshots__/normalize.test.js.snap
diff --git a/packages/jest-config/src/__tests__/normalize-test.js b/packages/jest-config/src/__tests__/normalize.test.js
similarity index 100%
rename from packages/jest-config/src/__tests__/normalize-test.js
rename to packages/jest-config/src/__tests__/normalize.test.js
diff --git a/packages/jest-config/src/__tests__/setFromArgv-test.js b/packages/jest-config/src/__tests__/set_from_argv.test.js
similarity index 97%
rename from packages/jest-config/src/__tests__/setFromArgv-test.js
rename to packages/jest-config/src/__tests__/set_from_argv.test.js
index 7f118d5f41e7..13fef653a613 100644
--- a/packages/jest-config/src/__tests__/setFromArgv-test.js
+++ b/packages/jest-config/src/__tests__/set_from_argv.test.js
@@ -8,7 +8,7 @@
  */
 'use strict';
 
-const setFromArgv = require('../setFromArgv');
+const setFromArgv = require('../set_from_argv');
 
 test('maps special values to valid options', () => {
   const options = {};
diff --git a/packages/jest-config/src/findConfig.js b/packages/jest-config/src/find_config.js
similarity index 100%
rename from packages/jest-config/src/findConfig.js
rename to packages/jest-config/src/find_config.js
diff --git a/packages/jest-config/src/index.js b/packages/jest-config/src/index.js
index 21bfc5e2afd1..d9c4f1859113 100644
--- a/packages/jest-config/src/index.js
+++ b/packages/jest-config/src/index.js
@@ -13,7 +13,7 @@ import type {GlobalConfig, ProjectConfig} from 'types/Config';
 
 import path from 'path';
 import {getTestEnvironment, isJSONString} from './utils';
-import findConfig from './findConfig';
+import findConfig from './find_config';
 import normalize from './normalize';
 
 function readConfig(
diff --git a/packages/jest-config/src/normalize.js b/packages/jest-config/src/normalize.js
index e9b596f951ba..2608c62f3fd5 100644
--- a/packages/jest-config/src/normalize.js
+++ b/packages/jest-config/src/normalize.js
@@ -31,11 +31,11 @@ import {
   DEFAULT_JS_PATTERN,
   DEFAULT_REPORTER_LABEL,
 } from './constants';
-import {validateReporters} from './reporterValidationErrors';
+import {validateReporters} from './reporter_validation_errors';
 import DEFAULT_CONFIG from './defaults';
 import DEPRECATED_CONFIG from './deprecated';
-import setFromArgv from './setFromArgv';
-import VALID_CONFIG from './validConfig';
+import setFromArgv from './set_from_argv';
+import VALID_CONFIG from './valid_config';
 const ERROR = `${BULLET}Validation Error`;
 const JSON_EXTENSION = '.json';
 const PRESET_NAME = 'jest-preset' + JSON_EXTENSION;
diff --git a/packages/jest-config/src/reporterValidationErrors.js b/packages/jest-config/src/reporter_validation_errors.js
similarity index 100%
rename from packages/jest-config/src/reporterValidationErrors.js
rename to packages/jest-config/src/reporter_validation_errors.js
diff --git a/packages/jest-config/src/setFromArgv.js b/packages/jest-config/src/set_from_argv.js
similarity index 100%
rename from packages/jest-config/src/setFromArgv.js
rename to packages/jest-config/src/set_from_argv.js
diff --git a/packages/jest-config/src/validConfig.js b/packages/jest-config/src/valid_config.js
similarity index 100%
rename from packages/jest-config/src/validConfig.js
rename to packages/jest-config/src/valid_config.js
diff --git a/packages/jest-diff/src/__tests__/__snapshots__/diff-test.js.snap b/packages/jest-diff/src/__tests__/__snapshots__/diff.test.js.snap
similarity index 100%
rename from packages/jest-diff/src/__tests__/__snapshots__/diff-test.js.snap
rename to packages/jest-diff/src/__tests__/__snapshots__/diff.test.js.snap
diff --git a/packages/jest-diff/src/__tests__/diff-test.js b/packages/jest-diff/src/__tests__/diff.test.js
similarity index 100%
rename from packages/jest-diff/src/__tests__/diff-test.js
rename to packages/jest-diff/src/__tests__/diff.test.js
diff --git a/packages/jest-diff/src/diffStrings.js b/packages/jest-diff/src/diff_strings.js
similarity index 100%
rename from packages/jest-diff/src/diffStrings.js
rename to packages/jest-diff/src/diff_strings.js
diff --git a/packages/jest-diff/src/index.js b/packages/jest-diff/src/index.js
index 0d56f9374cdd..be6b39a0d7b7 100644
--- a/packages/jest-diff/src/index.js
+++ b/packages/jest-diff/src/index.js
@@ -8,12 +8,12 @@
  * @flow
  */
 
-import type {DiffOptions} from './diffStrings';
+import type {DiffOptions} from './diff_strings';
 
 import prettyFormat from 'pretty-format';
 import chalk from 'chalk';
 import getType from 'jest-get-type';
-import diffStrings from './diffStrings';
+import diffStrings from './diff_strings';
 import {NO_DIFF_MESSAGE, SIMILAR_MESSAGE} from './constants';
 
 const {
diff --git a/packages/jest-docblock/src/__tests__/index-test.js b/packages/jest-docblock/src/__tests__/index.test.js
similarity index 100%
rename from packages/jest-docblock/src/__tests__/index-test.js
rename to packages/jest-docblock/src/__tests__/index.test.js
diff --git a/packages/jest-editor-support/src/__tests__/parsers/BabylonParser-test.js b/packages/jest-editor-support/src/__tests__/parsers/babylon_parser.test.js
similarity index 87%
rename from packages/jest-editor-support/src/__tests__/parsers/BabylonParser-test.js
rename to packages/jest-editor-support/src/__tests__/parsers/babylon_parser.test.js
index e5ab15171839..73d6c7b325e0 100644
--- a/packages/jest-editor-support/src/__tests__/parsers/BabylonParser-test.js
+++ b/packages/jest-editor-support/src/__tests__/parsers/babylon_parser.test.js
@@ -8,7 +8,7 @@
 
 'use strict';
 
-const {parse} = require('../../parsers/BabylonParser');
+const {parse} = require('../../parsers/babylon_parser');
 const {parserTests} = require('../../../../../fixtures/parserTests');
 
 parserTests(parse);
diff --git a/packages/jest-editor-support/src/__tests__/ProjectWorkspace-test.js b/packages/jest-editor-support/src/__tests__/project_workspace.test.js
similarity index 91%
rename from packages/jest-editor-support/src/__tests__/ProjectWorkspace-test.js
rename to packages/jest-editor-support/src/__tests__/project_workspace.test.js
index bc98bebfc496..9aa0d3cd3dba 100644
--- a/packages/jest-editor-support/src/__tests__/ProjectWorkspace-test.js
+++ b/packages/jest-editor-support/src/__tests__/project_workspace.test.js
@@ -8,7 +8,7 @@
 
 'use strict';
 
-const ProjectWorkspace = require('../ProjectWorkspace');
+const ProjectWorkspace = require('../project_workspace');
 
 describe('setup', () => {
   it('sets itself up fom the constructor', () => {
diff --git a/packages/jest-editor-support/src/__tests__/Runner-test.js b/packages/jest-editor-support/src/__tests__/runner.test.js
similarity index 95%
rename from packages/jest-editor-support/src/__tests__/Runner-test.js
rename to packages/jest-editor-support/src/__tests__/runner.test.js
index b0b5dd7b452d..68022edcc81f 100644
--- a/packages/jest-editor-support/src/__tests__/Runner-test.js
+++ b/packages/jest-editor-support/src/__tests__/runner.test.js
@@ -12,7 +12,7 @@ const {EventEmitter} = require('events');
 const path = require('path');
 const {readFileSync} = require('fs');
 const fixtures = path.resolve(__dirname, '../../../../fixtures');
-const ProjectWorkspace = require('../ProjectWorkspace');
+const ProjectWorkspace = require('../project_workspace');
 
 // Replace `readFile` with `readFileSync` so we don't get multiple threads
 jest.doMock('fs', () => {
@@ -28,13 +28,13 @@ jest.doMock('fs', () => {
 // Let's us use a per-test "jest process"
 let mockDebugProcess = {};
 const mockCreateProcess = jest.fn(() => mockDebugProcess);
-jest.doMock('../Process.js', () => {
+jest.doMock('../process.js', () => {
   return {
     createProcess: mockCreateProcess,
   };
 });
 
-const Runner = require('../Runner');
+const Runner = require('../runner');
 
 describe('events', () => {
   let runner;
diff --git a/packages/jest-editor-support/src/__tests__/Settings-test.js b/packages/jest-editor-support/src/__tests__/settings.test.js
similarity index 95%
rename from packages/jest-editor-support/src/__tests__/Settings-test.js
rename to packages/jest-editor-support/src/__tests__/settings.test.js
index 4ad2d52f2222..69a378522323 100644
--- a/packages/jest-editor-support/src/__tests__/Settings-test.js
+++ b/packages/jest-editor-support/src/__tests__/settings.test.js
@@ -9,8 +9,8 @@
 'use strict';
 
 const {EventEmitter} = require('events');
-const ProjectWorkspace = require('../ProjectWorkspace');
-const Settings = require('../Settings');
+const ProjectWorkspace = require('../project_workspace');
+const Settings = require('../settings');
 
 describe('Settings', () => {
   it('sets itself up fom the constructor', () => {
diff --git a/packages/jest-editor-support/src/__tests__/TestReconciler-test.js b/packages/jest-editor-support/src/__tests__/test_reconciler.test.js
similarity index 98%
rename from packages/jest-editor-support/src/__tests__/TestReconciler-test.js
rename to packages/jest-editor-support/src/__tests__/test_reconciler.test.js
index 21bb90f6e3d8..1eabfa6b336e 100644
--- a/packages/jest-editor-support/src/__tests__/TestReconciler-test.js
+++ b/packages/jest-editor-support/src/__tests__/test_reconciler.test.js
@@ -8,7 +8,7 @@
 
 const fs = require('fs');
 const path = require('path');
-const TestReconciler = require('../TestReconciler');
+const TestReconciler = require('../test_reconciler');
 const fixtures = path.resolve(__dirname, '../../../../fixtures');
 
 const reconcilerWithFile = (file: string): TestReconciler => {
diff --git a/packages/jest-editor-support/src/index.js b/packages/jest-editor-support/src/index.js
index d17e7137e03d..2adab1c6c261 100644
--- a/packages/jest-editor-support/src/index.js
+++ b/packages/jest-editor-support/src/index.js
@@ -8,14 +8,14 @@
  * @flow
  */
 
-import Process from './Process';
+import Process from './process';
 
-import ProjectWorkspace from './ProjectWorkspace';
-import Runner from './Runner';
-import Settings from './Settings';
-import {Expect, ItBlock, Node} from './parsers/ParserNodes';
-import {parse} from './parsers/BabylonParser';
-import TestReconciler from './TestReconciler';
+import ProjectWorkspace from './project_workspace';
+import Runner from './runner';
+import Settings from './settings';
+import {Expect, ItBlock, Node} from './parsers/parser_nodes';
+import {parse} from './parsers/babylon_parser';
+import TestReconciler from './test_reconciler';
 
 module.exports = {
   Expect,
diff --git a/packages/jest-editor-support/src/parsers/BabylonParser.js b/packages/jest-editor-support/src/parsers/babylon_parser.js
similarity index 99%
rename from packages/jest-editor-support/src/parsers/BabylonParser.js
rename to packages/jest-editor-support/src/parsers/babylon_parser.js
index 75c921beb607..c25f4f6403ca 100644
--- a/packages/jest-editor-support/src/parsers/BabylonParser.js
+++ b/packages/jest-editor-support/src/parsers/babylon_parser.js
@@ -11,7 +11,7 @@
 import {readFileSync} from 'fs';
 
 import {parse as babylonParse} from 'babylon';
-import {Expect, ItBlock} from './ParserNodes';
+import {Expect, ItBlock} from './parser_nodes';
 
 export type BabylonParserResult = {
   expects: Array<Expect>,
diff --git a/packages/jest-editor-support/src/parsers/ParserNodes.js b/packages/jest-editor-support/src/parsers/parser_nodes.js
similarity index 100%
rename from packages/jest-editor-support/src/parsers/ParserNodes.js
rename to packages/jest-editor-support/src/parsers/parser_nodes.js
diff --git a/packages/jest-editor-support/src/Process.js b/packages/jest-editor-support/src/process.js
similarity index 96%
rename from packages/jest-editor-support/src/Process.js
rename to packages/jest-editor-support/src/process.js
index 5e75f47d6424..e3c057e903af 100644
--- a/packages/jest-editor-support/src/Process.js
+++ b/packages/jest-editor-support/src/process.js
@@ -10,7 +10,7 @@
 
 import {ChildProcess, spawn} from 'child_process';
 
-import ProjectWorkspace from './ProjectWorkspace';
+import ProjectWorkspace from './project_workspace';
 
 /**
  * Spawns and returns a Jest process with specific args
diff --git a/packages/jest-editor-support/src/ProjectWorkspace.js b/packages/jest-editor-support/src/project_workspace.js
similarity index 100%
rename from packages/jest-editor-support/src/ProjectWorkspace.js
rename to packages/jest-editor-support/src/project_workspace.js
diff --git a/packages/jest-editor-support/src/Runner.js b/packages/jest-editor-support/src/runner.js
similarity index 97%
rename from packages/jest-editor-support/src/Runner.js
rename to packages/jest-editor-support/src/runner.js
index 4643b94fd0a2..a53d5219c910 100644
--- a/packages/jest-editor-support/src/Runner.js
+++ b/packages/jest-editor-support/src/runner.js
@@ -14,8 +14,8 @@ import {ChildProcess, spawn} from 'child_process';
 import {readFile} from 'fs';
 import {tmpdir} from 'os';
 import EventEmitter from 'events';
-import ProjectWorkspace from './ProjectWorkspace';
-import {createProcess} from './Process';
+import ProjectWorkspace from './project_workspace';
+import {createProcess} from './process';
 
 // This class represents the running process, and
 // passes out events when it understands what data is being
diff --git a/packages/jest-editor-support/src/Settings.js b/packages/jest-editor-support/src/settings.js
similarity index 96%
rename from packages/jest-editor-support/src/Settings.js
rename to packages/jest-editor-support/src/settings.js
index 9f7eda88c31d..79ef2b3bc75d 100644
--- a/packages/jest-editor-support/src/Settings.js
+++ b/packages/jest-editor-support/src/settings.js
@@ -12,8 +12,8 @@ import type {Options} from './types';
 
 import {ChildProcess} from 'child_process';
 import EventEmitter from 'events';
-import ProjectWorkspace from './ProjectWorkspace';
-import {createProcess} from './Process';
+import ProjectWorkspace from './project_workspace';
+import {createProcess} from './process';
 
 // This class represents the the configuration of Jest's process
 // we want to start with the defaults then override whatever they output
diff --git a/packages/jest-editor-support/src/TestReconciler.js b/packages/jest-editor-support/src/test_reconciler.js
similarity index 100%
rename from packages/jest-editor-support/src/TestReconciler.js
rename to packages/jest-editor-support/src/test_reconciler.js
diff --git a/packages/jest-editor-support/src/types.js b/packages/jest-editor-support/src/types.js
index 7ce478e7c911..ea92ce9f7397 100644
--- a/packages/jest-editor-support/src/types.js
+++ b/packages/jest-editor-support/src/types.js
@@ -14,7 +14,7 @@ export type Location = {
 };
 
 import type {ChildProcess} from 'child_process';
-import type ProjectWorkspace from './ProjectWorkspace';
+import type ProjectWorkspace from './project_workspace';
 
 export type Options = {
   createProcess?: (
diff --git a/packages/jest-environment-node/src/__tests__/NodeEnvironment-test.js b/packages/jest-environment-node/src/__tests__/node_environment.test.js
similarity index 100%
rename from packages/jest-environment-node/src/__tests__/NodeEnvironment-test.js
rename to packages/jest-environment-node/src/__tests__/node_environment.test.js
diff --git a/packages/jest-get-type/src/__tests__/index-test.js b/packages/jest-get-type/src/__tests__/index.test.js
similarity index 100%
rename from packages/jest-get-type/src/__tests__/index-test.js
rename to packages/jest-get-type/src/__tests__/index.test.js
diff --git a/packages/jest-haste-map/src/__tests__/__snapshots__/index-test.js.snap b/packages/jest-haste-map/src/__tests__/__snapshots__/index.test.js.snap
similarity index 100%
rename from packages/jest-haste-map/src/__tests__/__snapshots__/index-test.js.snap
rename to packages/jest-haste-map/src/__tests__/__snapshots__/index.test.js.snap
diff --git a/packages/jest-haste-map/src/__tests__/getMockName-test.js b/packages/jest-haste-map/src/__tests__/get_mock_name.test.js
similarity index 92%
rename from packages/jest-haste-map/src/__tests__/getMockName-test.js
rename to packages/jest-haste-map/src/__tests__/get_mock_name.test.js
index 51d31a067066..ac008008e566 100644
--- a/packages/jest-haste-map/src/__tests__/getMockName-test.js
+++ b/packages/jest-haste-map/src/__tests__/get_mock_name.test.js
@@ -9,7 +9,7 @@
 'use strict';
 
 const path = require('path');
-const getMockName = require('../getMockName');
+const getMockName = require('../get_mock_name');
 
 describe('getMockName', () => {
   it('extracts mock name from file path', () => {
diff --git a/packages/jest-haste-map/src/__tests__/index-test.js b/packages/jest-haste-map/src/__tests__/index.test.js
similarity index 100%
rename from packages/jest-haste-map/src/__tests__/index-test.js
rename to packages/jest-haste-map/src/__tests__/index.test.js
diff --git a/packages/jest-haste-map/src/__tests__/worker-test.js b/packages/jest-haste-map/src/__tests__/worker.test.js
similarity index 100%
rename from packages/jest-haste-map/src/__tests__/worker-test.js
rename to packages/jest-haste-map/src/__tests__/worker.test.js
diff --git a/packages/jest-haste-map/src/crawlers/__tests__/node-test.js b/packages/jest-haste-map/src/crawlers/__tests__/node.test.js
similarity index 100%
rename from packages/jest-haste-map/src/crawlers/__tests__/node-test.js
rename to packages/jest-haste-map/src/crawlers/__tests__/node.test.js
diff --git a/packages/jest-haste-map/src/crawlers/__tests__/watchman-test.js b/packages/jest-haste-map/src/crawlers/__tests__/watchman.test.js
similarity index 100%
rename from packages/jest-haste-map/src/crawlers/__tests__/watchman-test.js
rename to packages/jest-haste-map/src/crawlers/__tests__/watchman.test.js
diff --git a/packages/jest-haste-map/src/getMockName.js b/packages/jest-haste-map/src/get_mock_name.js
similarity index 100%
rename from packages/jest-haste-map/src/getMockName.js
rename to packages/jest-haste-map/src/get_mock_name.js
diff --git a/packages/jest-haste-map/src/HasteFS.js b/packages/jest-haste-map/src/haste_fs.js
similarity index 100%
rename from packages/jest-haste-map/src/HasteFS.js
rename to packages/jest-haste-map/src/haste_fs.js
diff --git a/packages/jest-haste-map/src/index.js b/packages/jest-haste-map/src/index.js
index f1d189c4a2b4..77ef019a5652 100644
--- a/packages/jest-haste-map/src/index.js
+++ b/packages/jest-haste-map/src/index.js
@@ -33,10 +33,10 @@ import workerFarm from 'worker-farm';
 import {version as VERSION} from '../package.json';
 // eslint-disable-next-line import/no-duplicates
 import H from './constants';
-import HasteFS from './HasteFS';
-import HasteModuleMap from './ModuleMap';
-import getMockName from './getMockName';
-import getPlatformExtension from './lib/getPlatformExtension';
+import HasteFS from './haste_fs';
+import HasteModuleMap from './module_map';
+import getMockName from './get_mock_name';
+import getPlatformExtension from './lib/get_platform_extension';
 import nodeCrawl from './crawlers/node';
 import watchmanCrawl from './crawlers/watchman';
 import worker from './worker';
diff --git a/packages/jest-haste-map/src/lib/__tests__/extractRequires-test.js b/packages/jest-haste-map/src/lib/__tests__/extract_requires.test.js
similarity index 97%
rename from packages/jest-haste-map/src/lib/__tests__/extractRequires-test.js
rename to packages/jest-haste-map/src/lib/__tests__/extract_requires.test.js
index bcc103a21dcf..fb470813bde5 100644
--- a/packages/jest-haste-map/src/lib/__tests__/extractRequires-test.js
+++ b/packages/jest-haste-map/src/lib/__tests__/extract_requires.test.js
@@ -10,7 +10,7 @@
  */
 'use strict';
 
-const extractRequires = require('../extractRequires');
+const extractRequires = require('../extract_requires');
 
 describe('extractRequires', () => {
   it('extracts both requires and imports from code', () => {
diff --git a/packages/jest-haste-map/src/lib/__tests__/getPlatformExtension-test.js b/packages/jest-haste-map/src/lib/__tests__/get_platform_extension.test.js
similarity index 93%
rename from packages/jest-haste-map/src/lib/__tests__/getPlatformExtension-test.js
rename to packages/jest-haste-map/src/lib/__tests__/get_platform_extension.test.js
index 15ddc5c062db..e300392ecf8b 100644
--- a/packages/jest-haste-map/src/lib/__tests__/getPlatformExtension-test.js
+++ b/packages/jest-haste-map/src/lib/__tests__/get_platform_extension.test.js
@@ -14,7 +14,7 @@ let getPlatformExtension;
 
 describe('getPlatformExtension', () => {
   beforeEach(() => {
-    getPlatformExtension = require('../getPlatformExtension');
+    getPlatformExtension = require('../get_platform_extension');
   });
 
   it('should get platform ext', () => {
diff --git a/packages/jest-haste-map/src/lib/extractRequires.js b/packages/jest-haste-map/src/lib/extract_requires.js
similarity index 100%
rename from packages/jest-haste-map/src/lib/extractRequires.js
rename to packages/jest-haste-map/src/lib/extract_requires.js
diff --git a/packages/jest-haste-map/src/lib/getPlatformExtension.js b/packages/jest-haste-map/src/lib/get_platform_extension.js
similarity index 100%
rename from packages/jest-haste-map/src/lib/getPlatformExtension.js
rename to packages/jest-haste-map/src/lib/get_platform_extension.js
diff --git a/packages/jest-haste-map/src/ModuleMap.js b/packages/jest-haste-map/src/module_map.js
similarity index 100%
rename from packages/jest-haste-map/src/ModuleMap.js
rename to packages/jest-haste-map/src/module_map.js
diff --git a/packages/jest-haste-map/src/worker.js b/packages/jest-haste-map/src/worker.js
index 9cc6c55e8bc6..9bf52cb3968f 100644
--- a/packages/jest-haste-map/src/worker.js
+++ b/packages/jest-haste-map/src/worker.js
@@ -15,7 +15,7 @@ import path from 'path';
 import docblock from 'jest-docblock';
 import fs from 'graceful-fs';
 import H from './constants';
-import extractRequires from './lib/extractRequires';
+import extractRequires from './lib/extract_requires';
 
 const JSON_EXTENSION = '.json';
 const PACKAGE_JSON = path.sep + 'package' + JSON_EXTENSION;
diff --git a/packages/jest-jasmine2/src/__tests__/__snapshots__/expectationResultFactory-test.js.snap b/packages/jest-jasmine2/src/__tests__/__snapshots__/expectation_result_factory.test.js.snap
similarity index 100%
rename from packages/jest-jasmine2/src/__tests__/__snapshots__/expectationResultFactory-test.js.snap
rename to packages/jest-jasmine2/src/__tests__/__snapshots__/expectation_result_factory.test.js.snap
diff --git a/packages/jest-jasmine2/src/__tests__/__snapshots__/matchers-test.js.snap b/packages/jest-jasmine2/src/__tests__/__snapshots__/matchers.test.js.snap
similarity index 100%
rename from packages/jest-jasmine2/src/__tests__/__snapshots__/matchers-test.js.snap
rename to packages/jest-jasmine2/src/__tests__/__snapshots__/matchers.test.js.snap
diff --git a/packages/jest-jasmine2/src/__tests__/expectationResultFactory-test.js b/packages/jest-jasmine2/src/__tests__/expectation_result_factory.test.js
similarity index 96%
rename from packages/jest-jasmine2/src/__tests__/expectationResultFactory-test.js
rename to packages/jest-jasmine2/src/__tests__/expectation_result_factory.test.js
index 30f1ac811579..5e731da5584d 100644
--- a/packages/jest-jasmine2/src/__tests__/expectationResultFactory-test.js
+++ b/packages/jest-jasmine2/src/__tests__/expectation_result_factory.test.js
@@ -9,7 +9,7 @@
  */
 'use strict';
 
-const expectationResultFactory = require('../expectationResultFactory');
+const expectationResultFactory = require('../expectation_result_factory');
 
 describe('expectationResultFactory', () => {
   it('returns the result if passed.', () => {
diff --git a/packages/jest-jasmine2/src/__tests__/it_to_test_alias-test.js b/packages/jest-jasmine2/src/__tests__/it_to_test_alias.test.js
similarity index 100%
rename from packages/jest-jasmine2/src/__tests__/it_to_test_alias-test.js
rename to packages/jest-jasmine2/src/__tests__/it_to_test_alias.test.js
diff --git a/packages/jest-jasmine2/src/__tests__/iterators-test.js b/packages/jest-jasmine2/src/__tests__/iterators.test.js
similarity index 100%
rename from packages/jest-jasmine2/src/__tests__/iterators-test.js
rename to packages/jest-jasmine2/src/__tests__/iterators.test.js
diff --git a/packages/jest-jasmine2/src/__tests__/matchers-test.js b/packages/jest-jasmine2/src/__tests__/matchers.test.js
similarity index 100%
rename from packages/jest-jasmine2/src/__tests__/matchers-test.js
rename to packages/jest-jasmine2/src/__tests__/matchers.test.js
diff --git a/packages/jest-jasmine2/src/__tests__/p-timeout-test.js b/packages/jest-jasmine2/src/__tests__/p_timeout.test.js
similarity index 97%
rename from packages/jest-jasmine2/src/__tests__/p-timeout-test.js
rename to packages/jest-jasmine2/src/__tests__/p_timeout.test.js
index 28da9dcc50be..e61fa97bbe85 100644
--- a/packages/jest-jasmine2/src/__tests__/p-timeout-test.js
+++ b/packages/jest-jasmine2/src/__tests__/p_timeout.test.js
@@ -11,7 +11,7 @@
 
 jest.useFakeTimers();
 
-const pTimeout = require('../p-timeout');
+const pTimeout = require('../p_timeout');
 
 describe('pTimeout', () => {
   it('calls `clearTimeout` and resolves when `promise` resolves.', async () => {
diff --git a/packages/jest-jasmine2/src/__tests__/queueRunner-test.js b/packages/jest-jasmine2/src/__tests__/queue_runner.test.js
similarity index 98%
rename from packages/jest-jasmine2/src/__tests__/queueRunner-test.js
rename to packages/jest-jasmine2/src/__tests__/queue_runner.test.js
index dbedb86e239f..5c7758a8adda 100644
--- a/packages/jest-jasmine2/src/__tests__/queueRunner-test.js
+++ b/packages/jest-jasmine2/src/__tests__/queue_runner.test.js
@@ -9,7 +9,7 @@
  */
 'use strict';
 
-const queueRunner = require('../queueRunner');
+const queueRunner = require('../queue_runner');
 
 describe('queueRunner', () => {
   it('runs every function in the queue.', async () => {
diff --git a/packages/jest-jasmine2/src/__tests__/reporter-test.js b/packages/jest-jasmine2/src/__tests__/reporter.test.js
similarity index 100%
rename from packages/jest-jasmine2/src/__tests__/reporter-test.js
rename to packages/jest-jasmine2/src/__tests__/reporter.test.js
diff --git a/packages/jest-jasmine2/src/assert-support.js b/packages/jest-jasmine2/src/assert_support.js
similarity index 98%
rename from packages/jest-jasmine2/src/assert-support.js
rename to packages/jest-jasmine2/src/assert_support.js
index 342acc751bd5..ba45a338e533 100644
--- a/packages/jest-jasmine2/src/assert-support.js
+++ b/packages/jest-jasmine2/src/assert_support.js
@@ -8,7 +8,7 @@
  * @flow
  */
 
-import type {DiffOptions} from 'jest-diff/src/diffStrings';
+import type {DiffOptions} from 'jest-diff/src/diff_strings';
 
 import {printReceived, printExpected} from 'jest-matcher-utils';
 import chalk from 'chalk';
diff --git a/packages/jest-jasmine2/src/ExpectationFailed.js b/packages/jest-jasmine2/src/expectation_failed.js
similarity index 100%
rename from packages/jest-jasmine2/src/ExpectationFailed.js
rename to packages/jest-jasmine2/src/expectation_failed.js
diff --git a/packages/jest-jasmine2/src/expectationResultFactory.js b/packages/jest-jasmine2/src/expectation_result_factory.js
similarity index 100%
rename from packages/jest-jasmine2/src/expectationResultFactory.js
rename to packages/jest-jasmine2/src/expectation_result_factory.js
diff --git a/packages/jest-jasmine2/src/index.js b/packages/jest-jasmine2/src/index.js
index 3bc83cc60045..642492817351 100644
--- a/packages/jest-jasmine2/src/index.js
+++ b/packages/jest-jasmine2/src/index.js
@@ -16,9 +16,9 @@ import type Runtime from 'jest-runtime';
 
 import path from 'path';
 import JasmineReporter from './reporter';
-import jasmineAsync from './jasmine-async';
+import jasmineAsync from './jasmine_async';
 
-const JASMINE = require.resolve('./jasmine/jasmine-light.js');
+const JASMINE = require.resolve('./jasmine/jasmine_light.js');
 
 async function jasmine2(
   globalConfig: GlobalConfig,
@@ -74,12 +74,12 @@ async function jasmine2(
 
   env.addReporter(reporter);
 
-  runtime.requireInternalModule(path.resolve(__dirname, './jest-expect.js'))({
+  runtime.requireInternalModule(path.resolve(__dirname, './jest_expect.js'))({
     expand: globalConfig.expand,
   });
 
   const snapshotState: SnapshotState = runtime.requireInternalModule(
-    path.resolve(__dirname, './setup-jest-globals.js'),
+    path.resolve(__dirname, './setup_jest_globals.js'),
   )({
     config,
     globalConfig,
diff --git a/packages/jest-jasmine2/src/jasmine/CallTracker.js b/packages/jest-jasmine2/src/jasmine/call_tracker.js
similarity index 100%
rename from packages/jest-jasmine2/src/jasmine/CallTracker.js
rename to packages/jest-jasmine2/src/jasmine/call_tracker.js
diff --git a/packages/jest-jasmine2/src/jasmine/createSpy.js b/packages/jest-jasmine2/src/jasmine/create_spy.js
similarity index 96%
rename from packages/jest-jasmine2/src/jasmine/createSpy.js
rename to packages/jest-jasmine2/src/jasmine/create_spy.js
index 8af4ed56bc06..d3f93ad8e2d2 100644
--- a/packages/jest-jasmine2/src/jasmine/createSpy.js
+++ b/packages/jest-jasmine2/src/jasmine/create_spy.js
@@ -31,9 +31,9 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
 /* eslint-disable sort-keys */
 
-import CallTracker from './CallTracker';
+import CallTracker from './call_tracker';
 
-import SpyStrategy from './SpyStrategy';
+import SpyStrategy from './spy_strategy';
 
 function createSpy(name, originalFn) {
   const spyStrategy = new SpyStrategy({
diff --git a/packages/jest-jasmine2/src/jasmine/Env.js b/packages/jest-jasmine2/src/jasmine/env.js
similarity index 99%
rename from packages/jest-jasmine2/src/jasmine/Env.js
rename to packages/jest-jasmine2/src/jasmine/env.js
index 3abd06e18195..2a0ad062806e 100644
--- a/packages/jest-jasmine2/src/jasmine/Env.js
+++ b/packages/jest-jasmine2/src/jasmine/env.js
@@ -31,9 +31,9 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
 /* eslint-disable sort-keys */
 
-import queueRunner from '../queueRunner';
+import queueRunner from '../queue_runner';
 
-import treeProcessor from '../treeProcessor';
+import treeProcessor from '../tree_processor';
 
 module.exports = function(j$) {
   function Env(options) {
diff --git a/packages/jest-jasmine2/src/jasmine/jasmine-light.js b/packages/jest-jasmine2/src/jasmine/jasmine_light.js
similarity index 92%
rename from packages/jest-jasmine2/src/jasmine/jasmine-light.js
rename to packages/jest-jasmine2/src/jasmine/jasmine_light.js
index abb2f7cb5f11..5f7142d77490 100644
--- a/packages/jest-jasmine2/src/jasmine/jasmine-light.js
+++ b/packages/jest-jasmine2/src/jasmine/jasmine_light.js
@@ -34,14 +34,14 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 import type {Jasmine} from 'types/Jasmine';
 
-import createSpy from './createSpy';
-import Env from './Env';
-import JsApiReporter from './JsApiReporter';
-import ReportDispatcher from './ReportDispatcher';
-import Spec from './Spec';
-import SpyRegistry from './SpyRegistry';
-import Suite from './Suite';
-import Timer from './Timer';
+import createSpy from './create_spy';
+import Env from './env';
+import JsApiReporter from './js_api_reporter';
+import ReportDispatcher from './report_dispatcher';
+import Spec from './spec';
+import SpyRegistry from './spy_registry';
+import Suite from './suite';
+import Timer from './timer';
 
 exports.create = function() {
   const j$ = {};
diff --git a/packages/jest-jasmine2/src/jasmine/JsApiReporter.js b/packages/jest-jasmine2/src/jasmine/js_api_reporter.js
similarity index 100%
rename from packages/jest-jasmine2/src/jasmine/JsApiReporter.js
rename to packages/jest-jasmine2/src/jasmine/js_api_reporter.js
diff --git a/packages/jest-jasmine2/src/jasmine/ReportDispatcher.js b/packages/jest-jasmine2/src/jasmine/report_dispatcher.js
similarity index 100%
rename from packages/jest-jasmine2/src/jasmine/ReportDispatcher.js
rename to packages/jest-jasmine2/src/jasmine/report_dispatcher.js
diff --git a/packages/jest-jasmine2/src/jasmine/Spec.js b/packages/jest-jasmine2/src/jasmine/spec.js
similarity index 96%
rename from packages/jest-jasmine2/src/jasmine/Spec.js
rename to packages/jest-jasmine2/src/jasmine/spec.js
index b8a36726d5e8..c74218c2450b 100644
--- a/packages/jest-jasmine2/src/jasmine/Spec.js
+++ b/packages/jest-jasmine2/src/jasmine/spec.js
@@ -32,9 +32,9 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 /* @flow */
 /* eslint-disable sort-keys */
 
-import ExpectationFailed from '../ExpectationFailed';
+import ExpectationFailed from '../expectation_failed';
 
-import expectationResultFactory from '../expectationResultFactory';
+import expectationResultFactory from '../expectation_result_factory';
 
 function Spec(attrs: Object) {
   this.resultCallback = attrs.resultCallback || function() {};
@@ -125,7 +125,7 @@ Spec.prototype.onException = function onException(error) {
   }
 
   if (error instanceof require('assert').AssertionError) {
-    const assertionErrorMessage = require('../assert-support');
+    const assertionErrorMessage = require('../assert_support');
     error = assertionErrorMessage(error, {expand: this.expand});
   }
 
diff --git a/packages/jest-jasmine2/src/jasmine/SpyRegistry.js b/packages/jest-jasmine2/src/jasmine/spy_registry.js
similarity index 97%
rename from packages/jest-jasmine2/src/jasmine/SpyRegistry.js
rename to packages/jest-jasmine2/src/jasmine/spy_registry.js
index 7667f68b2c48..5d588079b8d2 100644
--- a/packages/jest-jasmine2/src/jasmine/SpyRegistry.js
+++ b/packages/jest-jasmine2/src/jasmine/spy_registry.js
@@ -31,10 +31,10 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
 /* @flow */
 
-import CallTracker from './CallTracker';
+import CallTracker from './call_tracker';
 
-import createSpy from './createSpy';
-import SpyStrategy from './SpyStrategy';
+import createSpy from './create_spy';
+import SpyStrategy from './spy_strategy';
 
 const formatErrorMsg = (domain: string, usage?: string) => {
   const usageDefinition = usage ? '\nUsage: ' + usage : '';
diff --git a/packages/jest-jasmine2/src/jasmine/SpyStrategy.js b/packages/jest-jasmine2/src/jasmine/spy_strategy.js
similarity index 100%
rename from packages/jest-jasmine2/src/jasmine/SpyStrategy.js
rename to packages/jest-jasmine2/src/jasmine/spy_strategy.js
diff --git a/packages/jest-jasmine2/src/jasmine/Suite.js b/packages/jest-jasmine2/src/jasmine/suite.js
similarity index 97%
rename from packages/jest-jasmine2/src/jasmine/Suite.js
rename to packages/jest-jasmine2/src/jasmine/suite.js
index 83449e3573cf..8d511602c58a 100644
--- a/packages/jest-jasmine2/src/jasmine/Suite.js
+++ b/packages/jest-jasmine2/src/jasmine/suite.js
@@ -32,9 +32,9 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 /* @flow */
 /* eslint-disable sort-keys */
 
-import ExpectationFailed from '../ExpectationFailed';
+import ExpectationFailed from '../expectation_failed';
 
-import expectationResultFactory from '../expectationResultFactory';
+import expectationResultFactory from '../expectation_result_factory';
 
 function Suite(attrs: Object) {
   this.id = attrs.id;
diff --git a/packages/jest-jasmine2/src/jasmine/Timer.js b/packages/jest-jasmine2/src/jasmine/timer.js
similarity index 100%
rename from packages/jest-jasmine2/src/jasmine/Timer.js
rename to packages/jest-jasmine2/src/jasmine/timer.js
diff --git a/packages/jest-jasmine2/src/jasmine-async.js b/packages/jest-jasmine2/src/jasmine_async.js
similarity index 100%
rename from packages/jest-jasmine2/src/jasmine-async.js
rename to packages/jest-jasmine2/src/jasmine_async.js
diff --git a/packages/jest-jasmine2/src/jest-expect.js b/packages/jest-jasmine2/src/jest_expect.js
similarity index 100%
rename from packages/jest-jasmine2/src/jest-expect.js
rename to packages/jest-jasmine2/src/jest_expect.js
diff --git a/packages/jest-jasmine2/src/p-timeout.js b/packages/jest-jasmine2/src/p_timeout.js
similarity index 100%
rename from packages/jest-jasmine2/src/p-timeout.js
rename to packages/jest-jasmine2/src/p_timeout.js
diff --git a/packages/jest-jasmine2/src/queueRunner.js b/packages/jest-jasmine2/src/queue_runner.js
similarity index 97%
rename from packages/jest-jasmine2/src/queueRunner.js
rename to packages/jest-jasmine2/src/queue_runner.js
index 893389bb3b9e..57309120300a 100644
--- a/packages/jest-jasmine2/src/queueRunner.js
+++ b/packages/jest-jasmine2/src/queue_runner.js
@@ -8,7 +8,7 @@
  * @flow
  */
 
-import pTimeout from './p-timeout';
+import pTimeout from './p_timeout';
 
 type Options = {
   clearTimeout: (timeoutID: number) => void,
diff --git a/packages/jest-jasmine2/src/setup-jest-globals.js b/packages/jest-jasmine2/src/setup_jest_globals.js
similarity index 100%
rename from packages/jest-jasmine2/src/setup-jest-globals.js
rename to packages/jest-jasmine2/src/setup_jest_globals.js
diff --git a/packages/jest-jasmine2/src/treeProcessor.js b/packages/jest-jasmine2/src/tree_processor.js
similarity index 100%
rename from packages/jest-jasmine2/src/treeProcessor.js
rename to packages/jest-jasmine2/src/tree_processor.js
diff --git a/packages/jest-matcher-utils/src/__tests__/__snapshots__/index-test.js.snap b/packages/jest-matcher-utils/src/__tests__/__snapshots__/index.test.js.snap
similarity index 100%
rename from packages/jest-matcher-utils/src/__tests__/__snapshots__/index-test.js.snap
rename to packages/jest-matcher-utils/src/__tests__/__snapshots__/index.test.js.snap
diff --git a/packages/jest-matcher-utils/src/__tests__/index-test.js b/packages/jest-matcher-utils/src/__tests__/index.test.js
similarity index 100%
rename from packages/jest-matcher-utils/src/__tests__/index-test.js
rename to packages/jest-matcher-utils/src/__tests__/index.test.js
diff --git a/packages/jest-matchers/src/__tests__/__snapshots__/extend-test.js.snap b/packages/jest-matchers/src/__tests__/__snapshots__/extend.test.js.snap
similarity index 100%
rename from packages/jest-matchers/src/__tests__/__snapshots__/extend-test.js.snap
rename to packages/jest-matchers/src/__tests__/__snapshots__/extend.test.js.snap
diff --git a/packages/jest-matchers/src/__tests__/__snapshots__/matchers-test.js.snap b/packages/jest-matchers/src/__tests__/__snapshots__/matchers.test.js.snap
similarity index 100%
rename from packages/jest-matchers/src/__tests__/__snapshots__/matchers-test.js.snap
rename to packages/jest-matchers/src/__tests__/__snapshots__/matchers.test.js.snap
diff --git a/packages/jest-matchers/src/__tests__/__snapshots__/spyMatchers-test.js.snap b/packages/jest-matchers/src/__tests__/__snapshots__/spy_matchers.test.js.snap
similarity index 100%
rename from packages/jest-matchers/src/__tests__/__snapshots__/spyMatchers-test.js.snap
rename to packages/jest-matchers/src/__tests__/__snapshots__/spy_matchers.test.js.snap
diff --git a/packages/jest-matchers/src/__tests__/__snapshots__/toThrowMatchers-test.js.snap b/packages/jest-matchers/src/__tests__/__snapshots__/to_throw_matchers.test.js.snap
similarity index 100%
rename from packages/jest-matchers/src/__tests__/__snapshots__/toThrowMatchers-test.js.snap
rename to packages/jest-matchers/src/__tests__/__snapshots__/to_throw_matchers.test.js.snap
diff --git a/packages/jest-matchers/src/__tests__/assertion-counts-test.js b/packages/jest-matchers/src/__tests__/assertion_counts.test.js
similarity index 100%
rename from packages/jest-matchers/src/__tests__/assertion-counts-test.js
rename to packages/jest-matchers/src/__tests__/assertion_counts.test.js
diff --git a/packages/jest-matchers/src/__tests__/asymmetric-matchers-test.js b/packages/jest-matchers/src/__tests__/asymmetric_matchers.test.js
similarity index 99%
rename from packages/jest-matchers/src/__tests__/asymmetric-matchers-test.js
rename to packages/jest-matchers/src/__tests__/asymmetric_matchers.test.js
index b189a99b224d..7e2d046b716f 100644
--- a/packages/jest-matchers/src/__tests__/asymmetric-matchers-test.js
+++ b/packages/jest-matchers/src/__tests__/asymmetric_matchers.test.js
@@ -18,7 +18,7 @@ const {
   objectContaining,
   stringContaining,
   stringMatching,
-} = require('../asymmetric-matchers');
+} = require('../asymmetric_matchers');
 
 test('Any.asymmetricMatch()', () => {
   const Thing = function() {};
diff --git a/packages/jest-matchers/src/__tests__/extend-test.js b/packages/jest-matchers/src/__tests__/extend.test.js
similarity index 97%
rename from packages/jest-matchers/src/__tests__/extend-test.js
rename to packages/jest-matchers/src/__tests__/extend.test.js
index 32bc1186d09b..f864e693e3e9 100644
--- a/packages/jest-matchers/src/__tests__/extend-test.js
+++ b/packages/jest-matchers/src/__tests__/extend.test.js
@@ -9,7 +9,7 @@
  */
 
 const matcherUtils = require('jest-matcher-utils');
-const {equals} = require('../jasmine-utils');
+const {equals} = require('../jasmine_utils');
 const jestExpect = require('../');
 
 jestExpect.extend({
diff --git a/packages/jest-matchers/src/__tests__/matchers-test.js b/packages/jest-matchers/src/__tests__/matchers.test.js
similarity index 100%
rename from packages/jest-matchers/src/__tests__/matchers-test.js
rename to packages/jest-matchers/src/__tests__/matchers.test.js
diff --git a/packages/jest-matchers/src/__tests__/spyMatchers-test.js b/packages/jest-matchers/src/__tests__/spy_matchers.test.js
similarity index 100%
rename from packages/jest-matchers/src/__tests__/spyMatchers-test.js
rename to packages/jest-matchers/src/__tests__/spy_matchers.test.js
diff --git a/packages/jest-matchers/src/__tests__/symbol-in-objects-test.js b/packages/jest-matchers/src/__tests__/symbol_in_objects.test.js
similarity index 100%
rename from packages/jest-matchers/src/__tests__/symbol-in-objects-test.js
rename to packages/jest-matchers/src/__tests__/symbol_in_objects.test.js
diff --git a/packages/jest-matchers/src/__tests__/toThrowMatchers-test.js b/packages/jest-matchers/src/__tests__/to_throw_matchers.test.js
similarity index 100%
rename from packages/jest-matchers/src/__tests__/toThrowMatchers-test.js
rename to packages/jest-matchers/src/__tests__/to_throw_matchers.test.js
diff --git a/packages/jest-matchers/src/__tests__/utils-test.js b/packages/jest-matchers/src/__tests__/utils.test.js
similarity index 100%
rename from packages/jest-matchers/src/__tests__/utils-test.js
rename to packages/jest-matchers/src/__tests__/utils.test.js
diff --git a/packages/jest-matchers/src/asymmetric-matchers.js b/packages/jest-matchers/src/asymmetric_matchers.js
similarity index 99%
rename from packages/jest-matchers/src/asymmetric-matchers.js
rename to packages/jest-matchers/src/asymmetric_matchers.js
index e71f49ce0740..2f96075cf8f7 100644
--- a/packages/jest-matchers/src/asymmetric-matchers.js
+++ b/packages/jest-matchers/src/asymmetric_matchers.js
@@ -14,7 +14,7 @@ import {
   hasProperty,
   isA,
   isUndefined,
-} from './jasmine-utils';
+} from './jasmine_utils';
 
 class AsymmetricMatcher {
   $$typeof: Symbol;
diff --git a/packages/jest-matchers/src/extractExpectedAssertionsErrors.js b/packages/jest-matchers/src/extract_expected_assertions_errors.js
similarity index 97%
rename from packages/jest-matchers/src/extractExpectedAssertionsErrors.js
rename to packages/jest-matchers/src/extract_expected_assertions_errors.js
index 01061e6f00ec..7584dbbc147f 100644
--- a/packages/jest-matchers/src/extractExpectedAssertionsErrors.js
+++ b/packages/jest-matchers/src/extract_expected_assertions_errors.js
@@ -15,7 +15,7 @@ import {
   pluralize,
 } from 'jest-matcher-utils';
 
-import {getState, setState} from './jest-matchers-object';
+import {getState, setState} from './jest_matchers_object';
 
 // Create and format all errors related to the mismatched number of `expect`
 // calls and reset the matchers state.
diff --git a/packages/jest-matchers/src/index.js b/packages/jest-matchers/src/index.js
index 7f4f12f225f3..1ade4c63bb99 100644
--- a/packages/jest-matchers/src/index.js
+++ b/packages/jest-matchers/src/index.js
@@ -21,9 +21,9 @@ import type {
 
 import utils from 'jest-matcher-utils';
 import matchers from './matchers';
-import spyMatchers from './spyMatchers';
-import toThrowMatchers from './toThrowMatchers';
-import {equals} from './jasmine-utils';
+import spyMatchers from './spy_matchers';
+import toThrowMatchers from './to_throw_matchers';
+import {equals} from './jasmine_utils';
 import {
   any,
   anything,
@@ -31,14 +31,15 @@ import {
   objectContaining,
   stringContaining,
   stringMatching,
-} from './asymmetric-matchers';
+} from './asymmetric_matchers';
 import {
   getState,
   setState,
   getMatchers,
   setMatchers,
-} from './jest-matchers-object';
-import extractExpectedAssertionsErrors from './extractExpectedAssertionsErrors';
+} from './jest_matchers_object';
+import extractExpectedAssertionsErrors
+  from './extract_expected_assertions_errors';
 
 class JestAssertionError extends Error {
   matcherResult: any;
diff --git a/packages/jest-matchers/src/jasmine-utils.js b/packages/jest-matchers/src/jasmine_utils.js
similarity index 100%
rename from packages/jest-matchers/src/jasmine-utils.js
rename to packages/jest-matchers/src/jasmine_utils.js
diff --git a/packages/jest-matchers/src/jest-matchers-object.js b/packages/jest-matchers/src/jest_matchers_object.js
similarity index 100%
rename from packages/jest-matchers/src/jest-matchers-object.js
rename to packages/jest-matchers/src/jest_matchers_object.js
diff --git a/packages/jest-matchers/src/matchers.js b/packages/jest-matchers/src/matchers.js
index 67c40656bfcb..4116c0e453ba 100644
--- a/packages/jest-matchers/src/matchers.js
+++ b/packages/jest-matchers/src/matchers.js
@@ -24,7 +24,7 @@ import {
   printWithType,
 } from 'jest-matcher-utils';
 import {getObjectSubset, getPath, hasOwnProperty} from './utils';
-import {equals} from './jasmine-utils';
+import {equals} from './jasmine_utils';
 
 type ContainIterable =
   | Array<any>
diff --git a/packages/jest-matchers/src/spyMatchers.js b/packages/jest-matchers/src/spy_matchers.js
similarity index 99%
rename from packages/jest-matchers/src/spyMatchers.js
rename to packages/jest-matchers/src/spy_matchers.js
index 035f79ce82bf..c1a68be217fc 100644
--- a/packages/jest-matchers/src/spyMatchers.js
+++ b/packages/jest-matchers/src/spy_matchers.js
@@ -23,7 +23,7 @@ import {
   printWithType,
   RECEIVED_COLOR,
 } from 'jest-matcher-utils';
-import {equals} from './jasmine-utils';
+import {equals} from './jasmine_utils';
 
 const RECEIVED_NAME = {
   'mock function': 'jest.fn()',
diff --git a/packages/jest-matchers/src/toThrowMatchers.js b/packages/jest-matchers/src/to_throw_matchers.js
similarity index 99%
rename from packages/jest-matchers/src/toThrowMatchers.js
rename to packages/jest-matchers/src/to_throw_matchers.js
index 9673395b1332..8b074fb53b5e 100644
--- a/packages/jest-matchers/src/toThrowMatchers.js
+++ b/packages/jest-matchers/src/to_throw_matchers.js
@@ -21,7 +21,7 @@ import {
   printExpected,
   printWithType,
 } from 'jest-matcher-utils';
-import {equals} from './jasmine-utils';
+import {equals} from './jasmine_utils';
 
 const createMatcher = matcherName => (
   actual: Function,
diff --git a/packages/jest-message-util/src/__tests__/__snapshots__/messages-test.js.snap b/packages/jest-message-util/src/__tests__/__snapshots__/messages.test.js.snap
similarity index 100%
rename from packages/jest-message-util/src/__tests__/__snapshots__/messages-test.js.snap
rename to packages/jest-message-util/src/__tests__/__snapshots__/messages.test.js.snap
diff --git a/packages/jest-message-util/src/__tests__/messages-test.js b/packages/jest-message-util/src/__tests__/messages.test.js
similarity index 100%
rename from packages/jest-message-util/src/__tests__/messages-test.js
rename to packages/jest-message-util/src/__tests__/messages.test.js
diff --git a/packages/jest-mock/src/__tests__/jest-mock-test.js b/packages/jest-mock/src/__tests__/jest_mock.test.js
similarity index 100%
rename from packages/jest-mock/src/__tests__/jest-mock-test.js
rename to packages/jest-mock/src/__tests__/jest_mock.test.js
diff --git a/packages/jest-repl/src/__tests__/jest-repl-test.js b/packages/jest-repl/src/__tests__/jest_repl.test.js
similarity index 100%
rename from packages/jest-repl/src/__tests__/jest-repl-test.js
rename to packages/jest-repl/src/__tests__/jest_repl.test.js
diff --git a/packages/jest-resolve-dependencies/src/__tests__/__fixtures__/__snapshots__/related-test.js.snap b/packages/jest-resolve-dependencies/src/__tests__/__fixtures__/__snapshots__/related.test.js.snap
similarity index 100%
rename from packages/jest-resolve-dependencies/src/__tests__/__fixtures__/__snapshots__/related-test.js.snap
rename to packages/jest-resolve-dependencies/src/__tests__/__fixtures__/__snapshots__/related.test.js.snap
diff --git a/packages/jest-resolve-dependencies/src/__tests__/__fixtures__/file-test.js b/packages/jest-resolve-dependencies/src/__tests__/__fixtures__/file.test.js
similarity index 100%
rename from packages/jest-resolve-dependencies/src/__tests__/__fixtures__/file-test.js
rename to packages/jest-resolve-dependencies/src/__tests__/__fixtures__/file.test.js
diff --git a/packages/jest-resolve-dependencies/src/__tests__/__fixtures__/related-test.js b/packages/jest-resolve-dependencies/src/__tests__/__fixtures__/related.test.js
similarity index 100%
rename from packages/jest-resolve-dependencies/src/__tests__/__fixtures__/related-test.js
rename to packages/jest-resolve-dependencies/src/__tests__/__fixtures__/related.test.js
diff --git a/packages/jest-resolve-dependencies/src/__tests__/DependencyResolver-test.js b/packages/jest-resolve-dependencies/src/__tests__/dependency_resolver.test.js
similarity index 89%
rename from packages/jest-resolve-dependencies/src/__tests__/DependencyResolver-test.js
rename to packages/jest-resolve-dependencies/src/__tests__/dependency_resolver.test.js
index 72a34bccca19..692924bff6af 100644
--- a/packages/jest-resolve-dependencies/src/__tests__/DependencyResolver-test.js
+++ b/packages/jest-resolve-dependencies/src/__tests__/dependency_resolver.test.js
@@ -18,7 +18,7 @@ let Runtime;
 let config;
 const cases = {
   fancyCondition: jest.fn(path => path.length > 10),
-  testRegex: jest.fn(path => /-test.js$/.test(path)),
+  testRegex: jest.fn(path => /.test.js$/.test(path)),
 };
 const filter = path => {
   return Object.keys(cases).every(key => cases[key](path));
@@ -73,7 +73,7 @@ test('resolves inverse dependencies for existing path', () => {
   const resolved = dependencyResolver.resolveInverse(paths, filter);
   expect(resolved).toEqual([
     expect.stringContaining(
-      path.join('__tests__', '__fixtures__', 'file-test.js'),
+      path.join('__tests__', '__fixtures__', 'file.test.js'),
     ),
   ]);
 });
@@ -81,16 +81,16 @@ test('resolves inverse dependencies for existing path', () => {
 test('resolves inverse dependencies from available snapshot', () => {
   const paths = new Set([
     path.resolve(__dirname, '__fixtures__/file.js'),
-    path.resolve(__dirname, '__fixtures__/__snapshots__/related-test.js.snap'),
+    path.resolve(__dirname, '__fixtures__/__snapshots__/related.test.js.snap'),
   ]);
   const resolved = dependencyResolver.resolveInverse(paths, filter);
   expect(resolved).toEqual(
     expect.arrayContaining([
       expect.stringContaining(
-        path.join('__tests__', '__fixtures__', 'file-test.js'),
+        path.join('__tests__', '__fixtures__', 'file.test.js'),
       ),
       expect.stringContaining(
-        path.join('__tests__', '__fixtures__', 'related-test.js'),
+        path.join('__tests__', '__fixtures__', 'related.test.js'),
       ),
     ]),
   );
diff --git a/packages/jest-resolve/src/__tests__/resolve-test.js b/packages/jest-resolve/src/__tests__/resolve.test.js
similarity index 100%
rename from packages/jest-resolve/src/__tests__/resolve-test.js
rename to packages/jest-resolve/src/__tests__/resolve.test.js
diff --git a/packages/jest-resolve/src/defaultResolver.js b/packages/jest-resolve/src/default_resolver.js
similarity index 100%
rename from packages/jest-resolve/src/defaultResolver.js
rename to packages/jest-resolve/src/default_resolver.js
diff --git a/packages/jest-resolve/src/index.js b/packages/jest-resolve/src/index.js
index 45d232f1e1bd..0feb1008698d 100644
--- a/packages/jest-resolve/src/index.js
+++ b/packages/jest-resolve/src/index.js
@@ -15,7 +15,7 @@ import fs from 'fs';
 import path from 'path';
 import nodeModulesPaths from 'resolve/lib/node-modules-paths';
 import isBuiltinModule from 'is-builtin-module';
-import defaultResolver from './defaultResolver.js';
+import defaultResolver from './default_resolver.js';
 
 type ResolverConfig = {|
   browser?: boolean,
diff --git a/packages/jest-runtime/src/__mocks__/createRuntime.js b/packages/jest-runtime/src/__mocks__/createRuntime.js
index 5d665afbaa63..bd544fe94a1b 100644
--- a/packages/jest-runtime/src/__mocks__/createRuntime.js
+++ b/packages/jest-runtime/src/__mocks__/createRuntime.js
@@ -17,7 +17,7 @@ module.exports = function createRuntime(filename, config) {
   config = normalize(
     Object.assign(
       {
-        name: 'Runtime-' + filename.replace(/\W/, '-') + '-tests',
+        name: 'Runtime-' + filename.replace(/\W/, '-') + '.tests',
         rootDir: path.resolve(path.dirname(filename), 'test_root'),
       },
       config,
diff --git a/packages/jest-runtime/src/__tests__/__snapshots__/ScriptTransformer-test.js.snap b/packages/jest-runtime/src/__tests__/__snapshots__/script_transformer.test.js.snap
similarity index 100%
rename from packages/jest-runtime/src/__tests__/__snapshots__/ScriptTransformer-test.js.snap
rename to packages/jest-runtime/src/__tests__/__snapshots__/script_transformer.test.js.snap
diff --git a/packages/jest-runtime/src/__tests__/instrumentation-test.js b/packages/jest-runtime/src/__tests__/instrumentation.test.js
similarity index 94%
rename from packages/jest-runtime/src/__tests__/instrumentation-test.js
rename to packages/jest-runtime/src/__tests__/instrumentation.test.js
index f83fe5a8a5da..f779a69b948e 100644
--- a/packages/jest-runtime/src/__tests__/instrumentation-test.js
+++ b/packages/jest-runtime/src/__tests__/instrumentation.test.js
@@ -21,7 +21,7 @@ const FILE_PATH_TO_INSTRUMENT = path.resolve(
 
 it('instruments files', () => {
   const vm = require('vm');
-  const ScriptTransformer = require('../ScriptTransformer');
+  const ScriptTransformer = require('../script_transformer');
   const config = {
     cache: false,
     cacheDirectory: os.tmpdir(),
diff --git a/packages/jest-runtime/src/__tests__/Resolve-browser-test.js b/packages/jest-runtime/src/__tests__/resolve_browser.test.js
similarity index 100%
rename from packages/jest-runtime/src/__tests__/Resolve-browser-test.js
rename to packages/jest-runtime/src/__tests__/resolve_browser.test.js
diff --git a/packages/jest-runtime/src/__tests__/Runtime-cli-test.js b/packages/jest-runtime/src/__tests__/runtime_cli.test.js
similarity index 100%
rename from packages/jest-runtime/src/__tests__/Runtime-cli-test.js
rename to packages/jest-runtime/src/__tests__/runtime_cli.test.js
diff --git a/packages/jest-runtime/src/__tests__/Runtime-environment-test.js b/packages/jest-runtime/src/__tests__/runtime_environment.test.js
similarity index 100%
rename from packages/jest-runtime/src/__tests__/Runtime-environment-test.js
rename to packages/jest-runtime/src/__tests__/runtime_environment.test.js
diff --git a/packages/jest-runtime/src/__tests__/Runtime-genMockFromModule-test.js b/packages/jest-runtime/src/__tests__/runtime_gen_mock_from_module.test.js
similarity index 100%
rename from packages/jest-runtime/src/__tests__/Runtime-genMockFromModule-test.js
rename to packages/jest-runtime/src/__tests__/runtime_gen_mock_from_module.test.js
diff --git a/packages/jest-runtime/src/__tests__/Runtime-internalModule-test.js b/packages/jest-runtime/src/__tests__/runtime_internal_module.test.js
similarity index 100%
rename from packages/jest-runtime/src/__tests__/Runtime-internalModule-test.js
rename to packages/jest-runtime/src/__tests__/runtime_internal_module.test.js
diff --git a/packages/jest-runtime/src/__tests__/Runtime-jest-spyOn-test.js b/packages/jest-runtime/src/__tests__/runtime_jest_spy_on.test.js
similarity index 100%
rename from packages/jest-runtime/src/__tests__/Runtime-jest-spyOn-test.js
rename to packages/jest-runtime/src/__tests__/runtime_jest_spy_on.test.js
diff --git a/packages/jest-runtime/src/__tests__/Runtime-mock-test.js b/packages/jest-runtime/src/__tests__/runtime_mock.test.js
similarity index 100%
rename from packages/jest-runtime/src/__tests__/Runtime-mock-test.js
rename to packages/jest-runtime/src/__tests__/runtime_mock.test.js
diff --git a/packages/jest-runtime/src/__tests__/Runtime-moduleDirectories-test.js b/packages/jest-runtime/src/__tests__/runtime_module_directories.test.js
similarity index 100%
rename from packages/jest-runtime/src/__tests__/Runtime-moduleDirectories-test.js
rename to packages/jest-runtime/src/__tests__/runtime_module_directories.test.js
diff --git a/packages/jest-runtime/src/__tests__/Runtime-NODE_PATH-test.js b/packages/jest-runtime/src/__tests__/runtime_node_path.test.js
similarity index 100%
rename from packages/jest-runtime/src/__tests__/Runtime-NODE_PATH-test.js
rename to packages/jest-runtime/src/__tests__/runtime_node_path.test.js
diff --git a/packages/jest-runtime/src/__tests__/Runtime-requireMock-test.js b/packages/jest-runtime/src/__tests__/runtime_require_mock.test.js
similarity index 100%
rename from packages/jest-runtime/src/__tests__/Runtime-requireMock-test.js
rename to packages/jest-runtime/src/__tests__/runtime_require_mock.test.js
diff --git a/packages/jest-runtime/src/__tests__/Runtime-requireModule-test.js b/packages/jest-runtime/src/__tests__/runtime_require_module.test.js
similarity index 100%
rename from packages/jest-runtime/src/__tests__/Runtime-requireModule-test.js
rename to packages/jest-runtime/src/__tests__/runtime_require_module.test.js
diff --git a/packages/jest-runtime/src/__tests__/Runtime-requireModuleOrMock-test.js b/packages/jest-runtime/src/__tests__/runtime_require_module_or_mock.test.js
similarity index 100%
rename from packages/jest-runtime/src/__tests__/Runtime-requireModuleOrMock-test.js
rename to packages/jest-runtime/src/__tests__/runtime_require_module_or_mock.test.js
diff --git a/packages/jest-runtime/src/__tests__/Runtime-requireModuleOrMock-transitive-deps-test.js b/packages/jest-runtime/src/__tests__/runtime_require_module_or_mock_transitive_deps.test.js
similarity index 100%
rename from packages/jest-runtime/src/__tests__/Runtime-requireModuleOrMock-transitive-deps-test.js
rename to packages/jest-runtime/src/__tests__/runtime_require_module_or_mock_transitive_deps.test.js
diff --git a/packages/jest-runtime/src/__tests__/ScriptTransformer-test.js b/packages/jest-runtime/src/__tests__/script_transformer.test.js
similarity index 99%
rename from packages/jest-runtime/src/__tests__/ScriptTransformer-test.js
rename to packages/jest-runtime/src/__tests__/script_transformer.test.js
index 661f6ea79b11..cc1971409f0e 100644
--- a/packages/jest-runtime/src/__tests__/ScriptTransformer-test.js
+++ b/packages/jest-runtime/src/__tests__/script_transformer.test.js
@@ -153,7 +153,7 @@ describe('ScriptTransformer', () => {
       transformIgnorePatterns: ['/node_modules/'],
     };
 
-    ScriptTransformer = require('../ScriptTransformer');
+    ScriptTransformer = require('../script_transformer');
   };
 
   beforeEach(reset);
diff --git a/packages/jest-runtime/src/index.js b/packages/jest-runtime/src/index.js
index e0024e0100e2..99c04ceb5eeb 100644
--- a/packages/jest-runtime/src/index.js
+++ b/packages/jest-runtime/src/index.js
@@ -23,8 +23,8 @@ import {createDirectory} from 'jest-util';
 import {escapePathForRegex} from 'jest-regex-util';
 import fs from 'graceful-fs';
 import stripBOM from 'strip-bom';
-import ScriptTransformer from './ScriptTransformer';
-import shouldInstrument from './shouldInstrument';
+import ScriptTransformer from './script_transformer';
+import shouldInstrument from './should_instrument';
 import cliArgs from './cli/args';
 
 type Module = {|
diff --git a/packages/jest-runtime/src/ScriptTransformer.js b/packages/jest-runtime/src/script_transformer.js
similarity index 99%
rename from packages/jest-runtime/src/ScriptTransformer.js
rename to packages/jest-runtime/src/script_transformer.js
index 51778164e7e9..221e87b4daa5 100644
--- a/packages/jest-runtime/src/ScriptTransformer.js
+++ b/packages/jest-runtime/src/script_transformer.js
@@ -28,7 +28,7 @@ import {getCacheFilePath} from 'jest-haste-map';
 import stableStringify from 'json-stable-stringify';
 import slash from 'slash';
 import {version as VERSION} from '../package.json';
-import shouldInstrument from './shouldInstrument';
+import shouldInstrument from './should_instrument';
 
 export type Options = {|
   collectCoverage: boolean,
diff --git a/packages/jest-runtime/src/shouldInstrument.js b/packages/jest-runtime/src/should_instrument.js
similarity index 97%
rename from packages/jest-runtime/src/shouldInstrument.js
rename to packages/jest-runtime/src/should_instrument.js
index 102ada2b3f97..1a874e877e77 100644
--- a/packages/jest-runtime/src/shouldInstrument.js
+++ b/packages/jest-runtime/src/should_instrument.js
@@ -9,7 +9,7 @@
  */
 
 import type {Path, ProjectConfig} from 'types/Config';
-import type {Options} from './ScriptTransformer';
+import type {Options} from './script_transformer';
 
 import path from 'path';
 import {escapePathForRegex} from 'jest-regex-util';
diff --git a/packages/jest-snapshot/src/__tests__/matcher-test.js b/packages/jest-snapshot/src/__tests__/matcher.test.js
similarity index 100%
rename from packages/jest-snapshot/src/__tests__/matcher-test.js
rename to packages/jest-snapshot/src/__tests__/matcher.test.js
diff --git a/packages/jest-snapshot/src/__tests__/plugins-test.js b/packages/jest-snapshot/src/__tests__/plugins.test.js
similarity index 100%
rename from packages/jest-snapshot/src/__tests__/plugins-test.js
rename to packages/jest-snapshot/src/__tests__/plugins.test.js
diff --git a/packages/jest-snapshot/src/__tests__/utils-test.js b/packages/jest-snapshot/src/__tests__/utils.test.js
similarity index 98%
rename from packages/jest-snapshot/src/__tests__/utils-test.js
rename to packages/jest-snapshot/src/__tests__/utils.test.js
index bf2d87597885..1251ccd10629 100644
--- a/packages/jest-snapshot/src/__tests__/utils-test.js
+++ b/packages/jest-snapshot/src/__tests__/utils.test.js
@@ -50,8 +50,8 @@ test('testNameToKey', () => {
 });
 
 test('getSnapshotPath()', () => {
-  expect(getSnapshotPath('/abc/cde/a-test.js')).toBe(
-    path.join('/abc', 'cde', '__snapshots__', 'a-test.js.snap'),
+  expect(getSnapshotPath('/abc/cde/a.test.js')).toBe(
+    path.join('/abc', 'cde', '__snapshots__', 'a.test.js.snap'),
   );
 });
 
diff --git a/packages/jest-snapshot/src/index.js b/packages/jest-snapshot/src/index.js
index 15863996e8ef..30021363a678 100644
--- a/packages/jest-snapshot/src/index.js
+++ b/packages/jest-snapshot/src/index.js
@@ -21,7 +21,7 @@ import {
   matcherHint,
   RECEIVED_COLOR,
 } from 'jest-matcher-utils';
-import SnapshotState from './State';
+import SnapshotState from './state';
 import {addSerializer, getSerializers} from './plugins';
 import {SNAPSHOT_EXTENSION} from './utils';
 
diff --git a/packages/jest-snapshot/src/State.js b/packages/jest-snapshot/src/state.js
similarity index 100%
rename from packages/jest-snapshot/src/State.js
rename to packages/jest-snapshot/src/state.js
diff --git a/packages/jest-test-typescript-parser/src/__tests__/TypeScriptParser-test.js b/packages/jest-test-typescript-parser/src/__tests__/type_script_parser.test.js
similarity index 89%
rename from packages/jest-test-typescript-parser/src/__tests__/TypeScriptParser-test.js
rename to packages/jest-test-typescript-parser/src/__tests__/type_script_parser.test.js
index 08bb5762f91c..1cfef59ce3fd 100644
--- a/packages/jest-test-typescript-parser/src/__tests__/TypeScriptParser-test.js
+++ b/packages/jest-test-typescript-parser/src/__tests__/type_script_parser.test.js
@@ -8,7 +8,7 @@
 
 'use strict';
 
-const {parse} = require('../TypeScriptParser');
+const {parse} = require('../type_script_parser');
 const {parserTests} = require('../../../../fixtures/parserTests');
 
 parserTests(parse);
diff --git a/packages/jest-test-typescript-parser/src/index.js b/packages/jest-test-typescript-parser/src/index.js
index b847a586df47..f8b0e729f237 100644
--- a/packages/jest-test-typescript-parser/src/index.js
+++ b/packages/jest-test-typescript-parser/src/index.js
@@ -9,7 +9,7 @@
  */
 
 import {parse as babylonParser, ItBlock, Expect} from 'jest-editor-support';
-import TypeScriptParser from './TypeScriptParser';
+import TypeScriptParser from './type_script_parser';
 
 export type ParserReturn = {
   itBlocks: Array<ItBlock>,
diff --git a/packages/jest-test-typescript-parser/src/TypeScriptParser.js b/packages/jest-test-typescript-parser/src/type_script_parser.js
similarity index 100%
rename from packages/jest-test-typescript-parser/src/TypeScriptParser.js
rename to packages/jest-test-typescript-parser/src/type_script_parser.js
diff --git a/packages/jest-util/src/Console.js b/packages/jest-util/src/Console.js
index b284a753d810..c1e729d8e1e1 100644
--- a/packages/jest-util/src/Console.js
+++ b/packages/jest-util/src/Console.js
@@ -13,7 +13,7 @@ import type {LogType, LogMessage} from 'types/Console';
 
 import {format} from 'util';
 import {Console} from 'console';
-import clearLine from './clearLine';
+import clearLine from './clear_line';
 
 type Formatter = (type: LogType, message: LogMessage) => string;
 
diff --git a/packages/jest-util/src/__tests__/__snapshots__/FakeTimers-test.js.snap b/packages/jest-util/src/__tests__/__snapshots__/fake_timers.test.js.snap
similarity index 100%
rename from packages/jest-util/src/__tests__/__snapshots__/FakeTimers-test.js.snap
rename to packages/jest-util/src/__tests__/__snapshots__/fake_timers.test.js.snap
diff --git a/packages/jest-util/src/__tests__/__snapshots__/validateCLIOptions-test.js.snap b/packages/jest-util/src/__tests__/__snapshots__/validate_cli_options.test.js.snap
similarity index 100%
rename from packages/jest-util/src/__tests__/__snapshots__/validateCLIOptions-test.js.snap
rename to packages/jest-util/src/__tests__/__snapshots__/validate_cli_options.test.js.snap
diff --git a/packages/jest-util/src/__tests__/FakeTimers-test.js b/packages/jest-util/src/__tests__/fake_timers.test.js
similarity index 99%
rename from packages/jest-util/src/__tests__/FakeTimers-test.js
rename to packages/jest-util/src/__tests__/fake_timers.test.js
index 84f6d539f923..210dfac4e556 100644
--- a/packages/jest-util/src/__tests__/FakeTimers-test.js
+++ b/packages/jest-util/src/__tests__/fake_timers.test.js
@@ -15,7 +15,7 @@ describe('FakeTimers', () => {
   let FakeTimers, moduleMocker;
 
   beforeEach(() => {
-    FakeTimers = require('../FakeTimers');
+    FakeTimers = require('../fake_timers');
     const mock = require('jest-mock');
     const global = vm.runInNewContext('this');
     moduleMocker = new mock.ModuleMocker(global);
diff --git a/packages/jest-util/src/__tests__/validateCLIOptions-test.js b/packages/jest-util/src/__tests__/validate_cli_options.test.js
similarity index 94%
rename from packages/jest-util/src/__tests__/validateCLIOptions-test.js
rename to packages/jest-util/src/__tests__/validate_cli_options.test.js
index 30183f8a52f0..a36e01318d49 100644
--- a/packages/jest-util/src/__tests__/validateCLIOptions-test.js
+++ b/packages/jest-util/src/__tests__/validate_cli_options.test.js
@@ -9,7 +9,7 @@
 
 'use strict';
 
-const validateCLIOptions = require('../validateCLIOptions');
+const validateCLIOptions = require('../validate_cli_options');
 
 test('validates yargs special options', () => {
   const options = ['$0', '_', 'help', 'h'];
diff --git a/packages/jest-util/src/clearLine.js b/packages/jest-util/src/clear_line.js
similarity index 100%
rename from packages/jest-util/src/clearLine.js
rename to packages/jest-util/src/clear_line.js
diff --git a/packages/jest-util/src/FakeTimers.js b/packages/jest-util/src/fake_timers.js
similarity index 99%
rename from packages/jest-util/src/FakeTimers.js
rename to packages/jest-util/src/fake_timers.js
index 5c9144bc14a5..b0d47a59daa6 100644
--- a/packages/jest-util/src/FakeTimers.js
+++ b/packages/jest-util/src/fake_timers.js
@@ -13,7 +13,7 @@ import type {Global} from 'types/Global';
 import type {ModuleMocker} from 'jest-mock';
 
 import {formatStackTrace} from 'jest-message-util';
-import setGlobal from './setGlobal';
+import setGlobal from './set_global';
 
 /**
  * We don't know the type of arguments for a callback ahead of time which is why
diff --git a/packages/jest-util/src/formatTestResults.js b/packages/jest-util/src/format_test_results.js
similarity index 100%
rename from packages/jest-util/src/formatTestResults.js
rename to packages/jest-util/src/format_test_results.js
diff --git a/packages/jest-util/src/index.js b/packages/jest-util/src/index.js
index ac3177f2586a..a678191bd70b 100644
--- a/packages/jest-util/src/index.js
+++ b/packages/jest-util/src/index.js
@@ -11,13 +11,13 @@
 import mkdirp from 'mkdirp';
 
 import Console from './Console';
-import FakeTimers from './FakeTimers';
-import NullConsole from './NullConsole';
-import clearLine from './clearLine';
-import formatTestResults from './formatTestResults';
-import installCommonGlobals from './installCommonGlobals';
-import setGlobal from './setGlobal';
-import validateCLIOptions from './validateCLIOptions';
+import FakeTimers from './fake_timers';
+import NullConsole from './null_console';
+import clearLine from './clear_line';
+import formatTestResults from './format_test_results';
+import installCommonGlobals from './install_common_globals';
+import setGlobal from './set_global';
+import validateCLIOptions from './validate_cli_options';
 
 const createDirectory = (path: string) => {
   try {
diff --git a/packages/jest-util/src/installCommonGlobals.js b/packages/jest-util/src/install_common_globals.js
similarity index 100%
rename from packages/jest-util/src/installCommonGlobals.js
rename to packages/jest-util/src/install_common_globals.js
diff --git a/packages/jest-util/src/NullConsole.js b/packages/jest-util/src/null_console.js
similarity index 100%
rename from packages/jest-util/src/NullConsole.js
rename to packages/jest-util/src/null_console.js
diff --git a/packages/jest-util/src/setGlobal.js b/packages/jest-util/src/set_global.js
similarity index 100%
rename from packages/jest-util/src/setGlobal.js
rename to packages/jest-util/src/set_global.js
diff --git a/packages/jest-util/src/validateCLIOptions.js b/packages/jest-util/src/validate_cli_options.js
similarity index 100%
rename from packages/jest-util/src/validateCLIOptions.js
rename to packages/jest-util/src/validate_cli_options.js
diff --git a/packages/jest-validate/src/__tests__/__snapshots__/validate-test.js.snap b/packages/jest-validate/src/__tests__/__snapshots__/validate.test.js.snap
similarity index 100%
rename from packages/jest-validate/src/__tests__/__snapshots__/validate-test.js.snap
rename to packages/jest-validate/src/__tests__/__snapshots__/validate.test.js.snap
diff --git a/packages/jest-validate/src/__tests__/fixtures/jestConfig.js b/packages/jest-validate/src/__tests__/fixtures/jest_config.js
similarity index 100%
rename from packages/jest-validate/src/__tests__/fixtures/jestConfig.js
rename to packages/jest-validate/src/__tests__/fixtures/jest_config.js
diff --git a/packages/jest-validate/src/__tests__/validate-test.js b/packages/jest-validate/src/__tests__/validate.test.js
similarity index 95%
rename from packages/jest-validate/src/__tests__/validate-test.js
rename to packages/jest-validate/src/__tests__/validate.test.js
index c44b17e0da16..da71c398384e 100644
--- a/packages/jest-validate/src/__tests__/validate-test.js
+++ b/packages/jest-validate/src/__tests__/validate.test.js
@@ -10,13 +10,13 @@
 'use strict';
 
 const validate = require('../validate');
-const jestValidateExampleConfig = require('../exampleConfig');
-const jestValidateDefaultConfig = require('../defaultConfig');
+const jestValidateExampleConfig = require('../example_config');
+const jestValidateDefaultConfig = require('../default_config');
 const {
   defaultConfig,
   validConfig,
   deprecatedConfig,
-} = require('./fixtures/jestConfig');
+} = require('./fixtures/jest_config');
 
 test('validates default Jest config', () => {
   expect(
diff --git a/packages/jest-validate/src/defaultConfig.js b/packages/jest-validate/src/default_config.js
similarity index 95%
rename from packages/jest-validate/src/defaultConfig.js
rename to packages/jest-validate/src/default_config.js
index 11a56d9e9dbe..32f16ac13dfe 100644
--- a/packages/jest-validate/src/defaultConfig.js
+++ b/packages/jest-validate/src/default_config.js
@@ -13,7 +13,7 @@ import type {ValidationOptions} from './types';
 import {deprecationWarning} from './deprecated';
 import {unknownOptionWarning} from './warnings';
 import {errorMessage} from './errors';
-import exampleConfig from './exampleConfig';
+import exampleConfig from './example_config';
 import validationCondition from './condition';
 import {ERROR, DEPRECATION, WARNING} from './utils';
 
diff --git a/packages/jest-validate/src/exampleConfig.js b/packages/jest-validate/src/example_config.js
similarity index 100%
rename from packages/jest-validate/src/exampleConfig.js
rename to packages/jest-validate/src/example_config.js
diff --git a/packages/jest-validate/src/validate.js b/packages/jest-validate/src/validate.js
index 3074cd12bb3d..c079ebf94c99 100644
--- a/packages/jest-validate/src/validate.js
+++ b/packages/jest-validate/src/validate.js
@@ -10,7 +10,7 @@
 
 import type {ValidationOptions} from './types';
 
-import defaultConfig from './defaultConfig';
+import defaultConfig from './default_config';
 
 const _validate = (config: Object, options: ValidationOptions) => {
   let hasDeprecationWarnings = false;
diff --git a/packages/pretty-format/perf/test.js b/packages/pretty-format/perf/test.js
index 44ef79c29c0f..0fe159fc0103 100644
--- a/packages/pretty-format/perf/test.js
+++ b/packages/pretty-format/perf/test.js
@@ -13,7 +13,7 @@ import React from 'react';
 import ReactTestRenderer from 'react-test-renderer';
 import leftPad from 'left-pad';
 import prettyFormat from '../build';
-import ReactTestComponent from '../build/plugins/ReactTestComponent';
+import ReactTestComponent from '../build/plugins/react_test_component';
 import worldGeoJson from './world.geo.json';
 
 const NANOSECONDS = 1000000000;
diff --git a/packages/pretty-format/src/__tests__/__snapshots__/React-test.js.snap b/packages/pretty-format/src/__tests__/__snapshots__/react.test.js.snap
similarity index 100%
rename from packages/pretty-format/src/__tests__/__snapshots__/React-test.js.snap
rename to packages/pretty-format/src/__tests__/__snapshots__/react.test.js.snap
diff --git a/packages/pretty-format/src/__tests__/AsymmetricMatcher-test.js b/packages/pretty-format/src/__tests__/asymmetric_matcher.test.js
similarity index 98%
rename from packages/pretty-format/src/__tests__/AsymmetricMatcher-test.js
rename to packages/pretty-format/src/__tests__/asymmetric_matcher.test.js
index 0749fcb14bd9..692a3ef2dd3f 100644
--- a/packages/pretty-format/src/__tests__/AsymmetricMatcher-test.js
+++ b/packages/pretty-format/src/__tests__/asymmetric_matcher.test.js
@@ -7,7 +7,7 @@
  */
 
 const prettyFormat = require('../');
-const AsymmetricMatcher = require('../plugins/AsymmetricMatcher');
+const AsymmetricMatcher = require('../plugins/asymmetric_matcher');
 let options;
 
 function fnNameFor(func) {
diff --git a/packages/pretty-format/src/__tests__/ConvertAnsi-test.js b/packages/pretty-format/src/__tests__/convert_ansi.test.js
similarity index 96%
rename from packages/pretty-format/src/__tests__/ConvertAnsi-test.js
rename to packages/pretty-format/src/__tests__/convert_ansi.test.js
index 184c4ca3fc1d..1de0d13750a8 100644
--- a/packages/pretty-format/src/__tests__/ConvertAnsi-test.js
+++ b/packages/pretty-format/src/__tests__/convert_ansi.test.js
@@ -8,7 +8,7 @@
 
 const ansiStyle = require('ansi-styles');
 const prettyFormat = require('../');
-const ConvertAnsiPlugin = require('../plugins/ConvertAnsi');
+const ConvertAnsiPlugin = require('../plugins/convert_ansi');
 
 const prettyFormatResult = (val: string) => {
   return prettyFormat(val, {
diff --git a/packages/pretty-format/src/__tests__/HTMLElement-test.js b/packages/pretty-format/src/__tests__/html_element.test.js
similarity index 98%
rename from packages/pretty-format/src/__tests__/HTMLElement-test.js
rename to packages/pretty-format/src/__tests__/html_element.test.js
index 359b63fe9b34..f03c44eaa95d 100644
--- a/packages/pretty-format/src/__tests__/HTMLElement-test.js
+++ b/packages/pretty-format/src/__tests__/html_element.test.js
@@ -11,7 +11,7 @@
 
 'use strict';
 
-const HTMLElementPlugin = require('../plugins/HTMLElement');
+const HTMLElementPlugin = require('../plugins/html_element');
 const toPrettyPrintTo = require('./expect-util').getPrettyPrint([
   HTMLElementPlugin,
 ]);
diff --git a/packages/pretty-format/src/__tests__/Immutable-test.js b/packages/pretty-format/src/__tests__/immutable.test.js
similarity index 98%
rename from packages/pretty-format/src/__tests__/Immutable-test.js
rename to packages/pretty-format/src/__tests__/immutable.test.js
index 0820c505f978..64b540627982 100644
--- a/packages/pretty-format/src/__tests__/Immutable-test.js
+++ b/packages/pretty-format/src/__tests__/immutable.test.js
@@ -10,9 +10,9 @@
 
 const React = require('react');
 const Immutable = require('immutable');
-const ReactElementPlugin = require('../plugins/ReactElement');
-const ReactTestComponentPlugin = require('../plugins/ReactTestComponent');
-const ImmutablePlugins = require('../plugins/ImmutablePlugins');
+const ReactElementPlugin = require('../plugins/react_element');
+const ReactTestComponentPlugin = require('../plugins/react_test_component');
+const ImmutablePlugins = require('../plugins/immutable_plugins');
 const toPrettyPrintTo = require('./expect-util').getPrettyPrint(
   [ReactElementPlugin, ReactTestComponentPlugin].concat(ImmutablePlugins),
 );
diff --git a/packages/pretty-format/src/__tests__/pretty-format-test.js b/packages/pretty-format/src/__tests__/pretty_format.test.js
similarity index 100%
rename from packages/pretty-format/src/__tests__/pretty-format-test.js
rename to packages/pretty-format/src/__tests__/pretty_format.test.js
diff --git a/packages/pretty-format/src/__tests__/React-test.js b/packages/pretty-format/src/__tests__/react.test.js
similarity index 98%
rename from packages/pretty-format/src/__tests__/React-test.js
rename to packages/pretty-format/src/__tests__/react.test.js
index 560428e459f5..871ccb7f0f15 100644
--- a/packages/pretty-format/src/__tests__/React-test.js
+++ b/packages/pretty-format/src/__tests__/react.test.js
@@ -10,8 +10,8 @@ const React = require('react');
 const renderer = require('react-test-renderer');
 
 const prettyFormat = require('../');
-const ReactTestComponent = require('../plugins/ReactTestComponent');
-const ReactElement = require('../plugins/ReactElement');
+const ReactTestComponent = require('../plugins/react_test_component');
+const ReactElement = require('../plugins/react_element');
 
 function assertPrintedJSX(actual, expected, opts) {
   expect(
diff --git a/packages/pretty-format/src/index.js b/packages/pretty-format/src/index.js
index 5f6e04c2c608..1baab04fe05b 100644
--- a/packages/pretty-format/src/index.js
+++ b/packages/pretty-format/src/index.js
@@ -18,12 +18,12 @@ import type {
 
 import style from 'ansi-styles';
 
-import AsymmetricMatcher from './plugins/AsymmetricMatcher';
-import ConvertAnsi from './plugins/ConvertAnsi';
-import HTMLElement from './plugins/HTMLElement';
-import Immutable from './plugins/ImmutablePlugins';
-import ReactElement from './plugins/ReactElement';
-import ReactTestComponent from './plugins/ReactTestComponent';
+import AsymmetricMatcher from './plugins/asymmetric_matcher';
+import ConvertAnsi from './plugins/convert_ansi';
+import HTMLElement from './plugins/html_element';
+import Immutable from './plugins/immutable_plugins';
+import ReactElement from './plugins/react_element';
+import ReactTestComponent from './plugins/react_test_component';
 
 type Theme = {|
   comment?: string,
diff --git a/packages/pretty-format/src/plugins/AsymmetricMatcher.js b/packages/pretty-format/src/plugins/asymmetric_matcher.js
similarity index 100%
rename from packages/pretty-format/src/plugins/AsymmetricMatcher.js
rename to packages/pretty-format/src/plugins/asymmetric_matcher.js
diff --git a/packages/pretty-format/src/plugins/ConvertAnsi.js b/packages/pretty-format/src/plugins/convert_ansi.js
similarity index 100%
rename from packages/pretty-format/src/plugins/ConvertAnsi.js
rename to packages/pretty-format/src/plugins/convert_ansi.js
diff --git a/packages/pretty-format/src/plugins/HTMLElement.js b/packages/pretty-format/src/plugins/html_element.js
similarity index 98%
rename from packages/pretty-format/src/plugins/HTMLElement.js
rename to packages/pretty-format/src/plugins/html_element.js
index a30fb88f4c35..d840effdc668 100644
--- a/packages/pretty-format/src/plugins/HTMLElement.js
+++ b/packages/pretty-format/src/plugins/html_element.js
@@ -10,7 +10,7 @@
 
 import type {Colors, Indent, Options, Print, Plugin} from 'types/PrettyFormat';
 
-import escapeHTML from './lib/escapeHTML';
+import escapeHTML from './lib/escape_html';
 
 type Attribute = {
   name: string,
diff --git a/packages/pretty-format/src/plugins/ImmutableList.js b/packages/pretty-format/src/plugins/immutable_list.js
similarity index 93%
rename from packages/pretty-format/src/plugins/ImmutableList.js
rename to packages/pretty-format/src/plugins/immutable_list.js
index a9a957d415ba..0c02d164252b 100644
--- a/packages/pretty-format/src/plugins/ImmutableList.js
+++ b/packages/pretty-format/src/plugins/immutable_list.js
@@ -10,7 +10,7 @@
 
 import type {Colors, Indent, Options, Print, Plugin} from 'types/PrettyFormat';
 
-import printImmutable from './lib/printImmutable';
+import printImmutable from './lib/print_immutable';
 
 const IS_LIST = '@@__IMMUTABLE_LIST__@@';
 const test = (maybeList: any) => !!(maybeList && maybeList[IS_LIST]);
diff --git a/packages/pretty-format/src/plugins/ImmutableMap.js b/packages/pretty-format/src/plugins/immutable_map.js
similarity index 93%
rename from packages/pretty-format/src/plugins/ImmutableMap.js
rename to packages/pretty-format/src/plugins/immutable_map.js
index e311985aada8..f66aaa2cf145 100644
--- a/packages/pretty-format/src/plugins/ImmutableMap.js
+++ b/packages/pretty-format/src/plugins/immutable_map.js
@@ -10,7 +10,7 @@
 
 import type {Colors, Indent, Options, Print, Plugin} from 'types/PrettyFormat';
 
-import printImmutable from './lib/printImmutable';
+import printImmutable from './lib/print_immutable';
 
 const IS_MAP = '@@__IMMUTABLE_MAP__@@';
 const IS_ORDERED = '@@__IMMUTABLE_ORDERED__@@';
diff --git a/packages/pretty-format/src/plugins/ImmutableOrderedMap.js b/packages/pretty-format/src/plugins/immutable_ordered_map.js
similarity index 94%
rename from packages/pretty-format/src/plugins/ImmutableOrderedMap.js
rename to packages/pretty-format/src/plugins/immutable_ordered_map.js
index c51199ed2882..ded415e2c650 100644
--- a/packages/pretty-format/src/plugins/ImmutableOrderedMap.js
+++ b/packages/pretty-format/src/plugins/immutable_ordered_map.js
@@ -10,7 +10,7 @@
 
 import type {Colors, Indent, Options, Print, Plugin} from 'types/PrettyFormat';
 
-import printImmutable from './lib/printImmutable';
+import printImmutable from './lib/print_immutable';
 
 const IS_MAP = '@@__IMMUTABLE_MAP__@@';
 const IS_ORDERED = '@@__IMMUTABLE_ORDERED__@@';
diff --git a/packages/pretty-format/src/plugins/ImmutableOrderedSet.js b/packages/pretty-format/src/plugins/immutable_ordered_set.js
similarity index 94%
rename from packages/pretty-format/src/plugins/ImmutableOrderedSet.js
rename to packages/pretty-format/src/plugins/immutable_ordered_set.js
index 88763fd78866..e43dbe5d570e 100644
--- a/packages/pretty-format/src/plugins/ImmutableOrderedSet.js
+++ b/packages/pretty-format/src/plugins/immutable_ordered_set.js
@@ -10,7 +10,7 @@
 
 import type {Colors, Indent, Options, Print, Plugin} from 'types/PrettyFormat';
 
-import printImmutable from './lib/printImmutable';
+import printImmutable from './lib/print_immutable';
 
 const IS_SET = '@@__IMMUTABLE_SET__@@';
 const IS_ORDERED = '@@__IMMUTABLE_ORDERED__@@';
diff --git a/packages/pretty-format/src/plugins/ImmutablePlugins.js b/packages/pretty-format/src/plugins/immutable_plugins.js
similarity index 57%
rename from packages/pretty-format/src/plugins/ImmutablePlugins.js
rename to packages/pretty-format/src/plugins/immutable_plugins.js
index 1ad73ce2839b..cd614fffef8d 100644
--- a/packages/pretty-format/src/plugins/ImmutablePlugins.js
+++ b/packages/pretty-format/src/plugins/immutable_plugins.js
@@ -8,13 +8,13 @@
  * @flow
  */
 
-import ImmutableList from './ImmutableList';
-import ImmutableSet from './ImmutableSet';
-import ImmutableMap from './ImmutableMap';
-import ImmutableStack from './ImmutableStack';
-import ImmutableOrderedSet from './ImmutableOrderedSet';
-import ImmutableOrderedMap from './ImmutableOrderedMap';
-import ImmutableRecord from './ImmutableRecord';
+import ImmutableList from './immutable_list';
+import ImmutableSet from './immutable_set';
+import ImmutableMap from './immutable_map';
+import ImmutableStack from './immutable_stack';
+import ImmutableOrderedSet from './immutable_ordered_set';
+import ImmutableOrderedMap from './immutable_ordered_map';
+import ImmutableRecord from './immutable_record';
 
 module.exports = [
   ImmutableList,
diff --git a/packages/pretty-format/src/plugins/ImmutableRecord.js b/packages/pretty-format/src/plugins/immutable_record.js
similarity index 93%
rename from packages/pretty-format/src/plugins/ImmutableRecord.js
rename to packages/pretty-format/src/plugins/immutable_record.js
index 1b8656b9ae76..7b25f21519db 100644
--- a/packages/pretty-format/src/plugins/ImmutableRecord.js
+++ b/packages/pretty-format/src/plugins/immutable_record.js
@@ -10,7 +10,7 @@
 
 import type {Colors, Indent, Options, Print, Plugin} from 'types/PrettyFormat';
 
-import printImmutable from './lib/printImmutable';
+import printImmutable from './lib/print_immutable';
 
 const IS_RECORD = '@@__IMMUTABLE_RECORD__@@';
 const test = (maybeRecord: any) => !!(maybeRecord && maybeRecord[IS_RECORD]);
diff --git a/packages/pretty-format/src/plugins/ImmutableSet.js b/packages/pretty-format/src/plugins/immutable_set.js
similarity index 93%
rename from packages/pretty-format/src/plugins/ImmutableSet.js
rename to packages/pretty-format/src/plugins/immutable_set.js
index 74005a69c471..57ce45db5a5e 100644
--- a/packages/pretty-format/src/plugins/ImmutableSet.js
+++ b/packages/pretty-format/src/plugins/immutable_set.js
@@ -10,7 +10,7 @@
 
 import type {Colors, Indent, Options, Print, Plugin} from 'types/PrettyFormat';
 
-import printImmutable from './lib/printImmutable';
+import printImmutable from './lib/print_immutable';
 
 const IS_SET = '@@__IMMUTABLE_SET__@@';
 const IS_ORDERED = '@@__IMMUTABLE_ORDERED__@@';
diff --git a/packages/pretty-format/src/plugins/ImmutableStack.js b/packages/pretty-format/src/plugins/immutable_stack.js
similarity index 93%
rename from packages/pretty-format/src/plugins/ImmutableStack.js
rename to packages/pretty-format/src/plugins/immutable_stack.js
index 110400e8a996..75a22ce6160e 100644
--- a/packages/pretty-format/src/plugins/ImmutableStack.js
+++ b/packages/pretty-format/src/plugins/immutable_stack.js
@@ -10,7 +10,7 @@
 
 import type {Colors, Indent, Options, Print, Plugin} from 'types/PrettyFormat';
 
-import printImmutable from './lib/printImmutable';
+import printImmutable from './lib/print_immutable';
 
 const IS_STACK = '@@__IMMUTABLE_STACK__@@';
 const test = (maybeStack: any) => !!(maybeStack && maybeStack[IS_STACK]);
diff --git a/packages/pretty-format/src/plugins/lib/escapeHTML.js b/packages/pretty-format/src/plugins/lib/escape_html.js
similarity index 100%
rename from packages/pretty-format/src/plugins/lib/escapeHTML.js
rename to packages/pretty-format/src/plugins/lib/escape_html.js
diff --git a/packages/pretty-format/src/plugins/lib/printImmutable.js b/packages/pretty-format/src/plugins/lib/print_immutable.js
similarity index 100%
rename from packages/pretty-format/src/plugins/lib/printImmutable.js
rename to packages/pretty-format/src/plugins/lib/print_immutable.js
diff --git a/packages/pretty-format/src/plugins/ReactElement.js b/packages/pretty-format/src/plugins/react_element.js
similarity index 98%
rename from packages/pretty-format/src/plugins/ReactElement.js
rename to packages/pretty-format/src/plugins/react_element.js
index 899e46e9824f..af996313a010 100644
--- a/packages/pretty-format/src/plugins/ReactElement.js
+++ b/packages/pretty-format/src/plugins/react_element.js
@@ -10,7 +10,7 @@
 
 import type {Colors, Indent, Options, Print, Plugin} from 'types/PrettyFormat';
 
-import escapeHTML from './lib/escapeHTML';
+import escapeHTML from './lib/escape_html';
 
 const reactElement = Symbol.for('react.element');
 
diff --git a/packages/pretty-format/src/plugins/ReactTestComponent.js b/packages/pretty-format/src/plugins/react_test_component.js
similarity index 98%
rename from packages/pretty-format/src/plugins/ReactTestComponent.js
rename to packages/pretty-format/src/plugins/react_test_component.js
index 97ca3be3d53e..72d37449e619 100644
--- a/packages/pretty-format/src/plugins/ReactTestComponent.js
+++ b/packages/pretty-format/src/plugins/react_test_component.js
@@ -18,7 +18,7 @@ import type {
   ReactTestChild,
 } from 'types/PrettyFormat';
 
-import escapeHTML from './lib/escapeHTML';
+import escapeHTML from './lib/escape_html';
 
 const reactTestInstance = Symbol.for('react.test.json');