feat(rules): add no-commented-out rule (#262)

README.md

@@ -96,6 +96,7 @@ for more information about extending configuration files.
 | [lowercase-name][]           | Disallow capitalized test names                                   |                  | ![fixable-green][]  |
 | [no-alias-methods][]         | Disallow alias methods                                            | ![recommended][] | ![fixable-green][]  |
 | [no-disabled-tests][]        | Disallow disabled tests                                           | ![recommended][] |                     |
+| [no-commented-out-tests][]   | Disallow commented out tests                                      |                  |                     |
 | [no-empty-title][]           | Disallow empty titles                                             |                  |                     |
 | [no-focused-tests][]         | Disallow focused tests                                            | ![recommended][] |                     |
 | [no-hooks][]                 | Disallow setup and teardown hooks                                 |                  |                     |
@@ -142,6 +143,7 @@ https://github.com/dangreenisrael/eslint-plugin-jest-formatting
 [lowercase-name]: docs/rules/lowercase-name.md
 [no-alias-methods]: docs/rules/no-alias-methods.md
 [no-disabled-tests]: docs/rules/no-disabled-tests.md
+[no-commented-out-tests]: docs/rules/no-commented-out-tests.md
 [no-empty-title]: docs/rules/no-empty-title.md
 [no-focused-tests]: docs/rules/no-focused-tests.md
 [no-hooks]: docs/rules/no-hooks.md

docs/rules/no-commented-out-tests.md

@@ -0,0 +1,61 @@
+# Disallow commented out tests (no-commented-out-tests)
+
+This rule raises a warning about commented out tests. It's similar to
+no-disabled-tests rule.
+
+## Rule Details
+
+The rule uses fuzzy matching to do its best to determine what constitutes a
+commented out test, checking for a presence of `it(`, `describe(`, `it.skip(`,
+etc. in code comments.
+
+The following patterns are considered warnings:
+
+```js
+// describe('foo', () => {});
+// it('foo', () => {});
+// test('foo', () => {});
+
+// describe.skip('foo', () => {});
+// it.skip('foo', () => {});
+// test.skip('foo', () => {});
+
+// describe['skip']('bar', () => {});
+// it['skip']('bar', () => {});
+// test['skip']('bar', () => {});
+
+// xdescribe('foo', () => {});
+// xit('foo', () => {});
+// xtest('foo', () => {});
+
+/*
+describe('foo', () => {});
+*/
+```
+
+These patterns would not be considered warnings:
+
+```js
+describe('foo', () => {});
+it('foo', () => {});
+test('foo', () => {});
+
+describe.only('bar', () => {});
+it.only('bar', () => {});
+test.only('bar', () => {});
+
+// foo('bar', () => {});
+```
+
+### Limitations
+
+The plugin looks at the literal function names within test code, so will not
+catch more complex examples of commented out tests, such as:
+
+```js
+// const testSkip = test.skip;
+// testSkip('skipped test', () => {});
+
+// const myTest = test;
+// myTest('does not have function body');
+```

src/__tests__/rules.test.js

@@ -5,7 +5,7 @@ const path = require('path');
 const { rules } = require('../');
 
 const ruleNames = Object.keys(rules);
-const numberOfRules = 31;
+const numberOfRules = 32;
 
 describe('rules', () => {
   it('should have a corresponding doc for each rule', () => {

src/rules/__tests__/no-commented-out-tests.test.js

@@ -0,0 +1,215 @@
+'use strict';
+
+const { RuleTester } = require('eslint');
+const rule = require('../no-commented-out-tests');
+
+const ruleTester = new RuleTester({
+  parserOptions: {
+    sourceType: 'module',
+  },
+});
+
+ruleTester.run('no-commented-out-tests', rule, {
+  valid: [
+    '// foo("bar", function () {})',
+    'describe("foo", function () {})',
+    'it("foo", function () {})',
+    'describe.only("foo", function () {})',
+    'it.only("foo", function () {})',
+    'test("foo", function () {})',
+    'test.only("foo", function () {})',
+    'var appliedSkip = describe.skip; appliedSkip.apply(describe)',
+    'var calledSkip = it.skip; calledSkip.call(it)',
+    '({ f: function () {} }).f()',
+    '(a || b).f()',
+    'itHappensToStartWithIt()',
+    'testSomething()',
+    [
+      'import { pending } from "actions"',
+      '',
+      'test("foo", () => {',
+      '  expect(pending()).toEqual({})',
+      '})',
+    ].join('\n'),
+    [
+      'const { pending } = require("actions")',
+      '',
+      'test("foo", () => {',
+      '  expect(pending()).toEqual({})',
+      '})',
+    ].join('\n'),
+    [
+      'test("foo", () => {',
+      '  const pending = getPending()',
+      '  expect(pending()).toEqual({})',
+      '})',
+    ].join('\n'),
+    [
+      'test("foo", () => {',
+      '  expect(pending()).toEqual({})',
+      '})',
+      '',
+      'function pending() {',
+      '  return {}',
+      '}',
+    ].join('\n'),
+  ],
+
+  invalid: [
+    {
+      code: '// describe("foo", function () {})',
+      errors: [
+        { message: 'Some tests seem to be commented', column: 1, line: 1 },
+      ],
+    },
+    {
+      code: '// describe["skip"]("foo", function () {})',
+      errors: [
+        { message: 'Some tests seem to be commented', column: 1, line: 1 },
+      ],
+    },
+    {
+      code: '// describe[\'skip\']("foo", function () {})',
+      errors: [
+        { message: 'Some tests seem to be commented', column: 1, line: 1 },
+      ],
+    },
+    {
+      code: '// it.skip("foo", function () {})',
+      errors: [
+        { message: 'Some tests seem to be commented', column: 1, line: 1 },
+      ],
+    },
+    {
+      code: '// it.only("foo", function () {})',
+      errors: [
+        { message: 'Some tests seem to be commented', column: 1, line: 1 },
+      ],
+    },
+    {
+      code: '// it["skip"]("foo", function () {})',
+      errors: [
+        { message: 'Some tests seem to be commented', column: 1, line: 1 },
+      ],
+    },
+    {
+      code: '// test.skip("foo", function () {})',
+      errors: [
+        { message: 'Some tests seem to be commented', column: 1, line: 1 },
+      ],
+    },
+    {
+      code: '// test["skip"]("foo", function () {})',
+      errors: [
+        { message: 'Some tests seem to be commented', column: 1, line: 1 },
+      ],
+    },
+    {
+      code: '// xdescribe("foo", function () {})',
+      errors: [
+        { message: 'Some tests seem to be commented', column: 1, line: 1 },
+      ],
+    },
+    {
+      code: '// xit("foo", function () {})',
+      errors: [
+        { message: 'Some tests seem to be commented', column: 1, line: 1 },
+      ],
+    },
+    {
+      code: '// fit("foo", function () {})',
+      errors: [
+        { message: 'Some tests seem to be commented', column: 1, line: 1 },
+      ],
+    },
+    {
+      code: '// xtest("foo", function () {})',
+      errors: [
+        { message: 'Some tests seem to be commented', column: 1, line: 1 },
+      ],
+    },
+    {
+      code: `// test(
+             //   "foo", function () {}
+             // )`,
+      errors: [
+        { message: 'Some tests seem to be commented', column: 1, line: 1 },
+      ],
+    },
+    {
+      code: `/* test
+              (
+                "foo", function () {}
+              )
+              */`,
+      errors: [
+        { message: 'Some tests seem to be commented', column: 1, line: 1 },
+      ],
+    },
+    {
+      code: '// it("has title but no callback")',
+      errors: [
+        {
+          message: 'Some tests seem to be commented',
+          column: 1,
+          line: 1,
+        },
+      ],
+    },
+    {
+      code: '// it()',
+      errors: [
+        {
+          message: 'Some tests seem to be commented',
+          column: 1,
+          line: 1,
+        },
+      ],
+    },
+    {
+      code: '// test.someNewMethodThatMightBeAddedInTheFuture()',
+      errors: [
+        {
+          message: 'Some tests seem to be commented',
+          column: 1,
+          line: 1,
+        },
+      ],
+    },
+    {
+      code: '// test["someNewMethodThatMightBeAddedInTheFuture"]()',
+      errors: [
+        {
+          message: 'Some tests seem to be commented',
+          column: 1,
+          line: 1,
+        },
+      ],
+    },
+    {
+      code: '// test("has title but no callback")',
+      errors: [
+        {
+          message: 'Some tests seem to be commented',
+          column: 1,
+          line: 1,
+        },
+      ],
+    },
+    {
+      code: `
+      foo()
+      /* 
+      describe("has title but no callback", () => {}) 
+      */
+      bar()`,
+      errors: [
+        {
+          message: 'Some tests seem to be commented',
+          column: 7,
+          line: 3,
+        },
+      ],
+    },
+  ],
+});

src/rules/no-commented-out-tests.js

@@ -0,0 +1,39 @@
+'use strict';
+
+const { getDocsUrl } = require('./util');
+
+const message = 'Some tests seem to be commented';
+
+function hasTests(node) {
+  return /(x|f)?(test|it|describe)(\.\w+|\[['"]\w+['"]\])?\s*\(/m.test(
+    node.value,
+  );
+}
+
+module.exports = {
+  meta: {
+    docs: {
+      url: getDocsUrl(__filename),
+    },
+  },
+  create(context) {
+    const sourceCode = context.getSourceCode();
+
+    function checkNode(node) {
+      if (!hasTests(node)) return;
+
+      context.report({
+        message,
+        node,
+      });
+    }
+
+    return {
+      Program() {
+        const comments = sourceCode.getAllComments();
+
+        comments.filter(token => token.type !== 'Shebang').forEach(checkNode);
+      },
+    };
+  },
+};