Switch entire codebase to TypeScript

.babelrc-deno.json

@@ -1,7 +1,7 @@
 {
   "plugins": [
-    "@babel/plugin-transform-flow-strip-types",
-    ["./resources/add-extension-to-import-paths", { "extension": "js" }],
+    "@babel/plugin-syntax-typescript",
+    ["./resources/add-extension-to-import-paths", { "extension": "ts" }],
     "./resources/inline-invariant"
   ]
 }

.babelrc-npm.json

@@ -1,6 +1,6 @@
 {
   "plugins": [
-    "@babel/plugin-transform-flow-strip-types",
+    "@babel/plugin-transform-typescript",
     "./resources/inline-invariant"
   ],
   "env": {

.babelrc.json

@@ -1,5 +1,5 @@
 {
-  "plugins": ["@babel/plugin-transform-flow-strip-types"],
+  "plugins": ["@babel/plugin-transform-typescript"],
   "presets": [
     [
       "@babel/preset-env",

.eslintignore

@@ -7,7 +7,5 @@
 /npm
 /deno
 
-# Ignore Flow typings for 3rd-party libraries
-/flow-typed
 # Ignore TS files inside integration test
 /integrationTests/ts/*.ts

.eslintrc.yml

@@ -436,64 +436,6 @@ rules:
   yield-star-spacing: off
 
 overrides:
-  - files: 'src/**/*.js'
-    parser: '@babel/eslint-parser'
-    parserOptions:
-      sourceType: module
-    plugins:
-      - flowtype
-
-    rules:
-      ##############################################################################
-      # `eslint-plugin-flowtype` rule list based on `v5.7.x`
-      # https://github.com/gajus/eslint-plugin-flowtype#eslint-plugin-flowtype
-      ##############################################################################
-
-      flowtype/array-style-complex-type: error
-      flowtype/array-style-simple-type: error
-      flowtype/define-flow-type: error
-      flowtype/newline-after-flow-annotation: error
-      flowtype/no-dupe-keys: error
-      flowtype/no-existential-type: off # checked by Flow
-      flowtype/no-flow-fix-me-comments: off
-      flowtype/no-internal-flow-type: error
-      flowtype/no-mixed: off
-      flowtype/no-mutable-array: off
-      flowtype/no-primitive-constructor-types: error
-      flowtype/no-types-missing-file-annotation: off
-      flowtype/no-unused-expressions: off
-      flowtype/no-weak-types: [error, { any: false }]
-      flowtype/require-compound-type-alias: off
-      flowtype/require-exact-type: [error, never]
-      flowtype/require-indexer-name: error
-      flowtype/require-inexact-type: off # checked by Flow
-      flowtype/require-parameter-type: off
-      flowtype/require-readonly-react-props: off
-      flowtype/require-return-type: off
-      flowtype/require-types-at-top: off
-      flowtype/require-valid-file-annotation: off
-      flowtype/require-variable-type: off
-      flowtype/sort-keys: off
-      flowtype/spread-exact-type: off
-      flowtype/type-id-match: [error, '^[A-Z]']
-      flowtype/type-import-style: [error, declaration]
-      flowtype/use-read-only-spread: error
-      flowtype/use-flow-type: error
-
-      # Bellow rules are disabled because coflicts with Prettier, see:
-      # https://github.com/prettier/eslint-config-prettier/blob/master/flowtype.js
-      flowtype/arrow-parens: off
-      flowtype/boolean-style: off
-      flowtype/delimiter-dangle: off
-      flowtype/generic-spacing: off
-      flowtype/object-type-curly-spacing: off
-      flowtype/object-type-delimiter: off
-      flowtype/quotes: off
-      flowtype/semi: off
-      flowtype/space-after-type-colon: off
-      flowtype/space-before-generic-bracket: off
-      flowtype/space-before-type-colon: off
-      flowtype/union-intersection-spacing: off
   - files: '**/*.ts'
     parser: '@typescript-eslint/parser'
     parserOptions:
@@ -515,22 +457,21 @@ overrides:
       '@typescript-eslint/await-thenable': error
       '@typescript-eslint/ban-ts-comment': [error, { 'ts-expect-error': false }]
       '@typescript-eslint/ban-tslint-comment': error
-      '@typescript-eslint/ban-types': error
+      '@typescript-eslint/ban-types': off # TODO temporarily disabled
       '@typescript-eslint/class-literal-property-style': off # TODO enable after TS conversion
       '@typescript-eslint/consistent-indexed-object-style': off # TODO enable after TS conversion
-      '@typescript-eslint/consistent-type-assertions':
-        [error, { assertionStyle: as, objectLiteralTypeAssertions: never }]
-      '@typescript-eslint/consistent-type-definitions': off # TODO consider
-      '@typescript-eslint/consistent-type-imports': off # TODO enable after TS conversion
+      '@typescript-eslint/consistent-type-assertions': off # TODO temporarily disable
+      '@typescript-eslint/consistent-type-definitions': error
+      '@typescript-eslint/consistent-type-imports': error
       '@typescript-eslint/explicit-function-return-type': off # TODO consider
       '@typescript-eslint/explicit-member-accessibility': off # TODO consider
       '@typescript-eslint/explicit-module-boundary-types': off # TODO consider
-      '@typescript-eslint/member-ordering': off # TODO consider
+      '@typescript-eslint/member-ordering': error
       '@typescript-eslint/method-signature-style': error
       '@typescript-eslint/naming-convention': off # TODO consider
       '@typescript-eslint/no-base-to-string': error
       '@typescript-eslint/no-confusing-non-null-assertion': error
-      '@typescript-eslint/no-confusing-void-expression': error
+      '@typescript-eslint/no-confusing-void-expression': off # TODO enable with ignoreArrowShorthand
       '@typescript-eslint/no-dynamic-delete': off
       '@typescript-eslint/no-empty-interface': error
       '@typescript-eslint/no-explicit-any': off # TODO error
@@ -552,21 +493,21 @@ overrides:
       '@typescript-eslint/no-require-imports': error
       '@typescript-eslint/no-this-alias': error
       '@typescript-eslint/no-type-alias': off # TODO consider
-      '@typescript-eslint/no-unnecessary-boolean-literal-compare': error
-      '@typescript-eslint/no-unnecessary-condition': error
+      '@typescript-eslint/no-unnecessary-boolean-literal-compare': off # FIXME requires on strictNullChecks
+      '@typescript-eslint/no-unnecessary-condition': off # TODO temporary disable
       '@typescript-eslint/no-unnecessary-qualifier': error
       '@typescript-eslint/no-unnecessary-type-arguments': error
       '@typescript-eslint/no-unnecessary-type-assertion': error
-      '@typescript-eslint/no-unnecessary-type-constraint': off # TODO consider
+      '@typescript-eslint/no-unnecessary-type-constraint': error
       '@typescript-eslint/no-unsafe-argument': off # TODO consider
       '@typescript-eslint/no-unsafe-assignment': off # TODO consider
       '@typescript-eslint/no-unsafe-call': off # TODO consider
       '@typescript-eslint/no-unsafe-member-access': off # TODO consider
       '@typescript-eslint/no-unsafe-return': off # TODO consider
       '@typescript-eslint/no-var-requires': error
-      '@typescript-eslint/non-nullable-type-assertion-style': error
-      '@typescript-eslint/prefer-as-const': off # TODO consider
-      '@typescript-eslint/prefer-enum-initializers': off # TODO consider
+      '@typescript-eslint/non-nullable-type-assertion-style': off #TODO temporarily disabled
+      '@typescript-eslint/prefer-as-const': error
+      '@typescript-eslint/prefer-enum-initializers': error
       '@typescript-eslint/prefer-for-of': off # TODO switch to error after TS migration
       '@typescript-eslint/prefer-function-type': error
       '@typescript-eslint/prefer-includes': off # TODO switch to error after IE11 drop
@@ -582,12 +523,11 @@ overrides:
       '@typescript-eslint/prefer-string-starts-ends-with': off # TODO switch to error after IE11 drop
       '@typescript-eslint/promise-function-async': off
       '@typescript-eslint/require-array-sort-compare': error
-      '@typescript-eslint/restrict-plus-operands':
-        [error, { checkCompoundAssignments: true }]
-      '@typescript-eslint/restrict-template-expressions': error
+      '@typescript-eslint/restrict-plus-operands': off #TODO temporarily disabled
+      '@typescript-eslint/restrict-template-expressions': off #TODO temporarily disabled
       '@typescript-eslint/sort-type-union-intersection-members': off # TODO consider
       '@typescript-eslint/strict-boolean-expressions': off # TODO consider
-      '@typescript-eslint/switch-exhaustiveness-check': error
+      '@typescript-eslint/switch-exhaustiveness-check': off #TODO temporarily disabled
       '@typescript-eslint/triple-slash-reference': error
       '@typescript-eslint/typedef': off
       '@typescript-eslint/unbound-method': off # TODO consider
@@ -642,7 +582,7 @@ overrides:
       '@typescript-eslint/require-await': error
       '@typescript-eslint/return-await': error
 
-      # Disable for JS, Flow and TS
+      # Disable for JS and TS
       '@typescript-eslint/init-declarations': off
       '@typescript-eslint/no-magic-numbers': off
       '@typescript-eslint/no-use-before-define': off
@@ -665,10 +605,6 @@ overrides:
       '@typescript-eslint/space-before-function-paren': off
       '@typescript-eslint/space-infix-ops': off
       '@typescript-eslint/type-annotation-spacing': off
-  - files: 'src/**/*.d.ts'
-    rules:
-      import/order: off
-      import/newline-after-import: off
   - files: 'src/**/__*__/**'
     rules:
       node/no-unpublished-import: [error, { allowModules: ['chai', 'mocha'] }]

.github/CONTRIBUTING.md

@@ -73,7 +73,7 @@ ensure your pull request matches the style guides, run `npm run prettier`.
 - 80 character line length strongly preferred.
 - Prefer `'` over `"`
 - ES6 syntax when possible. However do not rely on ES6-specific functions to be available.
-- Use [Flow types](https://flowtype.org/).
+- Use [TypeScript](https://www.typescriptlang.org).
 - Use semicolons;
 - Trailing commas,
 - Avd abbr wrds.

.github/workflows/ci.yml

@@ -29,7 +29,7 @@ jobs:
       - name: Lint ESLint
         run: npm run lint
 
-      - name: Lint Flow
+      - name: Check Types
         run: npm run check
 
       - name: Lint Prettier

.mocharc.yml

@@ -1,4 +1,4 @@
 throw-deprecation: true
 check-leaks: true
 require:
-  - '@babel/register'
+  - 'resources/ts-register.js'

.prettierignore

@@ -1,5 +1,3 @@
-/flow-typed
-
 # Copied from '.gitignore', please keep it in sync.
 /.eslintcache
 /node_modules

cspell.yml

@@ -24,7 +24,6 @@ words:
   - graphiql
   - sublinks
   - instanceof
-  - flowtype
 
   # Different names used inside tests
   - Skywalker