feat(experimental-utils): move isTypeReadonly from eslint-plugin to e…

…xperimental-utils (#3658)

Co-authored-by: Brad Zacher <brad.zacher@gmail.com>

.github/ISSUE_TEMPLATE.md

@@ -73,6 +73,7 @@ i.e. eslint --ext ".ts,.js" src --debug
 | `@typescript-eslint/parser`             | `X.Y.Z` |
 | `@typescript-eslint/typescript-estree`  | `X.Y.Z` |
 | `@typescript-eslint/experimental-utils` | `X.Y.Z` |
+| `@typescript-eslint/type-utils`         | `X.Y.Z` |
 | `TypeScript`                            | `X.Y.Z` |
 | `node`                                  | `X.Y.Z` |
 | `npm`                                   | `X.Y.Z` |

.github/ISSUE_TEMPLATE/typescript-eslint-type-utils.md

@@ -0,0 +1,72 @@
+---
+name: '@typescript-eslint/type-utils'
+about: Report an issue with the '@typescript-eslint/type-utils' package
+title: ''
+labels: 'package: type-utils, triage'
+assignees: ''
+---
+
+<!--
+Please don't ignore this template.
+
+If you ignore it, we're just going to respond asking you to fill it out, which wastes everyone's time.
+The more relevant information you can include, the faster we can find the issue and fix it without asking you for more info.
+-->
+
+<!--
+🚨 STOP 🚨 𝗦𝗧𝗢𝗣 🚨 𝑺𝑻𝑶𝑷 🚨
+
+This issue template is only for problems specifically with the `@typescript-eslint/type-utils` package.
+
+If you have a problem with a specific lint rule, please back out and select the `@typescript-eslint/eslint-plugin` template.
+If you have a problem with the parser, please back out and select the `@typescript-eslint/parser` template.
+-->
+
+- [ ] I have tried restarting my IDE and the issue persists.
+- [ ] I have updated to the latest version of the packages.
+- [ ] I have [read the FAQ](https://github.com/typescript-eslint/typescript-eslint/blob/master/docs/getting-started/linting/FAQ.md) and my problem is not listed.
+
+**Repro**
+
+<!--
+Include a ***minimal*** reproduction case.
+The more irrelevant code/config you give, the harder it is for us to investigate.
+
+Please consider creating an isolated reproduction repo to make it easy for the volunteer maintainers debug your issue.
+-->
+
+```TS
+// your repro code case
+```
+
+**Expected Result**
+
+<!--
+What did you expect to happen?
+Please be specific here - list the exact lines and messages you expect.
+-->
+
+**Actual Result**
+
+<!--
+What actually happened?
+Please be specific here - list the exact lines and messages that caused errors
+-->
+
+**Additional Info**
+
+<!--
+Did eslint throw an exception?
+
+Please run your lint again with the --debug flag, and dump the output below.
+i.e. eslint --ext ".ts,.js" src --debug
+-->
+
+**Versions**
+
+| package                         | version |
+| ------------------------------- | ------- |
+| `@typescript-eslint/type-utils` | `X.Y.Z` |
+| `@typescript-eslint/type-utils` | `X.Y.Z` |
+| `TypeScript`                    | `X.Y.Z` |
+| `node`                          | `X.Y.Z` |

.github/workflows/ci.yml

@@ -116,6 +116,11 @@ jobs:
         env:
           CI: true
 
+      - name: Run unit tests for type-utils
+        run: npx nx test @typescript-eslint/type-utils
+        env:
+          CI: true
+
       - name: Run unit tests for parser
         run: npx nx test @typescript-eslint/parser
         env:
@@ -283,6 +288,11 @@ jobs:
         env:
           CI: true
 
+      - name: Run unit tests for type-utils
+        run: npx nx test @typescript-eslint/type-utils
+        env:
+          CI: true
+
       - name: Run unit tests for parser
         run: npx nx test @typescript-eslint/parser
         env:

.vscode/launch.json

@@ -24,6 +24,8 @@
         "${workspaceFolder}/packages/experimental-utils/dist/index.js",
         "${workspaceFolder}/packages/experimental-utils/src/ts-estree.ts",
         "${workspaceFolder}/packages/experimental-utils/dist/ts-estree.js",
+        "${workspaceFolder}/packages/type-utils/src/index.ts",
+        "${workspaceFolder}/packages/type-utils/dist/index.js",
         "${workspaceFolder}/packages/parser/src/index.ts",
         "${workspaceFolder}/packages/parser/dist/index.js",
         "${workspaceFolder}/packages/typescript-estree/src/index.ts",
@@ -56,6 +58,8 @@
         "${workspaceFolder}/packages/experimental-utils/dist/index.js",
         "${workspaceFolder}/packages/experimental-utils/src/ts-estree.ts",
         "${workspaceFolder}/packages/experimental-utils/dist/ts-estree.js",
+        "${workspaceFolder}/packages/type-utils/src/index.ts",
+        "${workspaceFolder}/packages/type-utils/dist/index.js",
         "${workspaceFolder}/packages/parser/src/index.ts",
         "${workspaceFolder}/packages/parser/dist/index.js",
         "${workspaceFolder}/packages/typescript-estree/src/index.ts",
@@ -88,6 +92,8 @@
         "${workspaceFolder}/packages/experimental-utils/dist/index.js",
         "${workspaceFolder}/packages/experimental-utils/src/ts-estree.ts",
         "${workspaceFolder}/packages/experimental-utils/dist/ts-estree.js",
+        "${workspaceFolder}/packages/type-utils/src/ts-estree.ts",
+        "${workspaceFolder}/packages/type-utils/dist/ts-estree.js",
         "${workspaceFolder}/packages/parser/src/index.ts",
         "${workspaceFolder}/packages/parser/dist/index.js",
         "${workspaceFolder}/packages/typescript-estree/src/index.ts",
@@ -120,6 +126,8 @@
         "${workspaceFolder}/packages/experimental-utils/dist/index.js",
         "${workspaceFolder}/packages/experimental-utils/src/ts-estree.ts",
         "${workspaceFolder}/packages/experimental-utils/dist/ts-estree.js",
+        "${workspaceFolder}/packages/type-utils/src/index.ts",
+        "${workspaceFolder}/packages/type-utils/dist/index.js",
         "${workspaceFolder}/packages/parser/src/index.ts",
         "${workspaceFolder}/packages/parser/dist/index.js",
         "${workspaceFolder}/packages/typescript-estree/src/index.ts",
@@ -152,6 +160,42 @@
         "${workspaceFolder}/packages/experimental-utils/dist/index.js",
         "${workspaceFolder}/packages/experimental-utils/src/ts-estree.ts",
         "${workspaceFolder}/packages/experimental-utils/dist/ts-estree.js",
+        "${workspaceFolder}/packages/type-utils/src/index.ts",
+        "${workspaceFolder}/packages/type-utils/dist/index.js",
+        "${workspaceFolder}/packages/parser/src/index.ts",
+        "${workspaceFolder}/packages/parser/dist/index.js",
+        "${workspaceFolder}/packages/typescript-estree/src/index.ts",
+        "${workspaceFolder}/packages/typescript-estree/dist/index.js",
+        "${workspaceFolder}/packages/types/src/index.ts",
+        "${workspaceFolder}/packages/types/dist/index.js",
+        "${workspaceFolder}/packages/visitor-keys/src/index.ts",
+        "${workspaceFolder}/packages/visitor-keys/dist/index.js",
+        "${workspaceFolder}/packages/scope-manager/dist/index.js",
+        "${workspaceFolder}/packages/scope-manager/dist/index.js",
+      ],
+    },
+    {
+      "type": "node",
+      "request": "launch",
+      "name": "Run currently opened type-utils test",
+      "cwd": "${workspaceFolder}/packages/type-utils/",
+      "program": "${workspaceFolder}/node_modules/jest/bin/jest.js",
+      "args": [
+        "--runInBand",
+        "--no-cache",
+        "--no-coverage",
+        "${fileBasenameNoExtension}"
+      ],
+      "sourceMaps": true,
+      "console": "integratedTerminal",
+      "internalConsoleOptions": "neverOpen",
+      "skipFiles": [
+        "${workspaceFolder}/packages/experimental-utils/src/index.ts",
+        "${workspaceFolder}/packages/experimental-utils/dist/index.js",
+        "${workspaceFolder}/packages/experimental-utils/src/ts-estree.ts",
+        "${workspaceFolder}/packages/experimental-utils/dist/ts-estree.js",
+        "${workspaceFolder}/packages/type-utils/src/index.ts",
+        "${workspaceFolder}/packages/type-utils/dist/index.js",
         "${workspaceFolder}/packages/parser/src/index.ts",
         "${workspaceFolder}/packages/parser/dist/index.js",
         "${workspaceFolder}/packages/typescript-estree/src/index.ts",
@@ -184,6 +228,8 @@
         "${workspaceFolder}/packages/experimental-utils/dist/index.js",
         "${workspaceFolder}/packages/experimental-utils/src/ts-estree.ts",
         "${workspaceFolder}/packages/experimental-utils/dist/ts-estree.js",
+        "${workspaceFolder}/packages/type-utils/src/index.ts",
+        "${workspaceFolder}/packages/type-utils/dist/index.js",
         "${workspaceFolder}/packages/parser/src/index.ts",
         "${workspaceFolder}/packages/parser/dist/index.js",
         "${workspaceFolder}/packages/typescript-estree/src/index.ts",

package.json

@@ -44,7 +44,6 @@
     "start": "nx run website:start",
     "test": "nx run-many --target=test --all --parallel",
     "test-integration": "yarn jest -c ./tests/integration/jest.config.js",
-    "test-kill-integration-containers": "docker-compose -f tests/integration/docker-compose.yml down -v --rmi local",
     "typecheck": "nx run-many --target=typecheck --all --parallel"
   },
   "config": {

packages/ast-spec/README.md

@@ -16,7 +16,7 @@ It includes:
 
 **You probably don't want to use it directly.**
 
-If you're building an ESLint plugin, consider using [`@typescript-eslint/experimental-utils`](../experimental-utils).
+If you're building an ESLint plugin, consider using [`@typescript-eslint/experimental-utils`](../experimental-utils) and [`@typescript-eslint/type-utils`](../type-utils).
 If you're parsing TypeScript code, consider using [`@typescript-eslint/typescript-estree`](../typescript-estree).
 
 ## Contributing

packages/eslint-plugin/package.json

@@ -46,6 +46,7 @@
   "dependencies": {
     "@typescript-eslint/experimental-utils": "5.8.1",
     "@typescript-eslint/scope-manager": "5.8.1",
+    "@typescript-eslint/type-utils": "5.8.1",
     "debug": "^4.3.2",
     "functional-red-black-tree": "^1.0.1",
     "ignore": "^5.1.8",

packages/eslint-plugin/src/rules/no-unnecessary-boolean-literal-compare.ts

@@ -158,7 +158,7 @@ export default util.createRule<Options, MessageIds>({
     function deconstructComparison(
       node: TSESTree.BinaryExpression,
     ): BooleanComparison | undefined {
-      const comparisonType = util.getEqualsKind(node.operator);
+      const comparisonType = getEqualsKind(node.operator);
       if (!comparisonType) {
         return undefined;
       }
@@ -275,3 +275,39 @@ export default util.createRule<Options, MessageIds>({
     };
   },
 });
+
+interface EqualsKind {
+  isPositive: boolean;
+  isStrict: boolean;
+}
+
+function getEqualsKind(operator: string): EqualsKind | undefined {
+  switch (operator) {
+    case '==':
+      return {
+        isPositive: true,
+        isStrict: false,
+      };
+
+    case '===':
+      return {
+        isPositive: true,
+        isStrict: true,
+      };
+
+    case '!=':
+      return {
+        isPositive: false,
+        isStrict: false,
+      };
+
+    case '!==':
+      return {
+        isPositive: false,
+        isStrict: true,
+      };
+
+    default:
+      return undefined;
+  }
+}

packages/eslint-plugin/src/rules/no-unnecessary-condition.ts

@@ -17,14 +17,14 @@ import {
   createRule,
   getParserServices,
   getConstrainedTypeAtLocation,
+  getTypeOfPropertyOfName,
   isNullableType,
   nullThrows,
   NullThrowsReasons,
   isIdentifier,
   isTypeAnyType,
   isTypeUnknownType,
   getTypeName,
-  getTypeOfPropertyOfName,
 } from '../util';
 
 // Truthiness utilities

packages/eslint-plugin/src/util/collectUnusedVariables.ts

@@ -3,10 +3,10 @@ import {
   TSESLint,
   ASTUtils,
   TSESTree,
+  ESLintUtils,
 } from '@typescript-eslint/experimental-utils';
 import { ImplicitLibVariable } from '@typescript-eslint/scope-manager';
 import { Visitor } from '@typescript-eslint/scope-manager/dist/referencer/Visitor';
-import { nullThrows } from './nullThrows';
 
 class UnusedVarsVisitor<
   TMessageIds extends string,
@@ -25,7 +25,7 @@ class UnusedVarsVisitor<
       visitChildrenEvenIfSelectorExists: true,
     });
 
-    this.#scopeManager = nullThrows(
+    this.#scopeManager = ESLintUtils.nullThrows(
       context.getSourceCode().scopeManager,
       'Missing required scope manager',
     );

packages/eslint-plugin/src/util/explicitReturnTypeUtils.ts

@@ -1,11 +1,11 @@
 import {
   TSESTree,
   AST_NODE_TYPES,
+  ESLintUtils,
   TSESLint,
 } from '@typescript-eslint/experimental-utils';
 import { isTypeAssertion, isConstructor, isSetter } from './astUtils';
 import { getFunctionHeadLoc } from './getFunctionHeadLoc';
-import { nullThrows, NullThrowsReasons } from './nullThrows';
 
 type FunctionExpression =
   | TSESTree.ArrowFunctionExpression
@@ -187,7 +187,10 @@ function isTypedFunctionExpression(
   node: FunctionExpression,
   options: Options,
 ): boolean {
-  const parent = nullThrows(node.parent, NullThrowsReasons.MissingParent);
+  const parent = ESLintUtils.nullThrows(
+    node.parent,
+    ESLintUtils.NullThrowsReasons.MissingParent,
+  );
 
   if (!options.allowTypedFunctionExpressions) {
     return false;
@@ -215,7 +218,10 @@ function isValidFunctionExpressionReturnType(
     return true;
   }
 
-  const parent = nullThrows(node.parent, NullThrowsReasons.MissingParent);
+  const parent = ESLintUtils.nullThrows(
+    node.parent,
+    ESLintUtils.NullThrowsReasons.MissingParent,
+  );
   if (
     options.allowExpressions &&
     parent.type !== AST_NODE_TYPES.VariableDeclarator &&

packages/eslint-plugin/src/util/getESLintCoreRule.ts

@@ -1,6 +1,6 @@
+import { ESLintUtils } from '@typescript-eslint/experimental-utils';
 import { version } from 'eslint/package.json';
 import * as semver from 'semver';
-import { nullThrows } from './nullThrows';
 
 const isESLintV8 = semver.major(version) >= 8;
 
@@ -42,7 +42,7 @@ type RuleId = keyof RuleMap;
 export const getESLintCoreRule: <R extends RuleId>(ruleId: R) => RuleMap[R] =
   isESLintV8
     ? <R extends RuleId>(ruleId: R): RuleMap[R] =>
-        nullThrows(
+        ESLintUtils.nullThrows(
           // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access, @typescript-eslint/no-unsafe-call
           require('eslint/use-at-your-own-risk').builtinRules.get(
             ruleId,

packages/eslint-plugin/src/util/getWrappingFixer.ts

@@ -4,7 +4,6 @@ import {
   ASTUtils,
   TSESTree,
 } from '@typescript-eslint/experimental-utils';
-import { SourceCode } from '@typescript-eslint/experimental-utils/src/ts-eslint';
 
 interface WrappingFixerParams {
   /** Source code. */
@@ -135,7 +134,7 @@ function isWeakPrecedenceParent(node: TSESTree.Node): boolean {
  */
 function isMissingSemicolonBefore(
   node: TSESTree.Node,
-  sourceCode: SourceCode,
+  sourceCode: TSESLint.SourceCode,
 ): boolean {
   for (;;) {
     const parent = node.parent!;