chore: run ESLint with types om more packages (#13372)

packages/jest-docblock/src/index.ts

@@ -39,7 +39,7 @@ export function parseWithComments(docblock: string): {
   comments: string;
   pragmas: Pragmas;
 } {
-  const line = detectNewline(docblock) || EOL;
+  const line = detectNewline(docblock) ?? EOL;
 
   docblock = docblock
     .replace(commentStartRe, '')
@@ -54,7 +54,7 @@ export function parseWithComments(docblock: string): {
   }
   docblock = docblock.replace(ltrimNewlineRe, '').trimRight();
 
-  const result = Object.create(null);
+  const result = Object.create(null) as Pragmas;
   const comments = docblock
     .replace(propertyRe, '')
     .replace(ltrimNewlineRe, '')
@@ -83,7 +83,7 @@ export function print({
   comments?: string;
   pragmas?: Pragmas;
 }): string {
-  const line = detectNewline(comments) || EOL;
+  const line = detectNewline(comments) ?? EOL;
   const head = '/**';
   const start = ' *';
   const tail = ' */';

packages/jest-environment-jsdom/src/index.ts

@@ -26,6 +26,10 @@ type Win = Window &
     };
   };
 
+function isString(value: unknown): value is string {
+  return typeof value === 'string';
+}
+
 export default class JSDOMEnvironment implements JestEnvironment<number> {
   dom: JSDOM | null;
   fakeTimers: LegacyFakeTimers<number> | null;
@@ -65,33 +69,33 @@ export default class JSDOMEnvironment implements JestEnvironment<number> {
     const global = (this.global = this.dom.window.document
       .defaultView as unknown as Win);
 
-    if (!global) {
+    if (global == null) {
       throw new Error('JSDOM did not return a Window object');
     }
 
-    // for "universal" code (code should use `globalThis`)
-    global.global = global as any;
+    // @ts-expect-error - for "universal" code (code should use `globalThis`)
+    global.global = global;
 
     // Node's error-message stack size is limited at 10, but it's pretty useful
     // to see more than that when a test fails.
     this.global.Error.stackTraceLimit = 100;
-    installCommonGlobals(global as any, projectConfig.globals);
+    installCommonGlobals(global, projectConfig.globals);
 
     // TODO: remove this ASAP, but it currently causes tests to run really slow
     global.Buffer = Buffer;
 
     // Report uncaught errors.
     this.errorEventListener = event => {
-      if (userErrorListenerCount === 0 && event.error) {
+      if (userErrorListenerCount === 0 && event.error != null) {
         process.emit('uncaughtException', event.error);
       }
     };
     global.addEventListener('error', this.errorEventListener);
 
     // However, don't report them as uncaught if the user listens to 'error' event.
     // In that case, we assume the might have custom error handling logic.
-    const originalAddListener = global.addEventListener;
-    const originalRemoveListener = global.removeEventListener;
+    const originalAddListener = global.addEventListener.bind(global);
+    const originalRemoveListener = global.removeEventListener.bind(global);
     let userErrorListenerCount = 0;
     global.addEventListener = function (
       ...args: Parameters<typeof originalAddListener>
@@ -114,7 +118,7 @@ export default class JSDOMEnvironment implements JestEnvironment<number> {
       const {customExportConditions} = projectConfig.testEnvironmentOptions;
       if (
         Array.isArray(customExportConditions) &&
-        customExportConditions.every(item => typeof item === 'string')
+        customExportConditions.every(isString)
       ) {
         this.customExportConditions = customExportConditions;
       } else {
@@ -124,7 +128,7 @@ export default class JSDOMEnvironment implements JestEnvironment<number> {
       }
     }
 
-    this.moduleMocker = new ModuleMocker(global as any);
+    this.moduleMocker = new ModuleMocker(global);
 
     this.fakeTimers = new LegacyFakeTimers({
       config: projectConfig,
@@ -152,7 +156,7 @@ export default class JSDOMEnvironment implements JestEnvironment<number> {
     if (this.fakeTimersModern) {
       this.fakeTimersModern.dispose();
     }
-    if (this.global) {
+    if (this.global != null) {
       if (this.errorEventListener) {
         this.global.removeEventListener('error', this.errorEventListener);
       }

packages/jest-environment-node/src/__tests__/node_environment.test.ts

@@ -5,44 +5,60 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+import type {EnvironmentContext} from '@jest/environment';
 import {makeGlobalConfig, makeProjectConfig} from '@jest/test-utils';
 import NodeEnvironment from '../';
 
+const context: EnvironmentContext = {
+  console,
+  docblockPragmas: {},
+  testPath: __filename,
+};
+
 describe('NodeEnvironment', () => {
   it('uses a copy of the process object', () => {
     const testEnvConfig = {
       globalConfig: makeGlobalConfig(),
       projectConfig: makeProjectConfig(),
     };
-    const env1 = new NodeEnvironment(testEnvConfig);
-    const env2 = new NodeEnvironment(testEnvConfig);
+    const env1 = new NodeEnvironment(testEnvConfig, context);
+    const env2 = new NodeEnvironment(testEnvConfig, context);
 
     expect(env1.global.process).not.toBe(env2.global.process);
   });
 
   it('exposes process.on', () => {
-    const env1 = new NodeEnvironment({
-      globalConfig: makeGlobalConfig(),
-      projectConfig: makeProjectConfig(),
-    });
+    const env1 = new NodeEnvironment(
+      {
+        globalConfig: makeGlobalConfig(),
+        projectConfig: makeProjectConfig(),
+      },
+      context,
+    );
 
     expect(env1.global.process.on).not.toBeNull();
   });
 
   it('exposes global.global', () => {
-    const env1 = new NodeEnvironment({
-      globalConfig: makeGlobalConfig(),
-      projectConfig: makeProjectConfig(),
-    });
+    const env1 = new NodeEnvironment(
+      {
+        globalConfig: makeGlobalConfig(),
+        projectConfig: makeProjectConfig(),
+      },
+      context,
+    );
 
     expect(env1.global.global).toBe(env1.global);
   });
 
   it('should configure setTimeout/setInterval to use the node api', () => {
-    const env1 = new NodeEnvironment({
-      globalConfig: makeGlobalConfig(),
-      projectConfig: makeProjectConfig(),
-    });
+    const env1 = new NodeEnvironment(
+      {
+        globalConfig: makeGlobalConfig(),
+        projectConfig: makeProjectConfig(),
+      },
+      context,
+    );
 
     env1.fakeTimers!.useFakeTimers();
 
@@ -57,10 +73,13 @@ describe('NodeEnvironment', () => {
   });
 
   it('has modern fake timers implementation', () => {
-    const env = new NodeEnvironment({
-      globalConfig: makeGlobalConfig(),
-      projectConfig: makeProjectConfig(),
-    });
+    const env = new NodeEnvironment(
+      {
+        globalConfig: makeGlobalConfig(),
+        projectConfig: makeProjectConfig(),
+      },
+      context,
+    );
 
     expect(env.fakeTimersModern).toBeDefined();
   });

packages/jest-environment-node/src/index.ts

@@ -53,6 +53,10 @@ const nodeGlobals = new Map(
     }),
 );
 
+function isString(value: unknown): value is string {
+  return typeof value === 'string';
+}
+
 export default class NodeEnvironment implements JestEnvironment<Timer> {
   context: Context | null;
   fakeTimers: LegacyFakeTimers<Timer> | null;
@@ -65,10 +69,11 @@ export default class NodeEnvironment implements JestEnvironment<Timer> {
   constructor(config: JestEnvironmentConfig, _context: EnvironmentContext) {
     const {projectConfig} = config;
     this.context = createContext();
-    const global = (this.global = runInContext(
+    const global = runInContext(
       'this',
       Object.assign(this.context, projectConfig.testEnvironmentOptions),
-    ));
+    ) as Global.Global;
+    this.global = global;
 
     const contextGlobals = new Set(Object.getOwnPropertyNames(global));
     for (const [nodeGlobalsKey, descriptor] of nodeGlobals) {
@@ -78,7 +83,7 @@ export default class NodeEnvironment implements JestEnvironment<Timer> {
           enumerable: descriptor.enumerable,
           get() {
             // @ts-expect-error: no index signature
-            const val = globalThis[nodeGlobalsKey];
+            const val = globalThis[nodeGlobalsKey] as unknown;
 
             // override lazy getter
             Object.defineProperty(global, nodeGlobalsKey, {
@@ -89,7 +94,7 @@ export default class NodeEnvironment implements JestEnvironment<Timer> {
             });
             return val;
           },
-          set(val) {
+          set(val: unknown) {
             // override lazy getter
             Object.defineProperty(global, nodeGlobalsKey, {
               configurable: descriptor.configurable,
@@ -102,6 +107,7 @@ export default class NodeEnvironment implements JestEnvironment<Timer> {
       }
     }
 
+    // @ts-expect-error - Buffer and gc is "missing"
     global.global = global;
     global.Buffer = Buffer;
     global.ArrayBuffer = ArrayBuffer;
@@ -120,7 +126,7 @@ export default class NodeEnvironment implements JestEnvironment<Timer> {
       const {customExportConditions} = projectConfig.testEnvironmentOptions;
       if (
         Array.isArray(customExportConditions) &&
-        customExportConditions.every(item => typeof item === 'string')
+        customExportConditions.every(isString)
       ) {
         this.customExportConditions = customExportConditions;
       } else {
@@ -142,8 +148,7 @@ export default class NodeEnvironment implements JestEnvironment<Timer> {
       },
     });
 
-    const timerRefToId = (timer: Timer): number | undefined =>
-      (timer && timer.id) || undefined;
+    const timerRefToId = (timer: Timer): number | undefined => timer?.id;
 
     this.fakeTimers = new LegacyFakeTimers({
       config: projectConfig,

packages/jest-globals/src/__tests__/index.ts

@@ -6,7 +6,9 @@
  */
 
 test('throw when directly imported', () => {
-  expect(() => require('../')).toThrow(
+  expect(() => {
+    require('../');
+  }).toThrow(
     'Do not import `@jest/globals` outside of the Jest test environment',
   );
 });

packages/jest-resolve-dependencies/src/__tests__/dependency_resolver.test.ts

@@ -16,7 +16,6 @@ import {DependencyResolver} from '../index';
 const maxWorkers = 1;
 let dependencyResolver: DependencyResolver;
 let runtimeContextResolver: Resolver;
-let Runtime: typeof import('jest-runtime').default;
 let config: Config.ProjectConfig;
 const cases: Record<string, (path: string) => boolean> = {
   fancyCondition: path => path.length > 10,
@@ -26,7 +25,8 @@ const filter = (path: string) =>
   Object.keys(cases).every(key => cases[key](path));
 
 beforeEach(async () => {
-  Runtime = require('jest-runtime').default;
+  const Runtime = (require('jest-runtime') as typeof import('jest-runtime'))
+    .default;
   config = makeProjectConfig({
     cacheDirectory: path.resolve(tmpdir(), 'jest-resolve-dependencies-test'),
     moduleDirectories: ['node_modules'],

packages/jest-resolve-dependencies/src/index.ts

@@ -61,7 +61,7 @@ export class DependencyResolver {
         }
       }
 
-      if (!resolvedDependency) {
+      if (resolvedDependency == null) {
         return acc;
       }
 
@@ -78,7 +78,7 @@ export class DependencyResolver {
         // leave resolvedMockDependency as undefined if nothing can be found
       }
 
-      if (resolvedMockDependency) {
+      if (resolvedMockDependency != null) {
         const dependencyMockDir = path.resolve(
           path.dirname(resolvedDependency),
           '__mocks__',

packages/jest-test-result/src/formatTestResults.ts

@@ -7,10 +7,8 @@
 
 import type {
   AggregatedResult,
-  AssertionResult,
   CodeCoverageFormatter,
   CodeCoverageReporter,
-  FormattedAssertionResult,
   FormattedTestResult,
   FormattedTestResults,
   TestResult,
@@ -21,55 +19,35 @@ const formatTestResult = (
   codeCoverageFormatter?: CodeCoverageFormatter,
   reporter?: CodeCoverageReporter,
 ): FormattedTestResult => {
-  const assertionResults = testResult.testResults.map(formatTestAssertion);
   if (testResult.testExecError) {
     const now = Date.now();
     return {
-      assertionResults,
+      assertionResults: testResult.testResults,
       coverage: {},
       endTime: now,
-      message: testResult.failureMessage
-        ? testResult.failureMessage
-        : testResult.testExecError.message,
+      message: testResult.failureMessage ?? testResult.testExecError.message,
       name: testResult.testFilePath,
       startTime: now,
       status: 'failed',
       summary: '',
     };
-  } else {
-    const allTestsPassed = testResult.numFailingTests === 0;
-    return {
-      assertionResults,
-      coverage: codeCoverageFormatter
-        ? codeCoverageFormatter(testResult.coverage, reporter)
-        : testResult.coverage,
-      endTime: testResult.perfStats.end,
-      message: testResult.failureMessage || '',
-      name: testResult.testFilePath,
-      startTime: testResult.perfStats.start,
-      status: allTestsPassed ? 'passed' : 'failed',
-      summary: '',
-    };
   }
-};
 
-function formatTestAssertion(
-  assertion: AssertionResult,
-): FormattedAssertionResult {
-  const result: FormattedAssertionResult = {
-    ancestorTitles: assertion.ancestorTitles,
-    duration: assertion.duration,
-    failureMessages: null,
-    fullName: assertion.fullName,
-    location: assertion.location,
-    status: assertion.status,
-    title: assertion.title,
+  const allTestsPassed = testResult.numFailingTests === 0;
+  return {
+    assertionResults: testResult.testResults,
+    coverage:
+      codeCoverageFormatter != null
+        ? codeCoverageFormatter(testResult.coverage, reporter)
+        : testResult.coverage,
+    endTime: testResult.perfStats.end,
+    message: testResult.failureMessage ?? '',
+    name: testResult.testFilePath,
+    startTime: testResult.perfStats.start,
+    status: allTestsPassed ? 'passed' : 'failed',
+    summary: '',
   };
-  if (assertion.failureMessages) {
-    result.failureMessages = assertion.failureMessages;
-  }
-  return result;
-}
+};
 
 export default function formatTestResults(
   results: AggregatedResult,