chore: upgrade to typescript 3.9 (#10031)

Author: SimenB

.eslintrc.js

@@ -26,6 +26,7 @@ module.exports = {
           'error',
           {argsIgnorePattern: '^_'},
         ],
+        '@typescript-eslint/prefer-ts-expect-error': 'error',
         // Since we do `export =`. Remove for Jest 25
         'import/default': 'off',
         'import/order': 'error',

package.json

@@ -73,7 +73,7 @@
     "strip-ansi": "^6.0.0",
     "tempy": "^0.5.0",
     "throat": "^5.0.0",
-    "typescript": "^3.8.2",
+    "typescript": "^3.9.2",
     "which": "^2.0.1"
   },
   "scripts": {

packages/babel-plugin-jest-hoist/src/index.ts

@@ -113,7 +113,7 @@ FUNCTIONS.mock = args => {
 
     const ids: Set<NodePath<Identifier>> = new Set();
     const parentScope = moduleFactory.parentPath.scope;
-    // @ts-ignore: ReferencedIdentifier is not known on visitors
+    // @ts-expect-error: ReferencedIdentifier is not known on visitors
     moduleFactory.traverse(IDVisitor, {ids});
     for (const id of ids) {
       const {name} = id.node;

packages/jest-circus/src/__tests__/circusItTestError.test.ts

@@ -29,21 +29,21 @@ describe('test/it error throwing', () => {
   });
   it(`it throws error with missing callback function`, () => {
     expect(() => {
-      // @ts-ignore: Easy, we're testing runtime errors here
+      // @ts-expect-error: Easy, we're testing runtime errors here
       circusIt('test2');
     }).toThrowError(
       'Missing second argument. It must be a callback function. Perhaps you want to use `test.todo` for a test placeholder.',
     );
   });
   it(`it throws an error when first argument isn't a string`, () => {
     expect(() => {
-      // @ts-ignore: Easy, we're testing runtime errors here
+      // @ts-expect-error: Easy, we're testing runtime errors here
       circusIt(() => {});
     }).toThrowError('Invalid first argument, () => {}. It must be a string.');
   });
   it('it throws an error when callback function is not a function', () => {
     expect(() => {
-      // @ts-ignore: Easy, we're testing runtime errors here
+      // @ts-expect-error: Easy, we're testing runtime errors here
       circusIt('test4', 'test4b');
     }).toThrowError(
       'Invalid second argument, test4b. It must be a callback function.',
@@ -56,21 +56,21 @@ describe('test/it error throwing', () => {
   });
   it(`test throws error with missing callback function`, () => {
     expect(() => {
-      // @ts-ignore: Easy, we're testing runtime errors here
+      // @ts-expect-error: Easy, we're testing runtime errors here
       circusTest('test6');
     }).toThrowError(
       'Missing second argument. It must be a callback function. Perhaps you want to use `test.todo` for a test placeholder.',
     );
   });
   it(`test throws an error when first argument isn't a string`, () => {
     expect(() => {
-      // @ts-ignore: Easy, we're testing runtime errors here
+      // @ts-expect-error: Easy, we're testing runtime errors here
       circusTest(() => {});
     }).toThrowError('Invalid first argument, () => {}. It must be a string.');
   });
   it('test throws an error when callback function is not a function', () => {
     expect(() => {
-      // @ts-ignore: Easy, we're testing runtime errors here
+      // @ts-expect-error: Easy, we're testing runtime errors here
       circusTest('test8', 'test8b');
     }).toThrowError(
       'Invalid second argument, test8b. It must be a callback function.',

packages/jest-circus/src/__tests__/circusItTodoTestError.test.ts

@@ -22,7 +22,7 @@ aliasCircusIt();
 describe('test/it.todo error throwing', () => {
   it('todo throws error when given no arguments', () => {
     expect(() => {
-      // @ts-ignore: Testing runtime errors here
+      // @ts-expect-error: Testing runtime errors here
       circusIt.todo();
     }).toThrowError('Todo must be called with only a description.');
   });
@@ -33,7 +33,7 @@ describe('test/it.todo error throwing', () => {
   });
   it('todo throws error when given none string description', () => {
     expect(() => {
-      // @ts-ignore: Testing runtime errors here
+      // @ts-expect-error: Testing runtime errors here
       circusIt.todo(() => {});
     }).toThrowError('Todo must be called with only a description.');
   });

packages/jest-cli/src/__tests__/cli/args.test.ts

@@ -101,11 +101,11 @@ describe('check', () => {
 
 describe('buildArgv', () => {
   it('should return only camelcased args ', () => {
-    // @ts-ignore
+    // @ts-expect-error
     const mockProcessArgv = jest
       .spyOn(process.argv, 'slice')
       .mockImplementation(() => ['--clear-mocks']);
-    // @ts-ignore
+    // @ts-expect-error
     const actual = buildArgv(null);
     expect(actual).not.toHaveProperty('clear-mocks');
     expect(actual).toHaveProperty('clearMocks', true);

packages/jest-cli/src/init/index.ts

@@ -108,7 +108,7 @@ export default async (
 
   let promptAborted: boolean = false;
 
-  // @ts-ignore: Return type cannot be object - faulty typings
+  // @ts-expect-error: Return type cannot be object - faulty typings
   const results: PromptsResults = await prompts(questions, {
     onCancel: () => {
       promptAborted = true;

packages/jest-config/src/__tests__/getMaxWorkers.test.ts

@@ -39,19 +39,19 @@ describe('getMaxWorkers', () => {
   describe('% based', () => {
     it('50% = 2 workers', () => {
       const argv = {maxWorkers: '50%'};
-      // @ts-ignore: need to fix the typing
+      // @ts-expect-error: need to fix the typing
       expect(getMaxWorkers(argv)).toBe(2);
     });
 
     it('< 0 workers should become 1', () => {
       const argv = {maxWorkers: '1%'};
-      // @ts-ignore: need to fix the typing
+      // @ts-expect-error: need to fix the typing
       expect(getMaxWorkers(argv)).toBe(1);
     });
 
     it("0% shouldn't break", () => {
       const argv = {maxWorkers: '0%'};
-      // @ts-ignore: need to fix the typing
+      // @ts-expect-error: need to fix the typing
       expect(getMaxWorkers(argv)).toBe(1);
     });
   });

packages/jest-config/src/__tests__/readConfig.test.ts

@@ -10,7 +10,7 @@ import {readConfig} from '../index';
 test('readConfig() throws when an object is passed without a file path', async () => {
   await expect(
     readConfig(
-      // @ts-ignore
+      // @ts-expect-error
       null /* argv */,
       {} /* packageRootOrConfig */,
       false /* skipArgvConfigOption */,

packages/jest-config/src/__tests__/readConfigs.test.ts

@@ -19,7 +19,7 @@ jest.mock('../readConfigFileAndSetRootDir', () => jest.fn(() => mockResult));
 
 test('readConfigs() throws when called without project paths', async () => {
   await expect(
-    // @ts-ignore
+    // @ts-expect-error
     readConfigs(null /* argv */, [] /* projectPaths */),
   ).rejects.toThrowError('jest: No configuration found for any project.');
 });
@@ -29,7 +29,7 @@ test('readConfigs() loads async config file', async () => {
     rootDir: './',
   }));
   await expect(
-    // @ts-ignore
+    // @ts-expect-error
     readConfigs(
       <Config.Argv>{} /* argv */,
       ['./some-jest-config-file.js'] /* projectPaths */,
@@ -43,7 +43,7 @@ test('readConfigs() reject if async was rejected', async () => {
     throw new Error('Some error');
   });
   await expect(
-    // @ts-ignore
+    // @ts-expect-error
     readConfigs(
       <Config.Argv>{} /* argv */,
       ['./some-jest-config-file.js'] /* projectPaths */,