chore: run eslint with type information on CI

.github/workflows/nodejs.yml

@@ -54,6 +54,8 @@ jobs:
         run: yarn typecheck:examples
       - name: typecheck tests
         run: yarn typecheck:tests
+      - name: run ESLint with type info
+        run: yarn lint-ts-files
 
   lint:
     name: Lint

package.json

@@ -103,6 +103,7 @@
     "lint:prettier-script": "prettier . \"!**/*.{js,jsx,cjs,mjs,ts,tsx}\" --cache",
     "lint:prettier": "yarn lint:prettier-script --write",
     "lint:prettier:ci": "yarn lint:prettier-script --check",
+    "lint-ts-files": "node scripts/lintTs.mjs",
     "remove-examples": "node ./scripts/remove-examples.mjs",
     "test-ci-partial": "yarn test-ci-partial:parallel -i",
     "test-ci-partial:parallel": "yarn jest --color --config jest.config.ci.mjs",

packages/babel-jest/src/__tests__/getCacheKey.test.ts

@@ -52,7 +52,8 @@ describe('getCacheKey', () => {
       readFileSync: () => 'new this file',
     }));
 
-    const {createTransformer}: typeof import('../index') = require('../index');
+    const {createTransformer} =
+      require('../index') as typeof import('../index');
 
     const newCacheKey = createTransformer().getCacheKey!(
       sourceText,
@@ -65,7 +66,7 @@ describe('getCacheKey', () => {
 
   test('if `babelOptions.options` value is changing', () => {
     jest.doMock('../loadBabelConfig', () => {
-      const babel: typeof import('@babel/core') = require('@babel/core');
+      const babel = require('@babel/core') as typeof import('@babel/core');
 
       return {
         loadPartialConfig: (options: BabelTransformOptions) => ({
@@ -75,7 +76,8 @@ describe('getCacheKey', () => {
       };
     });
 
-    const {createTransformer}: typeof import('../index') = require('../index');
+    const {createTransformer} =
+      require('../index') as typeof import('../index');
 
     const newCacheKey = createTransformer().getCacheKey!(
       sourceText,
@@ -117,7 +119,7 @@ describe('getCacheKey', () => {
 
   test('if `babelOptions.config` value is changing', () => {
     jest.doMock('../loadBabelConfig', () => {
-      const babel: typeof import('@babel/core') = require('@babel/core');
+      const babel = require('@babel/core') as typeof import('@babel/core');
 
       return {
         loadPartialConfig: (options: BabelTransformOptions) => ({
@@ -127,7 +129,8 @@ describe('getCacheKey', () => {
       };
     });
 
-    const {createTransformer}: typeof import('../index') = require('../index');
+    const {createTransformer} =
+      require('../index') as typeof import('../index');
 
     const newCacheKey = createTransformer().getCacheKey!(
       sourceText,
@@ -140,7 +143,7 @@ describe('getCacheKey', () => {
 
   test('if `babelOptions.babelrc` value is changing', () => {
     jest.doMock('../loadBabelConfig', () => {
-      const babel: typeof import('@babel/core') = require('@babel/core');
+      const babel = require('@babel/core') as typeof import('@babel/core');
 
       return {
         loadPartialConfig: (options: BabelTransformOptions) => ({
@@ -150,7 +153,8 @@ describe('getCacheKey', () => {
       };
     });
 
-    const {createTransformer}: typeof import('../index') = require('../index');
+    const {createTransformer} =
+      require('../index') as typeof import('../index');
 
     const newCacheKey = createTransformer().getCacheKey!(
       sourceText,

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

@@ -13,14 +13,17 @@ import {makeProjectConfig} from '@jest/test-utils';
 import type {TransformOptions} from '@jest/transform';
 import babelJest, {createTransformer} from '../index';
 import {loadPartialConfig} from '../loadBabelConfig';
+
 jest.mock('../loadBabelConfig', () => {
   const actual =
     jest.requireActual<typeof import('@babel/core')>('@babel/core');
 
   return {
-    loadPartialConfig: jest.fn((...args) => actual.loadPartialConfig(...args)),
-    loadPartialConfigAsync: jest.fn((...args) =>
-      actual.loadPartialConfigAsync(...args),
+    loadPartialConfig: jest.fn<typeof actual.loadPartialConfig>((...args) =>
+      actual.loadPartialConfig(...args),
+    ),
+    loadPartialConfigAsync: jest.fn<typeof actual.loadPartialConfigAsync>(
+      (...args) => actual.loadPartialConfigAsync(...args),
     ),
   };
 });
@@ -69,7 +72,7 @@ test('Returns source string with inline maps when no transformOptions is passed'
 });
 
 test('Returns source string with inline maps when no transformOptions is passed async', async () => {
-  const result: any = await defaultBabelJestTransformer.processAsync!(
+  const result = await defaultBabelJestTransformer.processAsync!(
     sourceString,
     'dummy_path.js',
     {
@@ -86,8 +89,18 @@ test('Returns source string with inline maps when no transformOptions is passed
   expect(result.map).toBeDefined();
   expect(result.code).toMatch('//# sourceMappingURL');
   expect(result.code).toMatch('customMultiply');
-  expect(result.map!.sources).toEqual(['dummy_path.js']);
-  expect(JSON.stringify(result.map!.sourcesContent)).toMatch('customMultiply');
+
+  const {map} = result;
+
+  expect(map).toBeTruthy();
+  expect(typeof map).not.toBe('string');
+
+  if (map == null || typeof map === 'string') {
+    throw new Error('dead code');
+  }
+
+  expect(map.sources).toEqual(['dummy_path.js']);
+  expect(JSON.stringify(map.sourcesContent)).toMatch('customMultiply');
 });
 
 describe('caller option correctly merges from defaults and options', () => {

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

@@ -114,10 +114,10 @@ const IDVisitor = {
   ],
 };
 
-const FUNCTIONS: Record<
+const FUNCTIONS = Object.create(null) as Record<
   string,
   <T extends Node>(args: Array<NodePath<T>>) => boolean
-> = Object.create(null);
+>;
 
 FUNCTIONS.mock = args => {
   if (args.length === 1) {

packages/diff-sequences/src/__tests__/index.test.ts

@@ -15,7 +15,8 @@ describe('invalid arg', () => {
   describe('length', () => {
     test('is not a number', () => {
       expect(() => {
-        diff('0' as any, 0, isCommon, foundSubsequence);
+        // @ts-expect-error: Testing runtime errors here
+        diff('0', 0, isCommon, foundSubsequence);
       }).toThrow(/aLength/);
     });
     test('Infinity is not a safe integer', () => {
@@ -49,12 +50,14 @@ describe('invalid arg', () => {
   describe('callback', () => {
     test('null is not a function', () => {
       expect(() => {
-        diff(0, 0, null as any, foundSubsequence);
+        // @ts-expect-error: Testing runtime errors here
+        diff(0, 0, null, foundSubsequence);
       }).toThrow(/isCommon/);
     });
     test('undefined is not a function', () => {
       expect(() => {
-        diff(0, 0, isCommon, undefined as any);
+        // @ts-expect-error: Testing runtime errors here
+        diff(0, 0, isCommon, undefined);
       }).toThrow(/foundSubsequence/);
     });
   });

packages/expect/src/index.ts

@@ -39,7 +39,6 @@ import toThrowMatchers, {
   createMatcher as createThrowMatcher,
 } from './toThrowMatchers';
 import type {
-  AsyncExpectationResult,
   Expect,
   ExpectationResult,
   MatcherContext,
@@ -363,19 +362,16 @@ const makeThrowingMatcher = (
             })();
 
       if (isPromise(potentialResult)) {
-        const asyncResult = potentialResult as AsyncExpectationResult;
         const asyncError = new JestAssertionError();
         if (Error.captureStackTrace) {
           Error.captureStackTrace(asyncError, throwingMatcher);
         }
 
-        return asyncResult
+        return potentialResult
           .then(aResult => processResult(aResult, asyncError))
           .catch(handleError);
       } else {
-        const syncResult = potentialResult as SyncExpectationResult;
-
-        return processResult(syncResult);
+        return processResult(potentialResult);
       }
     } catch (error: any) {
       return handleError(error);

packages/jest-source-map/src/getCallsite.ts

@@ -15,15 +15,15 @@ const addSourceMapConsumer = (
   callsite: callsites.CallSite,
   tracer: TraceMap,
 ) => {
-  const getLineNumber = callsite.getLineNumber;
-  const getColumnNumber = callsite.getColumnNumber;
+  const getLineNumber = callsite.getLineNumber.bind(callsite);
+  const getColumnNumber = callsite.getColumnNumber.bind(callsite);
   let position: ReturnType<typeof originalPositionFor> | null = null;
 
   function getPosition() {
     if (!position) {
       position = originalPositionFor(tracer, {
-        column: getColumnNumber.call(callsite) || -1,
-        line: getLineNumber.call(callsite) || -1,
+        column: getColumnNumber() || -1,
+        line: getLineNumber() || -1,
       });
     }
 

scripts/buildTs.mjs

@@ -14,13 +14,9 @@ import globby from 'globby';
 import fs from 'graceful-fs';
 import pLimit from 'p-limit';
 import stripJsonComments from 'strip-json-comments';
-import {getPackages} from './buildUtils.mjs';
+import {getPackagesWithTsConfig} from './buildUtils.mjs';
 
-const packages = getPackages();
-
-const packagesWithTs = packages.filter(p =>
-  fs.existsSync(path.resolve(p.packageDir, 'tsconfig.json')),
-);
+const packagesWithTs = getPackagesWithTsConfig();
 
 const {stdout: allWorkspacesString} = await execa('yarn', [
   'workspaces',

scripts/buildUtils.mjs

@@ -121,3 +121,9 @@ export function adjustToTerminalWidth(str) {
   }
   return strs.slice(0, -1).concat(lastString).join('\n');
 }
+
+export function getPackagesWithTsConfig() {
+  return getPackages().filter(p =>
+    fs.existsSync(path.resolve(p.packageDir, 'tsconfig.json')),
+  );
+}

scripts/lintTs.mjs

@@ -0,0 +1,97 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+import * as os from 'os';
+import * as path from 'path';
+import * as url from 'url';
+import chalk from 'chalk';
+import {ESLint} from 'eslint';
+import pLimit from 'p-limit';
+import {getPackagesWithTsConfig} from './buildUtils.mjs';
+
+// we want to limit the number of processes we spawn
+const cpus = Math.max(1, os.cpus().length - 1);
+const mutex = pLimit(cpus);
+
+const fix = process.argv.slice(2).some(arg => arg === '--fix');
+
+const monorepoRoot = path.resolve(url.fileURLToPath(import.meta.url), '../..');
+
+// TODO: remove this list at some point and run against all packages
+const packagesToTest = [
+  'babel-jest',
+  'babel-plugin-jest-hoist',
+  'diff-sequences',
+  'jest-source-map',
+];
+
+const packagesWithTs = getPackagesWithTsConfig()
+  .map(({packageDir}) => packageDir)
+  .concat(path.resolve(monorepoRoot, 'e2e'))
+  .filter(packageDir => packagesToTest.some(pkg => packageDir.endsWith(pkg)));
+
+try {
+  await Promise.all(
+    packagesWithTs.map(packageDir =>
+      mutex(async () => {
+        const eslint = new ESLint({
+          cache: true,
+          cacheLocation: path.resolve(packageDir, '.eslintcache'),
+          cwd: monorepoRoot,
+          extensions: ['.ts'],
+          fix,
+          overrideConfig: {
+            extends: [
+              'plugin:@typescript-eslint/recommended-requiring-type-checking',
+            ],
+            parser: '@typescript-eslint/parser',
+            parserOptions: {
+              project: ['./tsconfig.json', `${packageDir}/tsconfig.json`],
+              tsconfigRootDir: monorepoRoot,
+            },
+            plugins: ['@typescript-eslint'],
+            root: true,
+          },
+        });
+
+        const filesToLint = packageDir.endsWith('e2e')
+          ? `${packageDir}/__tests__/`
+          : `${packageDir}/src/`;
+
+        let results = await eslint.lintFiles(filesToLint);
+
+        if (fix) {
+          await ESLint.outputFixes(results);
+
+          // re-run after outputting fixes
+          results = await eslint.lintFiles(filesToLint);
+        }
+
+        const filteredResults = ESLint.getErrorResults(results);
+
+        if (filteredResults.length > 0) {
+          const formatter = await eslint.loadFormatter('stylish');
+          const resultText = formatter.format(results);
+
+          console.error(resultText);
+
+          throw new Error('Got lint errors');
+        }
+      }),
+    ),
+  );
+} catch (e) {
+  console.error(
+    chalk.inverse.red(' Unable to lint using TypeScript info files '),
+  );
+
+  throw e;
+}
+
+console.log(
+  chalk.inverse.green(' Successfully linted using TypeScript info files '),
+);