fix(jest-config): allow collectCoverage to be configured at project level

CHANGELOG.md

@@ -7,6 +7,7 @@
 ### Fixes
 
 - `[jest-runtime]` Fix issue where user cannot utilize dynamic import despite specifying `--experimental-vm-modules` Node option ([#15842](https://github.com/jestjs/jest/pull/15842))
+- `[jest-config]` Fix issue where user cannot toggle `collectCoverage` at project level ([#15588](https://github.com/jestjs/jest/issues/15588))
 - `[jest-test-sequencer]` Fix issue where failed tests due to compilation errors not getting re-executed even with `--onlyFailures` CLI option ([#15851](https://github.com/jestjs/jest/pull/15851))
 
 ### Chore & Maintenance

e2e/__tests__/__snapshots__/coverageReportForMultiProjects.test.ts.snap

@@ -0,0 +1,13 @@
+// Jest Snapshot v1, https://jestjs.io/docs/snapshot-testing
+
+exports[`exclude a project's code coverage if its collectCoverage is toggled off 1`] = `
+"-----------|---------|----------|---------|---------|-------------------
+File       | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
+-----------|---------|----------|---------|---------|-------------------
+All files  |     100 |      100 |     100 |     100 |                   
+ package-1 |     100 |      100 |     100 |     100 |                   
+  index.js |     100 |      100 |     100 |     100 |                   
+ package-2 |     100 |      100 |     100 |     100 |                   
+  index.js |     100 |      100 |     100 |     100 |                   
+-----------|---------|----------|---------|---------|-------------------"
+`;

e2e/__tests__/__snapshots__/showConfig.test.ts.snap

@@ -105,7 +105,6 @@ exports[`--showConfig outputs config info and exits 1`] = `
     "bail": 0,
     "changedFilesWithAncestor": false,
     "ci": true,
-    "collectCoverage": false,
     "collectCoverageFrom": [],
     "coverageDirectory": "<<REPLACED_ROOT_DIR>>/coverage",
     "coverageProvider": "babel",

e2e/__tests__/coverageReportForMultiProjects.test.ts

@@ -0,0 +1,17 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+import * as path from 'path';
+import runJest from '../runJest';
+
+const DIR = path.resolve(__dirname, '../coverage-report-for-multi-projects');
+
+test("exclude a project's code coverage if its collectCoverage is toggled off", () => {
+  const {stdout, exitCode} = runJest(DIR, ['--no-cache']);
+  expect(stdout).toMatchSnapshot();
+  expect(exitCode).toBe(0);
+});

e2e/coverage-report-for-multi-projects/jest.config.js

@@ -0,0 +1,31 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+export default {
+  clearMocks: true,
+  collectCoverage: true,
+  collectCoverageFrom: ['./**/index.js', '!./__tests__/**/*.js'],
+  coverageProvider: 'v8',
+  projects: [
+    {
+      displayName: 'Package 1',
+      rootDir: '<rootDir>/packages/package-1',
+      testMatch: ['<rootDir>/__tests__/**/*.e2e.js'],
+    },
+    {
+      displayName: 'Package 2',
+      rootDir: '<rootDir>/packages/package-2',
+      testMatch: ['<rootDir>/__tests__/**/*.e2e.js'],
+    },
+    {
+      collectCoverage: false,
+      displayName: 'Package 3',
+      rootDir: '<rootDir>/packages/package-3',
+      testMatch: ['<rootDir>/__tests__/**/*.e2e.js'],
+    },
+  ],
+};

e2e/coverage-report-for-multi-projects/package.json

@@ -0,0 +1,6 @@
+{
+  "type": "module",
+  "workspaces": [
+    "packages/*"
+  ]
+}

e2e/coverage-report-for-multi-projects/packages/package-1/__tests__/example.e2e.js

@@ -0,0 +1,15 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+'use strict';
+
+const {package1} = require('../index.js');
+
+describe('Example Package 1 Test', () => {
+  it('should run', () => {
+    expect(package1()).toBeTruthy();
+  });
+});

e2e/coverage-report-for-multi-projects/packages/package-1/index.js

@@ -0,0 +1,11 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+'use strict';
+
+module.exports = {
+  package1: () => true,
+};

e2e/coverage-report-for-multi-projects/packages/package-2/__tests__/example.e2e.js

@@ -0,0 +1,15 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+'use strict';
+
+const {package2} = require('../index');
+
+describe('Example Package 2 Test', () => {
+  it('should run', () => {
+    expect(package2()).toBeTruthy();
+  });
+});

e2e/coverage-report-for-multi-projects/packages/package-2/index.js

@@ -0,0 +1,11 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+'use strict';
+
+module.exports = {
+  package2: () => true,
+};

e2e/coverage-report-for-multi-projects/packages/package-3/__tests__/example.e2e.js

@@ -0,0 +1,13 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+'use strict';
+
+describe('Example Package 3 Test', () => {
+  it('should run', () => {
+    expect(true).toBeTruthy();
+  });
+});

e2e/coverage-report-for-multi-projects/packages/package-3/index.js

@@ -0,0 +1,11 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+'use strict';
+
+module.exports = {
+  package3: () => true,
+};

packages/jest-config/src/ValidConfig.ts

@@ -208,6 +208,7 @@ export const initialProjectOptions: Config.InitialProjectOptions = {
   cache: true,
   cacheDirectory: '/tmp/user/jest',
   clearMocks: false,
+  collectCoverage: false,
   collectCoverageFrom: ['src', '!public'],
   coverageDirectory: 'coverage',
   coveragePathIgnorePatterns: [NODE_MODULES_REGEXP],

packages/jest-config/src/index.ts

@@ -197,6 +197,7 @@ const groupOptions = (
     cache: options.cache,
     cacheDirectory: options.cacheDirectory,
     clearMocks: options.clearMocks,
+    collectCoverage: options.collectCoverage,
     collectCoverageFrom: options.collectCoverageFrom,
     coverageDirectory: options.coverageDirectory,
     coveragePathIgnorePatterns: options.coveragePathIgnorePatterns,

packages/jest-config/src/normalize.ts

@@ -554,6 +554,9 @@ export default async function normalize(
   if (!options.coverageDirectory) {
     options.coverageDirectory = path.resolve(options.rootDir, 'coverage');
   }
+  if (!Object.hasOwn(options, 'collectCoverage')) {
+    options.collectCoverage = undefined;
+  }
 
   setupBabelJest(options);
   // TODO: Type this properly

packages/jest-transform/src/__tests__/ScriptTransformer.test.ts

@@ -314,6 +314,7 @@ describe('ScriptTransformer', () => {
     config = makeProjectConfig({
       cache: true,
       cacheDirectory: '/cache/',
+      collectCoverage: undefined,
       id: 'test',
       rootDir: '/',
       transformIgnorePatterns: ['/node_modules/'],

packages/jest-transform/src/__tests__/__snapshots__/ScriptTransformer.test.ts.snap

@@ -26,6 +26,7 @@ exports[`ScriptTransformer in async mode, passes expected transform options to g
           "cache": true,
           "cacheDirectory": "/cache/",
           "clearMocks": false,
+          "collectCoverage": undefined,
           "collectCoverageFrom": Array [
             "src",
             "!public",
@@ -177,6 +178,7 @@ exports[`ScriptTransformer passes expected transform options to getCacheKey 1`]
           "cache": true,
           "cacheDirectory": "/cache/",
           "clearMocks": false,
+          "collectCoverage": undefined,
           "collectCoverageFrom": Array [
             "src",
             "!public",
@@ -302,6 +304,7 @@ exports[`ScriptTransformer passes expected transform options to getCacheKeyAsync
           "cache": true,
           "cacheDirectory": "/cache/",
           "clearMocks": false,
+          "collectCoverage": undefined,
           "collectCoverageFrom": Array [
             "src",
             "!public",

packages/jest-transform/src/__tests__/shouldInstrument.test.ts

@@ -18,7 +18,10 @@ describe('shouldInstrument', () => {
     }),
     changedFiles: undefined,
   };
-  const defaultConfig = makeProjectConfig({rootDir: '/'});
+  const defaultConfig = makeProjectConfig({
+    collectCoverage: undefined,
+    rootDir: '/',
+  });
   describe('should return true', () => {
     const testShouldInstrument = (
       filename = defaultFilename,

packages/jest-transform/src/shouldInstrument.ts

@@ -36,7 +36,11 @@ export default function shouldInstrument(
   config: Config.ProjectConfig,
   loadedFilenames?: Array<string>,
 ): boolean {
-  if (!options.collectCoverage) {
+  // Do not instrument when `collectCoverage` is toggled off global or project-wide
+  if (
+    !options.collectCoverage ||
+    (typeof config.collectCoverage === 'boolean' && !config.collectCoverage)
+  ) {
     return false;
   }
 

packages/jest-types/src/Config.ts

@@ -331,6 +331,7 @@ export type ProjectConfig = {
   cache: boolean;
   cacheDirectory: string;
   clearMocks: boolean;
+  collectCoverage?: boolean;
   collectCoverageFrom: Array<string>;
   coverageDirectory: string;
   coveragePathIgnorePatterns: Array<string>;

packages/test-utils/src/config.ts

@@ -75,6 +75,7 @@ const DEFAULT_PROJECT_CONFIG: Config.ProjectConfig = {
   cache: false,
   cacheDirectory: '/test_cache_dir/',
   clearMocks: false,
+  collectCoverage: undefined,
   collectCoverageFrom: ['src', '!public'],
   coverageDirectory: 'coverage',
   coveragePathIgnorePatterns: [],