fix: vm.script code coverage had been tampered (#10645)

CHANGELOG.md

@@ -24,6 +24,7 @@
 - `[jest-config]` Simplify transform RegExp ([#10207](https://github.com/facebook/jest/pull/10207))
 - `[jest-fake-timers]` Lazily instantiate mock timers ([#10551](https://github.com/facebook/jest/pull/10551))
 - `[jest-runtime]` `require.main` is no longer `undefined` when using `jest.resetModules` ([#10626](https://github.com/facebook/jest/pull/10626))
+- `[jest-runtime]` Keep the original appearance in the vm.script code-coverage. ([#10645](https://github.com/facebook/jest/pull/10645))
 - `[@jest/types]` Add missing values for `timers` ([#10632](https://github.com/facebook/jest/pull/10632))
 
 ### Chore & Maintenance

e2e/__tests__/__snapshots__/v8Coverage.test.ts.snap

@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`on node >=10 prints coverage 1`] = `
+exports[`prints coverage 1`] = `
 "  console.log
     42
 
@@ -14,3 +14,12 @@ All files |     100 |      100 |     100 |     100 |
  x.css    |     100 |      100 |     100 |     100 |                   
 ----------|---------|----------|---------|---------|-------------------"
 `;
+
+exports[`vm script coverage generater 1`] = `
+"-------------|---------|----------|---------|---------|-------------------
+File         | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
+-------------|---------|----------|---------|---------|-------------------
+All files    |     100 |      100 |     100 |     100 |                   
+ vmscript.js |     100 |      100 |     100 |     100 |                   
+-------------|---------|----------|---------|---------|-------------------"
+`;

e2e/__tests__/v8Coverage.test.ts

@@ -6,24 +6,33 @@
  */
 
 import * as path from 'path';
-import {onNodeVersions} from '@jest/test-utils';
 import runJest from '../runJest';
+import {runYarn} from '../Utils';
 
 const DIR = path.resolve(__dirname, '../v8-coverage');
 
-onNodeVersions('>=10', () => {
-  test('prints coverage', () => {
-    const sourcemapDir = path.join(DIR, 'no-sourcemap');
+test('prints coverage', () => {
+  const sourcemapDir = path.join(DIR, 'no-sourcemap');
 
-    const {stdout, exitCode} = runJest(
-      sourcemapDir,
-      ['--coverage', '--coverage-provider', 'v8'],
-      {
-        stripAnsi: true,
-      },
-    );
+  const {stdout, exitCode} = runJest(
+    sourcemapDir,
+    ['--coverage', '--coverage-provider', 'v8'],
+    {stripAnsi: true},
+  );
 
-    expect(exitCode).toBe(0);
-    expect(stdout).toMatchSnapshot();
-  });
+  expect(exitCode).toBe(0);
+  expect(stdout).toMatchSnapshot();
+});
+
+test('vm script coverage generater', () => {
+  const dir = path.resolve(__dirname, '../vmscript-coverage');
+  runYarn(dir);
+  const {stdout, exitCode} = runJest(
+    dir,
+    ['--coverage', '--coverage-provider', 'v8'],
+    {stripAnsi: true},
+  );
+
+  expect(exitCode).toBe(0);
+  expect(stdout).toMatchSnapshot();
 });

e2e/v8-coverage/no-sourcemap/package.json

@@ -4,8 +4,7 @@
   "jest": {
     "testEnvironment": "node",
     "transform": {
-      "\\.[jt]sx?$": "babel-jest",
-      "\\.css$": "<rootDir>/cssTransform.js"
+      "\\.[jt]sx?$": "babel-jest"
     }
   }
 }

e2e/vmscript-coverage/__tests__/extract-coverage.test.js

@@ -0,0 +1,42 @@
+/**
+ * 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.
+ */
+
+const vm = require('vm');
+const path = require('path');
+const fs = require('fs');
+const filePath = path.resolve(__dirname, '../package/vmscript.js');
+
+test('extract coverage', () => {
+  const content = fs.readFileSync(filePath, {encoding: 'utf8'});
+
+  const case1 = vm.runInNewContext(
+    content,
+    {
+      inputObject: {
+        number: 0,
+      },
+    },
+    {
+      filename: filePath,
+    },
+  );
+
+  const case2 = vm.runInNewContext(
+    content,
+    {
+      inputObject: {
+        number: 7,
+      },
+    },
+    {
+      filename: filePath,
+    },
+  );
+
+  expect(case1).toBe(false);
+  expect(case2).toBe(true);
+});

e2e/vmscript-coverage/package.json

@@ -0,0 +1,6 @@
+{
+  "jest": {
+    "rootDir": "./",
+    "testEnvironment": "node"
+  }
+}

e2e/vmscript-coverage/package/vmscript.js

@@ -0,0 +1,23 @@
+/**
+ * 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.
+ */
+
+function addOne(inputNumber) {
+  return ++inputNumber;
+}
+
+function isEven(inputNumber) {
+  if (inputNumber % 2 === 0) {
+    return true;
+  } else {
+    return false;
+  }
+}
+
+/* global inputObject */
+if (inputObject.number / 1 === inputObject.number) {
+  isEven(addOne(inputObject.number));
+}

e2e/vmscript-coverage/yarn.lock

@@ -0,0 +1,11 @@
+# This file is generated by running "yarn install" inside your project.
+# Manual changes might be lost - proceed with caution!
+
+__metadata:
+  version: 4
+
+"root-workspace-0b6124@workspace:.":
+  version: 0.0.0-use.local
+  resolution: "root-workspace-0b6124@workspace:."
+  languageName: unknown
+  linkType: soft

packages/jest-runtime/src/index.ts

@@ -827,7 +827,6 @@ class Runtime {
         res =>
           // TODO: will this work on windows? It might be better if `shouldInstrument` deals with it anyways
           res.url.startsWith(this._config.rootDir) &&
-          this._fileTransforms.has(res.url) &&
           shouldInstrument(res.url, this._coverageOptions, this._config),
       )
       .map(result => {