feat: pass ESM options to Babel (#9766)

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ### Features
 
+- `[babel-jest]` Support passing `supportsDynamicImport` and `supportsStaticESM` ([#9766](https://github.com/facebook/jest/pull/9766))
+
 ### Fixes
 
 ### Chore & Maintenance

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

@@ -6,7 +6,7 @@ FAIL __tests__/ignoredFile.test.js
 
     babel-jest: Babel ignores __tests__/ignoredFile.test.js - make sure to include the file in Jest's transformIgnorePatterns as well.
 
-      at loadBabelConfig (../../../packages/babel-jest/build/index.js:191:13)
+      at loadBabelConfig (../../../packages/babel-jest/build/index.js:227:13)
 `;
 
 exports[`babel-jest instruments only specific files and collects coverage 1`] = `

packages/babel-jest/package.json

@@ -20,7 +20,7 @@
   "dependencies": {
     "@jest/transform": "^25.2.6",
     "@jest/types": "^25.2.6",
-    "@types/babel__core": "^7.1.0",
+    "@types/babel__core": "^7.1.7",
     "babel-plugin-istanbul": "^6.0.0",
     "babel-preset-jest": "^25.2.6",
     "chalk": "^3.0.0",

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

@@ -5,9 +5,18 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import babelJest from '../index';
+import babelJest = require('../index');
+import {loadPartialConfig} from '../loadBabelConfig';
 import {makeProjectConfig} from '../../../../TestUtils';
 
+jest.mock('../loadBabelConfig', () => {
+  const actual = jest.requireActual('@babel/core');
+
+  return {
+    loadPartialConfig: jest.fn((...args) => actual.loadPartialConfig(...args)),
+  };
+});
+
 //Mock data for all the tests
 const sourceString = `
 const sum = (a, b) => a+b;
@@ -21,7 +30,11 @@ const customMultiply = (obj, mul) => {
 customMultiply({a: 32, dummy: "test"}, 2);
 `;
 
-test(`Returns source string with inline maps when no transformOptions is passed`, () => {
+beforeEach(() => {
+  jest.clearAllMocks();
+});
+
+test('Returns source string with inline maps when no transformOptions is passed', () => {
   const result = babelJest.process(
     sourceString,
     'dummy_path.js',
@@ -32,6 +45,55 @@ 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');
+  expect(result.map!.sources).toEqual(['dummy_path.js']);
+  expect(JSON.stringify(result.map!.sourcesContent)).toMatch('customMultiply');
+});
+
+describe('caller option correctly merges from defaults and options', () => {
+  test.each([
+    [
+      {
+        supportsDynamicImport: true,
+        supportsStaticESM: true,
+      },
+      {
+        supportsDynamicImport: true,
+        supportsStaticESM: true,
+      },
+    ],
+    [
+      {
+        supportsDynamicImport: false,
+        supportsStaticESM: false,
+      },
+      {
+        supportsDynamicImport: false,
+        supportsStaticESM: false,
+      },
+    ],
+    [
+      {supportsStaticESM: false},
+      {
+        supportsDynamicImport: false,
+        supportsStaticESM: false,
+      },
+    ],
+    [
+      {supportsDynamicImport: true},
+      {
+        supportsDynamicImport: true,
+        supportsStaticESM: false,
+      },
+    ],
+  ])('%j -> %j', (input, output) => {
+    babelJest.process(sourceString, 'dummy_path.js', makeProjectConfig(), {
+      instrument: false,
+      ...input,
+    });
+
+    expect(loadPartialConfig).toHaveBeenCalledTimes(1);
+    expect(loadPartialConfig).toHaveBeenCalledWith(
+      expect.objectContaining({caller: {name: 'babel-jest', ...output}}),
+    );
+  });
 });

packages/babel-jest/src/index.ts

@@ -8,14 +8,19 @@
 import {createHash} from 'crypto';
 import * as fs from 'fs';
 import * as path from 'path';
-import type {Transformer} from '@jest/transform';
+import type {
+  TransformOptions as JestTransformOptions,
+  Transformer,
+} from '@jest/transform';
 import type {Config} from '@jest/types';
 import {
   PartialConfig,
+  PluginItem,
+  TransformCaller,
   TransformOptions,
   transformSync as babelTransform,
-  loadPartialConfig,
 } from '@babel/core';
+import {loadPartialConfig} from './loadBabelConfig';
 import chalk = require('chalk');
 import slash = require('slash');
 
@@ -27,28 +32,51 @@ const babelIstanbulPlugin = require.resolve('babel-plugin-istanbul');
 interface BabelJestTransformer extends Transformer {
   canInstrument: true;
 }
+interface BabelJestTransformOptions extends TransformOptions {
+  caller: TransformCaller;
+  compact: false;
+  plugins: Array<PluginItem>;
+  presets: Array<PluginItem>;
+  sourceMaps: 'both';
+}
 
 const createTransformer = (
-  options: TransformOptions = {},
+  inputOptions: TransformOptions = {},
 ): BabelJestTransformer => {
-  options = {
-    ...options,
+  const options: BabelJestTransformOptions = {
+    ...inputOptions,
     caller: {
       name: 'babel-jest',
+      supportsDynamicImport: false,
       supportsStaticESM: false,
+      ...inputOptions.caller,
     },
     compact: false,
-    plugins: (options && options.plugins) || [],
-    presets: ((options && options.presets) || []).concat(jestPresetPath),
+    plugins: inputOptions.plugins ?? [],
+    presets: (inputOptions.presets ?? []).concat(jestPresetPath),
     sourceMaps: 'both',
   };
 
   function loadBabelConfig(
     cwd: Config.Path,
     filename: Config.Path,
+    transformOptions?: JestTransformOptions,
   ): PartialConfig {
     // `cwd` first to allow incoming options to override it
-    const babelConfig = loadPartialConfig({cwd, ...options, filename});
+    const babelConfig = loadPartialConfig({
+      cwd,
+      ...options,
+      caller: {
+        ...options.caller,
+        supportsDynamicImport:
+          transformOptions?.supportsDynamicImport ??
+          options.caller.supportsDynamicImport,
+        supportsStaticESM:
+          transformOptions?.supportsStaticESM ??
+          options.caller.supportsStaticESM,
+      },
+      filename,
+    });
 
     if (!babelConfig) {
       throw new Error(
@@ -65,13 +93,14 @@ const createTransformer = (
 
   return {
     canInstrument: true,
-    getCacheKey(
-      fileData,
-      filename,
-      configString,
-      {config, instrument, rootDir},
-    ) {
-      const babelOptions = loadBabelConfig(config.cwd, filename);
+    getCacheKey(fileData, filename, configString, cacheKeyOptions) {
+      const {config, instrument, rootDir} = cacheKeyOptions;
+
+      const babelOptions = loadBabelConfig(
+        config.cwd,
+        filename,
+        cacheKeyOptions,
+      );
       const configPath = [
         babelOptions.config || '',
         babelOptions.babelrc || '',
@@ -98,9 +127,11 @@ const createTransformer = (
         .digest('hex');
     },
     process(src, filename, config, transformOptions) {
-      const babelOptions = {...loadBabelConfig(config.cwd, filename).options};
+      const babelOptions = {
+        ...loadBabelConfig(config.cwd, filename, transformOptions).options,
+      };
 
-      if (transformOptions && transformOptions.instrument) {
+      if (transformOptions?.instrument) {
         babelOptions.auxiliaryCommentBefore = ' istanbul ignore next ';
         // Copied from jest-runtime transform.js
         babelOptions.plugins = (babelOptions.plugins || []).concat([

packages/babel-jest/src/loadBabelConfig.ts

@@ -0,0 +1,9 @@
+/**
+ * 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.
+ */
+
+// this is a separate file so it can be mocked in tests
+export {loadPartialConfig} from '@babel/core';

packages/jest-runtime/src/index.ts

@@ -497,11 +497,7 @@ class Runtime {
   ): TransformationOptions {
     return {
       ...options,
-      changedFiles: this._coverageOptions.changedFiles,
-      collectCoverage: this._coverageOptions.collectCoverage,
-      collectCoverageFrom: this._coverageOptions.collectCoverageFrom,
-      collectCoverageOnlyFrom: this._coverageOptions.collectCoverageOnlyFrom,
-      coverageProvider: this._coverageOptions.coverageProvider,
+      ...this._coverageOptions,
     };
   }
 

packages/jest-runtime/tsconfig.json

@@ -17,6 +17,7 @@
     {"path": "../jest-snapshot"},
     {"path": "../jest-source-map"},
     {"path": "../jest-test-result"},
+    {"path": "../jest-transform"},
     {"path": "../jest-types"},
     {"path": "../jest-util"},
     {"path": "../jest-validate"},

packages/jest-transform/src/ScriptTransformer.ts

@@ -101,6 +101,8 @@ export default class ScriptTransformer {
             config: this._config,
             instrument,
             rootDir: this._config.rootDir,
+            supportsDynamicImport: false,
+            supportsStaticESM: false,
           }),
         )
         .update(CACHE_VERSION)
@@ -285,6 +287,8 @@ export default class ScriptTransformer {
     if (transform && shouldCallTransform) {
       const processed = transform.process(content, filename, this._config, {
         instrument,
+        supportsDynamicImport: false,
+        supportsStaticESM: false,
       });
 
       if (typeof processed === 'string') {

packages/jest-transform/src/__tests__/__snapshots__/script_transformer.test.js.snap

@@ -71,6 +71,8 @@ Object {
   },
   "instrument": true,
   "rootDir": "/",
+  "supportsDynamicImport": false,
+  "supportsStaticESM": false,
 }
 `;
 

packages/jest-transform/src/index.ts

@@ -15,6 +15,7 @@ export type {
   Transformer,
   ShouldInstrumentOptions,
   Options as TransformationOptions,
+  TransformOptions,
   TransformResult,
   TransformedSource,
 } from './types';

packages/jest-transform/src/types.ts

@@ -22,6 +22,8 @@ export type Options = ShouldInstrumentOptions &
   Partial<{
     isCoreModule: boolean;
     isInternalModule: boolean;
+    supportsDynamicImport: boolean;
+    supportsStaticESM: boolean;
   }>;
 
 // extends directly after https://github.com/sandersn/downlevel-dts/issues/33 is fixed
@@ -38,15 +40,18 @@ export type TransformedSource =
 
 export type TransformResult = TransformTypes.TransformResult;
 
-export type TransformOptions = {
+export interface TransformOptions {
   instrument: boolean;
-};
+  // names are copied from babel
+  supportsDynamicImport?: boolean;
+  supportsStaticESM?: boolean;
+}
 
-export type CacheKeyOptions = {
+// TODO: For Jest 26 we should combine these into one options shape
+export interface CacheKeyOptions extends TransformOptions {
   config: Config.ProjectConfig;
-  instrument: boolean;
   rootDir: string;
-};
+}
 
 export interface Transformer {
   canInstrument?: boolean;

yarn.lock

@@ -2137,10 +2137,10 @@
   resolved "https://registry.yarnpkg.com/@types/babel__code-frame/-/babel__code-frame-7.0.1.tgz#baf2529c4abbfb5e4008c845efcfe39a187e2f99"
   integrity sha512-FFfbQozKxYmOnCKFYV+EQprjBI7u2yaNc2ly/K9AhzyC8MzXtCtSRqptpw+HUJxhwCOo5mLwf1ATmzyhOaVbDg==
 
-"@types/babel__core@^7.0.0", "@types/babel__core@^7.0.4", "@types/babel__core@^7.1.0":
-  version "7.1.6"
-  resolved "https://registry.yarnpkg.com/@types/babel__core/-/babel__core-7.1.6.tgz#16ff42a5ae203c9af1c6e190ed1f30f83207b610"
-  integrity sha512-tTnhWszAqvXnhW7m5jQU9PomXSiKXk2sFxpahXvI20SZKu9ylPi8WtIxueZ6ehDWikPT0jeFujMj3X4ZHuf3Tg==
+"@types/babel__core@^7.0.0", "@types/babel__core@^7.0.4", "@types/babel__core@^7.1.0", "@types/babel__core@^7.1.7":
+  version "7.1.7"
+  resolved "https://registry.yarnpkg.com/@types/babel__core/-/babel__core-7.1.7.tgz#1dacad8840364a57c98d0dd4855c6dd3752c6b89"
+  integrity sha512-RL62NqSFPCDK2FM1pSDH0scHpJvsXtZNiYlMB73DgPBaG1E38ZYVL+ei5EkWRbr+KC4YNiAUNBnRj+bgwpgjMw==
   dependencies:
     "@babel/parser" "^7.1.0"
     "@babel/types" "^7.0.0"