feat(compiler): support ESM for isolatedModules: false

e2e/test-app-v10/jest-esm-uniso.config.js

@@ -0,0 +1,20 @@
+require('jest-preset-angular/ngcc-jest-processor');
+const baseConfig = require('./jest.config');
+
+/** @type {import('ts-jest/dist/types').ProjectConfigTsJest} */
+module.exports = {
+  ...baseConfig,
+  extensionsToTreatAsEsm: ['.ts'],
+  globals: {
+    'ts-jest': {
+      tsconfig: '<rootDir>/tsconfig-esm.spec.json',
+      stringifyContentPathRegex: '\\.html$',
+      useESM: true,
+    }
+  },
+  moduleNameMapper: {
+    ...baseConfig.moduleNameMapper,
+    'tslib': '<rootDir>/node_modules/tslib/tslib.es6.js',
+  },
+  transformIgnorePatterns: ['node_modules/(?!tslib)'],
+};

e2e/test-app-v10/package.json

@@ -8,6 +8,7 @@
     "test-cjs-uniso": "jest --clearCache && jest -c=jest-cjs-uniso.config.js",
     "test-cjs-iso": "jest --clearCache && jest -c=jest-cjs-iso.config.js",
     "test-esm-iso": "jest --clearCache && node --experimental-vm-modules ./node_modules/jest/bin/jest.js -c=jest-esm-iso.config.js",
+    "test-esm-uniso": "jest --clearCache && node --experimental-vm-modules ./node_modules/jest/bin/jest.js -c=jest-esm-uniso.config.js",
     "lint": "ng lint"
   },
   "private": true,

e2e/test-app-v11/jest-esm-uniso.config.js

@@ -0,0 +1,20 @@
+require('jest-preset-angular/ngcc-jest-processor');
+const baseConfig = require('./jest.config');
+
+/** @type {import('ts-jest/dist/types').ProjectConfigTsJest} */
+module.exports = {
+  ...baseConfig,
+  extensionsToTreatAsEsm: ['.ts'],
+  globals: {
+    'ts-jest': {
+      tsconfig: '<rootDir>/tsconfig-esm.spec.json',
+      stringifyContentPathRegex: '\\.html$',
+      useESM: true,
+    }
+  },
+  moduleNameMapper: {
+    ...baseConfig.moduleNameMapper,
+    'tslib': '<rootDir>/node_modules/tslib/tslib.es6.js',
+  },
+  transformIgnorePatterns: ['node_modules/(?!tslib)'],
+};

e2e/test-app-v11/package.json

@@ -8,6 +8,7 @@
     "test-cjs-uniso": "jest --clearCache && jest -c=jest-cjs-uniso.config.js",
     "test-cjs-iso": "jest --clearCache && jest -c=jest-cjs-iso.config.js",
     "test-esm-iso": "jest --clearCache && node --experimental-vm-modules ./node_modules/jest/bin/jest.js -c=jest-esm-iso.config.js",
+    "test-esm-uniso": "jest --clearCache && node --experimental-vm-modules ./node_modules/jest/bin/jest.js -c=jest-esm-uniso.config.js",
     "lint": "ng lint"
   },
   "private": true,

e2e/test-app-v9/jest-esm-uniso.config.js

@@ -0,0 +1,20 @@
+require('jest-preset-angular/ngcc-jest-processor');
+const baseConfig = require('./jest.config');
+
+/** @type {import('ts-jest/dist/types').ProjectConfigTsJest} */
+module.exports = {
+  ...baseConfig,
+  extensionsToTreatAsEsm: ['.ts'],
+  globals: {
+    'ts-jest': {
+      tsconfig: '<rootDir>/tsconfig-esm.spec.json',
+      stringifyContentPathRegex: '\\.html$',
+      useESM: true,
+    }
+  },
+  moduleNameMapper: {
+    ...baseConfig.moduleNameMapper,
+    'tslib': '<rootDir>/node_modules/tslib/tslib.es6.js',
+  },
+  transformIgnorePatterns: ['node_modules/(?!tslib)'],
+};

e2e/test-app-v9/package.json

@@ -8,6 +8,7 @@
     "test-cjs-uniso": "jest --clearCache && jest -c=jest-cjs-uniso.config.js",
     "test-cjs-iso": "jest --clearCache && jest -c=jest-cjs-iso.config.js",
     "test-esm-iso": "jest --clearCache && node --experimental-vm-modules ./node_modules/jest/bin/jest.js -c=jest-esm-iso.config.js",
+    "test-esm-uniso": "jest --clearCache && node --experimental-vm-modules ./node_modules/jest/bin/jest.js -c=jest-esm-uniso.config.js",
     "lint": "ng lint"
   },
   "private": true,

scripts/e2e.js

@@ -57,13 +57,16 @@ const executeTest = (projectRealPath) => {
   const cmdCjsUnIso = ['yarn', 'test-cjs-uniso'];
   const cmdCjsIso = ['yarn', 'test-cjs-iso'];
   const cmdESMIso = ['yarn', 'test-esm-iso'];
+  const cmdESMUnIso = ['yarn', 'test-esm-uniso'];
   if (jestArgs.length) {
     cmdCjsUnIso.push('--');
     cmdCjsIso.push('--');
     cmdESMIso.push('--');
+    cmdESMUnIso.push('--');
     cmdCjsUnIso.push(...jestArgs);
     cmdCjsIso.push(...jestArgs);
     cmdESMIso.push(...jestArgs);
+    cmdESMUnIso.push(...jestArgs);
   }
 
   logger.log('STARTING NONE ISOLATED MODULES TESTS');
@@ -77,6 +80,16 @@ const executeTest = (projectRealPath) => {
     env: process.env,
   });
 
+  logger.log();
+  logger.log('starting the ESM tests using:', ...cmdESMUnIso);
+  logger.log();
+
+  execa.sync(cmdESMUnIso.shift(), cmdESMUnIso, {
+    cwd: projectRealPath,
+    stdio: 'inherit',
+    env: process.env,
+  });
+
   logger.log();
   logger.log('STARTING ISOLATED MODULES TESTS');
   logger.log();

src/__tests__/__snapshots__/ng-jest-compiler.spec.ts.snap

@@ -1,5 +1,25 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`NgJestCompiler with isolatedModule false should compile codes with useESM true 1`] = `
+"import { __decorate } from \\"tslib\\";
+import __NG_CLI_RESOURCE__0 from \\"./app.component.html\\";
+import { Component } from '@angular/core';
+let AppComponent = class AppComponent {
+    constructor() {
+        this.title = 'test-app-v10';
+    }
+};
+AppComponent = __decorate([
+    Component({
+        selector: 'app-root',
+        template: __NG_CLI_RESOURCE__0,
+        styles: []
+    })
+], AppComponent);
+export { AppComponent };
+//# "
+`;
+
 exports[`NgJestCompiler with isolatedModule false should throw diagnostics error for new file which is: known by Program 1`] = `"src/__tests__/__mocks__/foo.component.ts(8,3): error TS2322: Type '\\"test-app-v10\\"' is not assignable to type 'number'."`;
 
 exports[`NgJestCompiler with isolatedModule false should throw diagnostics error for new file which is: not known by Program 1`] = `"src/__tests__/__mocks__/foo.component.ts(8,3): error TS2322: Type '\\"test-app-v10\\"' is not assignable to type 'number'."`;

src/__tests__/__snapshots__/replace-resources.spec.ts.snap

@@ -23,24 +23,22 @@ exports.AppComponent = AppComponent;
 `;
 
 exports[`Replace resources transformer with isolatedModules false should use replaceResources transformer from @angular/compiler-cli with useESM true 1`] = `
-"\\"use strict\\";
-Object.defineProperty(exports, \\"__esModule\\", { value: true });
-exports.AppComponent = void 0;
-const tslib_1 = require(\\"tslib\\");
-const core_1 = require(\\"@angular/core\\");
+"import { __decorate } from \\"tslib\\";
+import __NG_CLI_RESOURCE__0 from \\"./app.component.html\\";
+import { Component } from '@angular/core';
 let AppComponent = class AppComponent {
     constructor() {
         this.title = 'test-app-v10';
     }
 };
-AppComponent = tslib_1.__decorate([
-    core_1.Component({
+AppComponent = __decorate([
+    Component({
         selector: 'app-root',
-        template: require(\\"./app.component.html\\"),
+        template: __NG_CLI_RESOURCE__0,
         styles: []
     })
 ], AppComponent);
-exports.AppComponent = AppComponent;
+export { AppComponent };
 //# "
 `;
 

src/__tests__/ng-jest-compiler.spec.ts

@@ -2,6 +2,7 @@ import { readFileSync } from 'fs';
 import { join } from 'path';
 
 import { jest } from '@jest/globals';
+import { SOURCE_MAPPING_PREFIX } from 'ts-jest/dist/compiler/compiler-utils';
 import ts from 'typescript';
 
 import { NgJestCompiler } from '../compiler/ng-jest-compiler';
@@ -50,10 +51,15 @@ describe('NgJestCompiler', () => {
       // @ts-expect-error testing purpose
       expect(compiler._transpileModule).toHaveBeenCalled();
       // @ts-expect-error testing purpose
-      const moduleKind = compiler._transpileModule.mock.calls[0][1].compilerOptions.module;
-      useESM
-        ? expect(moduleKind).not.toEqual(ts.ModuleKind.CommonJS)
-        : expect(moduleKind).toEqual(ts.ModuleKind.CommonJS);
+      const { module, esModuleInterop, allowSyntheticDefaultImports } = compiler._transpileModule.mock.calls[0][1]
+        .compilerOptions as ts.CompilerOptions;
+      if (useESM) {
+        expect(module).not.toEqual(ts.ModuleKind.CommonJS);
+        expect(allowSyntheticDefaultImports).toEqual(true);
+        expect(esModuleInterop).toEqual(true);
+      } else {
+        expect(module).toEqual(ts.ModuleKind.CommonJS);
+      }
     });
   });
 
@@ -81,7 +87,6 @@ describe('NgJestCompiler', () => {
       'exports.AppComponent = AppComponent;\n' +
       '//# sourceMappingURL=app.component.js.map\n';
 
-    const ngJestConfig = new NgJestConfig(jestCfgStub);
     const noErrorFileName = join(mockFolder, 'app.component.ts');
     const noErrorFileContent = readFileSync(noErrorFileName, 'utf-8');
     const hasErrorFileName = join(mockFolder, 'foo.component.ts');
@@ -90,6 +95,7 @@ describe('NgJestCompiler', () => {
     test.each([noErrorFileName, undefined])(
       'should return compiled result for new file which is not known or known by Program',
       (fileName) => {
+        const ngJestConfig = new NgJestConfig(jestCfgStub);
         ngJestConfig.parsedTsConfig = {
           ...ngJestConfig.parsedTsConfig,
           rootNames: fileName ? [fileName] : [],
@@ -107,7 +113,28 @@ describe('NgJestCompiler', () => {
       },
     );
 
+    test('should compile codes with useESM true', () => {
+      const ngJestConfig = new NgJestConfig({
+        ...jestCfgStub,
+        globals: {
+          // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
+          'ts-jest': {
+            ...jestCfgStub.globals['ts-jest'],
+            useESM: true,
+          },
+        },
+      });
+      const compiler = new NgJestCompiler(ngJestConfig, new Map());
+
+      // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+      const emittedResult = compiler.getCompiledOutput(noErrorFileName, noErrorFileContent, true)!;
+
+      // Source map is different based on file location which can fail on CI, so we only compare snapshot for js
+      expect(emittedResult.substring(0, emittedResult.indexOf(SOURCE_MAPPING_PREFIX))).toMatchSnapshot();
+    });
+
     test.each([hasErrorFileName, undefined])('should throw diagnostics error for new file which is', (fileName) => {
+      const ngJestConfig = new NgJestConfig(jestCfgStub);
       ngJestConfig.parsedTsConfig = {
         ...ngJestConfig.parsedTsConfig,
         rootNames: fileName ? [fileName] : [],
@@ -120,6 +147,7 @@ describe('NgJestCompiler', () => {
     });
 
     test('should not throw diagnostics error when shouldReportDiagnostics return false', () => {
+      const ngJestConfig = new NgJestConfig(jestCfgStub);
       ngJestConfig.parsedTsConfig = {
         ...ngJestConfig.parsedTsConfig,
         rootNames: [hasErrorFileName],

src/compiler/ng-jest-compiler.ts

@@ -46,8 +46,30 @@ export class NgJestCompiler implements CompilerInstance {
 
   getCompiledOutput(fileName: string, fileContent: string, supportsStaticESM: boolean): string {
     const customTransformers = this.ngJestConfig.customTransformers;
+    let moduleKind = this._compilerOptions.module;
+    let esModuleInterop = this._compilerOptions.esModuleInterop;
+    let allowSyntheticDefaultImports = this._compilerOptions.allowSyntheticDefaultImports;
+    if (supportsStaticESM && this.ngJestConfig.useESM) {
+      moduleKind =
+        !moduleKind ||
+        (moduleKind &&
+          ![this._ts.ModuleKind.ES2015, this._ts.ModuleKind.ES2020, this._ts.ModuleKind.ESNext].includes(moduleKind))
+          ? this._ts.ModuleKind.ESNext
+          : moduleKind;
+      // Make sure `esModuleInterop` and `allowSyntheticDefaultImports` true to support import CJS into ESM
+      esModuleInterop = true;
+      allowSyntheticDefaultImports = true;
+    } else {
+      moduleKind = this._ts.ModuleKind.CommonJS;
+    }
+    this._compilerOptions = {
+      ...this._compilerOptions,
+      allowSyntheticDefaultImports,
+      esModuleInterop,
+      module: moduleKind,
+    };
     if (this._program) {
-      const allDiagnostics = [];
+      const allDiagnostics: ts.Diagnostic[] = [];
       if (!this._rootNames.includes(fileName)) {
         this._logger.debug({ fileName }, 'getCompiledOutput: update memory host, rootFiles and Program');
 
@@ -95,28 +117,13 @@ export class NgJestCompiler implements CompilerInstance {
         return '';
       }
     } else {
-      let moduleKind = this._compilerOptions.module;
-      if (supportsStaticESM && this.ngJestConfig.useESM) {
-        moduleKind =
-          !moduleKind ||
-          (moduleKind &&
-            ![this._ts.ModuleKind.ES2015, this._ts.ModuleKind.ES2020, this._ts.ModuleKind.ESNext].includes(moduleKind))
-            ? this._ts.ModuleKind.ESNext
-            : moduleKind;
-      } else {
-        moduleKind = this._ts.ModuleKind.CommonJS;
-      }
-
       this._logger.debug({ fileName }, 'getCompiledOutput: compiling as isolated module');
 
       const result: ts.TranspileOutput = this._transpileModule(
         fileContent,
         {
           fileName,
-          compilerOptions: {
-            ...this._compilerOptions,
-            module: moduleKind,
-          },
+          compilerOptions: this._compilerOptions,
         },
         customTransformers,
       );