fix: revert commit ad7a297 to fix perf regression

As reported, the perf issue is caused by the introduction of an extra `Program` instance to fetch to AST transformers next to the hidden `Program` behind `ts.transpileModule`. We should only use one instance of `Program` therefore we have to manually copy the codes of `ts.transpileModule` to use for our case.

Fixes #2886

examples/example-app-monorepo/apps/app1/src/app/app.component.ts

@@ -1,4 +1,5 @@
-import { Component } from '@angular/core';
+import { DOCUMENT } from '@angular/common';
+import { Component, Inject } from '@angular/core';
 import { RouterLink, RouterOutlet } from '@angular/router';
 
 import { BannerComponent } from './banner/banner.component';
@@ -10,4 +11,8 @@ import { WelcomeComponent } from './welcome/welcome.component';
     templateUrl: './app.component.html',
     imports: [BannerComponent, WelcomeComponent, RouterOutlet, RouterLink],
 })
-export class AppComponent {}
+export class AppComponent {
+    constructor(@Inject(DOCUMENT) injectedDoc: Document) {
+        injectedDoc.title = 'Example App';
+    }
+}

examples/example-app-v17/src/app/app.component.ts

@@ -1,4 +1,5 @@
-import { Component } from '@angular/core';
+import { DOCUMENT } from '@angular/common';
+import { Component, Inject } from '@angular/core';
 import { RouterLink, RouterOutlet } from '@angular/router';
 
 import { BannerComponent } from './banner/banner.component';
@@ -10,4 +11,8 @@ import { WelcomeComponent } from './welcome/welcome.component';
     templateUrl: './app.component.html',
     imports: [BannerComponent, WelcomeComponent, RouterOutlet, RouterLink],
 })
-export class AppComponent {}
+export class AppComponent {
+    constructor(@Inject(DOCUMENT) injectedDoc: Document) {
+        injectedDoc.title = 'Example App';
+    }
+}

examples/example-app-v18/src/app/app.component.ts

@@ -1,4 +1,5 @@
-import { Component } from '@angular/core';
+import { DOCUMENT } from '@angular/common';
+import { Component, Inject } from '@angular/core';
 import { RouterLink, RouterOutlet } from '@angular/router';
 
 import { BannerComponent } from './banner/banner.component';
@@ -10,4 +11,8 @@ import { WelcomeComponent } from './welcome/welcome.component';
     templateUrl: './app.component.html',
     imports: [BannerComponent, WelcomeComponent, RouterOutlet, RouterLink],
 })
-export class AppComponent {}
+export class AppComponent {
+    constructor(@Inject(DOCUMENT) injectedDoc: Document) {
+        injectedDoc.title = 'Example App';
+    }
+}

examples/example-app-v19/src/app/app.component.ts

@@ -1,4 +1,5 @@
-import { Component } from '@angular/core';
+import { DOCUMENT } from '@angular/common';
+import { Component, Inject } from '@angular/core';
 import { RouterLink, RouterOutlet } from '@angular/router';
 
 import { BannerComponent } from './banner/banner.component';
@@ -9,4 +10,8 @@ import { WelcomeComponent } from './welcome/welcome.component';
     templateUrl: './app.component.html',
     imports: [BannerComponent, WelcomeComponent, RouterOutlet, RouterLink],
 })
-export class AppComponent {}
+export class AppComponent {
+    constructor(@Inject(DOCUMENT) injectedDoc: Document) {
+        injectedDoc.title = 'Example App';
+    }
+}

examples/example-app-yarn-workspace/packages/angular-app/src/app/app.component.ts

@@ -1,4 +1,5 @@
-import { Component } from '@angular/core';
+import { DOCUMENT } from '@angular/common';
+import { Component, Inject } from '@angular/core';
 import { RouterLink, RouterOutlet } from '@angular/router';
 
 import { BannerComponent } from './banner/banner.component';
@@ -10,4 +11,8 @@ import { WelcomeComponent } from './welcome/welcome.component';
     templateUrl: './app.component.html',
     imports: [BannerComponent, WelcomeComponent, RouterOutlet, RouterLink],
 })
-export class AppComponent {}
+export class AppComponent {
+    constructor(@Inject(DOCUMENT) injectedDoc: Document) {
+        injectedDoc.title = 'Example App';
+    }
+}

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

@@ -323,9 +323,10 @@ describe('NgJestCompiler', () => {
             `);
 
             expect(diagnostics.length).toBe(0);
+            // The `type: undefined` is ok here which is covered by example apps' tests.
             expect(code).toContain(dedent`
                 MyDir.ctorParameters = () => [
-                    { type: Document, decorators: [{ type: core_1.Inject, args: [core_1.DOCUMENT,] }] }
+                    { type: undefined, decorators: [{ type: core_1.Inject, args: [core_1.DOCUMENT,] }] }
                 ];
                 exports.MyDir = MyDir = tslib_1.__decorate([
                     (0, core_1.Directive)()

src/compiler/ng-jest-compiler.ts

@@ -7,78 +7,154 @@ import type ts from 'typescript';
 import { angularJitApplicationTransform } from '../transformers/jit_transform';
 import { replaceResources } from '../transformers/replace-resources';
 
-export class NgJestCompiler extends TsCompiler {
-    private readonly _defaultLibDirPath: string;
-    private readonly _libSourceFileCache = new Map<string, ts.SourceFile>();
+const barebonesLibContent = `/// <reference no-default-lib="true"/>
+interface Boolean {}
+interface Function {}
+interface CallableFunction {}
+interface NewableFunction {}
+interface IArguments {}
+interface Number {}
+interface Object {}
+interface RegExp {}
+interface String {}
+interface Array<T> { length: number; [n: number]: T; }
+interface SymbolConstructor {
+    (desc?: string | number): symbol;
+    for(name: string): symbol;
+    readonly toStringTag: symbol;
+}
+declare var Symbol: SymbolConstructor;
+interface Symbol {
+    readonly [Symbol.toStringTag]: string;
+}`;
+const barebonesLibName = 'lib.d.ts';
+let barebonesLibSourceFile: ts.SourceFile | undefined;
 
+export class NgJestCompiler extends TsCompiler {
     constructor(readonly configSet: ConfigSet, readonly jestCacheFS: Map<string, string>) {
         super(configSet, jestCacheFS);
 
         this._logger.debug('created NgJestCompiler');
-        this._defaultLibDirPath = path.dirname(this._ts.getDefaultLibFilePath(this._compilerOptions));
     }
 
     /**
      * Copy from https://github.com/microsoft/TypeScript/blob/master/src/services/transpile.ts
      * This is required because the exposed function `transpileModule` from TypeScript doesn't allow to access `Program`
-     * and we need `Program` to be able to use Angular AST transformers.
+     * and we need `Program` to be able to use Angular `replace-resources` transformer.
      */
     protected _transpileOutput(fileContent: string, filePath: string): ts.TranspileOutput {
-        const scriptTarget = this._compilerOptions.target ?? this._ts.ScriptTarget.Latest;
-        const sourceFile = this._ts.createSourceFile(filePath, fileContent, scriptTarget);
+        barebonesLibSourceFile ??= this._ts.createSourceFile(barebonesLibName, barebonesLibContent, {
+            languageVersion: this._ts.ScriptTarget.Latest,
+        });
+        const diagnostics: ts.Diagnostic[] = [];
+        const compilerOptions = { ...this._compilerOptions };
+        const options: ts.CompilerOptions = compilerOptions
+            ? // @ts-expect-error internal TypeScript API
+              this._ts.fixupCompilerOptions(compilerOptions, diagnostics)
+            : {};
+
+        // mix in default options
+        const defaultOptions = this._ts.getDefaultCompilerOptions();
+        for (const key in defaultOptions) {
+            if (Object.prototype.hasOwnProperty.call(defaultOptions, key) && options[key] === undefined) {
+                options[key] = defaultOptions[key];
+            }
+        }
+
+        // @ts-expect-error internal TypeScript API
+        for (const option of this._ts.transpileOptionValueCompilerOptions) {
+            options[option.name] = option.transpileOptionValue;
+        }
+
+        /**
+         * transpileModule does not write anything to disk so there is no need to verify that there are no conflicts between
+         * input and output paths.
+         */
+        options.suppressOutputPathCheck = true;
+
+        // Filename can be non-ts file.
+        options.allowNonTsExtensions = true;
+
+        // if jsx is specified then treat file as .tsx
+        const inputFileName = filePath || (compilerOptions && compilerOptions.jsx ? 'module.tsx' : 'module.ts');
+        const sourceFile = this._ts.createSourceFile(
+            inputFileName,
+            fileContent,
+            options.target ?? this._ts.ScriptTarget.Latest,
+        );
+
+        let outputText: string | undefined;
+        let sourceMapText: string | undefined;
+
         const compilerHost: ts.CompilerHost = {
             getSourceFile: (fileName) => {
-                if (fileName === path.normalize(filePath)) {
-                    return sourceFile;
-                }
-
-                let libSourceFile = this._libSourceFileCache.get(fileName);
-                if (!libSourceFile) {
-                    const libFilePath = path.join(this._defaultLibDirPath, fileName);
-                    const libFileContent = this._ts.sys.readFile(libFilePath) ?? '';
-                    if (libFileContent) {
-                        libSourceFile = this._ts.createSourceFile(fileName, libFileContent, scriptTarget);
-                        this._libSourceFileCache.set(fileName, libSourceFile);
-                    }
+                return fileName === path.normalize(inputFileName)
+                    ? sourceFile
+                    : fileName === path.normalize(barebonesLibName)
+                    ? barebonesLibSourceFile
+                    : undefined;
+            },
+            writeFile: (name, text) => {
+                if (path.extname(name) === '.map') {
+                    sourceMapText = text;
+                } else {
+                    outputText = text;
                 }
-
-                return libSourceFile;
             },
-            // eslint-disable-next-line @typescript-eslint/no-empty-function
-            writeFile: () => {},
             getDefaultLibFileName: () => 'lib.d.ts',
             useCaseSensitiveFileNames: () => false,
             getCanonicalFileName: (fileName) => fileName,
             getCurrentDirectory: () => '',
             getNewLine: () => os.EOL,
-            fileExists: (fileName) => fileName === filePath,
+            fileExists: (fileName) => fileName === inputFileName,
             readFile: () => '',
             directoryExists: () => true,
             getDirectories: () => [],
         };
-        this.program = this._ts.createProgram([filePath], this._compilerOptions, compilerHost);
 
-        return this._ts.transpileModule(fileContent, {
-            fileName: filePath,
-            transformers: this._makeTransformers(this.configSet.resolvedTransformers),
-            compilerOptions: this._compilerOptions,
-            reportDiagnostics: this.configSet.shouldReportDiagnostics(filePath),
-        });
+        this.program = this._ts.createProgram([inputFileName], options, compilerHost);
+        if (this.configSet.shouldReportDiagnostics(inputFileName)) {
+            diagnostics.push(
+                ...this.program.getSyntacticDiagnostics(sourceFile),
+                ...this.program.getOptionsDiagnostics(),
+            );
+        }
+        this.program.emit(
+            undefined,
+            undefined,
+            undefined,
+            undefined,
+            this._makeTransformers(this.configSet.resolvedTransformers),
+        );
+        if (outputText === undefined) {
+            diagnostics.push({
+                file: sourceFile,
+                start: 0,
+                length: 0,
+                messageText: 'Output generation failed',
+                category: this._ts.DiagnosticCategory.Error,
+                code: 9999,
+                source: fileContent,
+            });
+        }
+
+        return { outputText: outputText ?? '', diagnostics, sourceMapText };
     }
 
     protected _makeTransformers(customTransformers: TsJestAstTransformer): ts.CustomTransformers {
-        const allTransformers = super._makeTransformers(customTransformers);
+        // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
+        const program = this.program!;
 
         return {
-            ...allTransformers.after,
-            ...allTransformers.afterDeclarations,
+            ...super._makeTransformers(customTransformers).after,
+            ...super._makeTransformers(customTransformers).afterDeclarations,
             before: [
-                ...(allTransformers.before ?? []),
-                // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
-                replaceResources(this.program!),
-                // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
-                angularJitApplicationTransform(this.program!),
-            ],
+                ...customTransformers.before.map((beforeTransformer) =>
+                    beforeTransformer.factory(this, beforeTransformer.options),
+                ),
+                replaceResources(program),
+                angularJitApplicationTransform(program),
+            ] as Array<ts.TransformerFactory<ts.SourceFile> | ts.CustomTransformerFactory>,
         };
     }
 }