feat(@ngtools/webpack): support Webpack 5

The `@ngtools/webpack` package now officially supports Webpack 5.
It is also now built against Webpack 5 types.  Webpack 4 support is temporarily maintained while the remainder of the tooling is transitioned.

packages/ngtools/webpack/package.json

@@ -28,12 +28,12 @@
   "peerDependencies": {
     "@angular/compiler-cli": "^12.0.0-next",
     "typescript": "~4.0.0 || ~4.1.0",
-    "webpack": "^4.0.0"
+    "webpack": "^4.0.0 || ^5.20.0"
   },
   "devDependencies": {
     "@angular/compiler": "12.0.0-next.0",
     "@angular/compiler-cli": "12.0.0-next.0",
     "typescript": "4.1.5",
-    "webpack": "4.44.2"
+    "webpack": "5.21.2"
   }
 }

packages/ngtools/webpack/src/angular_compiler_plugin.ts

@@ -34,7 +34,7 @@ import { ChildProcess, ForkOptions, fork } from 'child_process';
 import * as fs from 'fs';
 import * as path from 'path';
 import * as ts from 'typescript';
-import { Compiler, compilation } from 'webpack';
+import { Compiler, WebpackFourCompiler, compilation } from 'webpack';
 import { time, timeEnd } from './benchmark';
 import { WebpackCompilerHost } from './compiler_host';
 import { DiagnosticMode, gatherDiagnostics, hasErrors, reportDiagnostics } from './diagnostics';
@@ -75,10 +75,6 @@ import {
   VirtualFileSystemDecorator,
   VirtualWatchFileSystemDecorator,
 } from './virtual_file_system_decorator';
-import {
-  NodeWatchFileSystemInterface,
-  NormalModuleFactoryRequest,
-} from './webpack';
 import { addError, addWarning } from './webpack-diagnostics';
 import { createWebpackInputHost } from './webpack-input-host';
 import { isWebpackFiveOrHigher, mergeResolverMainFields } from './webpack-version';
@@ -686,7 +682,10 @@ export class AngularCompilerPlugin {
     };
 
     // Go over all the modules in the webpack compilation and remove them from the sets.
-    compilation.modules.forEach(m => m.resource ? removeSourceFile(m.resource, true) : null);
+    // tslint:disable-next-line: no-any
+    compilation.modules.forEach((m: compilation.Module & { resource?: string }) =>
+      m.resource ? removeSourceFile(m.resource, true) : null,
+    );
 
     // Anything that remains is unused, because it wasn't referenced directly or transitively
     // on the files in the compilation.
@@ -712,7 +711,12 @@ export class AngularCompilerPlugin {
 
   // Registration hook for webpack plugin.
   // tslint:disable-next-line:no-big-function
-  apply(compiler: Compiler & { watchMode?: boolean, parentCompilation?: compilation.Compilation }) {
+  apply(webpackCompiler: Compiler | WebpackFourCompiler) {
+    const compiler = webpackCompiler as Compiler & {
+      watchMode?: boolean;
+      parentCompilation?: compilation.Compilation;
+      watchFileSystem?: unknown;
+    };
     // The below is require by NGCC processor
     // since we need to know which fields we need to process
     compiler.hooks.environment.tap('angular-compiler', () => {
@@ -748,13 +752,8 @@ export class AngularCompilerPlugin {
     // Decorate inputFileSystem to serve contents of CompilerHost.
     // Use decorated inputFileSystem in watchFileSystem.
     compiler.hooks.environment.tap('angular-compiler', () => {
-      // The webpack types currently do not include these
-      const compilerWithFileSystems = compiler as Compiler & {
-        watchFileSystem: NodeWatchFileSystemInterface,
-      };
-
       let host: virtualFs.Host<fs.Stats> = this._options.host || createWebpackInputHost(
-        compilerWithFileSystems.inputFileSystem,
+        compiler.inputFileSystem,
       );
 
       let replacements: Map<Path, Path> | ((path: Path) => Path) | undefined;
@@ -791,7 +790,7 @@ export class AngularCompilerPlugin {
           this._errors,
           this._basePath,
           this._tsConfigPath,
-          compilerWithFileSystems.inputFileSystem,
+          compiler.inputFileSystem,
           compiler.options.resolve?.symlinks,
         );
 
@@ -830,11 +829,11 @@ export class AngularCompilerPlugin {
       }
 
       const inputDecorator = new VirtualFileSystemDecorator(
-        compilerWithFileSystems.inputFileSystem,
+        compiler.inputFileSystem,
         this._compilerHost,
       );
-      compilerWithFileSystems.inputFileSystem = inputDecorator;
-      compilerWithFileSystems.watchFileSystem = new VirtualWatchFileSystemDecorator(
+      compiler.inputFileSystem = inputDecorator;
+      compiler.watchFileSystem = new VirtualWatchFileSystemDecorator(
         inputDecorator,
         replacements,
       );
@@ -956,7 +955,7 @@ export class AngularCompilerPlugin {
         // when the issuer is a `.ts` or `.ngfactory.js` file.
         nmf.hooks.beforeResolve.tapPromise(
           'angular-compiler',
-          async (request?: NormalModuleFactoryRequest) => {
+          async (request) => {
             if (this.done && request) {
               const name = request.request;
               const issuer = request.contextInfo.issuer;

packages/ngtools/webpack/src/ivy/cache.ts

@@ -10,14 +10,23 @@ import { normalizePath } from './paths';
 
 export class SourceFileCache extends Map<string, ts.SourceFile> {
   invalidate(
-    fileTimestamps: Map<string, number | { timestamp: number } | null>,
+    fileTimestamps: Map<string, 'ignore' | number | { safeTime: number } | null>,
     buildTimestamp: number,
   ): Set<string> {
     const changedFiles = new Set<string>();
     for (const [file, timeOrEntry] of fileTimestamps) {
-      const time =
-        timeOrEntry && (typeof timeOrEntry === 'number' ? timeOrEntry : timeOrEntry.timestamp);
-      if (time === null || buildTimestamp < time) {
+      if (timeOrEntry === 'ignore') {
+        continue;
+      }
+
+      let time;
+      if (typeof timeOrEntry === 'number') {
+        time = timeOrEntry;
+      } else if (timeOrEntry) {
+        time = timeOrEntry.safeTime;
+      }
+
+      if (!time || time >= buildTimestamp) {
         // Cache stores paths using the POSIX directory separator
         const normalizedFile = normalizePath(file);
         this.delete(normalizedFile);

packages/ngtools/webpack/src/ivy/plugin.ts

@@ -14,6 +14,7 @@ import {
   Compiler,
   ContextReplacementPlugin,
   NormalModuleReplacementPlugin,
+  WebpackFourCompiler,
   compilation,
 } from 'webpack';
 import { NgccProcessor } from '../ngcc_processor';
@@ -33,7 +34,7 @@ import {
 } from './host';
 import { externalizePath, normalizePath } from './paths';
 import { AngularPluginSymbol, EmitFileResult, FileEmitter } from './symbol';
-import { createWebpackSystem } from './system';
+import { InputFileSystemSync, createWebpackSystem } from './system';
 import { createAotTransformers, createJitTransformers, mergeTransformers } from './transformation';
 
 export interface AngularPluginOptions {
@@ -50,7 +51,8 @@ export interface AngularPluginOptions {
 
 // Add support for missing properties in Webpack types as well as the loader's file emitter
 interface WebpackCompilation extends compilation.Compilation {
-  compilationDependencies: Set<string>;
+  // tslint:disable-next-line: no-any
+  compilationDependencies: { add(item: string): any };
   rebuildModule(module: compilation.Module, callback: () => void): void;
   [AngularPluginSymbol]: FileEmitter;
 }
@@ -113,7 +115,8 @@ export class AngularWebpackPlugin {
     return this.pluginOptions;
   }
 
-  apply(compiler: Compiler & { watchMode?: boolean }): void {
+  apply(webpackCompiler: Compiler | WebpackFourCompiler): void {
+    const compiler = webpackCompiler as Compiler & { watchMode?: boolean };
     // Setup file replacements with webpack
     for (const [key, value] of Object.entries(this.pluginOptions.fileReplacements)) {
       new NormalModuleReplacementPlugin(
@@ -188,7 +191,11 @@ export class AngularWebpackPlugin {
       pathsPlugin.update(compilerOptions);
 
       // Create a Webpack-based TypeScript compiler host
-      const system = createWebpackSystem(compiler.inputFileSystem, normalizePath(compiler.context));
+      const system = createWebpackSystem(
+        // Webpack lacks an InputFileSytem type definition with sync functions
+        compiler.inputFileSystem as InputFileSystemSync,
+        normalizePath(compiler.context),
+      );
       const host = ts.createIncrementalCompilerHost(compilerOptions, system);
 
       // Setup source file caching and reuse cache from previous compilation if present
@@ -267,7 +274,7 @@ export class AngularWebpackPlugin {
             .filter((sourceFile) => !sourceFile.isDeclarationFile)
             .map((sourceFile) => sourceFile.fileName),
         );
-        modules.forEach(({ resource }: compilation.Module & { resource?: string }) => {
+        Array.from(modules).forEach(({ resource }: compilation.Module & { resource?: string }) => {
           const sourceFile = resource && builder.getSourceFile(resource);
           if (!sourceFile) {
             return;
@@ -303,7 +310,7 @@ export class AngularWebpackPlugin {
     }
 
     const rebuild = (webpackModule: compilation.Module) =>
-      new Promise<void>((resolve) => compilation.rebuildModule(webpackModule, resolve));
+      new Promise<void>((resolve) => compilation.rebuildModule(webpackModule, () => resolve()));
 
     const filesToRebuild = new Set<string>();
     for (const requiredFile of this.requiredFilesToEmit) {

packages/ngtools/webpack/src/ivy/system.ts

@@ -9,11 +9,19 @@ import * as ts from 'typescript';
 import { InputFileSystem } from 'webpack';
 import { externalizePath } from './paths';
 
+export interface InputFileSystemSync extends InputFileSystem {
+  readFileSync(path: string): Buffer;
+  statSync(path: string): { size: number; mtime: Date; isDirectory(): boolean; isFile(): boolean };
+}
+
 function shouldNotWrite(): never {
   throw new Error('Webpack TypeScript System should not write.');
 }
 
-export function createWebpackSystem(input: InputFileSystem, currentDirectory: string): ts.System {
+export function createWebpackSystem(
+  input: InputFileSystemSync,
+  currentDirectory: string,
+): ts.System {
   // Webpack's CachedInputFileSystem uses the default directory separator in the paths it uses
   // for keys to its cache. If the keys do not match then the file watcher will not purge outdated
   // files and cause stale data to be used in the next rebuild. TypeScript always uses a `/` (POSIX)

packages/ngtools/webpack/src/paths-plugin.ts

@@ -7,10 +7,16 @@
  */
 import * as path from 'path';
 import { CompilerOptions, MapLike } from 'typescript';
-import { NormalModuleFactoryRequest } from './webpack';
 
 const getInnerRequest = require('enhanced-resolve/lib/getInnerRequest');
 
+interface NormalModuleFactoryRequest {
+  request: string;
+  context: { issuer: string };
+  contextInfo: { issuer: string };
+  typescriptPathMapped?: boolean;
+}
+
 export interface TypeScriptPathsPluginOptions extends Pick<CompilerOptions, 'paths' | 'baseUrl'> {
 
 }

packages/ngtools/webpack/src/virtual_file_system_decorator.ts

@@ -9,9 +9,17 @@ import { FileDoesNotExistException, Path, getSystemPath, normalize } from '@angu
 import { Stats } from 'fs';
 import { InputFileSystem } from 'webpack';
 import { WebpackCompilerHost } from './compiler_host';
-import { NodeWatchFileSystemInterface } from './webpack';
 import { isWebpackFiveOrHigher } from './webpack-version';
 
+interface NodeWatchFileSystemInterface {
+  inputFileSystem: InputFileSystem;
+  new(inputFileSystem: InputFileSystem): NodeWatchFileSystemInterface;
+  // tslint:disable-next-line:no-any
+  watch(files: any, dirs: any, missing: any, startTime: any, options: any, callback: any,
+        // tslint:disable-next-line:no-any
+        callbackUndelayed: any): any;
+}
+
 export const NodeWatchFileSystem: NodeWatchFileSystemInterface = require(
   'webpack/lib/node/NodeWatchFileSystem');
 
@@ -61,7 +69,12 @@ export class VirtualFileSystemDecorator implements InputFileSystem {
     (this._inputFileSystem as any).readJson(path, callback);
   }
 
-  readlink(path: string, callback: (err: Error | null | undefined, linkString: string) => void): void {
+  readlink(
+    path: string,
+    // Callback types differ between Webpack 4 and 5
+    // tslint:disable-next-line: no-any
+    callback: (err: any, linkString: any) => void,
+  ): void {
     this._inputFileSystem.readlink(path, callback);
   }
 
@@ -89,7 +102,9 @@ export class VirtualFileSystemDecorator implements InputFileSystem {
   }
 
   readlinkSync(path: string): string {
-    return this._inputFileSystem.readlinkSync(path);
+    // Synchronous functions are missing from the Webpack typings
+    // tslint:disable-next-line: no-any
+    return (this._inputFileSystem as any).readlinkSync(path);
   }
 
   purge(changes?: string[] | string): void {

packages/ngtools/webpack/src/webpack-input-host.ts

@@ -25,7 +25,9 @@ export function createWebpackInputHost(inputFileSystem: InputFileSystem) {
     },
 
     read(path): virtualFs.FileBuffer {
-      const data = inputFileSystem.readFileSync(getSystemPath(path));
+      // Synchronous functions are missing from the Webpack typings
+      // tslint:disable-next-line: no-any
+      const data = (inputFileSystem as any).readFileSync(getSystemPath(path));
 
       return new Uint8Array(data).buffer as ArrayBuffer;
     },
@@ -53,7 +55,9 @@ export function createWebpackInputHost(inputFileSystem: InputFileSystem) {
 
     stat(path): Stats | null {
       try {
-        return inputFileSystem.statSync(getSystemPath(path));
+        // Synchronous functions are missing from the Webpack typings
+        // tslint:disable-next-line: no-any
+        return (inputFileSystem as any).statSync(getSystemPath(path));
       } catch (e) {
         if (e.code === 'ENOENT') {
           return null;

packages/ngtools/webpack/src/webpack.d.ts

@@ -0,0 +1,25 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+import * as webpack from 'webpack';
+import { Compiler as webpack4Compiler, loader as webpack4Loader } from '@types/webpack';
+
+// Webpack 5 transition support types
+declare module 'webpack' {
+  export type WebpackFourCompiler = webpack4Compiler;
+
+  export type InputFileSystem = webpack.Compiler['inputFileSystem'];
+
+  export namespace compilation {
+    export type Compilation = webpack.Compilation;
+    export type Module = webpack.Module;
+  }
+
+  export namespace loader {
+    export type LoaderContext = webpack4Loader.LoaderContext;
+  }
+}