perf(@ngtools/webpack): Improve rebuild performance

Keep the TypeScript SourceFile around so we don't regenerate all of them
when we rebuild the Program. The rebuild time is now 40-50% faster for
hello world. This means all the files which haven't changed are not
reparsed.

Mentions: angular#1980, angular#4020, angular#3315

Author: hansl

packages/@ngtools/webpack/src/compiler_host.ts

@@ -68,6 +68,10 @@ export class VirtualFileStats extends VirtualStats {
   set content(v: string) {
     this._content = v;
     this._mtime = new Date();
+    this._sourceFile = null;
+  }
+  setSourceFile(sourceFile: ts.SourceFile) {
+    this._sourceFile = sourceFile;
   }
   getSourceFile(languageVersion: ts.ScriptTarget, setParentNodes: boolean) {
     if (!this._sourceFile) {
@@ -156,16 +160,25 @@ export class WebpackCompilerHost implements ts.CompilerHost {
     this._changed = false;
   }
 
+  invalidate(fileName: string): void {
+    delete this._files[fileName];
+  }
+
   fileExists(fileName: string): boolean {
     fileName = this._resolve(fileName);
     return fileName in this._files || this._delegate.fileExists(fileName);
   }
 
   readFile(fileName: string): string {
     fileName = this._resolve(fileName);
-    return (fileName in this._files)
-         ? this._files[fileName].content
-         : this._delegate.readFile(fileName);
+    if (!(fileName in this._files)) {
+      const result = this._delegate.readFile(fileName);
+      if (result) {
+        this._setFileContent(fileName, result);
+        return result;
+      }
+    }
+    return this._files[fileName].content;
   }
 
   directoryExists(directoryName: string): boolean {
@@ -199,7 +212,7 @@ export class WebpackCompilerHost implements ts.CompilerHost {
     fileName = this._resolve(fileName);
 
     if (!(fileName in this._files)) {
-      return this._delegate.getSourceFile(fileName, languageVersion, onError);
+      this.readFile(fileName);
     }
 
     return this._files[fileName].getSourceFile(languageVersion, this._setParentNodes);

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

@@ -194,6 +194,10 @@ export class AotPlugin implements Tapable {
   apply(compiler: any) {
     this._compiler = compiler;
 
+    compiler.plugin('invalid', (fileName: string, timestamp: number) => {
+      this._compilerHost.invalidate(fileName);
+    });
+
     compiler.plugin('context-module-factory', (cmf: any) => {
       cmf.plugin('before-resolve', (request: any, callback: (err?: any, request?: any) => void) => {
         if (!request) {
@@ -253,6 +257,7 @@ export class AotPlugin implements Tapable {
     if (this._compilation._ngToolsWebpackPluginInstance) {
       return cb(new Error('An @ngtools/webpack plugin already exist for this compilation.'));
     }
+
     this._compilation._ngToolsWebpackPluginInstance = this;
 
     this._resourceLoader = new WebpackResourceLoader(compilation);
@@ -286,18 +291,20 @@ export class AotPlugin implements Tapable {
           this._rootFilePath, this._compilerOptions, this._compilerHost, this._program);
       })
       .then(() => {
-        const diagnostics = this._program.getGlobalDiagnostics();
-        if (diagnostics.length > 0) {
-          const message = diagnostics
-            .map(diagnostic => {
-              const {line, character} = diagnostic.file.getLineAndCharacterOfPosition(
-                diagnostic.start);
-              const message = ts.flattenDiagnosticMessageText(diagnostic.messageText, '\n');
-              return `${diagnostic.file.fileName} (${line + 1},${character + 1}): ${message})`;
-            })
-            .join('\n');
-
-          throw new Error(message);
+        if (this._typeCheck) {
+          const diagnostics = this._program.getGlobalDiagnostics();
+          if (diagnostics.length > 0) {
+            const message = diagnostics
+              .map(diagnostic => {
+                const {line, character} = diagnostic.file.getLineAndCharacterOfPosition(
+                  diagnostic.start);
+                const message = ts.flattenDiagnosticMessageText(diagnostic.messageText, '\n');
+                return `${diagnostic.file.fileName} (${line + 1},${character + 1}): ${message})`;
+              })
+              .join('\n');
+
+            throw new Error(message);
+          }
         }
       })
       .then(() => {

packages/@ngtools/webpack/src/refactor.ts

@@ -60,12 +60,15 @@ export class TypeScriptFileRefactor {
     if (!this._program) {
       return [];
     }
-    let diagnostics: ts.Diagnostic[] = this._program.getSyntacticDiagnostics(this._sourceFile)
-                              .concat(this._program.getSemanticDiagnostics(this._sourceFile));
+    let diagnostics: ts.Diagnostic[] = [];
     // only concat the declaration diagnostics if the tsconfig config sets it to true.
     if (this._program.getCompilerOptions().declaration == true) {
       diagnostics = diagnostics.concat(this._program.getDeclarationDiagnostics(this._sourceFile));
     }
+    diagnostics = diagnostics.concat(
+      this._program.getSyntacticDiagnostics(this._sourceFile),
+      this._program.getSemanticDiagnostics(this._sourceFile));
+
     return diagnostics;
   }
 

packages/angular-cli/models/webpack-build-common.ts

@@ -37,6 +37,7 @@ export function getWebpackCommonConfig(
 
   const appRoot = path.resolve(projectRoot, appConfig.root);
   const nodeModules = path.resolve(projectRoot, 'node_modules');
+  const angularCoreNodeModules = path.resolve(projectRoot, 'node_modules/@angular/core');
 
   let extraPlugins: any[] = [];
   let extraRules: any[] = [];
@@ -68,11 +69,22 @@ export function getWebpackCommonConfig(
   }
 
   if (vendorChunk) {
-    extraPlugins.push(new webpack.optimize.CommonsChunkPlugin({
-      name: 'vendor',
-      chunks: ['main'],
-      minChunks: (module: any) => module.userRequest && module.userRequest.startsWith(nodeModules)
-    }));
+    extraPlugins.push(
+      new webpack.optimize.CommonsChunkPlugin({
+        name: 'vendor',
+        chunks: ['main'],
+        minChunks: (module: any) => {
+          return module.userRequest && module.userRequest.startsWith(nodeModules)
+              && !module.userRequest.startsWith(angularCoreNodeModules);
+        }
+      }),
+      new webpack.optimize.CommonsChunkPlugin({
+        name: 'angular',
+        chunks: ['main'],
+        minChunks: (module: any) => {
+          return module.userRequest && module.userRequest.startsWith(angularCoreNodeModules);
+        }
+      }));
   }
 
   // process environment file replacement