refactor(@angular-devkit/build-angular): allow internal Angular compilation control of diagnostic modes

To support generate diagnostics in varying ways, the internal compilation classes
now support a `modes` argument when diagnosing files during a build using the `application` builder.
This is not exposed as an option at this time but can be experimented with a build using the
`NG_BUILD_TYPE_CHECK` environment variable. This environment variable is not considered part of the
public API and may be removed or altered in the future. Its current purpose is to allow profiling
of the type checking diagnostics functionality of the build system.

Author: clydin

packages/angular_devkit/build_angular/src/tools/esbuild/angular/compilation/angular-compilation.ts

@@ -20,6 +20,14 @@ export interface EmitFileResult {
   dependencies?: readonly string[];
 }
 
+export enum DiagnosticModes {
+  None = 0,
+  Option = 1 << 0,
+  Syntactic = 1 << 1,
+  Semantic = 1 << 2,
+  All = Option | Syntactic | Semantic,
+}
+
 export abstract class AngularCompilation {
   static #angularCompilerCliModule?: typeof ng;
   static #typescriptModule?: typeof ts;
@@ -71,19 +79,21 @@ export abstract class AngularCompilation {
 
   abstract emitAffectedFiles(): Iterable<EmitFileResult> | Promise<Iterable<EmitFileResult>>;
 
-  protected abstract collectDiagnostics():
-    | Iterable<ts.Diagnostic>
-    | Promise<Iterable<ts.Diagnostic>>;
+  protected abstract collectDiagnostics(
+    modes: DiagnosticModes,
+  ): Iterable<ts.Diagnostic> | Promise<Iterable<ts.Diagnostic>>;
 
-  async diagnoseFiles(): Promise<{ errors?: PartialMessage[]; warnings?: PartialMessage[] }> {
+  async diagnoseFiles(
+    modes = DiagnosticModes.All,
+  ): Promise<{ errors?: PartialMessage[]; warnings?: PartialMessage[] }> {
     const result: { errors?: PartialMessage[]; warnings?: PartialMessage[] } = {};
 
     // Avoid loading typescript until actually needed.
     // This allows for avoiding the load of typescript in the main thread when using the parallel compilation.
     const typescript = await AngularCompilation.loadTypescript();
 
     await profileAsync('NG_DIAGNOSTICS_TOTAL', async () => {
-      for (const diagnostic of await this.collectDiagnostics()) {
+      for (const diagnostic of await this.collectDiagnostics(modes)) {
         const message = convertTypeScriptDiagnostic(typescript, diagnostic);
         if (diagnostic.category === typescript.DiagnosticCategory.Error) {
           (result.errors ??= []).push(message);

packages/angular_devkit/build_angular/src/tools/esbuild/angular/compilation/aot-compilation.ts

@@ -16,7 +16,7 @@ import {
   ensureSourceFileVersions,
 } from '../angular-host';
 import { createWorkerTransformer } from '../web-worker-transformer';
-import { AngularCompilation, EmitFileResult } from './angular-compilation';
+import { AngularCompilation, DiagnosticModes, EmitFileResult } from './angular-compilation';
 
 // Temporary deep import for transformer support
 // TODO: Move these to a private exports location or move the implementation into this package.
@@ -127,7 +127,7 @@ export class AotCompilation extends AngularCompilation {
     return { affectedFiles, compilerOptions, referencedFiles };
   }
 
-  *collectDiagnostics(): Iterable<ts.Diagnostic> {
+  *collectDiagnostics(modes: DiagnosticModes): Iterable<ts.Diagnostic> {
     assert(this.#state, 'Angular compilation must be initialized prior to collecting diagnostics.');
     const {
       affectedFiles,
@@ -137,25 +137,39 @@ export class AotCompilation extends AngularCompilation {
       typeScriptProgram,
     } = this.#state;
 
+    const syntactic = modes & DiagnosticModes.Syntactic;
+    const semantic = modes & DiagnosticModes.Semantic;
+
     // Collect program level diagnostics
-    yield* typeScriptProgram.getConfigFileParsingDiagnostics();
-    yield* angularCompiler.getOptionDiagnostics();
-    yield* typeScriptProgram.getOptionsDiagnostics();
-    yield* typeScriptProgram.getGlobalDiagnostics();
+    if (modes & DiagnosticModes.Option) {
+      yield* typeScriptProgram.getConfigFileParsingDiagnostics();
+      yield* angularCompiler.getOptionDiagnostics();
+      yield* typeScriptProgram.getOptionsDiagnostics();
+    }
+    if (syntactic) {
+      yield* typeScriptProgram.getGlobalDiagnostics();
+    }
 
     // Collect source file specific diagnostics
     for (const sourceFile of typeScriptProgram.getSourceFiles()) {
       if (angularCompiler.ignoreForDiagnostics.has(sourceFile)) {
         continue;
       }
 
-      // TypeScript will use cached diagnostics for files that have not been
-      // changed or affected for this build when using incremental building.
-      yield* profileSync(
-        'NG_DIAGNOSTICS_SYNTACTIC',
-        () => typeScriptProgram.getSyntacticDiagnostics(sourceFile),
-        true,
-      );
+      if (syntactic) {
+        // TypeScript will use cached diagnostics for files that have not been
+        // changed or affected for this build when using incremental building.
+        yield* profileSync(
+          'NG_DIAGNOSTICS_SYNTACTIC',
+          () => typeScriptProgram.getSyntacticDiagnostics(sourceFile),
+          true,
+        );
+      }
+
+      if (!semantic) {
+        continue;
+      }
+
       yield* profileSync(
         'NG_DIAGNOSTICS_SEMANTIC',
         () => typeScriptProgram.getSemanticDiagnostics(sourceFile),

packages/angular_devkit/build_angular/src/tools/esbuild/angular/compilation/index.ts

@@ -6,6 +6,6 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-export { AngularCompilation } from './angular-compilation';
+export { AngularCompilation, DiagnosticModes } from './angular-compilation';
 export { createAngularCompilation } from './factory';
 export { NoopCompilation } from './noop-compilation';

packages/angular_devkit/build_angular/src/tools/esbuild/angular/compilation/jit-compilation.ts

@@ -13,7 +13,7 @@ import { profileSync } from '../../profiling';
 import { AngularHostOptions, createAngularCompilerHost } from '../angular-host';
 import { createJitResourceTransformer } from '../jit-resource-transformer';
 import { createWorkerTransformer } from '../web-worker-transformer';
-import { AngularCompilation, EmitFileResult } from './angular-compilation';
+import { AngularCompilation, DiagnosticModes, EmitFileResult } from './angular-compilation';
 
 class JitCompilationState {
   constructor(
@@ -82,18 +82,26 @@ export class JitCompilation extends AngularCompilation {
     return { affectedFiles, compilerOptions, referencedFiles };
   }
 
-  *collectDiagnostics(): Iterable<ts.Diagnostic> {
+  *collectDiagnostics(modes: DiagnosticModes): Iterable<ts.Diagnostic> {
     assert(this.#state, 'Compilation must be initialized prior to collecting diagnostics.');
     const { typeScriptProgram } = this.#state;
 
     // Collect program level diagnostics
-    yield* typeScriptProgram.getConfigFileParsingDiagnostics();
-    yield* typeScriptProgram.getOptionsDiagnostics();
-    yield* typeScriptProgram.getGlobalDiagnostics();
-    yield* profileSync('NG_DIAGNOSTICS_SYNTACTIC', () =>
-      typeScriptProgram.getSyntacticDiagnostics(),
-    );
-    yield* profileSync('NG_DIAGNOSTICS_SEMANTIC', () => typeScriptProgram.getSemanticDiagnostics());
+    if (modes & DiagnosticModes.Option) {
+      yield* typeScriptProgram.getConfigFileParsingDiagnostics();
+      yield* typeScriptProgram.getOptionsDiagnostics();
+    }
+    if (modes & DiagnosticModes.Syntactic) {
+      yield* typeScriptProgram.getGlobalDiagnostics();
+      yield* profileSync('NG_DIAGNOSTICS_SYNTACTIC', () =>
+        typeScriptProgram.getSyntacticDiagnostics(),
+      );
+    }
+    if (modes & DiagnosticModes.Semantic) {
+      yield* profileSync('NG_DIAGNOSTICS_SEMANTIC', () =>
+        typeScriptProgram.getSemanticDiagnostics(),
+      );
+    }
   }
 
   emitAffectedFiles(): Iterable<EmitFileResult> {

packages/angular_devkit/build_angular/src/tools/esbuild/angular/compilation/parallel-compilation.ts

@@ -13,7 +13,7 @@ import { MessageChannel } from 'node:worker_threads';
 import Piscina from 'piscina';
 import type { SourceFile } from 'typescript';
 import type { AngularHostOptions } from '../angular-host';
-import { AngularCompilation, EmitFileResult } from './angular-compilation';
+import { AngularCompilation, DiagnosticModes, EmitFileResult } from './angular-compilation';
 
 /**
  * An Angular compilation which uses a Node.js Worker thread to load and execute
@@ -122,8 +122,10 @@ export class ParallelCompilation extends AngularCompilation {
     throw new Error('Not implemented in ParallelCompilation.');
   }
 
-  override diagnoseFiles(): Promise<{ errors?: PartialMessage[]; warnings?: PartialMessage[] }> {
-    return this.#worker.run(undefined, { name: 'diagnose' });
+  override diagnoseFiles(
+    modes = DiagnosticModes.All,
+  ): Promise<{ errors?: PartialMessage[]; warnings?: PartialMessage[] }> {
+    return this.#worker.run(modes, { name: 'diagnose' });
   }
 
   override emitAffectedFiles(): Promise<Iterable<EmitFileResult>> {

packages/angular_devkit/build_angular/src/tools/esbuild/angular/compilation/parallel-worker.ts

@@ -11,7 +11,7 @@ import assert from 'node:assert';
 import { randomUUID } from 'node:crypto';
 import { type MessagePort, receiveMessageOnPort } from 'node:worker_threads';
 import { SourceFileCache } from '../source-file-cache';
-import type { AngularCompilation } from './angular-compilation';
+import type { AngularCompilation, DiagnosticModes } from './angular-compilation';
 import { AotCompilation } from './aot-compilation';
 import { JitCompilation } from './jit-compilation';
 
@@ -99,13 +99,13 @@ export async function initialize(request: InitRequest) {
   };
 }
 
-export async function diagnose(): Promise<{
+export async function diagnose(modes: DiagnosticModes): Promise<{
   errors?: PartialMessage[];
   warnings?: PartialMessage[];
 }> {
   assert(compilation);
 
-  const diagnostics = await compilation.diagnoseFiles();
+  const diagnostics = await compilation.diagnoseFiles(modes);
 
   return diagnostics;
 }

packages/angular_devkit/build_angular/src/tools/esbuild/angular/compiler-plugin.ts

@@ -17,13 +17,18 @@ import type {
 } from 'esbuild';
 import assert from 'node:assert';
 import * as path from 'node:path';
-import { maxWorkers } from '../../../utils/environment-options';
+import { maxWorkers, useTypeChecking } from '../../../utils/environment-options';
 import { JavaScriptTransformer } from '../javascript-transformer';
 import { LoadResultCache, createCachedLoad } from '../load-result-cache';
 import { logCumulativeDurations, profileAsync, resetCumulativeDurations } from '../profiling';
 import { BundleStylesheetOptions } from '../stylesheets/bundle-options';
 import { AngularHostOptions } from './angular-host';
-import { AngularCompilation, NoopCompilation, createAngularCompilation } from './compilation';
+import {
+  AngularCompilation,
+  DiagnosticModes,
+  NoopCompilation,
+  createAngularCompilation,
+} from './compilation';
 import { SharedTSCompilationState, getSharedCompilationState } from './compilation-state';
 import { ComponentStylesheetBundler } from './component-stylesheets';
 import { FileReferenceTracker } from './file-reference-tracker';
@@ -258,14 +263,6 @@ export function createCompilerPlugin(
           return result;
         }
 
-        const diagnostics = await compilation.diagnoseFiles();
-        if (diagnostics.errors?.length) {
-          (result.errors ??= []).push(...diagnostics.errors);
-        }
-        if (diagnostics.warnings?.length) {
-          (result.warnings ??= []).push(...diagnostics.warnings);
-        }
-
         // Update TypeScript file output cache for all affected files
         try {
           await profileAsync('NG_EMIT_TS', async () => {
@@ -286,6 +283,16 @@ export function createCompilerPlugin(
           });
         }
 
+        const diagnostics = await compilation.diagnoseFiles(
+          useTypeChecking ? DiagnosticModes.All : DiagnosticModes.All & ~DiagnosticModes.Semantic,
+        );
+        if (diagnostics.errors?.length) {
+          (result.errors ??= []).push(...diagnostics.errors);
+        }
+        if (diagnostics.warnings?.length) {
+          (result.warnings ??= []).push(...diagnostics.warnings);
+        }
+
         // Add errors from failed additional results.
         // This must be done after emit to capture latest web worker results.
         for (const { errors } of additionalResults.values()) {

packages/angular_devkit/build_angular/src/utils/environment-options.ts

@@ -102,3 +102,7 @@ export const debugPerformance = isPresent(debugPerfVariable) && isEnabled(debugP
 
 const watchRootVariable = process.env['NG_BUILD_WATCH_ROOT'];
 export const shouldWatchRoot = isPresent(watchRootVariable) && isEnabled(watchRootVariable);
+
+const typeCheckingVariable = process.env['NG_BUILD_TYPE_CHECK'];
+export const useTypeChecking =
+  !isPresent(typeCheckingVariable) || !isDisabled(typeCheckingVariable);