fix(@angular/build): aggregate parallel worker performance timings on the main thread

Rather than having the parallel worker thread print its cumulative durations separately to the console (which causes console spam and disjointed/incomplete final logs), we serialize and return the worker's durations to the main thread upon completing the diagnostics task. The main thread then merges them into the global cumulative durations map, producing a single, complete, and perfectly aggregated performance report at the end of the build.

(cherry picked from commit 851711b)

Author: alan-agius4

packages/angular/build/src/tools/angular/compilation/parallel-compilation.ts

@@ -12,6 +12,7 @@ import { createRequire } from 'node:module';
 import { MessageChannel } from 'node:worker_threads';
 import type { SourceFile } from 'typescript';
 import { WorkerPool } from '../../../utils/worker-pool';
+import { mergeCumulativeDurations } from '../../esbuild/profiling';
 import type { AngularHostOptions } from '../angular-host';
 import { AngularCompilation, DiagnosticModes, EmitFileResult } from './angular-compilation';
 
@@ -124,10 +125,15 @@ export class ParallelCompilation extends AngularCompilation {
     throw new Error('Not implemented in ParallelCompilation.');
   }
 
-  override diagnoseFiles(
+  override async diagnoseFiles(
     modes = DiagnosticModes.All,
   ): Promise<{ errors?: PartialMessage[]; warnings?: PartialMessage[] }> {
-    return this.#worker.run(modes, { name: 'diagnose' });
+    const { timings, ...result } = await this.#worker.run(modes, { name: 'diagnose' });
+    if (timings) {
+      mergeCumulativeDurations(timings);
+    }
+
+    return result;
   }
 
   override emitAffectedFiles(): Promise<Iterable<EmitFileResult>> {

packages/angular/build/src/tools/angular/compilation/parallel-worker.ts

@@ -11,6 +11,7 @@ import assert from 'node:assert';
 import { randomUUID } from 'node:crypto';
 import { type MessagePort, receiveMessageOnPort } from 'node:worker_threads';
 import { SourceFileCache } from '../../esbuild/angular/source-file-cache';
+import { getAndClearCumulativeDurations } from '../../esbuild/profiling';
 import type { AngularCompilation, DiagnosticModes } from './angular-compilation';
 import { AotCompilation } from './aot-compilation';
 import { JitCompilation } from './jit-compilation';
@@ -121,12 +122,17 @@ export async function initialize(request: InitRequest) {
 export async function diagnose(modes: DiagnosticModes): Promise<{
   errors?: PartialMessage[];
   warnings?: PartialMessage[];
+  timings?: Record<string, number[]>;
 }> {
   assert(compilation);
 
   const diagnostics = await compilation.diagnoseFiles(modes);
+  const timings = getAndClearCumulativeDurations();
 
-  return diagnostics;
+  return {
+    ...diagnostics,
+    timings,
+  };
 }
 
 export async function emit() {

packages/angular/build/src/tools/esbuild/profiling.ts

@@ -14,6 +14,32 @@ export function resetCumulativeDurations(): void {
   cumulativeDurations?.clear();
 }
 
+export function getAndClearCumulativeDurations(): Record<string, number[]> | undefined {
+  if (!cumulativeDurations || cumulativeDurations.size === 0) {
+    return undefined;
+  }
+
+  const data = Object.fromEntries(cumulativeDurations);
+
+  cumulativeDurations.clear();
+
+  return data;
+}
+
+export function mergeCumulativeDurations(data: Record<string, number[]>): void {
+  cumulativeDurations ??= new Map();
+
+  for (const [name, durations] of Object.entries(data)) {
+    let existing = cumulativeDurations.get(name);
+    if (!existing) {
+      existing = [];
+      cumulativeDurations.set(name, existing);
+    }
+
+    existing.push(...durations);
+  }
+}
+
 export function logCumulativeDurations(): void {
   if (!debugPerformance || !cumulativeDurations) {
     return;