refactor(ngcc): abstract work orchestration/execution behind an interface (#32427)

This change does not alter the current behavior, but makes it easier to
introduce new types of `Executors` , for example to do the required work
in parallel (on multiple processes).

Inspired by/Based on @alxhub's prototype: alxhub/angular@cb631bdb1

PR Close #32427

packages/compiler-cli/ngcc/src/execution/api.ts

@@ -20,12 +20,21 @@ export type CompileFn = (task: Task) => void;
 /** The type of the function that creates the `CompileFn` function used to process tasks. */
 export type CreateCompileFn = (onTaskCompleted: TaskCompletedCallback) => CompileFn;
 
+/** Options related to the orchestration/execution of tasks. */
+export interface ExecutionOptions {
+  compileAllFormats: boolean;
+  propertiesToConsider: string[];
+}
+
 /**
- * The type of the function that orchestrates and executes the required work (i.e. analyzes the
- * entry-points, processes the resulting tasks, does book-keeping and validates the final outcome).
+ * A class that orchestrates and executes the required work (i.e. analyzes the entry-points,
+ * processes the resulting tasks, does book-keeping and validates the final outcome).
  */
-export type ExecuteFn =
-    (analyzeEntryPoints: AnalyzeEntryPointsFn, createCompileFn: CreateCompileFn) => void;
+export interface Executor {
+  execute(
+      analyzeEntryPoints: AnalyzeEntryPointsFn, createCompileFn: CreateCompileFn,
+      options: ExecutionOptions): void;
+}
 
 /** Represents metadata related to the processing of an entry-point. */
 export interface EntryPointProcessingMetadata {

packages/compiler-cli/ngcc/src/execution/single_process_executor.ts

@@ -0,0 +1,46 @@
+/**
+ * @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 {Logger} from '../logging/logger';
+import {PackageJsonUpdater} from '../writing/package_json_updater';
+
+import {AnalyzeEntryPointsFn, CreateCompileFn, ExecutionOptions, Executor} from './api';
+import {checkForUnprocessedEntryPoints, onTaskCompleted} from './utils';
+
+
+/**
+ * An `Executor` that processes all tasks serially and completes synchronously.
+ */
+export class SingleProcessExecutor implements Executor {
+  constructor(private logger: Logger, private pkgJsonUpdater: PackageJsonUpdater) {}
+
+  execute(
+      analyzeEntryPoints: AnalyzeEntryPointsFn, createCompileFn: CreateCompileFn,
+      options: ExecutionOptions): void {
+    this.logger.debug(`Running ngcc on ${this.constructor.name}.`);
+
+    const {processingMetadataPerEntryPoint, tasks} = analyzeEntryPoints();
+    const compile = createCompileFn(
+        (task, outcome) =>
+            onTaskCompleted(this.pkgJsonUpdater, processingMetadataPerEntryPoint, task, outcome));
+
+    // Process all tasks.
+    for (const task of tasks) {
+      const processingMeta = processingMetadataPerEntryPoint.get(task.entryPoint.path) !;
+
+      // If we only need one format processed and we already have one for the corresponding
+      // entry-point, skip the task.
+      if (!options.compileAllFormats && processingMeta.hasAnyProcessedFormat) continue;
+
+      compile(task);
+    }
+
+    // Check for entry-points for which we could not process any format at all.
+    checkForUnprocessedEntryPoints(processingMetadataPerEntryPoint, options.propertiesToConsider);
+  }
+}

packages/compiler-cli/ngcc/src/execution/utils.ts

@@ -0,0 +1,59 @@
+/**
+ * @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 {resolve} from '../../../src/ngtsc/file_system';
+import {markAsProcessed} from '../packages/build_marker';
+import {PackageJsonFormatProperties} from '../packages/entry_point';
+import {PackageJsonUpdater} from '../writing/package_json_updater';
+
+import {EntryPointProcessingMetadata, Task, TaskProcessingOutcome} from './api';
+
+
+/**
+ * A helper function for checking for unprocessed entry-points (i.e. entry-points for which we could
+ * not process any format at all).
+ */
+export const checkForUnprocessedEntryPoints =
+    (processingMetadataPerEntryPoint: Map<string, EntryPointProcessingMetadata>,
+     propertiesToConsider: string[]): void => {
+      const unprocessedEntryPointPaths =
+          Array.from(processingMetadataPerEntryPoint.entries())
+              .filter(([, processingMeta]) => !processingMeta.hasAnyProcessedFormat)
+              .map(([entryPointPath]) => `\n  - ${entryPointPath}`)
+              .join('');
+
+      if (unprocessedEntryPointPaths) {
+        throw new Error(
+            'Failed to compile any formats for the following entry-points (tried ' +
+            `${propertiesToConsider.join(', ')}): ${unprocessedEntryPointPaths}`);
+      }
+    };
+
+/** A helper function for handling a task's being completed. */
+export const onTaskCompleted =
+    (pkgJsonUpdater: PackageJsonUpdater,
+     processingMetadataPerEntryPoint: Map<string, EntryPointProcessingMetadata>, task: Task,
+     outcome: TaskProcessingOutcome, ): void => {
+      const {entryPoint, formatPropertiesToMarkAsProcessed, processDts} = task;
+      const processingMeta = processingMetadataPerEntryPoint.get(entryPoint.path) !;
+      processingMeta.hasAnyProcessedFormat = true;
+
+      if (outcome === TaskProcessingOutcome.Processed) {
+        const packageJsonPath = resolve(entryPoint.path, 'package.json');
+        const propsToMarkAsProcessed: PackageJsonFormatProperties[] =
+            [...formatPropertiesToMarkAsProcessed];
+
+        if (processDts) {
+          processingMeta.hasProcessedTypings = true;
+          propsToMarkAsProcessed.push('typings');
+        }
+
+        markAsProcessed(
+            pkgJsonUpdater, entryPoint.packageJson, packageJsonPath, propsToMarkAsProcessed);
+      }
+    };