refactor(compiler-cli): optimize extra import generation in local com…

…pilation mode

packages/compiler-cli/src/ngtsc/annotations/component/src/handler.ts

@@ -774,6 +774,12 @@ export class ComponentDecoratorHandler implements
  // Dependencies from the `@Component.deferredImports` field.
  const explicitlyDeferredDependencies = getExplicitlyDeferredDeps(scope);
 
+ // Mark the component is an NgModule-based component with its NgModule in a different file
+ // then mark this file for extra import generation
+ if (isModuleScope && context.fileName !== getSourceFile(scope.ngModule).fileName) {
+ this.localCompilationExtraImportsTracker?.markFileForExtraImportGeneration(context);
+ }
+
  // Make sure that `@Component.imports` and `@Component.deferredImports` do not have
  // the same dependencies.
  if (metadata.isStandalone && analysis.rawDeferredImports !== null &&

packages/compiler-cli/src/ngtsc/imports/src/local_compilation_extra_imports_tracker.ts

@@ -37,8 +37,23 @@ export class LocalCompilationExtraImportsTracker {
  private readonly localImportsMap = new Map<string, Set<string>>();
  private readonly globalImportsSet = new Set<string>();
 
+ /** Names of the files marked for extra import generation. */
+ private readonly markedFilesSet = new Set<string>();
+
  constructor(private readonly typeChecker: ts.TypeChecker) {}
 
+ /**
+ * Marks the source file for extra imports generation.
+ *
+ * The extra imports are generated only for the files marked through this method. In other words,
+ * the method {@link getImportsForFile} returns empty if the file is not marked. This allows the
+ * consumers of this tool to avoid generating extra imports for unrelated files (e.g., non-Angular
+ * files)
+ */
+ markFileForExtraImportGeneration(sf: ts.SourceFile) {
+ this.markedFilesSet.add(sf.fileName);
+ }
+
  /**
  * Adds an extra import to be added to the generated file of a specific source file.
  */
@@ -91,6 +106,10 @@ export class LocalCompilationExtraImportsTracker {
  * Returns the list of all module names that the given file should include as its extra imports.
  */
  getImportsForFile(sf: ts.SourceFile): string[] {
+ if (!this.markedFilesSet.has(sf.fileName)) {
+ return [];
+ }
+
  return [
  ...this.globalImportsSet,
  ...(this.localImportsMap.get(sf.fileName) ?? []),