perf(compiler-cli): detect semantic changes and their effect on an in…

…cremental rebuild

In Angular programs, changing a file may require other files to be
emitted as well due to implicit NgModule dependencies. For example, if
the selector of a directive is changed then all components that have
that directive in their compilation scope need to be recompiled, as the
change of selector may affect the directive matching results.

Until now, the compiler solved this problem using a single dependency
graph. The implicit NgModule dependencies were represented in this
graph, such that a changed file would correctly also cause other files
to be re-emitted. This approach is limited in a few ways:

1. The file dependency graph is used to determine whether it is safe to
   reuse the analysis data of an Angular decorated class. This analysis
   data is invariant to unrelated changes to the NgModule scope, but
   because the single dependency graph also tracked the implicit
   NgModule dependencies the compiler had to consider analysis data as
   stale far more often than necessary.
2. It is typical for a change to e.g. a directive to not affect its
   public API—its selector, inputs, outputs, or exportAs clause—in which
   case there is no need to re-emit all declarations in scope, as their
   compilation output wouldn't have changed.

This commit implements a mechanism by which the compiler is able to
determine the impact of a change by comparing it to the prior
compilation. To achieve this, a new graph is maintained that tracks all
public API information of all Angular decorated symbols. During an
incremental compilation this information is compared to the information
that was captured in the most recently succeeded compilation. This
determines the exact impact of the changes to the public API, which
is then used to determine which files need to be re-emitted.

Note that the file dependency graph remains, as it is still used to
track the dependencies of analysis data. This graph does no longer track
the implicit NgModule dependencies, which allows for better reuse of
analysis data.

This commit also fixes an incorrectness where a change to a declaration
in NgModule `A` would not cause the declarations in NgModules that
import from NgModule `A` to be re-emitted. This was intentionally
incorrect as otherwise the performance of incremental rebuilds would
have been far worse. This is no longer a concern, as the compiler is now
able to only re-emit when actually necessary.

Fixes #34867
Fixes #40635
Closes #40728

packages/compiler-cli/ngcc/BUILD.bazel

@@ -19,6 +19,7 @@ ts_library(
         "//packages/compiler-cli/src/ngtsc/file_system",
         "//packages/compiler-cli/src/ngtsc/imports",
         "//packages/compiler-cli/src/ngtsc/incremental:api",
+        "//packages/compiler-cli/src/ngtsc/incremental/semantic_graph",
         "//packages/compiler-cli/src/ngtsc/logging",
         "//packages/compiler-cli/src/ngtsc/metadata",
         "//packages/compiler-cli/src/ngtsc/partial_evaluator",

packages/compiler-cli/ngcc/src/analysis/decoration_analyzer.ts

@@ -14,6 +14,7 @@ import {CycleAnalyzer, CycleHandlingStrategy, ImportGraph} from '../../../src/ng
 import {isFatalDiagnosticError} from '../../../src/ngtsc/diagnostics';
 import {absoluteFromSourceFile, LogicalFileSystem, ReadonlyFileSystem} from '../../../src/ngtsc/file_system';
 import {AbsoluteModuleStrategy, LocalIdentifierStrategy, LogicalProjectStrategy, ModuleResolver, NOOP_DEFAULT_IMPORT_RECORDER, PrivateExportAliasingHost, Reexport, ReferenceEmitter} from '../../../src/ngtsc/imports';
+import {SemanticSymbol} from '../../../src/ngtsc/incremental/semantic_graph';
 import {CompoundMetadataReader, CompoundMetadataRegistry, DtsMetadataReader, InjectableClassRegistry, LocalMetadataRegistry, ResourceRegistry} from '../../../src/ngtsc/metadata';
 import {PartialEvaluator} from '../../../src/ngtsc/partial_evaluator';
 import {LocalModuleScopeRegistry, MetadataDtsModuleScopeResolver, TypeCheckScopeRegistry} from '../../../src/ngtsc/scope';
@@ -92,7 +93,7 @@ export class DecorationAnalyzer {
   cycleAnalyzer = new CycleAnalyzer(this.importGraph);
   injectableRegistry = new InjectableClassRegistry(this.reflectionHost);
   typeCheckScopeRegistry = new TypeCheckScopeRegistry(this.scopeRegistry, this.fullMetaReader);
-  handlers: DecoratorHandler<unknown, unknown, unknown>[] = [
+  handlers: DecoratorHandler<unknown, unknown, SemanticSymbol|null, unknown>[] = [
     new ComponentDecoratorHandler(
         this.reflectionHost, this.evaluator, this.fullRegistry, this.fullMetaReader,
         this.scopeRegistry, this.scopeRegistry, this.typeCheckScopeRegistry, new ResourceRegistry(),
@@ -103,7 +104,8 @@ export class DecorationAnalyzer {
         /* i18nNormalizeLineEndingsInICUs */ false, this.moduleResolver, this.cycleAnalyzer,
         CycleHandlingStrategy.UseRemoteScoping, this.refEmitter, NOOP_DEFAULT_IMPORT_RECORDER,
         NOOP_DEPENDENCY_TRACKER, this.injectableRegistry,
-        !!this.compilerOptions.annotateForClosureCompiler),
+        /* semanticDepGraphUpdater */ null, !!this.compilerOptions.annotateForClosureCompiler),
+
     // See the note in ngtsc about why this cast is needed.
     // clang-format off
     new DirectiveDecoratorHandler(
@@ -115,7 +117,7 @@ export class DecorationAnalyzer {
         // in ngtsc, but we want to ensure compatibility in ngcc for outdated libraries that
         // have not migrated to explicit decorators. See: https://hackmd.io/@alx/ryfYYuvzH.
         /* compileUndecoratedClassesWithAngularFeatures */ true
-    ) as DecoratorHandler<unknown, unknown, unknown>,
+    ) as DecoratorHandler<unknown, unknown, SemanticSymbol|null,unknown>,
     // clang-format on
     // Pipe handler must be before injectable handler in list so pipe factories are printed
     // before injectable factories (so injectable factories can delegate to them)

packages/compiler-cli/ngcc/src/analysis/ngcc_trait_compiler.ts

@@ -8,6 +8,7 @@
 import * as ts from 'typescript';
 
 import {IncrementalBuild} from '../../../src/ngtsc/incremental/api';
+import {SemanticSymbol} from '../../../src/ngtsc/incremental/semantic_graph';
 import {NOOP_PERF_RECORDER} from '../../../src/ngtsc/perf';
 import {ClassDeclaration, Decorator} from '../../../src/ngtsc/reflection';
 import {CompilationMode, DecoratorHandler, DtsTransformRegistry, HandlerFlags, Trait, TraitCompiler} from '../../../src/ngtsc/transform';
@@ -22,11 +23,12 @@ import {isDefined} from '../utils';
  */
 export class NgccTraitCompiler extends TraitCompiler {
   constructor(
-      handlers: DecoratorHandler<unknown, unknown, unknown>[],
+      handlers: DecoratorHandler<unknown, unknown, SemanticSymbol|null, unknown>[],
       private ngccReflector: NgccReflectionHost) {
     super(
         handlers, ngccReflector, NOOP_PERF_RECORDER, new NoIncrementalBuild(),
-        /* compileNonExportedClasses */ true, CompilationMode.FULL, new DtsTransformRegistry());
+        /* compileNonExportedClasses */ true, CompilationMode.FULL, new DtsTransformRegistry(),
+        /* semanticDepGraphUpdater */ null);
   }
 
   get analyzedFiles(): ts.SourceFile[] {
@@ -54,7 +56,7 @@ export class NgccTraitCompiler extends TraitCompiler {
    * @param flags optional bitwise flag to influence the compilation of the decorator.
    */
   injectSyntheticDecorator(clazz: ClassDeclaration, decorator: Decorator, flags?: HandlerFlags):
-      Trait<unknown, unknown, unknown>[] {
+      Trait<unknown, unknown, SemanticSymbol|null, unknown>[] {
     const migratedTraits = this.detectTraits(clazz, [decorator]);
     if (migratedTraits === null) {
       return [];

packages/compiler-cli/ngcc/src/analysis/util.ts

@@ -16,8 +16,6 @@ export function isWithinPackage(packagePath: AbsoluteFsPath, filePath: AbsoluteF
 class NoopDependencyTracker implements DependencyTracker {
   addDependency(): void {}
   addResourceDependency(): void {}
-  addTransitiveDependency(): void {}
-  addTransitiveResources(): void {}
   recordDependencyAnalysisFailure(): void {}
 }
 

packages/compiler-cli/ngcc/test/BUILD.bazel

@@ -19,6 +19,7 @@ ts_library(
         "//packages/compiler-cli/src/ngtsc/file_system",
         "//packages/compiler-cli/src/ngtsc/file_system/testing",
         "//packages/compiler-cli/src/ngtsc/imports",
+        "//packages/compiler-cli/src/ngtsc/incremental/semantic_graph",
         "//packages/compiler-cli/src/ngtsc/logging/testing",
         "//packages/compiler-cli/src/ngtsc/partial_evaluator",
         "//packages/compiler-cli/src/ngtsc/reflection",

packages/compiler-cli/ngcc/test/analysis/decoration_analyzer_spec.ts

@@ -10,6 +10,7 @@ import * as ts from 'typescript';
 import {FatalDiagnosticError, makeDiagnostic} from '../../../src/ngtsc/diagnostics';
 import {absoluteFrom, getFileSystem, getSourceFileOrError} from '../../../src/ngtsc/file_system';
 import {runInEachFileSystem, TestFile} from '../../../src/ngtsc/file_system/testing';
+import {SemanticSymbol} from '../../../src/ngtsc/incremental/semantic_graph';
 import {MockLogger} from '../../../src/ngtsc/logging/testing';
 import {ClassDeclaration, DeclarationNode, Decorator} from '../../../src/ngtsc/reflection';
 import {loadFakeCore, loadTestFiles} from '../../../src/ngtsc/testing';
@@ -21,8 +22,9 @@ import {Esm2015ReflectionHost} from '../../src/host/esm2015_host';
 import {Migration, MigrationHost} from '../../src/migrations/migration';
 import {getRootFiles, makeTestEntryPointBundle} from '../helpers/utils';
 
-type DecoratorHandlerWithResolve = DecoratorHandler<unknown, unknown, unknown>&{
-  resolve: NonNullable<DecoratorHandler<unknown, unknown, unknown>['resolve']>;
+type DecoratorHandlerWithResolve =
+    DecoratorHandler<unknown, unknown, SemanticSymbol|null, unknown>&{
+  resolve: NonNullable<DecoratorHandler<unknown, unknown, SemanticSymbol|null, unknown>['resolve']>;
 };
 
 runInEachFileSystem(() => {
@@ -46,6 +48,7 @@ runInEachFileSystem(() => {
         const handler = jasmine.createSpyObj<DecoratorHandlerWithResolve>('TestDecoratorHandler', [
           'detect',
           'analyze',
+          'symbol',
           'register',
           'resolve',
           'compileFull',
@@ -442,7 +445,7 @@ runInEachFileSystem(() => {
 
       describe('declaration files', () => {
         it('should not run decorator handlers against declaration files', () => {
-          class FakeDecoratorHandler implements DecoratorHandler<{}|null, unknown, unknown> {
+          class FakeDecoratorHandler implements DecoratorHandler<{}|null, unknown, null, unknown> {
             name = 'FakeDecoratorHandler';
             precedence = HandlerPrecedence.PRIMARY;
 
@@ -452,6 +455,9 @@ runInEachFileSystem(() => {
             analyze(): AnalysisOutput<unknown> {
               throw new Error('analyze should not have been called');
             }
+            symbol(): null {
+              throw new Error('symbol should not have been called');
+            }
             compileFull(): CompileResult {
               throw new Error('compile should not have been called');
             }

packages/compiler-cli/ngcc/test/analysis/migration_host_spec.ts

@@ -11,6 +11,7 @@ import * as ts from 'typescript';
 import {makeDiagnostic} from '../../../src/ngtsc/diagnostics';
 import {absoluteFrom} from '../../../src/ngtsc/file_system';
 import {runInEachFileSystem} from '../../../src/ngtsc/file_system/testing';
+import {SemanticSymbol} from '../../../src/ngtsc/incremental/semantic_graph';
 import {MockLogger} from '../../../src/ngtsc/logging/testing';
 import {ClassDeclaration, Decorator, isNamedClassDeclaration} from '../../../src/ngtsc/reflection';
 import {getDeclaration, loadTestFiles} from '../../../src/ngtsc/testing';
@@ -44,7 +45,8 @@ runInEachFileSystem(() => {
     });
 
     function createMigrationHost({entryPoint, handlers}: {
-      entryPoint: EntryPointBundle; handlers: DecoratorHandler<unknown, unknown, unknown>[]
+      entryPoint: EntryPointBundle;
+      handlers: DecoratorHandler<unknown, unknown, SemanticSymbol|null, unknown>[]
     }) {
       const reflectionHost = new Esm2015ReflectionHost(new MockLogger(), false, entryPoint.src);
       const compiler = new NgccTraitCompiler(handlers, reflectionHost);
@@ -190,7 +192,7 @@ runInEachFileSystem(() => {
   });
 });
 
-class DetectDecoratorHandler implements DecoratorHandler<unknown, unknown, unknown> {
+class DetectDecoratorHandler implements DecoratorHandler<unknown, unknown, null, unknown> {
   readonly name = DetectDecoratorHandler.name;
 
   constructor(private decorator: string, readonly precedence: HandlerPrecedence) {}
@@ -210,12 +212,16 @@ class DetectDecoratorHandler implements DecoratorHandler<unknown, unknown, unkno
     return {};
   }
 
+  symbol(node: ClassDeclaration, analysis: Readonly<unknown>): null {
+    return null;
+  }
+
   compileFull(node: ClassDeclaration): CompileResult|CompileResult[] {
     return [];
   }
 }
 
-class DiagnosticProducingHandler implements DecoratorHandler<unknown, unknown, unknown> {
+class DiagnosticProducingHandler implements DecoratorHandler<unknown, unknown, null, unknown> {
   readonly name = DiagnosticProducingHandler.name;
   readonly precedence = HandlerPrecedence.PRIMARY;
 
@@ -228,6 +234,10 @@ class DiagnosticProducingHandler implements DecoratorHandler<unknown, unknown, u
     return {diagnostics: [makeDiagnostic(9999, node, 'test diagnostic')]};
   }
 
+  symbol(node: ClassDeclaration, analysis: Readonly<unknown>): null {
+    return null;
+  }
+
   compileFull(node: ClassDeclaration): CompileResult|CompileResult[] {
     return [];
   }

packages/compiler-cli/ngcc/test/analysis/ngcc_trait_compiler_spec.ts

@@ -9,6 +9,7 @@
 import {ErrorCode, makeDiagnostic, ngErrorCode} from '../../../src/ngtsc/diagnostics';
 import {absoluteFrom} from '../../../src/ngtsc/file_system';
 import {runInEachFileSystem} from '../../../src/ngtsc/file_system/testing';
+import {SemanticSymbol} from '../../../src/ngtsc/incremental/semantic_graph';
 import {MockLogger} from '../../../src/ngtsc/logging/testing';
 import {ClassDeclaration, Decorator, isNamedClassDeclaration} from '../../../src/ngtsc/reflection';
 import {getDeclaration, loadTestFiles} from '../../../src/ngtsc/testing';
@@ -39,7 +40,8 @@ runInEachFileSystem(() => {
     });
 
     function createCompiler({entryPoint, handlers}: {
-      entryPoint: EntryPointBundle; handlers: DecoratorHandler<unknown, unknown, unknown>[]
+      entryPoint: EntryPointBundle;
+      handlers: DecoratorHandler<unknown, unknown, SemanticSymbol|null, unknown>[]
     }) {
       const reflectionHost = new Esm2015ReflectionHost(new MockLogger(), false, entryPoint.src);
       return new NgccTraitCompiler(handlers, reflectionHost);
@@ -295,7 +297,7 @@ runInEachFileSystem(() => {
   });
 });
 
-class TestHandler implements DecoratorHandler<unknown, unknown, unknown> {
+class TestHandler implements DecoratorHandler<unknown, unknown, null, unknown> {
   constructor(readonly name: string, protected log: string[]) {}
 
   precedence = HandlerPrecedence.PRIMARY;
@@ -310,6 +312,10 @@ class TestHandler implements DecoratorHandler<unknown, unknown, unknown> {
     return {};
   }
 
+  symbol(node: ClassDeclaration, analysis: Readonly<unknown>): null {
+    return null;
+  }
+
   compileFull(node: ClassDeclaration): CompileResult|CompileResult[] {
     this.log.push(this.name + ':compile:' + node.name.text);
     return [];

packages/compiler-cli/ngcc/test/host/util.ts

@@ -7,6 +7,8 @@
  */
 import {Trait, TraitState} from '@angular/compiler-cli/src/ngtsc/transform';
 import * as ts from 'typescript';
+
+import {SemanticSymbol} from '../../../src/ngtsc/incremental/semantic_graph';
 import {CtorParameter, TypeValueReferenceKind} from '../../../src/ngtsc/reflection';
 
 /**
@@ -50,7 +52,8 @@ export function expectTypeValueReferencesForParameters(
   });
 }
 
-export function getTraitDiagnostics(trait: Trait<unknown, unknown, unknown>): ts.Diagnostic[]|null {
+export function getTraitDiagnostics(trait: Trait<unknown, unknown, SemanticSymbol|null, unknown>):
+    ts.Diagnostic[]|null {
   if (trait.state === TraitState.Analyzed) {
     return trait.analysisDiagnostics;
   } else if (trait.state === TraitState.Resolved) {

packages/compiler-cli/src/ngtsc/annotations/BUILD.bazel

@@ -14,6 +14,7 @@ ts_library(
         "//packages/compiler-cli/src/ngtsc/file_system",
         "//packages/compiler-cli/src/ngtsc/imports",
         "//packages/compiler-cli/src/ngtsc/incremental:api",
+        "//packages/compiler-cli/src/ngtsc/incremental/semantic_graph",
         "//packages/compiler-cli/src/ngtsc/indexer",
         "//packages/compiler-cli/src/ngtsc/metadata",
         "//packages/compiler-cli/src/ngtsc/partial_evaluator",