[CFE] Run widget transformer before constant evaluation.

Change-Id: I51ded35ecb95cb5cfbac5ecf8967e0918a48269a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/101987
Commit-Queue: Aske Simon Christensen <askesc@google.com>
Reviewed-by: Jacob Richman <jacobr@google.com>

pkg/dev_compiler/lib/src/kernel/command.dart

@@ -13,7 +13,6 @@ import 'package:front_end/src/api_unstable/ddc.dart' as fe;
 import 'package:kernel/kernel.dart' hide MapEntry;
 import 'package:kernel/text/ast_to_text.dart' as kernel show Printer;
 import 'package:kernel/binary/ast_to_binary.dart' as kernel show BinaryPrinter;
-import 'package:kernel/transformations/track_widget_constructor_locations.dart';
 import 'package:path/path.dart' as path;
 import 'package:source_maps/source_maps.dart' show SourceMapBuilder;
 
@@ -213,6 +212,9 @@ Future<CompilerResult> _compile(List<String> args,
     }
   }
 
+  bool trackWidgetCreation =
+      argResults['track-widget-creation'] as bool ?? false;
+
   var oldCompilerState = compilerState;
   List<Component> doneInputSummaries;
   fe.IncrementalCompiler incrementalCompiler;
@@ -224,7 +226,7 @@ Future<CompilerResult> _compile(List<String> args,
         sourcePathToUri(packageFile),
         sourcePathToUri(librarySpecPath),
         summaryModules.keys.toList(),
-        DevCompilerTarget(),
+        DevCompilerTarget(trackWidgetCreation: trackWidgetCreation),
         fileSystem: fileSystem,
         experiments: experiments);
   } else {
@@ -236,7 +238,7 @@ Future<CompilerResult> _compile(List<String> args,
         sourcePathToUri(packageFile),
         sourcePathToUri(librarySpecPath),
         summaryModules.keys.toList(),
-        DevCompilerTarget(),
+        DevCompilerTarget(trackWidgetCreation: trackWidgetCreation),
         fileSystem: fileSystem,
         experiments: experiments);
     incrementalCompiler = compilerState.incrementalCompiler;
@@ -320,13 +322,6 @@ Future<CompilerResult> _compile(List<String> args,
     hierarchy = target.hierarchy;
   }
 
-  // TODO(jmesserly): remove this hack once Flutter SDK has a `dartdevc` with
-  // support for the widget inspector.
-  if (argResults['track-widget-creation'] as bool) {
-    component.computeCanonicalNames();
-    WidgetCreatorTracker().transform(component);
-  }
-
   var compiler =
       ProgramCompiler(component, hierarchy, options, declaredVariables);
 

pkg/dev_compiler/lib/src/kernel/target.dart

@@ -8,11 +8,16 @@ import 'package:kernel/kernel.dart';
 import 'package:kernel/core_types.dart';
 import 'package:kernel/class_hierarchy.dart';
 import 'package:kernel/target/targets.dart';
+import 'package:kernel/transformations/track_widget_constructor_locations.dart';
 import 'constants.dart' show DevCompilerConstantsBackend;
 import 'kernel_helpers.dart';
 
 /// A kernel [Target] to configure the Dart Front End for dartdevc.
 class DevCompilerTarget extends Target {
+  DevCompilerTarget({this.trackWidgetCreation = false});
+
+  final bool trackWidgetCreation;
+
   ClassHierarchy hierarchy;
 
   bool get legacyMode => false;
@@ -87,6 +92,18 @@ class DevCompilerTarget extends Target {
     }
   }
 
+  @override
+  void performPreConstantEvaluationTransformations(
+      Component component,
+      CoreTypes coreTypes,
+      List<Library> libraries,
+      DiagnosticReporter diagnosticReporter,
+      {void logger(String msg)}) {
+    if (trackWidgetCreation) {
+      WidgetCreatorTracker().transform(component, libraries);
+    }
+  }
+
   @override
   Expression instantiateInvocation(CoreTypes coreTypes, Expression receiver,
       String name, Arguments arguments, int offset, bool isSuper) {

pkg/front_end/lib/src/fasta/kernel/kernel_target.dart

@@ -774,6 +774,12 @@ class KernelTarget extends TargetImplementation {
   /// Run all transformations that are needed when building a bundle of
   /// libraries for the first time.
   void runBuildTransformations() {
+    backendTarget.performPreConstantEvaluationTransformations(
+        component,
+        loader.coreTypes,
+        loader.libraries,
+        new KernelDiagnosticReporter(loader),
+        logger: (String msg) => ticker.logMs(msg));
     if (loader.target.enableConstantUpdate2018) {
       TypeEnvironment environment =
           new TypeEnvironment(loader.coreTypes, loader.hierarchy);

pkg/kernel/lib/target/targets.dart

@@ -115,6 +115,15 @@ abstract class Target {
   /// slowing down compilation.
   void performOutlineTransformations(Component component) {}
 
+  /// Perform target-specific transformations on the given libraries that must
+  /// run before constant evaluation.
+  void performPreConstantEvaluationTransformations(
+      Component component,
+      CoreTypes coreTypes,
+      List<Library> libraries,
+      DiagnosticReporter diagnosticReporter,
+      {void logger(String msg)}) {}
+
   /// Perform target-specific modular transformations on the given libraries.
   void performModularTransformationsOnLibraries(
       Component component,

pkg/kernel/lib/transformations/track_widget_constructor_locations.dart

@@ -414,15 +414,13 @@ class WidgetCreatorTracker {
     clazz.constructors.forEach(handleConstructor);
   }
 
-  /// Transform the given [module].
-  void transform(Component module) {
-    final List<Library> libraries = module.libraries;
-
+  /// Transform the given [libraries].
+  void transform(Component module, List<Library> libraries) {
     if (libraries.isEmpty) {
       return;
     }
 
-    _resolveFlutterClasses(libraries);
+    _resolveFlutterClasses(module.libraries);
 
     if (_widgetClass == null) {
       // This application doesn't actually use the package:flutter library.
@@ -431,9 +429,9 @@ class WidgetCreatorTracker {
 
     final Set<Class> transformedClasses = new Set<Class>.identity();
     final Set<Library> librariesToTransform = new Set<Library>.identity()
-      ..addAll(module.libraries);
+      ..addAll(libraries);
 
-    for (Library library in module.libraries) {
+    for (Library library in libraries) {
       if (library.isExternal) {
         continue;
       }
@@ -453,7 +451,7 @@ class WidgetCreatorTracker {
             locationClass: _locationClass,
             tracker: this);
 
-    for (Library library in module.libraries) {
+    for (Library library in libraries) {
       if (library.isExternal) {
         continue;
       }

pkg/vm/lib/target/flutter.dart

@@ -3,11 +3,17 @@
 // BSD-style license that can be found in the LICENSE file.
 library vm.target.flutter;
 
+import 'package:kernel/ast.dart' show Component, Library;
+import 'package:kernel/core_types.dart' show CoreTypes;
 import 'package:kernel/target/targets.dart';
+import 'package:kernel/transformations/track_widget_constructor_locations.dart';
 import 'package:vm/target/vm.dart' show VmTarget;
 
 class FlutterTarget extends VmTarget {
-  FlutterTarget(TargetFlags flags) : super(flags);
+  FlutterTarget(TargetFlags flags, {this.trackWidgetCreation = false})
+      : super(flags);
+
+  final bool trackWidgetCreation;
 
   @override
   String get name => 'flutter';
@@ -41,4 +47,16 @@ class FlutterTarget extends VmTarget {
         'dart:ui',
         'dart:vmservice_io',
       ];
+
+  @override
+  void performPreConstantEvaluationTransformations(
+      Component component,
+      CoreTypes coreTypes,
+      List<Library> libraries,
+      DiagnosticReporter diagnosticReporter,
+      {void logger(String msg)}) {
+    if (trackWidgetCreation) {
+      new WidgetCreatorTracker().transform(component, libraries);
+    }
+  }
 }

utils/bazel/kernel_worker.dart

@@ -19,7 +19,6 @@ import 'package:dev_compiler/src/kernel/target.dart';
 import 'package:front_end/src/api_unstable/bazel_worker.dart' as fe;
 import 'package:kernel/ast.dart' show Component, Library;
 import 'package:kernel/target/targets.dart';
-import 'package:kernel/transformations/track_widget_constructor_locations.dart';
 import 'package:vm/target/vm.dart';
 import 'package:vm/target/flutter.dart';
 import 'package:vm/target/flutter_runner.dart';
@@ -175,11 +174,6 @@ Future<ComputeKernelResult> computeKernel(List<String> args,
   var summaryOnly = parsedArgs['summary-only'] as bool;
   var trackKernelCreation = parsedArgs['track-kernel-creation'] as bool;
 
-  if (summaryOnly && trackKernelCreation) {
-    throw new ArgumentError('error: --summary-only is not compatible with '
-        '--track-kernel-creation');
-  }
-
   // TODO(sigmund,jakemac): make target mandatory. We allow null to be backwards
   // compatible while we migrate existing clients of this tool.
   var targetName =
@@ -194,7 +188,8 @@ Future<ComputeKernelResult> computeKernel(List<String> args,
       }
       break;
     case 'flutter':
-      target = new FlutterTarget(targetFlags);
+      target = new FlutterTarget(targetFlags,
+          trackWidgetCreation: trackKernelCreation);
       if (summaryOnly) {
         throw new ArgumentError(
             'error: --summary-only not supported for the flutter target');
@@ -217,7 +212,8 @@ Future<ComputeKernelResult> computeKernel(List<String> args,
     case 'ddc':
       // TODO(jakemac):If `generateKernel` changes to return a summary
       // component, process the component instead.
-      target = new DevCompilerSummaryTarget(sources, excludeNonSources);
+      target = new DevCompilerSummaryTarget(sources, excludeNonSources,
+          trackWidgetCreation: trackKernelCreation);
       if (!summaryOnly) {
         out.writeln('error: --no-summary-only not supported for the '
             'ddc target');
@@ -296,8 +292,6 @@ Future<ComputeKernelResult> computeKernel(List<String> args,
         incrementalComponent.problemsAsJson = null;
         incrementalComponent.mainMethod = null;
         target.performOutlineTransformations(incrementalComponent);
-      } else if (trackKernelCreation) {
-        (new WidgetCreatorTracker()).transform(incrementalComponent);
       }
 
       return Future.value(fe.serializeComponent(incrementalComponent));
@@ -307,10 +301,6 @@ Future<ComputeKernelResult> computeKernel(List<String> args,
   } else {
     Component component =
         await fe.compileComponent(state, sources, onDiagnostic);
-
-    if (trackKernelCreation) {
-      (new WidgetCreatorTracker()).transform(component);
-    }
     kernel = fe.serializeComponent(component,
         filter: (library) => sources.contains(library.importUri));
   }
@@ -342,7 +332,9 @@ class DevCompilerSummaryTarget extends DevCompilerTarget {
   final List<Uri> sources;
   final bool excludeNonSources;
 
-  DevCompilerSummaryTarget(this.sources, this.excludeNonSources);
+  DevCompilerSummaryTarget(this.sources, this.excludeNonSources,
+      {trackWidgetCreation = false})
+      : super(trackWidgetCreation: trackWidgetCreation);
 
   @override
   void performOutlineTransformations(Component component) {