[cfe] Handle patch factories through fragments

Change-Id: I11a5b2e113d854ae159a823359ddbdd8e796f6db
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/415281
Commit-Queue: Johnni Winther <[email protected]>
Reviewed-by: Jens Johansen <[email protected]>

Author: johnniwinther

pkg/front_end/lib/src/builder/builder.dart

@@ -277,7 +277,6 @@ abstract class BuilderImpl implements Builder {
   bool get isConst => false;
 
   @override
-  // Coverage-ignore(suite): Not run.
   bool get isConstructor => false;
 
   @override
@@ -324,7 +323,7 @@ abstract class BuilderImpl implements Builder {
   bool get isLocal => false;
 
   @override
-  bool get isAugmenting => this != origin;
+  bool get isAugmenting => false;
 
   @override
   bool get isAugment => false;

pkg/front_end/lib/src/fragment/factory.dart

@@ -30,6 +30,8 @@ class FactoryFragment implements Fragment, FunctionFragment {
 
   SourceFactoryBuilder? _builder;
 
+  FactoryDeclaration? _declaration;
+
   FactoryFragment({
     required this.constructorName,
     required this.fileUri,
@@ -65,6 +67,18 @@ class FactoryFragment implements Fragment, FunctionFragment {
     _builder = value;
   }
 
+  FactoryDeclaration get declaration {
+    assert(
+        _declaration != null, "Declaration has not been computed for $this.");
+    return _declaration!;
+  }
+
+  void set declaration(FactoryDeclaration value) {
+    assert(_declaration == null,
+        "Declaration has already been computed for $this.");
+    _declaration = value;
+  }
+
   @override
   FunctionBodyBuildingContext createFunctionBodyBuildingContext() {
     return new _FactoryBodyBuildingContext(this);
@@ -108,7 +122,7 @@ class _FactoryBodyBuildingContext implements FunctionBodyBuildingContext {
 
   @override
   BodyBuilderContext createBodyBuilderContext() {
-    return _fragment.builder.createBodyBuilderContext();
+    return _fragment.declaration.createBodyBuilderContext(_fragment.builder);
   }
 
   @override
@@ -119,9 +133,8 @@ class _FactoryBodyBuildingContext implements FunctionBodyBuildingContext {
       ?.inferenceData;
 
   @override
-  List<TypeParameter>? get thisTypeParameters =>
-      _fragment.builder.thisTypeParameters;
+  List<TypeParameter>? get thisTypeParameters => null;
 
   @override
-  VariableDeclaration? get thisVariable => _fragment.builder.thisVariable;
+  VariableDeclaration? get thisVariable => null;
 }

pkg/front_end/lib/src/source/constructor_declaration.dart

@@ -6,13 +6,15 @@ import 'package:kernel/ast.dart';
 
 import '../kernel/expression_generator_helper.dart';
 import '../type_inference/inference_results.dart';
-import 'source_function_builder.dart';
+import 'source_member_builder.dart';
 import 'source_property_builder.dart';
 
 /// Common interface for builders for generative constructor declarations in
 /// source code, such as a generative constructor in a regular class or a
 /// generative constructor in an extension type declaration.
-abstract class ConstructorDeclarationBuilder implements SourceFunctionBuilder {
+abstract class ConstructorDeclarationBuilder implements SourceMemberBuilder {
+  FunctionNode get function;
+
   /// Returns `true` if this constructor, including its augmentations, is
   /// external.
   ///

pkg/front_end/lib/src/source/source_class_builder.dart

@@ -908,8 +908,7 @@ class SourceClassBuilder extends ClassBuilderImpl
           // Report an error if a mixin class has a constructor with parameters,
           // is external, or is a redirecting constructor.
           if (constructor.isRedirecting ||
-              (constructor.formals != null &&
-                  constructor.formals!.isNotEmpty) ||
+              constructor.hasParameters ||
               constructor.isExternal) {
             addProblem(
                 templateIllegalMixinDueToConstructors

pkg/front_end/lib/src/source/source_constructor_builder.dart

@@ -39,7 +39,6 @@ import '../type_inference/type_inference_engine.dart';
 import 'constructor_declaration.dart';
 import 'name_scheme.dart';
 import 'source_class_builder.dart';
-import 'source_function_builder.dart';
 import 'source_library_builder.dart' show SourceLibraryBuilder;
 import 'source_loader.dart' show SourceLoader;
 import 'source_member_builder.dart';
@@ -76,7 +75,7 @@ abstract class SourceConstructorBuilder implements ConstructorBuilder {
 class SourceConstructorBuilderImpl extends SourceMemberBuilderImpl
     implements
         SourceConstructorBuilder,
-        SourceFunctionBuilder,
+        SourceMemberBuilder,
         Inferable,
         ConstructorDeclarationBuilder {
   final Modifiers modifiers;
@@ -169,13 +168,14 @@ class SourceConstructorBuilderImpl extends SourceMemberBuilderImpl
   @override
   Builder get parent => declarationBuilder;
 
-  @override
+  bool get hasParameters => _introductory.formals != null;
+
   // Coverage-ignore(suite): Not run.
-  List<NominalParameterBuilder>? get typeParameters =>
+  List<NominalParameterBuilder>? get typeParametersForTesting =>
       _introductory.typeParameters;
 
-  @override
-  List<FormalParameterBuilder>? get formals => _introductory.formals;
+  // Coverage-ignore(suite): Not run.
+  List<FormalParameterBuilder>? get formalsForTesting => _introductory.formals;
 
   @override
   // Coverage-ignore(suite): Not run.
@@ -210,20 +210,12 @@ class SourceConstructorBuilderImpl extends SourceMemberBuilderImpl
   Name get memberName => _memberName.name;
 
   @override
+  // Coverage-ignore(suite): Not run.
   SourceConstructorBuilderImpl get origin => this;
 
   @override
   bool get isRedirecting => _lastDeclaration.isRedirecting;
 
-  @override
-  // Coverage-ignore(suite): Not run.
-  VariableDeclaration? get thisVariable => _introductory.thisVariable;
-
-  @override
-  // Coverage-ignore(suite): Not run.
-  List<TypeParameter>? get thisTypeParameters =>
-      _introductory.thisTypeParameters;
-
   @override
   Member get readTarget => _readTarget;
 
@@ -262,7 +254,6 @@ class SourceConstructorBuilderImpl extends SourceMemberBuilderImpl
   @override
   FunctionNode get function => _lastDeclaration.function;
 
-  @override
   void becomeNative(SourceLoader loader) {
     _introductory.becomeNative();
     for (ConstructorDeclaration augmentation in _augmentations) {
@@ -284,7 +275,6 @@ class SourceConstructorBuilderImpl extends SourceMemberBuilderImpl
 
   final String? nativeMethodName;
 
-  @override
   // Coverage-ignore(suite): Not run.
   bool get isNative => nativeMethodName != null;