pkg/front_end/lib/src/fasta/builder/class_builder.dart - sdk - Git at Google

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.

 library fasta.class_builder;

 import 'package:kernel/ast.dart'
     show
         Class,
         DartType,
         DynamicType,
         FutureOrType,
         InterfaceType,
         Member,
         Name,
         NullType,
         Nullability,
         Supertype,
         TreeNode,
         getAsTypeArguments;
 import 'package:kernel/class_hierarchy.dart'
     show ClassHierarchy, ClassHierarchyBase;
 import 'package:kernel/src/unaliasing.dart';

 import '../fasta_codes.dart';
 import '../modifier.dart';
 import '../problems.dart' show internalProblem, unhandled;
 import '../scope.dart';
 import '../source/source_library_builder.dart';
 import '../type_inference/type_schema.dart' show UnknownType;
 import 'builder.dart';
 import 'declaration_builder.dart';
 import 'library_builder.dart';
 import 'member_builder.dart';
 import 'metadata_builder.dart';
 import 'nullability_builder.dart';
 import 'type_builder.dart';
 import 'type_variable_builder.dart';

 const Uri? noUri = null;

 abstract class ClassBuilder implements DeclarationBuilder {
   /// The type variables declared on a class, extension or mixin declaration.
   List<TypeVariableBuilder>? get typeVariables;

   /// The type in the `extends` clause of a class declaration.
   ///
   /// Currently this also holds the synthesized super class for a mixin
   /// declaration.
   abstract TypeBuilder? supertypeBuilder;

   /// The type in the `implements` clause of a class or mixin declaration.
   abstract List<TypeBuilder>? interfaceBuilders;

   /// The types in the `on` clause of an extension or mixin declaration.
   List<TypeBuilder>? get onTypes;

   ConstructorScope get constructorScope;

   @override
   Uri get fileUri;

   bool get isAbstract;

   bool get isMacro;

   bool get isAugmentation;

   bool get declaresConstConstructor;

   bool get isMixin;

   bool get isMixinApplication;

   bool get isAnonymousMixinApplication;

   abstract TypeBuilder? mixedInTypeBuilder;

   MemberBuilder? findConstructorOrFactory(
       String name, int charOffset, Uri uri, LibraryBuilder accessingLibrary);

   void forEach(void f(String name, Builder builder));

   /// The [Class] built by this builder.
   ///
   /// For a patch class the origin class is returned.
   Class get cls;

   @override
   ClassBuilder get origin;

   abstract bool isNullClass;

   @override
   InterfaceType get thisType;

   InterfaceType get legacyRawType;

   InterfaceType get nullableRawType;

   InterfaceType get nonNullableRawType;

   InterfaceType rawType(Nullability nullability);

   List<DartType> buildAliasedTypeArguments(LibraryBuilder library,
       List<TypeBuilder>? arguments, ClassHierarchyBase? hierarchy);

   Supertype buildMixedInType(
       LibraryBuilder library, List<TypeBuilder>? arguments);

   /// Looks up the member by [name] on the class built by this class builder.
   ///
   /// If [isSetter] is `false`, only fields, methods, and getters with that name
   /// will be found.  If [isSetter] is `true`, only non-final fields and setters
   /// will be found.
   ///
   /// If [isSuper] is `false`, the member is found among the interface members
   /// the class built by this class builder. If [isSuper] is `true`, the member
   /// is found among the class members of the superclass.
   ///
   /// If this class builder is a patch, interface members declared in this
   /// patch are searched before searching the interface members in the origin
   /// class.
   Member? lookupInstanceMember(ClassHierarchy hierarchy, Name name,
       {bool isSetter = false, bool isSuper = false});

   /// Calls [f] for each constructor declared in this class.
   void forEachConstructor(void Function(String, MemberBuilder) f);
 }

 abstract class ClassBuilderImpl extends DeclarationBuilderImpl
     implements ClassBuilder {
   @override
   List<TypeVariableBuilder>? typeVariables;

   @override
   TypeBuilder? supertypeBuilder;

   @override
   List<TypeBuilder>? interfaceBuilders;

   @override
   List<TypeBuilder>? onTypes;

   @override
   final ConstructorScope constructorScope;

   @override
   bool isNullClass = false;

   InterfaceType? _legacyRawType;
   InterfaceType? _nullableRawType;
   InterfaceType? _nonNullableRawType;
   InterfaceType? _thisType;

   ClassBuilderImpl(
       List<MetadataBuilder>? metadata,
       int modifiers,
       String name,
       this.typeVariables,
       this.supertypeBuilder,
       this.interfaceBuilders,
       this.onTypes,
       Scope scope,
       this.constructorScope,
       LibraryBuilder parent,
       int charOffset)
       : super(metadata, modifiers, name, parent, charOffset, scope);

   @override
   String get debugName => "ClassBuilder";

   @override
   bool get isAbstract => (modifiers & abstractMask) != 0;

   @override
   bool get isMixin => (modifiers & mixinDeclarationMask) != 0;

   @override
   bool get isMixinApplication => mixedInTypeBuilder != null;

   @override
   bool get isNamedMixinApplication {
     return isMixinApplication && (modifiers & namedMixinApplicationMask) != 0;
   }

   @override
   bool get isAnonymousMixinApplication {
     return isMixinApplication && !isNamedMixinApplication;
   }

   @override
   bool get declaresConstConstructor =>
       (modifiers & declaresConstConstructorMask) != 0;

   @override
   Builder? findStaticBuilder(
       String name, int charOffset, Uri fileUri, LibraryBuilder accessingLibrary,
       {bool isSetter = false}) {
     if (accessingLibrary.nameOriginBuilder.origin !=
             libraryBuilder.nameOriginBuilder.origin &&
         name.startsWith("_")) {
       return null;
     }
     Builder? declaration = isSetter
         ? scope.lookupSetter(name, charOffset, fileUri, isInstanceScope: false)
         : scope.lookup(name, charOffset, fileUri, isInstanceScope: false);
     if (declaration == null && isPatch) {
       return origin.findStaticBuilder(
           name, charOffset, fileUri, accessingLibrary,
           isSetter: isSetter);
     }
     return declaration;
   }

   @override
   MemberBuilder? findConstructorOrFactory(
       String name, int charOffset, Uri uri, LibraryBuilder accessingLibrary) {
     if (accessingLibrary.nameOriginBuilder.origin !=
             libraryBuilder.nameOriginBuilder.origin &&
         name.startsWith("_")) {
       return null;
     }
     MemberBuilder? declaration =
         constructorScope.lookup(name == 'new' ? '' : name, charOffset, uri);
     if (declaration == null && isPatch) {
       return origin.findConstructorOrFactory(
           name, charOffset, uri, accessingLibrary);
     }
     return declaration;
   }

   @override
   Builder? lookupLocalMember(String name,
       {bool setter = false, bool required = false}) {
     Builder? builder = scope.lookupLocalMember(name, setter: setter);
     if (builder == null && isPatch) {
       builder = origin.scope.lookupLocalMember(name, setter: setter);
     }
     if (required && builder == null) {
       internalProblem(
           templateInternalProblemNotFoundIn.withArguments(
               name, fullNameForErrors),
           -1,
           null);
     }
     return builder;
   }

   /// Find the first member of this class with [name]. This method isn't
   /// suitable for scope lookups as it will throw an error if the name isn't
   /// declared. The [scope] should be used for that. This method is used to
   /// find a member that is known to exist and it will pick the first
   /// declaration if the name is ambiguous.
   ///
   /// For example, this method is convenient for use when building synthetic
   /// members, such as those of an enum.
   MemberBuilder? firstMemberNamed(String name) {
     MemberBuilder declaration =
         lookupLocalMember(name, required: true) as MemberBuilder;
     while (declaration.next != null) {
       declaration = declaration.next as MemberBuilder;
     }
     return declaration;
   }

   @override
   InterfaceType get thisType {
     return _thisType ??= new InterfaceType(cls, libraryBuilder.nonNullable,
         getAsTypeArguments(cls.typeParameters, libraryBuilder.library));
   }

   @override
   InterfaceType get legacyRawType {
     return _legacyRawType ??= new InterfaceType(cls, Nullability.legacy,
         new List<DartType>.filled(typeVariablesCount, const DynamicType()));
   }

   @override
   InterfaceType get nullableRawType {
     return _nullableRawType ??= new InterfaceType(cls, Nullability.nullable,
         new List<DartType>.filled(typeVariablesCount, const DynamicType()));
   }

   @override
   InterfaceType get nonNullableRawType {
     return _nonNullableRawType ??= new InterfaceType(
         cls,
         Nullability.nonNullable,
         new List<DartType>.filled(typeVariablesCount, const DynamicType()));
   }

   @override
   InterfaceType rawType(Nullability nullability) {
     switch (nullability) {
       case Nullability.legacy:
         return legacyRawType;
       case Nullability.nullable:
         return nullableRawType;
       case Nullability.nonNullable:
         return nonNullableRawType;
       case Nullability.undetermined:
       default:
         return unhandled("$nullability", "rawType", TreeNode.noOffset, noUri);
     }
   }

   @override
   DartType buildAliasedTypeWithBuiltArguments(
       LibraryBuilder library,
       Nullability nullability,
       List<DartType>? arguments,
       TypeUse typeUse,
       Uri fileUri,
       int charOffset,
       {required bool hasExplicitTypeArguments}) {
     assert(arguments == null || cls.typeParameters.length == arguments.length);
     if (isNullClass) {
       return const NullType();
     }
     if (name == "FutureOr") {
       LibraryBuilder parentLibrary = parent as LibraryBuilder;
       if (parentLibrary.importUri.isScheme("dart") &&
           parentLibrary.importUri.path == "async") {
         assert(arguments != null && arguments.length == 1);
         return new FutureOrType(arguments!.single, nullability);
       }
     }
     DartType type = arguments == null
         ? rawType(nullability)
         : new InterfaceType(cls, nullability, arguments);
     if (typeVariablesCount != 0 && library is SourceLibraryBuilder) {
       library.registerBoundsCheck(type, fileUri, charOffset, typeUse,
           inferred: !hasExplicitTypeArguments);
     }
     return type;
   }

   @override
   DartType buildAliasedType(
       LibraryBuilder library,
       NullabilityBuilder nullabilityBuilder,
       List<TypeBuilder>? arguments,
       TypeUse typeUse,
       Uri fileUri,
       int charOffset,
       ClassHierarchyBase? hierarchy,
       {required bool hasExplicitTypeArguments}) {
     return buildAliasedTypeWithBuiltArguments(
         library,
         nullabilityBuilder.build(library),
         buildAliasedTypeArguments(library, arguments, hierarchy),
         typeUse,
         fileUri,
         charOffset,
         hasExplicitTypeArguments: hasExplicitTypeArguments);
   }

   @override
   Supertype buildMixedInType(
       LibraryBuilder library, List<TypeBuilder>? arguments) {
     Class cls = isPatch ? origin.cls : this.cls;
     if (arguments != null) {
       List<DartType> typeArguments =
           buildAliasedTypeArguments(library, arguments, /* hierarchy = */ null);
       typeArguments = unaliasTypes(typeArguments,
           legacyEraseAliases: !library.isNonNullableByDefault)!;
       return new Supertype(cls, typeArguments);
     } else {
       return new Supertype(
           cls,
           new List<DartType>.filled(
               cls.typeParameters.length, const UnknownType(),
               growable: true));
     }
   }

   @override
   String get fullNameForErrors {
     return isMixinApplication && !isNamedMixinApplication
         ? "${supertypeBuilder!.fullNameForErrors} with "
             "${mixedInTypeBuilder!.fullNameForErrors}"
         : name;
   }

   @override
   Member? lookupInstanceMember(ClassHierarchy hierarchy, Name name,
       {bool isSetter = false, bool isSuper = false}) {
     Class? instanceClass = cls;
     if (isPatch) {
       assert(identical(instanceClass, origin.cls),
           "Found ${origin.cls} expected $instanceClass");
       if (isSuper) {
         // The super class is only correctly found through the origin class.
         instanceClass = origin.cls;
       } else {
         Member? member =
             hierarchy.getInterfaceMember(instanceClass, name, setter: isSetter);
         if (member?.parent == instanceClass) {
           // Only if the member is found in the patch can we use it.
           return member;
         } else {
           // Otherwise, we need to keep searching in the origin class.
           instanceClass = origin.cls;
         }
       }
     }

     if (isSuper) {
       instanceClass = instanceClass.superclass;
       if (instanceClass == null) return null;
     }
     Member? target = isSuper
         ? hierarchy.getDispatchTarget(instanceClass, name, setter: isSetter)
         : hierarchy.getInterfaceMember(instanceClass, name, setter: isSetter);
     if (isSuper && target == null) {
       if (cls.isMixinDeclaration) {
         target =
             hierarchy.getInterfaceMember(instanceClass, name, setter: isSetter);
       }
     }
     return target;
   }
 }

 class ConstructorRedirection {
   String target;
   bool cycleReported;

   ConstructorRedirection(this.target) : cycleReported = false;
 }
	// Copyright (c) 2016, the Dart project authors. Please see the AUTHORS file
	// for details. All rights reserved. Use of this source code is governed by a
	// BSD-style license that can be found in the LICENSE file.

	library fasta.class_builder;

	import 'package:kernel/ast.dart'
	show
	Class,
	DartType,
	DynamicType,
	FutureOrType,
	InterfaceType,
	Member,
	Name,
	NullType,
	Nullability,
	Supertype,
	TreeNode,
	getAsTypeArguments;
	import 'package:kernel/class_hierarchy.dart'
	show ClassHierarchy, ClassHierarchyBase;
	import 'package:kernel/src/unaliasing.dart';

	import '../fasta_codes.dart';
	import '../modifier.dart';
	import '../problems.dart' show internalProblem, unhandled;
	import '../scope.dart';
	import '../source/source_library_builder.dart';
	import '../type_inference/type_schema.dart' show UnknownType;
	import 'builder.dart';
	import 'declaration_builder.dart';
	import 'library_builder.dart';
	import 'member_builder.dart';
	import 'metadata_builder.dart';
	import 'nullability_builder.dart';
	import 'type_builder.dart';
	import 'type_variable_builder.dart';

	const Uri? noUri = null;

	abstract class ClassBuilder implements DeclarationBuilder {
	/// The type variables declared on a class, extension or mixin declaration.
	List<TypeVariableBuilder>? get typeVariables;

	/// The type in the `extends` clause of a class declaration.
	///
	/// Currently this also holds the synthesized super class for a mixin
	/// declaration.
	abstract TypeBuilder? supertypeBuilder;

	/// The type in the `implements` clause of a class or mixin declaration.
	abstract List<TypeBuilder>? interfaceBuilders;

	/// The types in the `on` clause of an extension or mixin declaration.
	List<TypeBuilder>? get onTypes;

	ConstructorScope get constructorScope;

	@override
	Uri get fileUri;

	bool get isAbstract;

	bool get isMacro;

	bool get isAugmentation;

	bool get declaresConstConstructor;

	bool get isMixin;

	bool get isMixinApplication;

	bool get isAnonymousMixinApplication;

	abstract TypeBuilder? mixedInTypeBuilder;

	MemberBuilder? findConstructorOrFactory(
	String name, int charOffset, Uri uri, LibraryBuilder accessingLibrary);

	void forEach(void f(String name, Builder builder));

	/// The [Class] built by this builder.
	///
	/// For a patch class the origin class is returned.
	Class get cls;

	@override
	ClassBuilder get origin;

	abstract bool isNullClass;

	@override
	InterfaceType get thisType;

	InterfaceType get legacyRawType;

	InterfaceType get nullableRawType;

	InterfaceType get nonNullableRawType;

	InterfaceType rawType(Nullability nullability);

	List<DartType> buildAliasedTypeArguments(LibraryBuilder library,
	List<TypeBuilder>? arguments, ClassHierarchyBase? hierarchy);

	Supertype buildMixedInType(
	LibraryBuilder library, List<TypeBuilder>? arguments);

	/// Looks up the member by [name] on the class built by this class builder.
	///
	/// If [isSetter] is `false`, only fields, methods, and getters with that name
	/// will be found. If [isSetter] is `true`, only non-final fields and setters
	/// will be found.
	///
	/// If [isSuper] is `false`, the member is found among the interface members
	/// the class built by this class builder. If [isSuper] is `true`, the member
	/// is found among the class members of the superclass.
	///
	/// If this class builder is a patch, interface members declared in this
	/// patch are searched before searching the interface members in the origin
	/// class.
	Member? lookupInstanceMember(ClassHierarchy hierarchy, Name name,
	{bool isSetter = false, bool isSuper = false});

	/// Calls [f] for each constructor declared in this class.
	void forEachConstructor(void Function(String, MemberBuilder) f);
	}

	abstract class ClassBuilderImpl extends DeclarationBuilderImpl
	implements ClassBuilder {
	@override
	List<TypeVariableBuilder>? typeVariables;

	@override
	TypeBuilder? supertypeBuilder;

	@override
	List<TypeBuilder>? interfaceBuilders;

	@override
	List<TypeBuilder>? onTypes;

	@override
	final ConstructorScope constructorScope;

	@override
	bool isNullClass = false;

	InterfaceType? _legacyRawType;
	InterfaceType? _nullableRawType;
	InterfaceType? _nonNullableRawType;
	InterfaceType? _thisType;

	ClassBuilderImpl(
	List<MetadataBuilder>? metadata,
	int modifiers,
	String name,
	this.typeVariables,
	this.supertypeBuilder,
	this.interfaceBuilders,
	this.onTypes,
	Scope scope,
	this.constructorScope,
	LibraryBuilder parent,
	int charOffset)
	: super(metadata, modifiers, name, parent, charOffset, scope);

	@override
	String get debugName => "ClassBuilder";

	@override
	bool get isAbstract => (modifiers & abstractMask) != 0;

	@override
	bool get isMixin => (modifiers & mixinDeclarationMask) != 0;

	@override
	bool get isMixinApplication => mixedInTypeBuilder != null;

	@override
	bool get isNamedMixinApplication {
	return isMixinApplication && (modifiers & namedMixinApplicationMask) != 0;
	}

	@override
	bool get isAnonymousMixinApplication {
	return isMixinApplication && !isNamedMixinApplication;
	}

	@override
	bool get declaresConstConstructor =>
	(modifiers & declaresConstConstructorMask) != 0;

	@override
	Builder? findStaticBuilder(
	String name, int charOffset, Uri fileUri, LibraryBuilder accessingLibrary,
	{bool isSetter = false}) {
	if (accessingLibrary.nameOriginBuilder.origin !=
	libraryBuilder.nameOriginBuilder.origin &&
	name.startsWith("_")) {
	return null;
	}
	Builder? declaration = isSetter
	? scope.lookupSetter(name, charOffset, fileUri, isInstanceScope: false)
	: scope.lookup(name, charOffset, fileUri, isInstanceScope: false);
	if (declaration == null && isPatch) {
	return origin.findStaticBuilder(
	name, charOffset, fileUri, accessingLibrary,
	isSetter: isSetter);
	}
	return declaration;
	}

	@override
	MemberBuilder? findConstructorOrFactory(
	String name, int charOffset, Uri uri, LibraryBuilder accessingLibrary) {
	if (accessingLibrary.nameOriginBuilder.origin !=
	libraryBuilder.nameOriginBuilder.origin &&
	name.startsWith("_")) {
	return null;
	}
	MemberBuilder? declaration =
	constructorScope.lookup(name == 'new' ? '' : name, charOffset, uri);
	if (declaration == null && isPatch) {
	return origin.findConstructorOrFactory(
	name, charOffset, uri, accessingLibrary);
	}
	return declaration;
	}

	@override
	Builder? lookupLocalMember(String name,
	{bool setter = false, bool required = false}) {
	Builder? builder = scope.lookupLocalMember(name, setter: setter);
	if (builder == null && isPatch) {
	builder = origin.scope.lookupLocalMember(name, setter: setter);
	}
	if (required && builder == null) {
	internalProblem(
	templateInternalProblemNotFoundIn.withArguments(
	name, fullNameForErrors),
	-1,
	null);
	}
	return builder;
	}

	/// Find the first member of this class with [name]. This method isn't
	/// suitable for scope lookups as it will throw an error if the name isn't
	/// declared. The [scope] should be used for that. This method is used to
	/// find a member that is known to exist and it will pick the first
	/// declaration if the name is ambiguous.
	///
	/// For example, this method is convenient for use when building synthetic
	/// members, such as those of an enum.
	MemberBuilder? firstMemberNamed(String name) {
	MemberBuilder declaration =
	lookupLocalMember(name, required: true) as MemberBuilder;
	while (declaration.next != null) {
	declaration = declaration.next as MemberBuilder;
	}
	return declaration;
	}

	@override
	InterfaceType get thisType {
	return _thisType ??= new InterfaceType(cls, libraryBuilder.nonNullable,
	getAsTypeArguments(cls.typeParameters, libraryBuilder.library));
	}

	@override
	InterfaceType get legacyRawType {
	return _legacyRawType ??= new InterfaceType(cls, Nullability.legacy,
	new List<DartType>.filled(typeVariablesCount, const DynamicType()));
	}

	@override
	InterfaceType get nullableRawType {
	return _nullableRawType ??= new InterfaceType(cls, Nullability.nullable,
	new List<DartType>.filled(typeVariablesCount, const DynamicType()));
	}

	@override
	InterfaceType get nonNullableRawType {
	return _nonNullableRawType ??= new InterfaceType(
	cls,
	Nullability.nonNullable,
	new List<DartType>.filled(typeVariablesCount, const DynamicType()));
	}

	@override
	InterfaceType rawType(Nullability nullability) {
	switch (nullability) {
	case Nullability.legacy:
	return legacyRawType;
	case Nullability.nullable:
	return nullableRawType;
	case Nullability.nonNullable:
	return nonNullableRawType;
	case Nullability.undetermined:
	default:
	return unhandled("$nullability", "rawType", TreeNode.noOffset, noUri);
	}
	}

	@override
	DartType buildAliasedTypeWithBuiltArguments(
	LibraryBuilder library,
	Nullability nullability,
	List<DartType>? arguments,
	TypeUse typeUse,
	Uri fileUri,
	int charOffset,
	{required bool hasExplicitTypeArguments}) {
	assert(arguments == null \|\| cls.typeParameters.length == arguments.length);
	if (isNullClass) {
	return const NullType();
	}
	if (name == "FutureOr") {
	LibraryBuilder parentLibrary = parent as LibraryBuilder;
	if (parentLibrary.importUri.isScheme("dart") &&
	parentLibrary.importUri.path == "async") {
	assert(arguments != null && arguments.length == 1);
	return new FutureOrType(arguments!.single, nullability);
	}
	}
	DartType type = arguments == null
	? rawType(nullability)
	: new InterfaceType(cls, nullability, arguments);
	if (typeVariablesCount != 0 && library is SourceLibraryBuilder) {
	library.registerBoundsCheck(type, fileUri, charOffset, typeUse,
	inferred: !hasExplicitTypeArguments);
	}
	return type;
	}

	@override
	DartType buildAliasedType(
	LibraryBuilder library,
	NullabilityBuilder nullabilityBuilder,
	List<TypeBuilder>? arguments,
	TypeUse typeUse,
	Uri fileUri,
	int charOffset,
	ClassHierarchyBase? hierarchy,
	{required bool hasExplicitTypeArguments}) {
	return buildAliasedTypeWithBuiltArguments(
	library,
	nullabilityBuilder.build(library),
	buildAliasedTypeArguments(library, arguments, hierarchy),
	typeUse,
	fileUri,
	charOffset,
	hasExplicitTypeArguments: hasExplicitTypeArguments);
	}

	@override
	Supertype buildMixedInType(
	LibraryBuilder library, List<TypeBuilder>? arguments) {
	Class cls = isPatch ? origin.cls : this.cls;
	if (arguments != null) {
	List<DartType> typeArguments =
	buildAliasedTypeArguments(library, arguments, /* hierarchy = */ null);
	typeArguments = unaliasTypes(typeArguments,
	legacyEraseAliases: !library.isNonNullableByDefault)!;
	return new Supertype(cls, typeArguments);
	} else {
	return new Supertype(
	cls,
	new List<DartType>.filled(
	cls.typeParameters.length, const UnknownType(),
	growable: true));
	}
	}

	@override
	String get fullNameForErrors {
	return isMixinApplication && !isNamedMixinApplication
	? "${supertypeBuilder!.fullNameForErrors} with "
	"${mixedInTypeBuilder!.fullNameForErrors}"
	: name;
	}

	@override
	Member? lookupInstanceMember(ClassHierarchy hierarchy, Name name,
	{bool isSetter = false, bool isSuper = false}) {
	Class? instanceClass = cls;
	if (isPatch) {
	assert(identical(instanceClass, origin.cls),
	"Found ${origin.cls} expected $instanceClass");
	if (isSuper) {
	// The super class is only correctly found through the origin class.
	instanceClass = origin.cls;
	} else {
	Member? member =
	hierarchy.getInterfaceMember(instanceClass, name, setter: isSetter);
	if (member?.parent == instanceClass) {
	// Only if the member is found in the patch can we use it.
	return member;
	} else {
	// Otherwise, we need to keep searching in the origin class.
	instanceClass = origin.cls;
	}
	}
	}

	if (isSuper) {
	instanceClass = instanceClass.superclass;
	if (instanceClass == null) return null;
	}
	Member? target = isSuper
	? hierarchy.getDispatchTarget(instanceClass, name, setter: isSetter)
	: hierarchy.getInterfaceMember(instanceClass, name, setter: isSetter);
	if (isSuper && target == null) {
	if (cls.isMixinDeclaration) {
	target =
	hierarchy.getInterfaceMember(instanceClass, name, setter: isSetter);
	}
	}
	return target;
	}
	}

	class ConstructorRedirection {
	String target;
	bool cycleReported;

	ConstructorRedirection(this.target) : cycleReported = false;
	}