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

// Copyright (c) 2024, 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.

import 'package:_fe_analyzer_shared/src/scanner/scanner.dart' show Token;
import 'package:kernel/ast.dart';
import 'package:kernel/reference_from_index.dart';

import '../base/scope.dart';
import '../builder/builder.dart';
import '../builder/constructor_reference_builder.dart';
import '../builder/declaration_builders.dart';
import '../builder/formal_parameter_builder.dart';
import '../builder/metadata_builder.dart';
import '../builder/mixin_application_builder.dart';
import '../builder/type_builder.dart';
import '../source/name_scheme.dart';
import '../source/source_class_builder.dart';
import '../source/source_constructor_builder.dart';
import '../source/source_enum_builder.dart';
import '../source/source_extension_builder.dart';
import '../source/source_extension_type_declaration_builder.dart';
import '../source/source_factory_builder.dart';
import '../source/source_field_builder.dart';
import '../source/source_procedure_builder.dart';
import '../source/source_type_alias_builder.dart';
import '../source/type_parameter_scope_builder.dart';

sealed class Fragment {
  Builder get builder;
}

class TypedefFragment implements Fragment {
  final List<MetadataBuilder>? metadata;
  final String name;
  final List<NominalVariableBuilder>? typeVariables;
  final TypeBuilder type;
  final Uri fileUri;
  final int fileOffset;
  final Reference? reference;

  SourceTypeAliasBuilder? _builder;

  TypedefFragment(
      {required this.metadata,
      required this.name,
      required this.typeVariables,
      required this.type,
      required this.fileUri,
      required this.fileOffset,
      required this.reference});

  @override
  // Coverage-ignore(suite): Not run.
  SourceTypeAliasBuilder get builder {
    assert(_builder != null, "Builder has not been computed for $this.");
    return _builder!;
  }

  void set builder(SourceTypeAliasBuilder value) {
    assert(_builder == null, "Builder has already been computed for $this.");
    _builder = value;
  }

  @override
  String toString() => "$runtimeType($name,$fileUri,$fileOffset)";
}

class ClassFragment extends DeclarationFragment implements Fragment {
  @override
  final String name;

  final int nameOffset;

  final ClassName _className;

  SourceClassBuilder? _builder;

  late final LookupScope compilationUnitScope;
  late final List<MetadataBuilder>? metadata;
  late final int modifiers;
  late final TypeBuilder? supertype;
  late final MixinApplicationBuilder? mixins;
  late final List<TypeBuilder>? interfaces;
  late final List<ConstructorReferenceBuilder> constructorReferences;
  late final int startOffset;
  late final int charOffset;
  late final int endOffset;
  late final IndexedLibrary? indexedLibrary;
  late final IndexedClass? indexedClass;
  late final bool isAugmentation;
  late final bool isBase;
  late final bool isFinal;
  late final bool isInterface;
  late final bool isMacro;
  late final bool isMixinClass;
  late final bool isSealed;

  ClassFragment(this.name, super.fileUri, this.nameOffset, super.typeParameters,
      super.typeParameterScope, super._nominalParameterNameSpace)
      : _className = new ClassName(name);

  @override
  int get fileOffset => nameOffset;

  @override
  SourceClassBuilder get builder {
    assert(_builder != null, "Builder has not been computed for $this.");
    return _builder!;
  }

  void set builder(SourceClassBuilder value) {
    assert(_builder == null, "Builder has already been computed for $this.");
    _builder = value;
  }

  @override
  ContainerName get containerName => _className;

  @override
  ContainerType get containerType => ContainerType.Class;

  @override
  DeclarationFragmentKind get kind => DeclarationFragmentKind.classDeclaration;

  @override
  String toString() => '$runtimeType($name,$fileUri,$fileOffset)';
}

class MixinFragment extends DeclarationFragment implements Fragment {
  @override
  final String name;

  final int nameOffset;

  final ClassName _className;

  SourceClassBuilder? _builder;

  late final LookupScope compilationUnitScope;
  late final List<MetadataBuilder>? metadata;
  late final int modifiers;
  late final TypeBuilder? supertype;
  late final MixinApplicationBuilder? mixins;
  late final List<TypeBuilder>? interfaces;
  late final List<ConstructorReferenceBuilder> constructorReferences;
  late final int startOffset;
  late final int charOffset;
  late final int endOffset;
  late final IndexedLibrary? indexedLibrary;
  late final IndexedClass? indexedClass;
  late final bool isAugmentation;
  late final bool isBase;

  MixinFragment(this.name, super.fileUri, this.nameOffset, super.typeParameters,
      super.typeParameterScope, super._nominalParameterNameSpace)
      : _className = new ClassName(name);

  @override
  int get fileOffset => nameOffset;

  @override
  SourceClassBuilder get builder {
    assert(_builder != null, "Builder has not been computed for $this.");
    return _builder!;
  }

  void set builder(SourceClassBuilder value) {
    assert(_builder == null, "Builder has already been computed for $this.");
    _builder = value;
  }

  @override
  ContainerName get containerName => _className;

  @override
  ContainerType get containerType => ContainerType.Class;

  @override
  DeclarationFragmentKind get kind => DeclarationFragmentKind.mixinDeclaration;

  @override
  String toString() => '$runtimeType($name,$fileUri,$fileOffset)';
}

class NamedMixinApplicationFragment implements Fragment {
  final String name;
  final Uri fileUri;
  final int startCharOffset;
  final int charOffset;
  final int charEndOffset;
  final int modifiers;
  final List<MetadataBuilder>? metadata;
  final List<NominalVariableBuilder>? typeParameters;
  final TypeBuilder? supertype;
  final MixinApplicationBuilder mixins;
  final List<TypeBuilder>? interfaces;
  final bool isAugmentation;
  final bool isBase;
  final bool isFinal;
  final bool isInterface;
  final bool isMacro;
  final bool isMixinClass;
  final bool isSealed;
  final LookupScope compilationUnitScope;
  final IndexedLibrary? indexedLibrary;

  SourceClassBuilder? _builder;

  NamedMixinApplicationFragment(
      {required this.name,
      required this.fileUri,
      required this.startCharOffset,
      required this.charOffset,
      required this.charEndOffset,
      required this.modifiers,
      required this.metadata,
      required this.typeParameters,
      required this.supertype,
      required this.mixins,
      required this.interfaces,
      required this.isAugmentation,
      required this.isBase,
      required this.isFinal,
      required this.isInterface,
      required this.isMacro,
      required this.isMixinClass,
      required this.isSealed,
      required this.compilationUnitScope,
      required this.indexedLibrary});

  @override
  // Coverage-ignore(suite): Not run.
  SourceClassBuilder get builder {
    assert(_builder != null, "Builder has not been computed for $this.");
    return _builder!;
  }

  // Coverage-ignore(suite): Not run.
  void set builder(SourceClassBuilder value) {
    assert(_builder == null, "Builder has already been computed for $this.");
    _builder = value;
  }

  @override
  String toString() => '$runtimeType($name,$fileUri,$charOffset)';
}

class EnumFragment extends DeclarationFragment implements Fragment {
  @override
  final String name;

  final int nameOffset;

  final ClassName _className;

  SourceEnumBuilder? _builder;

  late final LookupScope compilationUnitScope;
  late final List<MetadataBuilder>? metadata;
  late final MixinApplicationBuilder? supertypeBuilder;
  late final List<TypeBuilder>? interfaces;
  late final List<EnumConstantInfo?>? enumConstantInfos;
  late final List<ConstructorReferenceBuilder> constructorReferences;
  late final int startCharOffset;
  late final int charOffset;
  late final int charEndOffset;
  late final IndexedLibrary? indexedLibrary;
  late final IndexedClass? indexedClass;

  EnumFragment(this.name, super.fileUri, this.nameOffset, super.typeParameters,
      super.typeParameterScope, super._nominalParameterNameSpace)
      : _className = new ClassName(name);

  @override
  int get fileOffset => nameOffset;

  @override
  SourceEnumBuilder get builder {
    assert(_builder != null, "Builder has not been computed for $this.");
    return _builder!;
  }

  void set builder(SourceEnumBuilder value) {
    assert(_builder == null, "Builder has already been computed for $this.");
    _builder = value;
  }

  @override
  ContainerName get containerName => _className;

  @override
  ContainerType get containerType => ContainerType.Class;

  @override
  DeclarationFragmentKind get kind => DeclarationFragmentKind.enumDeclaration;

  @override
  String toString() => '$runtimeType($name,$fileUri,$fileOffset)';
}

class ExtensionFragment extends DeclarationFragment implements Fragment {
  final ExtensionName extensionName;

  @override
  final int fileOffset;

  /// The type of `this` in instance methods declared in extension declarations.
  ///
  /// Instance methods declared in extension declarations methods are extended
  /// with a synthesized parameter of this type.
  TypeBuilder? _extensionThisType;

  SourceExtensionBuilder? _builder;

  late final List<MetadataBuilder>? metadata;
  late final int modifiers;
  late final TypeBuilder onType;
  late final int startOffset;
  late final int nameOffset;
  late final int endOffset;
  late final Reference? reference;

  ExtensionFragment(
      String? name,
      super.fileUri,
      this.fileOffset,
      super.typeParameters,
      super.typeParameterScope,
      super._nominalParameterNameSpace)
      : extensionName = name != null
            ? new FixedExtensionName(name)
            : new UnnamedExtensionName();

  @override
  SourceExtensionBuilder get builder {
    assert(_builder != null, "Builder has not been computed for $this.");
    return _builder!;
  }

  void set builder(SourceExtensionBuilder value) {
    assert(_builder == null, "Builder has already been computed for $this.");
    _builder = value;
  }

  @override
  String get name => extensionName.name;

  @override
  ContainerName get containerName => extensionName;

  @override
  ContainerType get containerType => ContainerType.Extension;

  @override
  DeclarationFragmentKind get kind =>
      DeclarationFragmentKind.extensionDeclaration;

  /// Registers the 'extension this type' of the extension declaration prepared
  /// for by this builder.
  ///
  /// See [extensionThisType] for terminology.
  void registerExtensionThisType(TypeBuilder type) {
    assert(_extensionThisType == null,
        "Extension this type has already been set.");
    _extensionThisType = type;
  }

  /// Returns the 'extension this type' of the extension declaration prepared
  /// for by this builder.
  ///
  /// The 'extension this type' is the type mentioned in the on-clause of the
  /// extension declaration. For instance `B` in this extension declaration:
  ///
  ///     extension A on B {
  ///       B method() => this;
  ///     }
  ///
  /// The 'extension this type' is the type if `this` expression in instance
  /// methods declared in extension declarations.
  TypeBuilder get extensionThisType {
    assert(_extensionThisType != null,
        "DeclarationBuilder.extensionThisType has not been set on $this.");
    return _extensionThisType!;
  }

  @override
  String toString() => '$runtimeType($name,$fileUri,$fileOffset)';
}

class ExtensionTypeFragment extends DeclarationFragment implements Fragment {
  @override
  final String name;

  final int nameOffset;

  final ClassName _className;

  late final List<MetadataBuilder>? metadata;
  late final int modifiers;
  late final List<TypeBuilder>? interfaces;
  late final List<ConstructorReferenceBuilder> constructorReferences;
  late final int startOffset;
  late final int endOffset;
  late final IndexedContainer? indexedContainer;

  SourceExtensionTypeDeclarationBuilder? _builder;

  ExtensionTypeFragment(
      this.name,
      super.fileUri,
      this.nameOffset,
      super.typeParameters,
      super.typeParameterScope,
      super._nominalParameterNameSpace)
      : _className = new ClassName(name);

  @override
  int get fileOffset => nameOffset;

  @override
  SourceExtensionTypeDeclarationBuilder get builder {
    assert(_builder != null, "Builder has not been computed for $this.");
    return _builder!;
  }

  void set builder(SourceExtensionTypeDeclarationBuilder value) {
    assert(_builder == null, "Builder has already been computed for $this.");
    _builder = value;
  }

  @override
  ContainerName get containerName => _className;

  @override
  ContainerType get containerType => ContainerType.ExtensionType;

  @override
  DeclarationFragmentKind get kind =>
      DeclarationFragmentKind.extensionTypeDeclaration;

  @override
  String toString() => '$runtimeType($name,$fileUri,$fileOffset)';
}

class FieldFragment implements Fragment {
  final String name;
  final Uri fileUri;
  final int charOffset;
  final int charEndOffset;
  Token? _initializerToken;
  Token? _constInitializerToken;
  final List<MetadataBuilder>? metadata;
  final TypeBuilder type;
  final Reference? fieldReference;
  final Reference? fieldGetterReference;
  final Reference? fieldSetterReference;
  final Reference? lateGetterReference;
  final Reference? lateSetterReference;
  final Reference? lateIsSetFieldReference;
  final Reference? lateIsSetGetterReference;
  final Reference? lateIsSetSetterReference;
  final bool isTopLevel;
  final int modifiers;
  final NameScheme nameScheme;

  SourceFieldBuilder? _builder;

  FieldFragment(
      {required this.name,
      required this.fileUri,
      required this.charOffset,
      required this.charEndOffset,
      required Token? initializerToken,
      required Token? constInitializerToken,
      required this.metadata,
      required this.type,
      required this.fieldReference,
      required this.fieldGetterReference,
      required this.fieldSetterReference,
      required this.lateGetterReference,
      required this.lateSetterReference,
      required this.lateIsSetFieldReference,
      required this.lateIsSetGetterReference,
      required this.lateIsSetSetterReference,
      required this.isTopLevel,
      required this.modifiers,
      required this.nameScheme})
      : _initializerToken = initializerToken,
        _constInitializerToken = constInitializerToken;

  Token? get initializerToken {
    Token? result = _initializerToken;
    // Ensure that we don't hold onto the token.
    _initializerToken = null;
    return result;
  }

  Token? get constInitializerToken {
    Token? result = _constInitializerToken;
    // Ensure that we don't hold onto the token.
    _constInitializerToken = null;
    return result;
  }

  @override
  SourceFieldBuilder get builder {
    assert(_builder != null, "Builder has not been computed for $this.");
    return _builder!;
  }

  void set builder(SourceFieldBuilder value) {
    assert(_builder == null, "Builder has already been computed for $this.");
    _builder = value;
  }

  @override
  String toString() => '$runtimeType($name,$fileUri,$charOffset)';
}

class MethodFragment implements Fragment {
  final String name;
  final Uri fileUri;
  final int startCharOffset;
  final int charOffset;
  final int charOpenParenOffset;
  final int charEndOffset;
  final List<MetadataBuilder>? metadata;
  final int modifiers;
  final TypeBuilder returnType;
  final List<NominalVariableBuilder>? typeParameters;
  final List<FormalParameterBuilder>? formals;
  final ProcedureKind kind;
  final Reference? procedureReference;
  final Reference? tearOffReference;
  final AsyncMarker asyncModifier;
  final NameScheme nameScheme;
  final String? nativeMethodName;

  SourceProcedureBuilder? _builder;

  MethodFragment(
      {required this.name,
      required this.fileUri,
      required this.startCharOffset,
      required this.charOffset,
      required this.charOpenParenOffset,
      required this.charEndOffset,
      required this.metadata,
      required this.modifiers,
      required this.returnType,
      required this.typeParameters,
      required this.formals,
      required this.kind,
      required this.procedureReference,
      required this.tearOffReference,
      required this.asyncModifier,
      required this.nameScheme,
      required this.nativeMethodName});

  @override
  SourceProcedureBuilder get builder {
    assert(_builder != null, "Builder has not been computed for $this.");
    return _builder!;
  }

  void set builder(SourceProcedureBuilder value) {
    assert(_builder == null, "Builder has already been computed for $this.");
    _builder = value;
  }

  @override
  String toString() => '$runtimeType($name,$fileUri,$charOffset)';
}

class ConstructorFragment implements Fragment {
  final String name;
  final Uri fileUri;
  final int startCharOffset;
  final int charOffset;
  final int charOpenParenOffset;
  final int charEndOffset;
  final int modifiers;
  final List<MetadataBuilder>? metadata;
  final OmittedTypeBuilder returnType;
  final List<NominalVariableBuilder>? typeParameters;
  final List<FormalParameterBuilder>? formals;
  final Reference? constructorReference;
  final Reference? tearOffReference;
  final NameScheme nameScheme;
  final String? nativeMethodName;
  final bool forAbstractClassOrMixin;
  Token? _beginInitializers;

  AbstractSourceConstructorBuilder? _builder;

  ConstructorFragment(
      {required this.name,
      required this.fileUri,
      required this.startCharOffset,
      required this.charOffset,
      required this.charOpenParenOffset,
      required this.charEndOffset,
      required this.modifiers,
      required this.metadata,
      required this.returnType,
      required this.typeParameters,
      required this.formals,
      required this.constructorReference,
      required this.tearOffReference,
      required this.nameScheme,
      required this.nativeMethodName,
      required this.forAbstractClassOrMixin,
      required Token? beginInitializers})
      : _beginInitializers = beginInitializers;

  Token? get beginInitializers {
    Token? result = _beginInitializers;
    // Ensure that we don't hold onto the token.
    _beginInitializers = null;
    return result;
  }

  @override
  AbstractSourceConstructorBuilder get builder {
    assert(_builder != null, "Builder has not been computed for $this.");
    return _builder!;
  }

  void set builder(AbstractSourceConstructorBuilder value) {
    assert(_builder == null, "Builder has already been computed for $this.");
    _builder = value;
  }

  @override
  String toString() => '$runtimeType($name,$fileUri,$charOffset)';
}

class FactoryFragment implements Fragment {
  final String name;
  final Uri fileUri;
  final int startCharOffset;
  final int charOffset;
  final int charOpenParenOffset;
  final int charEndOffset;
  final int modifiers;
  final List<MetadataBuilder>? metadata;
  final TypeBuilder returnType;
  final List<NominalVariableBuilder>? typeParameters;
  final List<FormalParameterBuilder>? formals;
  final Reference? constructorReference;
  final Reference? tearOffReference;
  final AsyncMarker asyncModifier;
  final NameScheme nameScheme;
  final String? nativeMethodName;
  final ConstructorReferenceBuilder? redirectionTarget;

  SourceFactoryBuilder? _builder;

  FactoryFragment(
      {required this.name,
      required this.fileUri,
      required this.startCharOffset,
      required this.charOffset,
      required this.charOpenParenOffset,
      required this.charEndOffset,
      required this.modifiers,
      required this.metadata,
      required this.returnType,
      required this.typeParameters,
      required this.formals,
      required this.constructorReference,
      required this.tearOffReference,
      required this.asyncModifier,
      required this.nameScheme,
      required this.nativeMethodName,
      required this.redirectionTarget});

  @override
  SourceFactoryBuilder get builder {
    assert(_builder != null, "Builder has not been computed for $this.");
    return _builder!;
  }

  void set builder(SourceFactoryBuilder value) {
    assert(_builder == null, "Builder has already been computed for $this.");
    _builder = value;
  }

  @override
  String toString() => '$runtimeType($name,$fileUri,$charOffset)';
}