// Licensed to the .NET Foundation under one or more agreements. // The .NET Foundation licenses this file to you under the MIT license. // See the LICENSE file in the project root for more information. using System.Collections.Immutable; using System.Linq; using System.Threading; using System.Threading.Tasks; using Microsoft.CodeAnalysis.CodeActions; using Microsoft.CodeAnalysis.CodeGeneration; using Microsoft.CodeAnalysis.Editing; using Microsoft.CodeAnalysis.PooledObjects; using Microsoft.CodeAnalysis.Shared.Extensions; using Roslyn.Utilities; namespace Microsoft.CodeAnalysis.GenerateConstructorFromMembers; internal abstract partial class AbstractGenerateConstructorFromMembersCodeRefactoringProvider { private sealed class ConstructorDelegatingCodeAction( AbstractGenerateConstructorFromMembersCodeRefactoringProvider service, Document document, State state, bool addNullChecks) : CodeAction { private readonly AbstractGenerateConstructorFromMembersCodeRefactoringProvider _service = service; private readonly Document _document = document; private readonly State _state = state; private readonly bool _addNullChecks = addNullChecks; protected override async Task<Document> GetChangedDocumentAsync(CancellationToken cancellationToken) { // First, see if there are any constructors that would take the first 'n' arguments // we've provided. If so, delegate to those, and then create a field for any // remaining arguments. Try to match from largest to smallest. // // Otherwise, just generate a normal constructor that assigns any provided // parameters into fields. var project = _document.Project; var languageServices = project.Solution.Services.GetLanguageServices(_state.ContainingType.Language); var semanticModel = await _document.GetRequiredSemanticModelAsync(cancellationToken).ConfigureAwait(false); var factory = languageServices.GetRequiredService<SyntaxGenerator>(); var codeGenerationService = languageServices.GetRequiredService<ICodeGenerationService>(); Contract.ThrowIfNull(_state.DelegatedConstructor); var thisConstructorArguments = factory.CreateArguments( _state.Parameters.Take(_state.DelegatedConstructor.Parameters.Length).ToImmutableArray()); using var _1 = ArrayBuilder<SyntaxNode>.GetInstance(out var nullCheckStatements); using var _2 = ArrayBuilder<SyntaxNode>.GetInstance(out var assignStatements); var useThrowExpressions = await _service.PrefersThrowExpressionAsync(_document, cancellationToken).ConfigureAwait(false); for (var i = _state.DelegatedConstructor.Parameters.Length; i < _state.Parameters.Length; i++) { var symbolName = _state.SelectedMembers[i].Name; var parameter = _state.Parameters[i]; var fieldAccess = factory.MemberAccessExpression( factory.ThisExpression(), factory.IdentifierName(symbolName)); factory.AddAssignmentStatements( factory.SyntaxGeneratorInternal, semanticModel, parameter, fieldAccess, _addNullChecks, useThrowExpressions, nullCheckStatements, assignStatements); } var syntaxTree = await _document.GetRequiredSyntaxTreeAsync(cancellationToken).ConfigureAwait(false); // If the user has selected a set of members (i.e. TextSpan is not empty), then we will // choose the right location (i.e. null) to insert the constructor. However, if they're // just invoking the feature manually at a specific location, then we'll insert the // members at that specific place in the class/struct. var afterThisLocation = _state.TextSpan.IsEmpty ? syntaxTree.GetLocation(_state.TextSpan) : null; var statements = nullCheckStatements.ToImmutable().Concat(assignStatements.ToImmutable()); var result = await codeGenerationService.AddMethodAsync( new CodeGenerationSolutionContext( _document.Project.Solution, new CodeGenerationContext( contextLocation: syntaxTree.GetLocation(_state.TextSpan), afterThisLocation: afterThisLocation)), _state.ContainingType, CodeGenerationSymbolFactory.CreateConstructorSymbol( attributes: default, accessibility: _state.ContainingType.IsAbstractClass() ? Accessibility.Protected : Accessibility.Public, modifiers: new DeclarationModifiers(), typeName: _state.ContainingType.Name, parameters: _state.Parameters, statements: statements, thisConstructorArguments: thisConstructorArguments), cancellationToken: cancellationToken).ConfigureAwait(false); return await AddNavigationAnnotationAsync(result, cancellationToken).ConfigureAwait(false); } public override string Title { get { var parameters = _state.Parameters.Select(p => _service.ToDisplayString(p, SimpleFormat)); var parameterString = string.Join(", ", parameters); return string.Format(FeaturesResources.Generate_delegating_constructor_0_1, _state.ContainingType.Name, parameterString); } } } } |