src/Workspaces/SharedUtilitiesAndExtensions/Workspace/CSharp/SemanticModelReuse/CSharpSemanticModelReuseLanguageService.cs - main - githubmirror/roslyn

src/Workspaces/SharedUtilitiesAndExtensions/Workspace/CSharp/SemanticModelReuse/CSharpSemanticModelReuseLanguageService.cs

74 строки3 KB

Cyrus Najmabadi

Fix layering of semantic model reuse service

21 июн 2025, 00:45

21 июн 2025, 00:454b467df

// 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;
using System.Composition;
using Microsoft.CodeAnalysis.CSharp.LanguageService;
using Microsoft.CodeAnalysis.CSharp.Syntax;
using Microsoft.CodeAnalysis.Host.Mef;
using Microsoft.CodeAnalysis.LanguageService;
using Microsoft.CodeAnalysis.SemanticModelReuse;

namespace Microsoft.CodeAnalysis.CSharp.SemanticModelReuse;

[ExportLanguageService(typeof(ISemanticModelReuseLanguageService), LanguageNames.CSharp), Shared]
internal sealed class CSharpSemanticModelReuseLanguageService : AbstractSemanticModelReuseLanguageService<
    MemberDeclarationSyntax,
    BasePropertyDeclarationSyntax,
    AccessorDeclarationSyntax>
{
    [ImportingConstructor]
    [Obsolete(MefConstruction.ImportingConstructorMessage, error: true)]
    public CSharpSemanticModelReuseLanguageService()
    {
    }

    protected override ISyntaxFacts SyntaxFacts => CSharpSyntaxFacts.Instance;

    protected override BasePropertyDeclarationSyntax GetBasePropertyDeclaration(AccessorDeclarationSyntax accessor)
    {
        Contract.ThrowIfFalse(accessor.Parent is AccessorListSyntax);
        Contract.ThrowIfFalse(accessor.Parent.Parent is BasePropertyDeclarationSyntax);
        return (BasePropertyDeclarationSyntax)accessor.Parent.Parent;
    }

    protected override SyntaxList<AccessorDeclarationSyntax> GetAccessors(BasePropertyDeclarationSyntax baseProperty)
        => baseProperty.AccessorList!.Accessors;

    public override SyntaxNode? TryGetContainingMethodBodyForSpeculation(SyntaxNode node)
    {
        for (SyntaxNode? previous = null, current = node; current != null; previous = current, current = current.Parent)
        {
            // These are the exact types that SemanticModel.TryGetSpeculativeSemanticModelForMethodBody accepts.
            if (current is BaseMethodDeclarationSyntax baseMethod)
                return previous != null && baseMethod.Body == previous ? baseMethod : null;

            if (current is AccessorDeclarationSyntax accessor)
                return previous != null && accessor.Body == previous ? accessor : null;
        }

        return null;
    }

    protected override SemanticModel? TryGetSpeculativeSemanticModelWorker(SemanticModel previousSemanticModel, SyntaxNode previousBodyNode, SyntaxNode currentBodyNode)
    {
        if (previousBodyNode is BaseMethodDeclarationSyntax previousBaseMethod &&
            currentBodyNode is BaseMethodDeclarationSyntax currentBaseMethod &&
            previousBaseMethod.Body != null &&
            previousSemanticModel.TryGetSpeculativeSemanticModelForMethodBody(previousBaseMethod.Body.SpanStart, currentBaseMethod, out var speculativeModel))
        {
            return speculativeModel;
        }

        if (previousBodyNode is AccessorDeclarationSyntax previousAccessorDeclaration &&
            currentBodyNode is AccessorDeclarationSyntax currentAccessorDeclaration &&
            previousAccessorDeclaration.Body != null &&
            previousSemanticModel.TryGetSpeculativeSemanticModelForMethodBody(previousAccessorDeclaration.Body.SpanStart, currentAccessorDeclaration, out speculativeModel))
        {
            return speculativeModel;
        }

        return null;
    }
}