[Sonic] Support multiple C# documents in Rename

src/Razor/src/Razor/src/Microsoft.CodeAnalysis.Remote.Razor/DocumentMapping/RazorEditService_WorkspaceEdit.cs

@@ -13,6 +13,7 @@
 using Microsoft.CodeAnalysis.Razor;
 using Microsoft.CodeAnalysis.Razor.ProjectSystem;
 using Microsoft.CodeAnalysis.Remote.Razor.ProjectSystem;
+using Microsoft.CodeAnalysis.Text;
 
 namespace Microsoft.CodeAnalysis.Remote.Razor.DocumentMapping;
 
@@ -33,6 +34,12 @@ public async Task MapWorkspaceEditAsync(IDocumentSnapshot contextDocumentSnapsho
                 if (edit.TryGetFirst(out var textDocumentEdit))
                 {
                     await MapTextDocumentEditAsync(originSnapshot, textDocumentEdit, cancellationToken).ConfigureAwait(false);
+
+                    // Roslyn may return edits that already target the real Razor document when it maps
+                    // source-generated documents itself. If both generated C# documents contribute the
+                    // same Razor edit, keep a single edit so applying the workspace edit doesn't fail
+                    // with overlapping changes.
+                    await DeduplicateTextDocumentEditAsync(originSnapshot.TextDocument.Project.Solution, textDocumentEdit, cancellationToken).ConfigureAwait(false);
                     if (textDocumentEdit.Edits.Length == 0)
                     {
                         continue;
@@ -160,6 +167,71 @@ private async Task<ImmutableArray<TextEdit>> GetMappedTextEditsAsync(RemoteDocum
         var textChanges = edits.SelectAsArray(csharpSourceText.GetRazorTextChange);
         var mappedEdits = await MapCSharpEditsAsync(textChanges, snapshot, csharpDocument.IsDeclarationDocument, includeCSharpLanguageFeatureEdits: true, directlyMappedEditFilter: null, cancellationToken).ConfigureAwait(false);
 
-        return mappedEdits.SelectAsArray(razorSourceText.GetTextEdit);
+        // Multiple generated C# edits can map to the same Razor span, especially when rename touches
+        // both implementation and declaration generated documents. SourceText.WithChanges treats exact
+        // duplicate edits as overlapping, so collapse them after mapping back to Razor coordinates.
+        return Deduplicate(razorSourceText, mappedEdits.SelectAsArray(razorSourceText.GetTextEdit));
+    }
+
+    private static async Task DeduplicateTextDocumentEditAsync(Solution solution, TextDocumentEdit entry, CancellationToken cancellationToken)
+    {
+        if (entry.Edits.Length <= 1)
+        {
+            return;
+        }
+
+        var document = await solution.GetTextDocumentAsync(entry.TextDocument, cancellationToken).ConfigureAwait(false);
+        if (document is null)
+        {
+            return;
+        }
+
+        var sourceText = await document.GetTextAsync(cancellationToken).ConfigureAwait(false);
+        entry.Edits = Deduplicate(sourceText, entry.Edits);
+    }
+
+    private static ImmutableArray<TextEdit> Deduplicate(SourceText sourceText, ImmutableArray<TextEdit> edits)
+    {
+        if (edits.Length <= 1)
+        {
+            return edits;
+        }
+
+        using var _ = HashSetPool<(int Start, int Length, string? NewText)>.GetPooledObject(out var seenEdits);
+        using var builder = new PooledArrayBuilder<TextEdit>(edits.Length);
+
+        foreach (var edit in edits)
+        {
+            var change = sourceText.GetTextChange(edit);
+            if (seenEdits.Add((change.Span.Start, change.Span.Length, change.NewText)))
+            {
+                builder.Add(edit);
+            }
+        }
+
+        return builder.ToImmutableAndClear();
+    }
+
+    private static SumType<TextEdit, AnnotatedTextEdit>[] Deduplicate(SourceText sourceText, SumType<TextEdit, AnnotatedTextEdit>[] edits)
+    {
+        if (edits.Length <= 1)
+        {
+            return edits;
+        }
+
+        using var _ = HashSetPool<(int Start, int Length, string? NewText)>.GetPooledObject(out var seenEdits);
+        using var builder = new PooledArrayBuilder<SumType<TextEdit, AnnotatedTextEdit>>(edits.Length);
+
+        foreach (var edit in edits)
+        {
+            var textEdit = (TextEdit)edit;
+            var change = sourceText.GetTextChange(textEdit);
+            if (seenEdits.Add((change.Span.Start, change.Span.Length, change.NewText)))
+            {
+                builder.Add(edit);
+            }
+        }
+
+        return builder.ToArrayAndClear();
     }
 }

src/Razor/src/Razor/src/Microsoft.CodeAnalysis.Remote.Razor/Rename/RemoteRenameService.cs

@@ -66,7 +66,7 @@ protected override IRemoteRenameService CreateService(in ServiceArgs args)
         var positionInfo = GetPositionInfo(codeDocument, hostDocumentIndex, preferCSharpOverHtml: true);
 
         var generatedDocument = await context.Snapshot
-            .GetGeneratedDocumentAsync(cancellationToken)
+            .GetGeneratedDocumentAsync(positionInfo.InDeclDocument, cancellationToken)
             .ConfigureAwait(false);
 
         var razorEdit = await _renameService
@@ -134,7 +134,7 @@ protected override IRemoteRenameService CreateService(in ServiceArgs args)
             return RemoteResponse<LspRange?>.CallHtml;
         }
 
-        var generatedDocument = await context.Snapshot.GetGeneratedDocumentAsync(cancellationToken).ConfigureAwait(false);
+        var generatedDocument = await context.Snapshot.GetGeneratedDocumentAsync(positionInfo.InDeclDocument, cancellationToken).ConfigureAwait(false);
 
         var csharpRange = await PrepareRenameHandler.GetRenameRangeAsync(generatedDocument, positionInfo.Position.ToLinePosition(), cancellationToken).ConfigureAwait(false);
 
@@ -143,7 +143,7 @@ protected override IRemoteRenameService CreateService(in ServiceArgs args)
             return RemoteResponse<LspRange?>.NoFurtherHandling;
         }
 
-        if (!DocumentMappingService.TryMapToRazorDocumentRange(codeDocument.GetRequiredImplCSharpDocument(), csharpRange, out var mappedRange))
+        if (!DocumentMappingService.TryMapToRazorDocumentRange(codeDocument.GetRequiredCSharpDocument(positionInfo.InDeclDocument), csharpRange, out var mappedRange))
         {
             return RemoteResponse<LspRange?>.NoFurtherHandling;
         }
@@ -228,7 +228,11 @@ protected override IRemoteRenameService CreateService(in ServiceArgs args)
             return null;
         }
 
-        var generatedDocument = await context.Snapshot.GetGeneratedDocumentAsync(cancellationToken).ConfigureAwait(false);
+        // Component file rename updates the generated component class declaration, which lives in the
+        // declaration document under SONIC. Fall back to implementation for legacy documents that do
+        // not have a separate declaration document.
+        var generatedDocument = await context.Snapshot.TryGetGeneratedDocumentAsync(declarationDocument: true, cancellationToken).ConfigureAwait(false)
+            ?? await context.Snapshot.GetGeneratedDocumentAsync(declarationDocument: false, cancellationToken).ConfigureAwait(false);
         var text = await generatedDocument.GetTextAsync(cancellationToken).ConfigureAwait(false);
         var tree = await generatedDocument.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
         var declaration = tree.AssumeNotNull().DescendantNodes().OfType<ClassDeclarationSyntax>().FirstOrDefault();

src/Razor/src/Razor/test/Microsoft.CodeAnalysis.Razor.CohostingShared.UnitTests/Endpoints/CohostPrepareRenameEndpointTest.cs

@@ -11,7 +11,7 @@ namespace Microsoft.VisualStudio.Razor.LanguageClient.Cohost;
 
 public class CohostPrepareRenameEndpointTest(ITestOutputHelper testOutputHelper) : CohostEndpointTestBase(testOutputHelper)
 {
-    [Fact(Skip = "PROTOTYPE(sonic): cohosting feature not yet decl/impl split aware; see PR #83887")]
+    [Fact]
     public Task CSharp_Method()
         => VerifyPrepareRenameAsync(
             input: """

src/Razor/src/Razor/test/Microsoft.CodeAnalysis.Razor.CohostingShared.UnitTests/Endpoints/CohostRenameEndpointTest.cs

@@ -20,7 +20,7 @@ namespace Microsoft.VisualStudio.Razor.LanguageClient.Cohost;
 [Collection(nameof(CohostRenameEndpointTest))]
 public class CohostRenameEndpointTest(ITestOutputHelper testOutputHelper) : CohostEndpointTestBase(testOutputHelper)
 {
-    [Fact(Skip = "PROTOTYPE(sonic): cohosting feature not yet decl/impl split aware; see PR #83887")]
+    [Fact]
     public Task CSharp_SameFile()
         => VerifyRenamesAsync(
             input: """
@@ -41,21 +41,56 @@ The end.
             newName: "CallThisFunction",
             expected: """
                 This is a Razor document.
-                
+
                 <h1>@CallThisFunction()</h1>
-                
+
                 @code
                 {
                     public string CallThisFunction()
                     {
                         return $"Hi from {nameof(CallThisFunction)}";
                     }
                 }
-
+
+                The end.
+                """);
+
+    [Fact]
+    public Task CSharp_SameFile_FromMethodBody()
+        => VerifyRenamesAsync(
+            input: """
+                This is a Razor document.
+
+                <h1>@MyMethod()</h1>
+
+                @code
+                {
+                    public string MyMethod()
+                    {
+                        return MyMe$$thod();
+                    }
+                }
+
+                The end.
+                """,
+            newName: "CallThisFunction",
+            expected: """
+                This is a Razor document.
+
+                <h1>@CallThisFunction()</h1>
+
+                @code
+                {
+                    public string CallThisFunction()
+                    {
+                        return CallThisFunction();
+                    }
+                }
+
                 The end.
                 """);
 
-    [Fact(Skip = "PROTOTYPE(sonic): cohosting feature not yet decl/impl split aware; see PR #83887")]
+    [Fact]
     public Task CSharp_WithOtherFile()
         => VerifyRenamesAsync(
             input: """
@@ -116,7 +151,7 @@ public void CallThisFunction()
                     """)
             ]);
 
-    [Fact(Skip = "PROTOTYPE(sonic): cohosting feature not yet decl/impl split aware; see PR #83887")]
+    [Fact]
     public Task CSharp_Inherits()
        => VerifyRenamesAsync(
            input: """
@@ -187,7 +222,7 @@ public class OtherModel
             ],
             fileKind: RazorFileKind.Legacy);
 
-    [Fact(Skip = "PROTOTYPE(sonic): cohosting feature not yet decl/impl split aware; see PR #83887")]
+    [Fact]
     public Task CSharp_Implements()
         => VerifyRenamesAsync(
             input: """
@@ -220,7 +255,7 @@ public interface IMyFace
                     """)
             ]);
 
-    [Fact(Skip = "PROTOTYPE(sonic): cohosting feature not yet decl/impl split aware; see PR #83887")]
+    [Fact]
     public Task CSharp_TypeParam()
        => VerifyRenamesAsync(
            input: """
@@ -253,7 +288,50 @@ public interface IMyFace
                     """)
            ]);
 
-    [Fact(Skip = "PROTOTYPE(sonic): cohosting feature not yet decl/impl split aware; see PR #83887")]
+    [Fact]
+    public Task CSharp_TypeParameter_FromDirective()
+       => VerifyRenamesAsync(
+           input: """
+               @typeparam TI$$tem
+
+               This is a Razor document.
+
+               <h1>@typeof(TItem).Name</h1>
+
+               @code
+               {
+                   private TItem? _item;
+
+                   public TItem? GetItem()
+                   {
+                       return _item;
+                   }
+               }
+
+               The end.
+               """,
+           newName: "TModel",
+           expected: """
+               @typeparam TModel
+
+               This is a Razor document.
+
+               <h1>@typeof(TModel).Name</h1>
+
+               @code
+               {
+                   private TModel? _item;
+
+                   public TModel? GetItem()
+                   {
+                       return _item;
+                   }
+               }
+
+               The end.
+               """);
+
+    [Fact]
     public Task CSharp_Attribute()
        => VerifyRenamesAsync(
            input: """
@@ -286,7 +364,7 @@ public class HasJacketAttribute : Attribute
                     """)
            ]);
 
-    [Fact(Skip = "PROTOTYPE(sonic): cohosting feature not yet decl/impl split aware; see PR #83887")]
+    [Fact]
     public Task CSharp_Attribute_FullName()
        => VerifyRenamesAsync(
            input: """
@@ -385,7 +463,7 @@ The end.
             additionalExpectedFiles:
                 [(FileUri("DifferentName.razor"), "")]);
 
-    [Theory(Skip = "PROTOTYPE(sonic): cohosting feature not yet decl/impl split aware; see PR #83887")]
+    [Theory]
     [InlineData("My.$$Foo.Component")]
     [InlineData("My.F$$oo.Component")]
     [InlineData("My.Foo$$.Component")]
@@ -448,7 +526,7 @@ The end.
                     @namespace My.DifferentName
                     """)]);
 
-    [Fact(Skip = "PROTOTYPE(sonic): cohosting feature not yet decl/impl split aware; see PR #83887")]
+    [Fact]
     public Task Component_CSharp_FullyQualified_Namespace()
         => VerifyRenamesAsync(
             input: $"""
@@ -624,7 +702,7 @@ The end.
             additionalExpectedFiles:
                 [(FileUri("DifferentName.razor"), "")]);
 
-    [Fact(Skip = "PROTOTYPE(sonic): cohosting feature not yet decl/impl split aware; see PR #83887")]
+    [Fact]
     public Task Component_Attribute()
         => VerifyRenamesAsync(
             input: $"""
@@ -687,7 +765,47 @@ The end.
                     """)
             ]);
 
-    [Fact(Skip = "PROTOTYPE(sonic): cohosting feature not yet decl/impl split aware; see PR #83887")]
+    [Fact]
+    public Task Component_Attribute_FromParameterDeclaration()
+        => VerifyRenamesAsync(
+            input: """
+                This is a Razor document.
+
+                <p>@Title</p>
+
+                @code {
+                    [Parameter]
+                    public string Tit$$le { get; set; } = nameof(Title);
+                }
+                """,
+            additionalFiles: [
+                (FilePath("OtherComponent.razor"), """
+                    <Component Title="Hello1" />
+                    <Component Title="Hello2">
+                    </Component>
+                    """)
+            ],
+            newName: "Name",
+            expected: """
+                This is a Razor document.
+
+                <p>@Name</p>
+
+                @code {
+                    [Parameter]
+                    public string Name { get; set; } = nameof(Name);
+                }
+                """,
+            additionalExpectedFiles: [
+                (FileUri("OtherComponent.razor"), """
+                    <Component Name="Hello1" />
+                    <Component Name="Hello2">
+                    </Component>
+                    """)
+            ],
+            documentFilePath: FilePath("Component.razor"));
+
+    [Fact]
     public Task Component_BindAttribute()
         => VerifyRenamesAsync(
             input: $"""
@@ -1215,7 +1333,7 @@ public class DifferentName : ComponentBase
                     """)
             ]);
 
-    [Fact(Skip = "PROTOTYPE(sonic): cohosting feature not yet decl/impl split aware; see PR #83887")]
+    [Fact]
     public Task Component_Namespace_WithNonRazorCSharpFile()
         => VerifyRenamesAsync(
             input: $"""
@@ -1462,11 +1580,12 @@ private async Task VerifyRenamesAsync(
         string expected,
         RazorFileKind? fileKind = null,
         DocumentUri? newFileUri = null,
+        string? documentFilePath = null,
         (string fileName, string contents)[]? additionalFiles = null,
         (DocumentUri fileUri, string contents)[]? additionalExpectedFiles = null)
     {
         TestFileMarkupParser.GetPosition(input, out var source, out var cursorPosition);
-        var document = CreateProjectAndRazorDocument(source, fileKind, additionalFiles: additionalFiles);
+        var document = CreateProjectAndRazorDocument(source, fileKind, documentFilePath: documentFilePath, additionalFiles: additionalFiles);
         var inputText = await document.GetTextAsync(DisposalToken);
         var position = inputText.GetPosition(cursorPosition);