Don't add a newline after a component attribute (#9987)

Fixes https://github.com/dotnet/razor/issues/9969
Fixes https://devdiv.visualstudio.com/DevDiv/_workitems/edit/1978110

src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/Formatting/CSharpFormattingPassBase.cs

@@ -554,6 +554,7 @@ internal abstract class CSharpFormattingPassBase : FormattingPassBase
             // Open brace is a child of the C# code block that is the directive itself
             if (owner is RazorMetaCodeSyntax &&
                 owner.Parent is CSharpCodeBlockSyntax codeBlock &&
+                codeBlock.Children.Count > 3 &&
                 owner == codeBlock.Children[3] &&
                 // CSharpCodeBlock -> RazorDirectiveBody -> RazorDirective
                 codeBlock.Parent?.Parent is RazorDirectiveSyntax directive2 &&

src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/Formatting/CSharpOnTypeFormattingPass.cs

@@ -130,10 +130,14 @@ internal class CSharpOnTypeFormattingPass : CSharpFormattingPassBase
 
         // Find the lines that were affected by these edits.
         var originalText = codeDocument.GetSourceText();
+        _logger.LogTestOnly("Original text:\r\n{originalText}", originalText);
+
         var changes = filteredEdits.Select(e => e.ToTextChange(originalText));
 
         // Apply the format on type edits sent over by the client.
         var formattedText = ApplyChangesAndTrackChange(originalText, changes, out _, out var spanAfterFormatting);
+        _logger.LogTestOnly("After C# changes:\r\n{formattedText}", formattedText);
+
         var changedContext = await context.WithTextAsync(formattedText).ConfigureAwait(false);
         var rangeAfterFormatting = spanAfterFormatting.ToRange(formattedText);
 
@@ -142,6 +146,8 @@ internal class CSharpOnTypeFormattingPass : CSharpFormattingPassBase
         // We make an optimistic attempt at fixing corner cases.
         var cleanupChanges = CleanupDocument(changedContext, rangeAfterFormatting);
         var cleanedText = formattedText.WithChanges(cleanupChanges);
+        _logger.LogTestOnly("After CleanupDocument:\r\n{cleanedText}", cleanedText);
+
         changedContext = await changedContext.WithTextAsync(cleanedText).ConfigureAwait(false);
 
         cancellationToken.ThrowIfCancellationRequested();
@@ -209,6 +215,8 @@ internal class CSharpOnTypeFormattingPass : CSharpFormattingPassBase
         {
             // Apply the edits that modify indentation.
             cleanedText = cleanedText.WithChanges(indentationChanges);
+
+            _logger.LogTestOnly("After AdjustIndentationAsync:\r\n{cleanedText}", cleanedText);
         }
 
         // Now that we have made all the necessary changes to the document. Let's diff the original vs final version and return the diff.
@@ -511,6 +519,16 @@ internal class CSharpOnTypeFormattingPass : CSharpFormattingPassBase
             return;
         }
 
+        if (owner is MarkupTagHelperAttributeSyntax { TagHelperAttributeInfo.Bound: true } or
+            MarkupTagHelperDirectiveAttributeSyntax { TagHelperAttributeInfo.Bound: true } or
+            MarkupMinimizedTagHelperAttributeSyntax { TagHelperAttributeInfo.Bound: true } or
+            MarkupMinimizedTagHelperDirectiveAttributeSyntax { TagHelperAttributeInfo.Bound: true })
+        {
+            // Special case, we don't want to add a line break at the end of a component attribute. They are technically
+            // C#, for features like GTD and FAR, but we consider them Html for formatting
+            return;
+        }
+
         var contentStartOffset = text.Lines[mappingEndLineIndex].GetFirstNonWhitespaceOffset(sourceMappingRange.End.Character);
         if (contentStartOffset is null)
         {

src/Razor/test/Microsoft.AspNetCore.Razor.LanguageServer.Test/Formatting_NetFx/CodeDirectiveOnTypeFormattingTest.cs

@@ -12,6 +12,59 @@ namespace Microsoft.AspNetCore.Razor.LanguageServer.Formatting;
 
 public class CodeDirectiveOnTypeFormattingTest(ITestOutputHelper testOutput) : FormattingTestBase(testOutput)
 {
+    [Fact]
+    public async Task FormatsIfStatementInComponent()
+    {
+        await RunOnTypeFormattingTestAsync(
+            input: """
+                    @using Microsoft.AspNetCore.Components.Forms
+
+                    @if (true)
+                    {
+                        <InputSelect TValue="string" DisplayName="asdf">
+                            <option>asdf</option>
+                        </InputSelect>
+                    }$$
+                    """,
+            expected: """
+                    @using Microsoft.AspNetCore.Components.Forms
+                    
+                    @if (true)
+                    {
+                        <InputSelect TValue="string" DisplayName="asdf">
+                            <option>asdf</option>
+                        </InputSelect>
+                    }
+                    """,
+            triggerCharacter: '}');
+    }
+
+    [Fact]
+    public async Task FormatsIfStatementInComponent2()
+    {
+        await RunOnTypeFormattingTestAsync(
+            input: """
+                    @using Microsoft.AspNetCore.Components.Forms
+
+                    @if (true)
+                    {<InputSelect TValue="string" DisplayName="asdf">
+                            <option>asdf</option>
+                        </InputSelect>
+                    }$$
+                    """,
+            expected: """
+                    @using Microsoft.AspNetCore.Components.Forms
+                    
+                    @if (true)
+                    {
+                        <InputSelect TValue="string" DisplayName="asdf">
+                            <option>asdf</option>
+                        </InputSelect>
+                    }
+                    """,
+            triggerCharacter: '}');
+    }
+
     [Fact]
     public async Task CloseCurly_Class_SingleLineAsync()
     {