Fix formatting error when Roslyn adds an extra blank line

src/Razor/src/Razor/src/Microsoft.CodeAnalysis.Razor.Workspaces/Formatting/FormattingUtilities.cs

@@ -369,7 +369,7 @@ public static void GetOriginalDocumentChangesFromLineInfo(FormattingContext cont
                     // the formatter may have inserted a blank line after the current line too. In that case we need to make sure
                     // we advance the formatted line pointer past it, but also include it. This only applies if the line after the
                     // blank line matches the next original line and the next original line isn't blank (ie, an actual insertion)
-                    if (iFormatted + 1 < formattedText.Lines.Count &&
+                    while (iFormatted + 1 < formattedText.Lines.Count &&
                         formattedText.Lines[iFormatted + 1].Span.Length == 0 &&
                         iOriginal + 1 < originalText.Lines.Count &&
                         originalText.Lines[iOriginal + 1] is { } nextOriginalLine &&
@@ -384,6 +384,20 @@ public static void GetOriginalDocumentChangesFromLineInfo(FormattingContext cont
                     }
                 }
             }
+            else if (originalText.Lines[iOriginal] is { } blankOriginalLine &&
+                blankOriginalLine.GetFirstNonWhitespaceOffset() is null)
+            {
+                // The current lines are an aligned blank pair. Consume any additional formatted blank lines
+                // before the next non-blank original line so the line mapping remains synchronized.
+                while (iFormatted + 1 < formattedText.Lines.Count &&
+                    formattedText.Lines[iFormatted + 1].Span.Length == 0 &&
+                    iOriginal + 1 < originalText.Lines.Count &&
+                    originalText.Lines[iOriginal + 1].GetFirstNonWhitespaceOffset() is not null)
+                {
+                    iFormatted++;
+                    formattingChanges.Add(new TextChange(new(blankOriginalLine.EndIncludingLineBreak, 0), context.NewLineString));
+                }
+            }
 
             if (lineInfo.SkipNextLine)
             {

src/Razor/src/Razor/test/Microsoft.CodeAnalysis.Razor.CohostingShared.UnitTests/Formatting/DocumentFormattingTest.cs

@@ -8332,6 +8332,60 @@ public interface Bar
                 """);
     }
 
+    [Fact]
+    [WorkItem("https://devdiv.visualstudio.com/DevDiv/_workitems/edit/3041882")]
+    public async Task IncompleteObjectCreation_UseTabs()
+    {
+        TestCode input = """
+            @code {
+                private void Method()
+                {
+                    value = new object()
+
+                    other = true;
+                }
+            }
+            """;
+
+        await RunFormattingTestAsync(
+            input: input,
+            htmlFormatted: input.Text,
+            expected: """
+                @code {
+                	private void Method()
+                	{
+                		value = new object()
+
+
+                		other = true;
+                	}
+                }
+                """,
+            insertSpaces: false);
+    }
+
+    [Fact]
+    [WorkItem("https://devdiv.visualstudio.com/DevDiv/_workitems/edit/3041882")]
+    public async Task IncompleteObjectCreation_UseSpaces()
+    {
+        TestCode input = """
+            @code {
+                private void Method()
+                {
+                    value = new object()
+
+                    other = true;
+                }
+            }
+            """;
+
+        await RunFormattingTestAsync(
+            input: input,
+            htmlFormatted: input.Text,
+            expected: input.Text,
+            insertSpaces: true);
+    }
+
     [Fact]
     public async Task MultipleCodeBlockDirectives()
     {

src/Razor/src/Razor/test/Microsoft.VisualStudio.LanguageServices.Razor.UnitTests/Cohost/Formatting/FormattingLogTest.cs

@@ -79,6 +79,11 @@ public async Task PageForMultiGrid()
     public async Task PageForGrid()
         => Assert.NotNull(await GetFormattingEditsAsync());
 
+    [Fact]
+    [WorkItem("https://devdiv.visualstudio.com/DevDiv/_workitems/edit/3041882")]
+    public async Task BoatsSectionRange092858221()
+        => Assert.NotNull(await GetFormattingEditsAsync());
+
     private async Task<TextEdit[]?> GetFormattingEditsAsync([CallerMemberName] string? testName = null)
     {
         var contents = GetResource(testName.AssumeNotNull(), "InitialDocument.txt").AssumeNotNull();

src/Razor/src/Razor/test/Microsoft.VisualStudio.LanguageServices.Razor.UnitTests/TestFiles/FormattingLog/BoatsSectionRange092858221/FileKind.json

@@ -0,0 +1 @@
+1

src/Razor/src/Razor/test/Microsoft.VisualStudio.LanguageServices.Razor.UnitTests/TestFiles/FormattingLog/BoatsSectionRange092858221/HtmlChanges.json

@@ -0,0 +1 @@
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