1 files changed, 15 insertions, 9 deletions
diff --git a/src/libraries/System.Runtime.InteropServices/gen/Microsoft.Interop.SourceGeneration/IncrementalGeneratorInitializationContextExtensions.cs b/src/libraries/System.Runtime.InteropServices/gen/Microsoft.Interop.SourceGeneration/IncrementalGeneratorInitializationContextExtensions.cs
index 0b008795884..20a1818a33e 100644
--- a/src/libraries/System.Runtime.InteropServices/gen/Microsoft.Interop.SourceGeneration/IncrementalGeneratorInitializationContextExtensions.cs
+++ b/src/libraries/System.Runtime.InteropServices/gen/Microsoft.Interop.SourceGeneration/IncrementalGeneratorInitializationContextExtensions.cs
@@ -3,6 +3,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Collections.Immutable;
 using System.Linq;
 using System.Text;
 using Microsoft.CodeAnalysis;
@@ -27,12 +28,21 @@ namespace Microsoft.Interop
         public static void RegisterConcatenatedSyntaxOutputs<TNode>(this IncrementalGeneratorInitializationContext context, IncrementalValuesProvider<TNode> nodes, string fileName)
             where TNode : SyntaxNode
         {
-            IncrementalValueProvider<string> generatedMethods = nodes
+            IncrementalValueProvider<ImmutableArray<string>> generatedMethods = nodes
                 .Select(
                     static (node, ct) => node.NormalizeWhitespace().ToFullString())
-                .Collect()
-                .Select(static (generatedSources, ct) =>
+                .Collect();
+
+            context.RegisterSourceOutput(generatedMethods,
+                (context, generatedSources) =>
                 {
+                    // Don't generate a file if we don't have to, to avoid the extra IDE overhead once we have generated
+                    // files in play.
+                    if (generatedSources.IsEmpty)
+                    {
+                        return;
+                    }
+
                     StringBuilder source = new();
                     // Mark in source that the file is auto-generated.
                     source.AppendLine("// <auto-generated/>");
@@ -40,13 +50,9 @@ namespace Microsoft.Interop
                     {
                         source.AppendLine(generated);
                     }
-                    return source.ToString();
-                });
 
-            context.RegisterSourceOutput(generatedMethods,
-                (context, source) =>
-                {
-                    context.AddSource(fileName, source);
+                    // Once https://github.com/dotnet/roslyn/issues/61326 is resolved, we can avoid the ToString() here.
+                    context.AddSource(fileName, source.ToString());
                 });
         }
     }