From 28745474ba00975c11c86d98e80d35cc69c03ac1 Mon Sep 17 00:00:00 2001
From: Julien Couvreur <jcouv@users.noreply.github.com>
Date: Thu, 7 Apr 2022 14:52:58 -0700
Subject: [PATCH] Instrument ReferenceCachingCS for flakiness (#60585)

---
 src/Compilers/Server/VBCSCompilerTests/CompilerServerTests.cs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/Compilers/Server/VBCSCompilerTests/CompilerServerTests.cs b/src/Compilers/Server/VBCSCompilerTests/CompilerServerTests.cs
index e97a6bf923f86..ae25a254659c0 100644
--- a/src/Compilers/Server/VBCSCompilerTests/CompilerServerTests.cs
+++ b/src/Compilers/Server/VBCSCompilerTests/CompilerServerTests.cs
@@ -19,6 +19,7 @@
 using Microsoft.CodeAnalysis.CommandLine;
 using Microsoft.CodeAnalysis.Test.Utilities;
 using Roslyn.Test.Utilities;
+using Roslyn.Utilities;
 using Xunit;
 using Xunit.Abstractions;
 
@@ -949,7 +950,8 @@ public static void Main()
     { Console.WriteLine(""Hello3 from {0}"", Library.GetString2()); }
 }"}};
                             result = RunCommandLineCompiler(CSharpCompilerClientExecutable, $"hello3.cs /shared:{serverData.PipeName} /nologo /r:lib.dll /out:hello3.exe", rootDirectory, files);
-                            Assert.Equal("", result.Output);
+                            // Instrumenting to assist investigation of flakiness. Tracked by https://github.com/dotnet/roslyn/issues/19763
+                            RoslynDebug.AssertOrFailFast("" == result.Output);
                             Assert.Equal(0, result.ExitCode);
 
                             // Run hello3.exe. Should work.