Use MEF hostservices to create workspace to avoid race condition.

Author: Zubin Ramlakhan

CodeConverter/Shared/SolutionFileTextEditor.cs

@@ -89,7 +89,8 @@ private static (string Find, string Replace, bool FirstOnly) GetProjectGuidRepla
             var projGuidMatch = projGuidRegex.Match(contents);
 
             if (!projGuidMatch.Success) {
-                throw new OperationCanceledException($"{nameof(guidPattern)} {guidPattern} doesn't match with sourceSlnFileContents {contents}");
+                throw new OperationCanceledException($"{nameof(guidPattern)} {guidPattern} doesn't match with" +
+                                                     $" sourceSlnFileContents {contents}");
             }
 
             var oldGuid = projGuidMatch.Groups[1].Value;

CodeConverter/Shared/ThreadSafeWorkspaceHelper.cs

@@ -18,11 +18,21 @@ namespace ICSharpCode.CodeConverter.Shared
     public static class ThreadSafeWorkspaceHelper
     {
         /// <summary>
-        /// Empty solution in an adhoc workspace
+        /// Create an empty adhoc workspace
         /// </summary>
-        public static AsyncLazy<Solution> EmptyAdhocSolution { get; } = new AsyncLazy<Solution>(async () => {
+        public static AsyncLazy<AdhocWorkspace> CreateAdhocWorkspace { get; } = new(async () =>
+        {
             var hostServices = await CreateHostServicesAsync(MefHostServices.DefaultAssemblies);
-            return new AdhocWorkspace(hostServices).CurrentSolution;
+            return new AdhocWorkspace(hostServices);
+        }, JoinableTaskFactorySingleton.Instance);
+
+        /// <summary>
+        /// Empty solution in an adhoc workspace
+        /// </summary>
+        public static AsyncLazy<Solution> EmptyAdhocSolution { get; } = new(async () =>
+        {
+            var adhocWorkspace = await CreateAdhocWorkspace.GetValueAsync();
+            return adhocWorkspace.CurrentSolution;
         }, JoinableTaskFactorySingleton.Instance);
 
         /// <summary>

Tests/LanguageAgnostic/SolutionFileTextEditorTests.cs

@@ -516,7 +516,8 @@ private static string GetProjectProjectReference(IReadOnlyCollection<string> rel
 
         private static Solution CreateTestSolution()
         {
-            var ws = new AdhocWorkspace();
+            var ws = Task.Run(() => ThreadSafeWorkspaceHelper.CreateAdhocWorkspace.GetValueAsync())
+               .GetAwaiter().GetResult();
             var solutionId = SolutionId.CreateNewId(SlnName);
             var versionStamp = VersionStamp.Create();
             var solutionInfo = SolutionInfo.Create(solutionId, versionStamp, SlnFilePath);