Adjust upgrade project fixer to support new error code

src/EditorFeatures/CSharpTest/Diagnostics/UpgradeProject/UpgradeProjectTests.cs

@@ -53,7 +53,7 @@ public async Task UpgradeProjectFromCSharp7_2ToCSharp8()
 {
     object F = [|null!|];
 }",
-                LanguageVersion.CSharp8,
+                LanguageVersion.Preview,
                 new CSharpParseOptions(LanguageVersion.CSharp7_2));
         }
 
@@ -65,7 +65,7 @@ public async Task UpgradeProjectFromCSharp7ToCSharp8()
 {
     object F = [|null!|];
 }",
-                LanguageVersion.CSharp8,
+                LanguageVersion.Preview,
                 new CSharpParseOptions(LanguageVersion.CSharp7));
         }
 
@@ -384,7 +384,7 @@ class C
     <Project Language=""Visual Basic"">
     </Project>
 </Workspace>",
-                LanguageVersion.CSharp8,
+                LanguageVersion.Preview,
                 parseOptions: null,
                 index: 1);
         }
@@ -450,6 +450,7 @@ void A()
         [Fact]
         public async Task ListAllSuggestions_CSharp8()
         {
+            var version8 = LanguageVersion.CSharp8.ToDisplayString();
             await TestExactActionSetOfferedAsync(
 
 @"<Workspace>
@@ -470,10 +471,9 @@ void A()
     </Project>
 </Workspace>",
                 new[] {
-                    string.Format(CSharpFeaturesResources.Upgrade_this_project_to_csharp_language_version_0, "8.0 *beta*"),
-                    string.Format(CSharpFeaturesResources.Upgrade_all_csharp_projects_to_language_version_0, "8.0 *beta*")
+                    string.Format(CSharpFeaturesResources.Upgrade_this_project_to_csharp_language_version_0, version8),
+                    string.Format(CSharpFeaturesResources.Upgrade_all_csharp_projects_to_language_version_0, version8)
     });
-            // https://github.com/dotnet/roslyn/issues/29819 Remove beta label once C# 8.0 is RTM
         }
 
         [Fact]
@@ -531,18 +531,19 @@ void A()
         [Fact]
         public async Task OnlyOfferFixAllProjectsFromCSharp6ToDefaultWhenApplicable()
         {
+            var defaultVersion = LanguageVersion.Default.MapSpecifiedToEffectiveVersion().ToDisplayString();
             await TestExactActionSetOfferedAsync(
 
-@"<Workspace>
+$@"<Workspace>
     <Project Language=""C#"" LanguageVersion=""6"">
         <Document>
 class C
-{
+{{
     void A()
-    {
-        var x = [|(1, 2)|];
-    }
-}
+    {{
+#error version:[|{defaultVersion}|]
+    }}
+}}
         </Document>
     </Project>
     <Project Language=""C#"" LanguageVersion=""Default"">
@@ -551,13 +552,15 @@ void A()
     </Project>
 </Workspace>",
                 new[] {
-                    string.Format(CSharpFeaturesResources.Upgrade_this_project_to_csharp_language_version_0, "7.0"),
+                    string.Format(CSharpFeaturesResources.Upgrade_this_project_to_csharp_language_version_0, defaultVersion),
+                    string.Format(CSharpFeaturesResources.Upgrade_all_csharp_projects_to_language_version_0, defaultVersion)
                     });
         }
 
         [Fact]
         public async Task OnlyOfferFixAllProjectsToCSharp8WhenApplicable()
         {
+            var previewVersion = LanguageVersion.Preview.ToDisplayString();
             await TestExactActionSetOfferedAsync(
 
 @"<Workspace>
@@ -575,7 +578,8 @@ class C
     </Project>
 </Workspace>",
                 new[] {
-                    string.Format(CSharpFeaturesResources.Upgrade_this_project_to_csharp_language_version_0, "8.0 *beta*"),
+                    string.Format(CSharpFeaturesResources.Upgrade_this_project_to_csharp_language_version_0, previewVersion),
+                    string.Format(CSharpFeaturesResources.Upgrade_all_csharp_projects_to_language_version_0, previewVersion)
                     });
         }
 
@@ -603,8 +607,8 @@ void A()
     </Project>
 </Workspace>",
                 new[] {
-                    string.Format(CSharpFeaturesResources.Upgrade_this_project_to_csharp_language_version_0, "8.0 *beta*"),
-                    string.Format(CSharpFeaturesResources.Upgrade_all_csharp_projects_to_language_version_0, "8.0 *beta*")
+                    string.Format(CSharpFeaturesResources.Upgrade_this_project_to_csharp_language_version_0, defaultEffectiveVersion),
+                    string.Format(CSharpFeaturesResources.Upgrade_all_csharp_projects_to_language_version_0, defaultEffectiveVersion)
                     });
         }
 

src/Features/CSharp/Portable/UpgradeProject/CSharpUpgradeProjectCodeFixProvider.cs

@@ -31,6 +31,7 @@ internal class CSharpUpgradeProjectCodeFixProvider : AbstractUpgradeProjectCodeF
                 "CS8371", // warning CS8371: Field-targeted attributes on auto-properties are not supported in language version 7.2. Please use language version 7.3 or greater.
                 "CS8400", // error CS8400: Feature is not available in C# 8.0. Please use language version X or greater.
                 "CS8401", // error CS8401: To use '@$' instead of '$@" for a verbatim interpolated string, please use language version 8.0 or greater.
+                "CS8652", // error CS8652: The feature '' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
             });
 
         public override string UpgradeThisProjectResource => CSharpFeaturesResources.Upgrade_this_project_to_csharp_language_version_0;
@@ -41,16 +42,6 @@ public override string SuggestedVersion(ImmutableArray<Diagnostic> diagnostics)
             return RequiredVersion(diagnostics).ToDisplayString();
         }
 
-        public override string AddBetaIfNeeded(string version)
-        {
-            if (version == "8.0")
-            {
-                // https://github.com/dotnet/roslyn/issues/29819 Remove once C# 8.0 is RTM
-                return "8.0 *beta*";
-            }
-            return version;
-        }
-
         private static LanguageVersion RequiredVersion(ImmutableArray<Diagnostic> diagnostics)
         {
             LanguageVersion max = 0;
@@ -61,6 +52,11 @@ private static LanguageVersion RequiredVersion(ImmutableArray<Diagnostic> diagno
                 {
                     max = max > required ? max : required;
                 }
+                else if (diagnostic.Id == "CS8652")
+                {
+                    max = LanguageVersion.Preview;
+                    break;
+                }
             }
 
             return max;

src/Features/Core/Portable/UpgradeProject/AbstractUpgradeProjectCodeFixProvider.cs

@@ -19,7 +19,6 @@ internal abstract partial class AbstractUpgradeProjectCodeFixProvider : CodeFixP
         public abstract bool IsUpgrade(ParseOptions projectOptions, string newVersion);
         public abstract string UpgradeThisProjectResource { get; }
         public abstract string UpgradeAllProjectsResource { get; }
-        public abstract string AddBetaIfNeeded(string version);
 
         public override FixAllProvider GetFixAllProvider()
         {
@@ -43,14 +42,14 @@ protected ImmutableArray<CodeAction> GetUpgradeProjectCodeActionsAsync(CodeFixCo
             var result = new List<CodeAction>();
             var language = project.Language;
 
-            var fixOneProjectTitle = string.Format(UpgradeThisProjectResource, AddBetaIfNeeded(newVersion));
+            var fixOneProjectTitle = string.Format(UpgradeThisProjectResource, newVersion);
             var fixOneProject = new ParseOptionsChangeAction(fixOneProjectTitle,
                 _ => Task.FromResult(UpgradeProject(project, newVersion)));
 
             result.Add(fixOneProject);
             if (solution.Projects.Count(p => CanUpgrade(p, language, newVersion)) > 1)
             {
-                var fixAllProjectsTitle = string.Format(UpgradeAllProjectsResource, AddBetaIfNeeded(newVersion));
+                var fixAllProjectsTitle = string.Format(UpgradeAllProjectsResource, newVersion);
 
                 var fixAllProjects = new ParseOptionsChangeAction(fixAllProjectsTitle,
                     ct => Task.FromResult(UpgradeAllProjects(solution, language, newVersion, ct)));