Merge pull request #46176 from 333fred/update-references

333fred · web-flow · commit 71e720ec0983 · 2020-07-27T18:34:36.000-07:00
diff --git a/eng/Versions.props b/eng/Versions.props
@@ -252,8 +252,8 @@
     -->
     <NewtonsoftJsonVersion>12.0.2</NewtonsoftJsonVersion>
     <StreamJsonRpcVersion>2.4.34</StreamJsonRpcVersion>
-    <SystemCollectionsImmutableVersion>1.5.0</SystemCollectionsImmutableVersion>
-    <SystemReflectionMetadataVersion>1.6.0</SystemReflectionMetadataVersion>
+    <SystemCollectionsImmutableVersion>5.0.0-preview.8.20371.14</SystemCollectionsImmutableVersion>
+    <SystemReflectionMetadataVersion>5.0.0-preview.8.20371.14</SystemReflectionMetadataVersion>
     <MicrosoftVisualStudioStaticReviewsEmbeddableVersion>0.1.102-alpha</MicrosoftVisualStudioStaticReviewsEmbeddableVersion>
     <MicrosoftBclAsyncInterfacesVersion>1.1.0</MicrosoftBclAsyncInterfacesVersion>
   </PropertyGroup>
diff --git a/src/Analyzers/Core/Analyzers/RemoveUnnecessarySuppressions/AbstractRemoveUnnecessaryPragmaSuppressionsDiagnosticAnalyzer.cs b/src/Analyzers/Core/Analyzers/RemoveUnnecessarySuppressions/AbstractRemoveUnnecessaryPragmaSuppressionsDiagnosticAnalyzer.cs
@@ -60,7 +60,7 @@ private ImmutableHashSet<int> GetSupportedCompilerErrorCodes()
                 var methodInfo = compilerAnalyzerType.GetMethod("GetSupportedErrorCodes", BindingFlags.Instance | BindingFlags.NonPublic)!;
                 var compilerAnalyzerInstance = Activator.CreateInstance(compilerAnalyzerType);
                 var supportedCodes = methodInfo.Invoke(compilerAnalyzerInstance, Array.Empty<object>()) as IEnumerable<int>;
-                return supportedCodes.ToImmutableHashSet();
+                return supportedCodes?.ToImmutableHashSet() ?? ImmutableHashSet<int>.Empty;
             }
             catch (Exception ex)
             {
diff --git a/src/Compilers/CSharp/Portable/Binder/DecisionDagBuilder.cs b/src/Compilers/CSharp/Portable/Binder/DecisionDagBuilder.cs
@@ -1005,7 +1005,7 @@ private static (
                 }
                 IValueSet fromTestPassing = valueFac.Related(relation.Operator(), value);
                 IValueSet fromTestFailing = fromTestPassing.Complement();
-                if (values.TryGetValue(test.Input, out IValueSet tempValuesBeforeTest))
+                if (values.TryGetValue(test.Input, out IValueSet? tempValuesBeforeTest))
                 {
                     fromTestPassing = fromTestPassing.Intersect(tempValuesBeforeTest);
                     fromTestFailing = fromTestFailing.Intersect(tempValuesBeforeTest);
diff --git a/src/Compilers/CSharp/Portable/Compilation/CSharpCompilation.cs b/src/Compilers/CSharp/Portable/Compilation/CSharpCompilation.cs
@@ -3664,7 +3664,7 @@ void WriteValue(string key, string value)
 
         private ImmutableArray<string> GetPreprocessorSymbols()
         {
-            CSharpSyntaxTree firstTree = (CSharpSyntaxTree)SyntaxTrees.FirstOrDefault();
+            CSharpSyntaxTree? firstTree = (CSharpSyntaxTree?)SyntaxTrees.FirstOrDefault();
 
             if (firstTree is null)
             {
diff --git a/src/Compilers/CSharp/Portable/Compilation/MemberSemanticModel.cs b/src/Compilers/CSharp/Portable/Compilation/MemberSemanticModel.cs
@@ -704,7 +704,7 @@ private T GetRemappedSymbol<T>(T originalSymbol) where T : Symbol
             EnsureNullabilityAnalysisPerformedIfNecessary();
             if (_lazyRemappedSymbols is null) return originalSymbol;
 
-            if (_lazyRemappedSymbols.TryGetValue(originalSymbol, out Symbol remappedSymbol))
+            if (_lazyRemappedSymbols.TryGetValue(originalSymbol, out Symbol? remappedSymbol))
             {
                 RoslynDebug.Assert(remappedSymbol is object);
                 return (T)remappedSymbol;
diff --git a/src/Compilers/CSharp/Portable/FlowAnalysis/NullableWalker.SnapshotManager.cs b/src/Compilers/CSharp/Portable/FlowAnalysis/NullableWalker.SnapshotManager.cs
@@ -6,6 +6,7 @@
 using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp.Symbols;
 using Microsoft.CodeAnalysis.PooledObjects;
 using Roslyn.Utilities;
@@ -98,7 +99,7 @@ private SnapshotManager(ImmutableArray<SharedWalkerState> walkerSharedStates, Im
                 return null;
             }
 
-            internal bool TryGetUpdatedSymbol(BoundNode node, Symbol symbol, out Symbol updatedSymbol)
+            internal bool TryGetUpdatedSymbol(BoundNode node, Symbol symbol, [NotNullWhen(true)] out Symbol? updatedSymbol)
             {
                 return _updatedSymbolsMap.TryGetValue((node, symbol), out updatedSymbol);
             }
diff --git a/src/Compilers/CSharp/Portable/Symbols/Source/SourceMemberContainerSymbol.cs b/src/Compilers/CSharp/Portable/Symbols/Source/SourceMemberContainerSymbol.cs
@@ -1520,7 +1520,7 @@ private void CheckMemberNameConflicts(DiagnosticBag diagnostics)
             foreach (var pair in membersByName)
             {
                 var name = pair.Key;
-                Symbol lastSym = GetTypeMembers(name).FirstOrDefault();
+                Symbol? lastSym = GetTypeMembers(name).FirstOrDefault();
                 methodsBySignature.Clear();
                 // Conversion collisions do not consider the name of the conversion,
                 // so do not clear that dictionary.
@@ -1567,7 +1567,7 @@ private void CheckMemberNameConflicts(DiagnosticBag diagnostics)
                     //   following a field of the same name, or a field and a nested type of the same name.
                     //
 
-                    if ((object)lastSym != null)
+                    if ((object?)lastSym != null)
                     {
                         if (symbol.Kind != SymbolKind.Method || lastSym.Kind != SymbolKind.Method)
                         {
diff --git a/src/Compilers/Core/CodeAnalysisTest/Analyzers/AnalyzerFileReferenceAppDomainTests.cs b/src/Compilers/Core/CodeAnalysisTest/Analyzers/AnalyzerFileReferenceAppDomainTests.cs
@@ -91,6 +91,7 @@ public class TestAnalyzer : DiagnosticAnalyzer
                 new SyntaxTree[] { CSharp.SyntaxFactory.ParseSyntaxTree(analyzerSource) },
                 new MetadataReference[]
                 {
+                    TestMetadata.NetStandard20.mscorlib,
                     TestMetadata.NetStandard20.netstandard,
                     TestMetadata.NetStandard20.SystemRuntime,
                     MetadataReference.CreateFromFile(immutable.Path),
diff --git a/src/Compilers/Core/CodeAnalysisTest/ShadowCopyAnalyzerAssemblyLoaderTests.cs b/src/Compilers/Core/CodeAnalysisTest/ShadowCopyAnalyzerAssemblyLoaderTests.cs
@@ -57,6 +57,7 @@ public abstract class AbstractTestAnalyzer : DiagnosticAnalyzer
                    new SyntaxTree[] { CSharp.SyntaxFactory.ParseSyntaxTree(analyzerDependencySource) },
                    new MetadataReference[]
                    {
+                    TestMetadata.NetStandard20.mscorlib,
                     TestMetadata.NetStandard20.netstandard,
                     TestMetadata.NetStandard20.SystemRuntime,
                     MetadataReference.CreateFromFile(immutable.Path),
@@ -83,6 +84,7 @@ public sealed class TestAnalyzer : AbstractTestAnalyzer
                    new SyntaxTree[] { CSharp.SyntaxFactory.ParseSyntaxTree(analyzerMainSource) },
                    new MetadataReference[]
                    {
+                        TestMetadata.NetStandard20.mscorlib,
                         TestMetadata.NetStandard20.netstandard,
                         TestMetadata.NetStandard20.SystemRuntime,
                         MetadataReference.CreateFromFile(immutable.Path),
diff --git a/src/Compilers/Core/Portable/Collections/StaticCast.cs b/src/Compilers/Core/Portable/Collections/StaticCast.cs
@@ -12,7 +12,10 @@ internal static class StaticCast<T>
     {
         internal static ImmutableArray<T> From<TDerived>(ImmutableArray<TDerived> from) where TDerived : class?, T
         {
+            // Remove the pragma when we get a version with https://github.com/dotnet/runtime/issues/39799 fixed
+#pragma warning disable CS8634
             return ImmutableArray<T>.CastUp(from);
+#pragma warning restore CS8634
         }
     }
 }
diff --git a/src/Compilers/Core/Portable/CommandLine/AnalyzerConfig.cs b/src/Compilers/Core/Portable/CommandLine/AnalyzerConfig.cs
@@ -83,7 +83,7 @@ public sealed partial class AnalyzerConfig
         /// <summary>
         /// Gets whether this editorconfig is a topmost editorconfig.
         /// </summary>
-        internal bool IsRoot => GlobalSection.Properties.TryGetValue("root", out string val) && val == "true";
+        internal bool IsRoot => GlobalSection.Properties.TryGetValue("root", out string? val) && val == "true";
 
         /// <summary>
         /// Gets whether this editorconfig is a global editorconfig.
diff --git a/src/Compilers/Core/Portable/DiagnosticAnalyzer/AnalysisResult.cs b/src/Compilers/Core/Portable/DiagnosticAnalyzer/AnalysisResult.cs
@@ -114,6 +114,7 @@ private static void AddLocalDiagnostics<T>(
             ImmutableDictionary<T, ImmutableDictionary<DiagnosticAnalyzer, ImmutableArray<Diagnostic>>> localDiagnostics,
             ImmutableHashSet<DiagnosticAnalyzer> excludedAnalyzers,
             ImmutableArray<Diagnostic>.Builder builder)
+            where T : notnull
         {
             foreach (var diagnosticsByTree in localDiagnostics)
             {
diff --git a/src/Compilers/Core/Portable/DiagnosticAnalyzer/AnalyzerFileReference.cs b/src/Compilers/Core/Portable/DiagnosticAnalyzer/AnalyzerFileReference.cs
@@ -312,7 +312,7 @@ private sealed class Extensions<TExtension> where TExtension : class
             private readonly AttributePredicate _attributePredicate;
             private readonly AttributeLanguagesFunc _languagesFunc;
             private ImmutableArray<TExtension> _lazyAllExtensions;
-            private ImmutableDictionary<string, ImmutableArray<TExtension>>? _lazyExtensionsPerLanguage;
+            private ImmutableDictionary<string, ImmutableArray<TExtension>> _lazyExtensionsPerLanguage;
             private ImmutableDictionary<string, ImmutableHashSet<string>>? _lazyExtensionTypeNameMap;
 
             internal Extensions(AnalyzerFileReference reference, AttributePredicate attributePredicate, AttributeLanguagesFunc languagesFunc)
@@ -467,7 +467,7 @@ internal void AddExtensions(ImmutableArray<TExtension>.Builder builder, string l
 
             private ImmutableArray<TExtension> GetLanguageSpecificAnalyzers(Assembly analyzerAssembly, ImmutableDictionary<string, ImmutableHashSet<string>> analyzerTypeNameMap, string language, ref bool reportedError)
             {
-                ImmutableHashSet<string> languageSpecificAnalyzerTypeNames;
+                ImmutableHashSet<string>? languageSpecificAnalyzerTypeNames;
                 if (!analyzerTypeNameMap.TryGetValue(language, out languageSpecificAnalyzerTypeNames))
                 {
                     return ImmutableArray<TExtension>.Empty;
diff --git a/src/Compilers/Core/Portable/InternalUtilities/GeneratedCodeUtilities.cs b/src/Compilers/Core/Portable/InternalUtilities/GeneratedCodeUtilities.cs
@@ -151,7 +151,7 @@ private static bool BeginsWithAutoGeneratedComment(
         {
             // Check for explicit user configuration for generated code.
             //     generated_code = true | false
-            if (options.TryGetValue("generated_code", out string optionValue) &&
+            if (options.TryGetValue("generated_code", out string? optionValue) &&
                 bool.TryParse(optionValue, out var boolValue))
             {
                 return boolValue;
diff --git a/src/Compilers/Core/Portable/InternalUtilities/ImmutableArrayExtensions.cs b/src/Compilers/Core/Portable/InternalUtilities/ImmutableArrayExtensions.cs
@@ -49,7 +49,10 @@ internal static int BinarySearch<TElement, TValue>(this ImmutableArray<TElement>
 
         internal static ImmutableArray<TDerived> CastDown<TOriginal, TDerived>(this ImmutableArray<TOriginal> array) where TDerived : class?, TOriginal
         {
+            // Remove the pragma when we get a version with https://github.com/dotnet/runtime/issues/39799 fixed
+#pragma warning disable CS8634
             return array.CastArray<TDerived>();
+#pragma warning restore CS8634
         }
     }
 }
diff --git a/src/EditorFeatures/Core/Implementation/CodeFixes/CodeFixService.cs b/src/EditorFeatures/Core/Implementation/CodeFixes/CodeFixService.cs
@@ -268,7 +268,7 @@ public async Task<Document> ApplyCodeFixesForSpecificDiagnosticIdAsync(Document
             return solution.GetDocument(document.Id) ?? throw new NotSupportedException(EditorFeaturesResources.Removal_of_document_not_supported);
         }
 
-        private bool TryGetWorkspaceFixersMap(Document document, out Lazy<ImmutableDictionary<DiagnosticId, ImmutableArray<CodeFixProvider>>> fixerMap)
+        private bool TryGetWorkspaceFixersMap(Document document, [NotNullWhen(true)] out Lazy<ImmutableDictionary<DiagnosticId, ImmutableArray<CodeFixProvider>>>? fixerMap)
         {
             if (_lazyWorkspaceFixersMap == null)
             {
@@ -279,7 +279,7 @@ private bool TryGetWorkspaceFixersMap(Document document, out Lazy<ImmutableDicti
             return _lazyWorkspaceFixersMap.TryGetValue(document.Project.Language, out fixerMap);
         }
 
-        private bool TryGetWorkspaceFixersPriorityMap(Document document, out Lazy<ImmutableDictionary<CodeFixProvider, int>> fixersPriorityMap)
+        private bool TryGetWorkspaceFixersPriorityMap(Document document, [NotNullWhen(true)] out Lazy<ImmutableDictionary<CodeFixProvider, int>>? fixersPriorityMap)
         {
             if (_lazyFixerPriorityMap == null)
             {
@@ -367,7 +367,7 @@ private async Task AppendFixesAsync(
                     allFixers.AddRange(projectFixers);
                 }
 
-                if (hasAnySharedFixer && fixerMap.Value.TryGetValue(diagnosticId, out var workspaceFixers))
+                if (hasAnySharedFixer && fixerMap!.Value.TryGetValue(diagnosticId, out var workspaceFixers))
                 {
                     if (isInteractive)
                     {
@@ -706,14 +706,14 @@ private async Task<bool> ContainsAnyFixAsync(
 
             if (hasAnyProjectFixer)
             {
-                allFixers = allFixers.AddRange(projectFixers);
+                allFixers = allFixers.AddRange(projectFixers!);
             }
 
             var dx = await diagnostic.ToDiagnosticAsync(document.Project, cancellationToken).ConfigureAwait(false);
 
             if (hasConfigurationFixer)
             {
-                foreach (var lazyConfigurationProvider in lazyConfigurationProviders.Value)
+                foreach (var lazyConfigurationProvider in lazyConfigurationProviders!.Value)
                 {
                     if (lazyConfigurationProvider.IsFixableDiagnostic(dx))
                     {
diff --git a/src/Features/CSharp/Portable/ChangeSignature/CSharpChangeSignatureService.cs b/src/Features/CSharp/Portable/ChangeSignature/CSharpChangeSignatureService.cs
@@ -93,7 +93,7 @@ public CSharpChangeSignatureService()
         {
         }
 
-        public override async Task<(ISymbol symbol, int selectedIndex)> GetInvocationSymbolAsync(
+        public override async Task<(ISymbol? symbol, int selectedIndex)> GetInvocationSymbolAsync(
             Document document, int position, bool restrictToDeclarations, CancellationToken cancellationToken)
         {
             var tree = await document.GetRequiredSyntaxTreeAsync(cancellationToken).ConfigureAwait(false);
diff --git a/src/Features/Core/Portable/ChangeSignature/AbstractChangeSignatureService.cs b/src/Features/Core/Portable/ChangeSignature/AbstractChangeSignatureService.cs
@@ -38,7 +38,7 @@ internal abstract class AbstractChangeSignatureService : ILanguageService
         /// <summary>
         /// Determines the symbol on which we are invoking ReorderParameters
         /// </summary>
-        public abstract Task<(ISymbol symbol, int selectedIndex)> GetInvocationSymbolAsync(Document document, int position, bool restrictToDeclarations, CancellationToken cancellationToken);
+        public abstract Task<(ISymbol? symbol, int selectedIndex)> GetInvocationSymbolAsync(Document document, int position, bool restrictToDeclarations, CancellationToken cancellationToken);
 
         /// <summary>
         /// Given a SyntaxNode for which we want to reorder parameters/arguments, find the 
diff --git a/src/Features/Core/Portable/Diagnostics/EngineV2/DiagnosticIncrementalAnalyzer_IncrementalAnalyzer.cs b/src/Features/Core/Portable/Diagnostics/EngineV2/DiagnosticIncrementalAnalyzer_IncrementalAnalyzer.cs
@@ -449,6 +449,7 @@ private void RaiseProjectDiagnosticsIfNeeded(
 
                     // both old and new has items in them. update existing items
                     RoslynDebug.Assert(oldAnalysisResult.DocumentIds != null);
+                    RoslynDebug.Assert(newAnalysisResult.DocumentIds != null);
 
                     // first remove ones no longer needed.
                     var documentsToRemove = oldAnalysisResult.DocumentIds.Except(newAnalysisResult.DocumentIds);
diff --git a/src/Features/Core/Portable/EditAndContinue/AbstractEditAndContinueAnalyzer.cs b/src/Features/Core/Portable/EditAndContinue/AbstractEditAndContinueAnalyzer.cs
@@ -3004,7 +3004,7 @@ private bool HasMemberInitializerContainingLambda(INamedTypeSymbol type, bool is
             return false;
         }
 
-        private static ISymbol TryGetParameterlessConstructor(INamedTypeSymbol type, bool isStatic)
+        private static ISymbol? TryGetParameterlessConstructor(INamedTypeSymbol type, bool isStatic)
         {
             var oldCtors = isStatic ? type.StaticConstructors : type.InstanceConstructors;
             if (isStatic)
diff --git a/src/Features/Core/Portable/EditAndContinue/DebuggingSession.cs b/src/Features/Core/Portable/EditAndContinue/DebuggingSession.cs
@@ -282,6 +282,7 @@ from region in delta.NonRemappableRegions
         }
 
         private static ImmutableDictionary<K, ImmutableArray<V>> GroupToImmutableDictionary<K, V>(IEnumerable<IGrouping<K, V>> items)
+            where K : notnull
         {
             var builder = ImmutableDictionary.CreateBuilder<K, ImmutableArray<V>>();
 
diff --git a/src/Features/Core/Portable/ExtractMethod/MethodExtractor.Analyzer.cs b/src/Features/Core/Portable/ExtractMethod/MethodExtractor.Analyzer.cs
@@ -92,7 +92,7 @@ public async Task<AnalyzerResult> AnalyzeAsync()
                     Contract.ThrowIfFalse(unused.Count == 0);
                 }
 
-                var thisParameterBeingRead = (IParameterSymbol)dataFlowAnalysisData.ReadInside.FirstOrDefault(s => IsThisParameter(s));
+                var thisParameterBeingRead = (IParameterSymbol?)dataFlowAnalysisData.ReadInside.FirstOrDefault(s => IsThisParameter(s));
                 var isThisParameterWritten = dataFlowAnalysisData.WrittenInside.Any(s => IsThisParameter(s));
 
                 var localFunctionCallsNotWithinSpan = symbolMap.Keys.Where(s => s.IsLocalFunction() && !s.Locations.Any(l => SelectionResult.FinalSpan.Contains(l.SourceSpan)));
diff --git a/src/Features/Core/Portable/QuickInfo/CommonSemanticQuickInfoProvider.ErrorVisitor.cs b/src/Features/Core/Portable/QuickInfo/CommonSemanticQuickInfoProvider.ErrorVisitor.cs
@@ -16,7 +16,7 @@ private class ErrorVisitor : SymbolVisitor<bool>
         {
             private static readonly ErrorVisitor s_instance = new ErrorVisitor();
 
-            public static bool ContainsError(ISymbol symbol)
+            public static bool ContainsError(ISymbol? symbol)
                 => s_instance.Visit(symbol);
 
             public override bool DefaultVisit(ISymbol symbol)
diff --git a/src/Test/Utilities/Portable/Platform/Desktop/TestHelpers.cs b/src/Test/Utilities/Portable/Platform/Desktop/TestHelpers.cs
@@ -83,6 +83,7 @@ public class TestAnalyzer : DiagnosticAnalyzer
                 new SyntaxTree[] { SyntaxFactory.ParseSyntaxTree(analyzerSource) },
                 new MetadataReference[]
                 {
+                    TestMetadata.NetStandard20.mscorlib,
                     TestMetadata.NetStandard20.netstandard,
                     TestMetadata.NetStandard20.SystemRuntime,
                     MetadataReference.CreateFromFile(immutable.Path),
diff --git a/src/VisualStudio/Core/Def/Implementation/Workspace/VisualStudioSymbolNavigationService.cs b/src/VisualStudio/Core/Def/Implementation/Workspace/VisualStudioSymbolNavigationService.cs
@@ -217,7 +217,7 @@ public bool WouldNavigateToSymbol(
         }
 
         public bool WouldNotifyToSpecificSymbol(
-            DefinitionItem definitionItem, string rqName, CancellationToken cancellationToken,
+            DefinitionItem definitionItem, string? rqName, CancellationToken cancellationToken,
             [NotNullWhen(true)] out string? filePath, out int lineNumber, out int charOffset)
         {
             AssertIsForeground();
@@ -262,7 +262,7 @@ public bool WouldNotifyToSpecificSymbol(
 
         private bool TryGetNavigationAPIRequiredArguments(
             DefinitionItem definitionItem,
-            string rqName,
+            string? rqName,
             CancellationToken cancellationToken,
             [NotNullWhen(true)] out IVsHierarchy? hierarchy,
             out uint itemID,
diff --git a/src/VisualStudio/LiveShare/Impl/AbstractGoToDefinitionWithFindUsagesServiceHandler.cs b/src/VisualStudio/LiveShare/Impl/AbstractGoToDefinitionWithFindUsagesServiceHandler.cs
@@ -54,7 +54,7 @@ public async Task<object> HandleAsync(LSP.TextDocumentPositionParams request, Re
             if ((locations.Length == 0) && document.SupportsSemanticModel && this._metadataAsSourceService != null)
             {
                 var symbol = await SymbolFinder.FindSymbolAtPositionAsync(document, position, cancellationToken).ConfigureAwait(false);
-                if (symbol?.Locations.FirstOrDefault().IsInMetadata == true)
+                if (symbol?.Locations.FirstOrDefault()?.IsInMetadata == true)
                 {
                     var declarationFile = await this._metadataAsSourceService.GetGeneratedFileAsync(document.Project, symbol, false, cancellationToken).ConfigureAwait(false);
 
diff --git a/src/Workspaces/CSharp/Portable/Rename/CSharpRenameRewriterLanguageService.cs b/src/Workspaces/CSharp/Portable/Rename/CSharpRenameRewriterLanguageService.cs
@@ -62,7 +62,7 @@ private class RenameRewriter : CSharpSyntaxRewriter
 
             private readonly ISymbol _renamedSymbol;
             private readonly IAliasSymbol? _aliasSymbol;
-            private readonly Location _renamableDeclarationLocation;
+            private readonly Location? _renamableDeclarationLocation;
 
             private readonly RenamedSpansTracker _renameSpansTracker;
             private readonly bool _isVerbatim;
diff --git a/src/Workspaces/Core/Portable/CodeActions/CodeActionWithOptions.cs b/src/Workspaces/Core/Portable/CodeActions/CodeActionWithOptions.cs
@@ -52,7 +52,7 @@ internal override async Task<ImmutableArray<CodeActionOperation>> GetOperationsC
             IProgressTracker progressTracker, CancellationToken cancellationToken)
         {
             var options = this.GetOptions(cancellationToken);
-            return (await this.GetOperationsAsync(options, cancellationToken).ConfigureAwait(false)).ToImmutableArray();
+            return (await this.GetOperationsAsync(options, cancellationToken).ConfigureAwait(false)).ToImmutableArrayOrEmpty();
         }
 
         /// <summary>
diff --git a/src/Workspaces/Core/Portable/Diagnostics/DiagnosticAnalysisResultMap.cs b/src/Workspaces/Core/Portable/Diagnostics/DiagnosticAnalysisResultMap.cs
@@ -17,12 +17,14 @@ internal static class DiagnosticAnalysisResultMap
         public static DiagnosticAnalysisResultMap<TKey, TValue> Create<TKey, TValue>(
             ImmutableDictionary<TKey, TValue> analysisResult,
             ImmutableDictionary<TKey, AnalyzerTelemetryInfo> telemetryInfo)
+            where TKey : notnull
         {
             return new DiagnosticAnalysisResultMap<TKey, TValue>(analysisResult, telemetryInfo);
         }
     }
 
     internal struct DiagnosticAnalysisResultMap<TKey, TValue>
+        where TKey : notnull
     {
         public static readonly DiagnosticAnalysisResultMap<TKey, TValue> Empty = new DiagnosticAnalysisResultMap<TKey, TValue>(
             ImmutableDictionary<TKey, TValue>.Empty,
diff --git a/src/Workspaces/Core/Portable/Rename/IRemoteRenamer.cs b/src/Workspaces/Core/Portable/Rename/IRemoteRenamer.cs
diff --git a/src/Workspaces/Core/Portable/Workspace/Solution/ProjectState.cs b/src/Workspaces/Core/Portable/Workspace/Solution/ProjectState.cs
diff --git a/src/Workspaces/SharedUtilitiesAndExtensions/Compiler/Core/Utilities/CompilerUtilities/ImmutableDictionaryExtensions.cs b/src/Workspaces/SharedUtilitiesAndExtensions/Compiler/Core/Utilities/CompilerUtilities/ImmutableDictionaryExtensions.cs

Original file line number	Diff line number	Diff line change
`@@ -60,7 +60,7 @@ private ImmutableHashSet<int> GetSupportedCompilerErrorCodes()`
`60`	`60`	`var methodInfo = compilerAnalyzerType.GetMethod("GetSupportedErrorCodes", BindingFlags.Instance \| BindingFlags.NonPublic)!;`
`61`	`61`	`var compilerAnalyzerInstance = Activator.CreateInstance(compilerAnalyzerType);`
`62`	`62`	`var supportedCodes = methodInfo.Invoke(compilerAnalyzerInstance, Array.Empty<object>()) as IEnumerable<int>;`
`63`		`- return supportedCodes.ToImmutableHashSet();`
	`63`	`+ return supportedCodes?.ToImmutableHashSet() ?? ImmutableHashSet<int>.Empty;`
`64`	`64`	`}`
`65`	`65`	`catch (Exception ex)`
`66`	`66`	`{`
Original file line number	Diff line number	Diff line change
`@@ -1005,7 +1005,7 @@ private static (`
`1005`	`1005`	`}`
`1006`	`1006`	`IValueSet fromTestPassing = valueFac.Related(relation.Operator(), value);`
`1007`	`1007`	`IValueSet fromTestFailing = fromTestPassing.Complement();`
`1008`		`- if (values.TryGetValue(test.Input, out IValueSet tempValuesBeforeTest))`
	`1008`	`+ if (values.TryGetValue(test.Input, out IValueSet? tempValuesBeforeTest))`
`1009`	`1009`	`{`
`1010`	`1010`	`fromTestPassing = fromTestPassing.Intersect(tempValuesBeforeTest);`
`1011`	`1011`	`fromTestFailing = fromTestFailing.Intersect(tempValuesBeforeTest);`
Original file line number	Diff line number	Diff line change
`@@ -3664,7 +3664,7 @@ void WriteValue(string key, string value)`
`3664`	`3664`
`3665`	`3665`	`private ImmutableArray<string> GetPreprocessorSymbols()`
`3666`	`3666`	`{`
`3667`		`- CSharpSyntaxTree firstTree = (CSharpSyntaxTree)SyntaxTrees.FirstOrDefault();`
	`3667`	`+ CSharpSyntaxTree? firstTree = (CSharpSyntaxTree?)SyntaxTrees.FirstOrDefault();`
`3668`	`3668`
`3669`	`3669`	`if (firstTree is null)`
`3670`	`3670`	`{`
Original file line number	Diff line number	Diff line change
`@@ -704,7 +704,7 @@ private T GetRemappedSymbol<T>(T originalSymbol) where T : Symbol`
`704`	`704`	`EnsureNullabilityAnalysisPerformedIfNecessary();`
`705`	`705`	`if (_lazyRemappedSymbols is null) return originalSymbol;`
`706`	`706`
`707`		`- if (_lazyRemappedSymbols.TryGetValue(originalSymbol, out Symbol remappedSymbol))`
	`707`	`+ if (_lazyRemappedSymbols.TryGetValue(originalSymbol, out Symbol? remappedSymbol))`
`708`	`708`	`{`
`709`	`709`	`RoslynDebug.Assert(remappedSymbol is object);`
`710`	`710`	`return (T)remappedSymbol;`
Original file line number	Diff line number	Diff line change
`@@ -6,6 +6,7 @@`
`6`	`6`	`using System.Collections.Generic;`
`7`	`7`	`using System.Collections.Immutable;`
`8`	`8`	`using System.Diagnostics;`
	`9`	`+using System.Diagnostics.CodeAnalysis;`
`9`	`10`	`using Microsoft.CodeAnalysis.CSharp.Symbols;`
`10`	`11`	`using Microsoft.CodeAnalysis.PooledObjects;`
`11`	`12`	`using Roslyn.Utilities;`
`@@ -98,7 +99,7 @@ private SnapshotManager(ImmutableArray<SharedWalkerState> walkerSharedStates, Im`
`98`	`99`	`return null;`
`99`	`100`	`}`
`100`	`101`
`101`		`- internal bool TryGetUpdatedSymbol(BoundNode node, Symbol symbol, out Symbol updatedSymbol)`
	`102`	`+ internal bool TryGetUpdatedSymbol(BoundNode node, Symbol symbol, [NotNullWhen(true)] out Symbol? updatedSymbol)`
`102`	`103`	`{`
`103`	`104`	`return _updatedSymbolsMap.TryGetValue((node, symbol), out updatedSymbol);`
`104`	`105`	`}`
Original file line number	Diff line number	Diff line change
`@@ -1520,7 +1520,7 @@ private void CheckMemberNameConflicts(DiagnosticBag diagnostics)`
`1520`	`1520`	`foreach (var pair in membersByName)`
`1521`	`1521`	`{`
`1522`	`1522`	`var name = pair.Key;`
`1523`		`- Symbol lastSym = GetTypeMembers(name).FirstOrDefault();`
	`1523`	`+ Symbol? lastSym = GetTypeMembers(name).FirstOrDefault();`
`1524`	`1524`	`methodsBySignature.Clear();`
`1525`	`1525`	`// Conversion collisions do not consider the name of the conversion,`
`1526`	`1526`	`// so do not clear that dictionary.`
`@@ -1567,7 +1567,7 @@ private void CheckMemberNameConflicts(DiagnosticBag diagnostics)`
`1567`	`1567`	`// following a field of the same name, or a field and a nested type of the same name.`
`1568`	`1568`	`//`
`1569`	`1569`
`1570`		`- if ((object)lastSym != null)`
	`1570`	`+ if ((object?)lastSym != null)`
`1571`	`1571`	`{`
`1572`	`1572`	`if (symbol.Kind != SymbolKind.Method \|\| lastSym.Kind != SymbolKind.Method)`
`1573`	`1573`	`{`
Original file line number	Diff line number	Diff line change
`@@ -91,6 +91,7 @@ public class TestAnalyzer : DiagnosticAnalyzer`
`91`	`91`	`new SyntaxTree[] { CSharp.SyntaxFactory.ParseSyntaxTree(analyzerSource) },`
`92`	`92`	`new MetadataReference[]`
`93`	`93`	`{`
	`94`	`+ TestMetadata.NetStandard20.mscorlib,`
`94`	`95`	`TestMetadata.NetStandard20.netstandard,`
`95`	`96`	`TestMetadata.NetStandard20.SystemRuntime,`
`96`	`97`	`MetadataReference.CreateFromFile(immutable.Path),`
Original file line number	Diff line number	Diff line change
`@@ -12,7 +12,10 @@ internal static class StaticCast<T>`
`12`	`12`	`{`
`13`	`13`	`internal static ImmutableArray<T> From<TDerived>(ImmutableArray<TDerived> from) where TDerived : class?, T`
`14`	`14`	`{`
	`15`	`+ // Remove the pragma when we get a version with https://github.com/dotnet/runtime/issues/39799 fixed`
	`16`	`+#pragma warning disable CS8634`
`15`	`17`	`return ImmutableArray<T>.CastUp(from);`
	`18`	`+#pragma warning restore CS8634`
`16`	`19`	`}`
`17`	`20`	`}`
`18`	`21`	`}`