Merge pull request #39247 from dotnet/merges/master-to-features/stati…

…c-lambdas

Merge master to features/static-lambdas

src/Compilers/Core/Portable/Symbols/Accessibility.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 using Microsoft.CodeAnalysis.Text;
 
 namespace Microsoft.CodeAnalysis

src/Compilers/Core/Portable/Symbols/AnonymousTypes/CommonAnonymousTypeManager.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 namespace Microsoft.CodeAnalysis.Symbols
 {
     internal abstract class CommonAnonymousTypeManager

src/Compilers/Core/Portable/Symbols/Attributes/AttributeDescription.cs

@@ -1,9 +1,12 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 using System.Diagnostics;
 using Microsoft.CodeAnalysis.Text;
 using System.Reflection.Metadata;
 using System.Collections.Immutable;
+using Roslyn.Utilities;
 
 namespace Microsoft.CodeAnalysis
 {
@@ -18,9 +21,9 @@ internal struct AttributeDescription
 
         public AttributeDescription(string @namespace, string name, byte[][] signatures, bool matchIgnoringCase = false)
         {
-            Debug.Assert(@namespace != null);
-            Debug.Assert(name != null);
-            Debug.Assert(signatures != null);
+            RoslynDebug.Assert(@namespace != null);
+            RoslynDebug.Assert(name != null);
+            RoslynDebug.Assert(signatures != null);
 
             this.Namespace = @namespace;
             this.Name = name;

src/Compilers/Core/Portable/Symbols/Attributes/AttributeUsageInfo.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 using System;
 using System.Diagnostics;
 using Microsoft.CodeAnalysis.Collections;
@@ -167,11 +169,11 @@ internal object GetValidTargetsErrorArgument()
 
         private struct ValidTargetsStringLocalizableErrorArgument : IFormattable
         {
-            private readonly string[] _targetResourceIds;
+            private readonly string[]? _targetResourceIds;
 
             internal ValidTargetsStringLocalizableErrorArgument(string[] targetResourceIds)
             {
-                Debug.Assert(targetResourceIds != null);
+                RoslynDebug.Assert(targetResourceIds != null);
                 _targetResourceIds = targetResourceIds;
             }
 
@@ -180,7 +182,7 @@ public override string ToString()
                 return ToString(null, null);
             }
 
-            public string ToString(string format, IFormatProvider formatProvider)
+            public string ToString(string? format, IFormatProvider? formatProvider)
             {
                 var builder = PooledStringBuilder.GetInstance();
                 var culture = formatProvider as System.Globalization.CultureInfo;

src/Compilers/Core/Portable/Symbols/CommonAttributeDataExtensions.cs

@@ -1,18 +1,20 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 namespace Microsoft.CodeAnalysis
 {
     internal static class CommonAttributeDataExtensions
     {
-        public static bool TryGetGuidAttributeValue(this AttributeData attrData, out string guidString)
+        public static bool TryGetGuidAttributeValue(this AttributeData attrData, out string? guidString)
         {
             if (attrData.CommonConstructorArguments.Length == 1)
             {
-                object value = attrData.CommonConstructorArguments[0].Value;
+                object? value = attrData.CommonConstructorArguments[0].Value;
 
                 if (value == null || value is string)
                 {
-                    guidString = (string)value;
+                    guidString = (string?)value;
                     return true;
                 }
             }

src/Compilers/Core/Portable/Symbols/CustomModifier.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 using System;
 using Microsoft.CodeAnalysis.Emit;
 

src/Compilers/Core/Portable/Symbols/CustomModifiersTuple.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 using System.Collections.Immutable;
 
 namespace Microsoft.CodeAnalysis

src/Compilers/Core/Portable/Symbols/ISymbol.cs

@@ -1,8 +1,11 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 using System;
 using System.Collections.Generic;
 using System.Collections.Immutable;
+using System.Diagnostics.CodeAnalysis;
 using System.Globalization;
 using System.Runtime.CompilerServices;
 using System.Threading;
@@ -18,7 +21,7 @@ namespace Microsoft.CodeAnalysis
     /// change it in the future.
     /// </remarks>
     [InternalImplementationOnly]
-    public interface ISymbol : IEquatable<ISymbol>
+    public interface ISymbol : IEquatable<ISymbol?>
     {
         /// <summary>
         /// Gets the <see cref="SymbolKind"/> indicating what kind of symbol it is.
@@ -55,6 +58,7 @@ public interface ISymbol : IEquatable<ISymbol>
         /// </summary>
         string MetadataName { get; }
 
+#nullable disable // Skipped for now https://github.com/dotnet/roslyn/issues/39166
         /// <summary>
         /// Gets the <see cref="ISymbol"/> for the immediately containing symbol.
         /// </summary>
@@ -83,6 +87,7 @@ public interface ISymbol : IEquatable<ISymbol>
         /// symbol isn't contained in a namespace.
         /// </summary>
         INamespaceSymbol ContainingNamespace { get; }
+#nullable enable
 
         /// <summary>
         /// Gets a value indicating whether the symbol is the original definition. Returns false
@@ -201,7 +206,7 @@ public interface ISymbol : IEquatable<ISymbol>
         /// Returns the Documentation Comment ID for the symbol, or null if the symbol doesn't
         /// support documentation comments.
         /// </summary>
-        string GetDocumentationCommentId();
+        string? GetDocumentationCommentId();
 
         /// <summary>
         /// Gets the XML (as text) for the comment associated with the symbol.
@@ -210,14 +215,14 @@ public interface ISymbol : IEquatable<ISymbol>
         /// <param name="expandIncludes">Optionally, expand &lt;include&gt; elements.  No impact on non-source documentation comments.</param>
         /// <param name="cancellationToken">Token allowing cancellation of request.</param>
         /// <returns>The XML that would be written to the documentation file for the symbol.</returns>
-        string GetDocumentationCommentXml(CultureInfo preferredCulture = null, bool expandIncludes = false, CancellationToken cancellationToken = default(CancellationToken));
+        string? GetDocumentationCommentXml(CultureInfo? preferredCulture = null, bool expandIncludes = false, CancellationToken cancellationToken = default(CancellationToken));
 
         /// <summary>
         /// Converts the symbol to a string representation.
         /// </summary>
         /// <param name="format">Format or null for the default.</param>
         /// <returns>A formatted string representation of the symbol.</returns>
-        string ToDisplayString(SymbolDisplayFormat format = null);
+        string ToDisplayString(SymbolDisplayFormat? format = null);
 
         /// <summary>
         /// Convert a symbol to an array of string parts, each of which has a kind. Useful for
@@ -226,7 +231,7 @@ public interface ISymbol : IEquatable<ISymbol>
         /// <param name="format">Formatting rules - null implies
         /// SymbolDisplayFormat.ErrorMessageFormat.</param>
         /// <returns>A read-only array of string parts.</returns>
-        ImmutableArray<SymbolDisplayPart> ToDisplayParts(SymbolDisplayFormat format = null);
+        ImmutableArray<SymbolDisplayPart> ToDisplayParts(SymbolDisplayFormat? format = null);
 
         /// <summary>
         /// Convert a symbol to a string that can be displayed to the user. May be tailored to a
@@ -241,7 +246,7 @@ public interface ISymbol : IEquatable<ISymbol>
         string ToMinimalDisplayString(
             SemanticModel semanticModel,
             int position,
-            SymbolDisplayFormat format = null);
+            SymbolDisplayFormat? format = null);
 
         /// <summary>
         /// Convert a symbol to an array of string parts, each of which has a kind. May be tailored
@@ -256,7 +261,7 @@ string ToMinimalDisplayString(
         ImmutableArray<SymbolDisplayPart> ToMinimalDisplayParts(
             SemanticModel semanticModel,
             int position,
-            SymbolDisplayFormat format = null);
+            SymbolDisplayFormat? format = null);
 
         /// <summary>
         /// Indicates that this symbol uses metadata that cannot be supported by the language.
@@ -295,6 +300,6 @@ ImmutableArray<SymbolDisplayPart> ToMinimalDisplayParts(
         /// <param name="other">The other symbol to compare against</param>
         /// <param name="equalityComparer">The <see cref="SymbolEqualityComparer"/> to use when comparing symbols</param>
         /// <returns>True if the symbols are equivalent.</returns>
-        bool Equals(ISymbol other, SymbolEqualityComparer equalityComparer);
+        bool Equals([NotNullWhen(returnValue: true)] ISymbol? other, SymbolEqualityComparer equalityComparer);
     }
 }

src/Compilers/Core/Portable/Symbols/LanguageNames.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 namespace Microsoft.CodeAnalysis
 {
     /// <summary>

src/Compilers/Core/Portable/Symbols/ManagedKind.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 using System;
 
 namespace Microsoft.CodeAnalysis

src/Compilers/Core/Portable/Symbols/MethodKind.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 using Microsoft.CodeAnalysis.Text;
 
 namespace Microsoft.CodeAnalysis

src/Compilers/Core/Portable/Symbols/NamespaceKind.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 using Microsoft.CodeAnalysis.Text;
 
 namespace Microsoft.CodeAnalysis

src/Compilers/Core/Portable/Symbols/NullabilityInfo.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 using System;
 using System.Diagnostics;
 using Roslyn.Utilities;
@@ -31,7 +33,7 @@ internal NullabilityInfo(NullableAnnotation annotation, NullableFlowState flowSt
 
         private string GetDebuggerDisplay() => $"{{Annotation: {Annotation}, Flow State: {FlowState}}}";
 
-        public override bool Equals(object other) =>
+        public override bool Equals(object? other) =>
             other is NullabilityInfo info && Equals(info);
 
         public override int GetHashCode() =>

src/Compilers/Core/Portable/Symbols/NullableAnnotation.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 namespace Microsoft.CodeAnalysis
 {
     /// <summary>

src/Compilers/Core/Portable/Symbols/NullableFlowState.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 namespace Microsoft.CodeAnalysis
 {
     /// <summary>

src/Compilers/Core/Portable/Symbols/PlatformInvokeInformation.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 using System.Reflection;
 using System.Runtime.InteropServices;
 using Roslyn.Utilities;
@@ -11,11 +13,11 @@ namespace Microsoft.CodeAnalysis
     /// </summary>
     public sealed class DllImportData : Cci.IPlatformInvokeInformation
     {
-        private readonly string _moduleName;
-        private readonly string _entryPointName;            // null if unspecified, the name of the target method should be used
+        private readonly string? _moduleName;
+        private readonly string? _entryPointName;            // null if unspecified, the name of the target method should be used
         private readonly MethodImportAttributes _flags;
 
-        internal DllImportData(string moduleName, string entryPointName, MethodImportAttributes flags)
+        internal DllImportData(string? moduleName, string? entryPointName, MethodImportAttributes flags)
         {
             _moduleName = moduleName;
             _entryPointName = entryPointName;
@@ -25,15 +27,15 @@ internal DllImportData(string moduleName, string entryPointName, MethodImportAtt
         /// <summary>
         /// Module name. Null if value specified in the attribute is not valid.
         /// </summary>
-        public string ModuleName
+        public string? ModuleName
         {
             get { return _moduleName; }
         }
 
         /// <summary>
         /// Name of the native entry point or null if not specified (the effective name is the same as the name of the target method).
         /// </summary>
-        public string EntryPointName
+        public string? EntryPointName
         {
             get { return _entryPointName; }
         }

src/Compilers/Core/Portable/Symbols/RefKind.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 using System;
 using Roslyn.Utilities;
 

src/Compilers/Core/Portable/Symbols/SymbolEqualityComparer.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 using System;
 using System.Collections.Generic;
 using Microsoft.CodeAnalysis.Symbols;
@@ -9,7 +11,7 @@ namespace Microsoft.CodeAnalysis
     /// <summary>
     /// Allows for the comparison of two <see cref="ISymbol"/> instances
     /// </summary>
-    public sealed class SymbolEqualityComparer : IEqualityComparer<ISymbol>
+    public sealed class SymbolEqualityComparer : IEqualityComparer<ISymbol?>
     {
         /// <summary>
         /// Compares two <see cref="ISymbol"/> instances based on the default comparison rules, equivalent to calling <see cref="IEquatable{ISymbol}.Equals(ISymbol)"/>
@@ -37,7 +39,7 @@ private SymbolEqualityComparer(TypeCompareKind compareKind)
         /// <param name="x">The first symbol to compare</param>
         /// <param name="y">The second symbol to compare</param>
         /// <returns>True if the symbols are equivalent</returns>
-        public bool Equals(ISymbol x, ISymbol y)
+        public bool Equals(ISymbol? x, ISymbol? y)
         {
             if (x is null)
             {
@@ -53,11 +55,11 @@ public bool Equals(ISymbol x, ISymbol y)
             }
             else
             {
-                return x.Equals((object)y);
+                return x.Equals((object?)y);
             }
         }
 
-        public int GetHashCode(ISymbol obj)
+        public int GetHashCode(ISymbol? obj)
         {
             return obj?.GetHashCode() ?? 0;
         }

src/Compilers/Core/Portable/Symbols/SymbolKind.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 namespace Microsoft.CodeAnalysis
 {
     /// <summary>

src/Compilers/Core/Portable/Symbols/SymbolKindExtensions.cs

@@ -1,5 +1,7 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 using Roslyn.Utilities;
 
 namespace Microsoft.CodeAnalysis

src/Compilers/Core/Portable/Symbols/SymbolVisitor.cs

@@ -1,10 +1,12 @@
 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+#nullable enable
+
 namespace Microsoft.CodeAnalysis
 {
     public abstract class SymbolVisitor
     {
-        public virtual void Visit(ISymbol symbol)
+        public virtual void Visit(ISymbol? symbol)
         {
             symbol?.Accept(this);
         }