Merge pull request #18024 from CyrusNajmabadi/lessHardcoding

Use less hardcoding of type-names when possible.

src/Features/CSharp/Portable/CodeFixes/Iterator/CSharpAddYieldCodeFixProvider.cs

 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+using System.Collections;
+using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Composition;
 using System.Linq;
@@ -96,10 +98,10 @@ private bool TryGetMethodReturnType(SyntaxNode node, SemanticModel model, Cancel
 
         private bool IsCorrectTypeForYieldReturn(ITypeSymbol typeArgument, ITypeSymbol returnExpressionType, ITypeSymbol methodReturnType, SemanticModel model)
         {
-            var ienumerableSymbol = model.Compilation.GetTypeByMetadataName("System.Collections.IEnumerable");
-            var ienumeratorSymbol = model.Compilation.GetTypeByMetadataName("System.Collections.IEnumerator");
-            var ienumerableGenericSymbol = model.Compilation.GetTypeByMetadataName("System.Collections.Generic.IEnumerable`1");
-            var ienumeratorGenericSymbol = model.Compilation.GetTypeByMetadataName("System.Collections.Generic.IEnumerator`1");
+            var ienumerableSymbol = model.Compilation.GetTypeByMetadataName(typeof(IEnumerable).FullName);
+            var ienumeratorSymbol = model.Compilation.GetTypeByMetadataName(typeof(IEnumerator).FullName);
+            var ienumerableGenericSymbol = model.Compilation.GetTypeByMetadataName(typeof(IEnumerable<>).FullName);
+            var ienumeratorGenericSymbol = model.Compilation.GetTypeByMetadataName(typeof(IEnumerator<>).FullName);
 
             if (ienumerableGenericSymbol == null ||
                 ienumerableSymbol == null ||
@@ -168,8 +170,8 @@ private bool CanConvertTypes(ITypeSymbol typeArgument, ITypeSymbol returnExpress
 
         private bool IsCorrectTypeForYieldReturn(ITypeSymbol returnExpressionType, ITypeSymbol methodReturnType, SemanticModel model)
         {
-            var ienumerableSymbol = model.Compilation.GetTypeByMetadataName("System.Collections.IEnumerable");
-            var ienumeratorSymbol = model.Compilation.GetTypeByMetadataName("System.Collections.IEnumerator");
+            var ienumerableSymbol = model.Compilation.GetTypeByMetadataName(typeof(IEnumerable).FullName);
+            var ienumeratorSymbol = model.Compilation.GetTypeByMetadataName(typeof(IEnumerator).FullName);
 
             if (ienumerableSymbol == null ||
                     ienumeratorSymbol == null)

src/Features/CSharp/Portable/CodeFixes/Iterator/CSharpChangeToIEnumerableCodeFixProvider.cs

 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+using System.Collections;
+using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Composition;
 using System.Linq;
@@ -105,8 +107,8 @@ protected override async Task<CodeAction> GetCodeFixAsync(SyntaxNode root, Synta
 
         private static bool TryGetIEnumerableSymbols(SemanticModel model, out INamedTypeSymbol ienumerableSymbol, out INamedTypeSymbol ienumerableGenericSymbol)
         {
-            ienumerableSymbol = model.Compilation.GetTypeByMetadataName("System.Collections.IEnumerable");
-            ienumerableGenericSymbol = model.Compilation.GetTypeByMetadataName("System.Collections.Generic.IEnumerable`1");
+            ienumerableSymbol = model.Compilation.GetTypeByMetadataName(typeof(IEnumerable).FullName);
+            ienumerableGenericSymbol = model.Compilation.GetTypeByMetadataName(typeof(IEnumerable<>).FullName);
 
             if (ienumerableGenericSymbol == null ||
                 ienumerableSymbol == null)

src/Features/CSharp/Portable/Completion/CompletionProviders/DeclarationNameCompletionProvider.cs

@@ -142,10 +142,11 @@ private ITypeSymbol UnwrapType(ITypeSymbol type, Compilation compilation)
                         return UnwrapType(namedType.TypeArguments[0], compilation);
                 }
 
-                var taskOfTType = compilation.GetTypeByMetadataName("System.Threading.Tasks.Task`1");
-                var valueTaskType = compilation.GetTypeByMetadataName("System.Threading.Tasks.ValueTask`1");
-                if (originalDefinition == taskOfTType
-                    || originalDefinition == valueTaskType)
+                var taskOfTType = compilation.TaskOfTType();
+                var valueTaskType = compilation.ValueTaskOfTType();
+
+                if (originalDefinition == taskOfTType ||
+                    originalDefinition == valueTaskType)
                 {
                     return UnwrapType(namedType.TypeArguments[0], compilation);
                 }

src/Features/CSharp/Portable/InlineDeclaration/CSharpInlineDeclarationDiagnosticAnalyzer.cs

@@ -3,6 +3,7 @@
 using System;
 using System.Collections.Immutable;
 using System.Linq;
+using System.Linq.Expressions;
 using System.Threading;
 using Microsoft.CodeAnalysis.CodeStyle;
 using Microsoft.CodeAnalysis.CSharp.Extensions;
@@ -46,7 +47,7 @@ protected override void InitializeWorker(AnalysisContext context)
             context.RegisterCompilationStartAction(compilationContext =>
             {
                 var compilation = compilationContext.Compilation;
-                var expressionTypeOpt = compilation.GetTypeByMetadataName("System.Linq.Expressions.Expression`1");
+                var expressionTypeOpt = compilation.GetTypeByMetadataName(typeof(Expression<>).FullName);
                 compilationContext.RegisterSyntaxNodeAction(
                     syntaxContext => AnalyzeSyntaxNode(syntaxContext, expressionTypeOpt), SyntaxKind.Argument);
             });

src/Features/Core/Portable/CodeFixes/Async/AbstractAddAwaitCodeFixProvider.cs

@@ -5,6 +5,7 @@
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.CodeActions;
+using Microsoft.CodeAnalysis.Shared.Extensions;
 
 namespace Microsoft.CodeAnalysis.CodeFixes.Async
 {
@@ -42,7 +43,7 @@ internal abstract partial class AbstractAddAwaitCodeFixProvider : AbstractAsyncC
         protected static bool TryGetTaskType(SemanticModel semanticModel, out INamedTypeSymbol taskType)
         {
             var compilation = semanticModel.Compilation;
-            taskType = compilation.GetTypeByMetadataName("System.Threading.Tasks.Task");
+            taskType = compilation.TaskType();
             return taskType != null;
         }
 

src/Features/Core/Portable/EditAndContinue/AbstractEditAndContinueAnalyzer.cs

@@ -2550,7 +2550,7 @@ private static bool HasBackingField(IEventSymbol @event)
 
             if (layoutAttribute == null)
             {
-                layoutAttribute = model.Compilation.GetTypeByMetadataName("System.Runtime.InteropServices.StructLayoutAttribute");
+                layoutAttribute = model.Compilation.GetTypeByMetadataName(typeof(StructLayoutAttribute).FullName);
                 if (layoutAttribute == null)
                 {
                     return false;

src/Features/Core/Portable/ExtractMethod/MethodExtractor.Analyzer.cs

@@ -544,7 +544,7 @@ private bool WellKnownFrameworkValueType(Compilation compilation, ITypeSymbol ty
                     return false;
                 }
 
-                var cancellationTokenType = compilation.GetTypeByMetadataName("System.Threading.CancellationToken");
+                var cancellationTokenType = compilation.GetTypeByMetadataName(typeof(CancellationToken).FullName);
                 if (cancellationTokenType != null && cancellationTokenType.Equals(type))
                 {
                     return true;

src/Features/Core/Portable/MakeMethodAsynchronous/AbstractMakeMethodAsynchronousCodeFixProvider.cs

@@ -75,9 +75,9 @@ public override async Task RegisterCodeFixesAsync(CodeFixContext context)
 
         private (INamedTypeSymbol taskType, INamedTypeSymbol taskOfTType, INamedTypeSymbol valueTaskOfTTypeOpt) GetTaskTypes(Compilation compilation)
         {
-            var taskType = compilation.GetTypeByMetadataName("System.Threading.Tasks.Task");
-            var taskOfTType = compilation.GetTypeByMetadataName("System.Threading.Tasks.Task`1");
-            var valueTaskOfTType = compilation.GetTypeByMetadataName("System.Threading.Tasks.ValueTask`1");
+            var taskType = compilation.TaskType();
+            var taskOfTType = compilation.TaskOfTType();
+            var valueTaskOfTType = compilation.ValueTaskOfTType();
 
             return (taskType, taskOfTType, valueTaskOfTType);
         }

src/Features/Core/Portable/MakeMethodSynchronous/AbstractMakeMethodSynchronousCodeFixProvider.cs

@@ -88,8 +88,8 @@ private async Task<Solution> RenameThenRemoveAsyncTokenAsync(Document document,
             Document document, IMethodSymbol methodSymbolOpt, SyntaxNode node, CancellationToken cancellationToken)
         {
             var compilation = await document.Project.GetCompilationAsync(cancellationToken).ConfigureAwait(false);
-            var taskType = compilation.GetTypeByMetadataName("System.Threading.Tasks.Task");
-            var taskOfTType = compilation.GetTypeByMetadataName("System.Threading.Tasks.Task`1");
+            var taskType = compilation.TaskType();
+            var taskOfTType = compilation.TaskOfTType();
 
             var annotation = new SyntaxAnnotation();
             var newNode = RemoveAsyncTokenAndFixReturnType(methodSymbolOpt, node, taskType, taskOfTType)

src/Features/Core/Portable/UseCoalesceExpression/AbstractUseCoalesceExpressionForNullableDiagnosticAnalyzer.cs

@@ -108,7 +108,7 @@ private void AnalyzeSyntax(SyntaxNodeAnalysisContext context)
             // actually looking at something Nullable (and not some type that uses a similar 
             // syntactic pattern).
             var semanticModel = context.SemanticModel;
-            var nullableType = semanticModel.Compilation.GetTypeByMetadataName("System.Nullable`1");
+            var nullableType = semanticModel.Compilation.GetTypeByMetadataName(typeof(Nullable<>).FullName);
             if (nullableType == null)
             {
                 return;

src/Features/Core/Portable/UseCollectionInitializer/AbstractUseCollectionInitializerDiagnosticAnalyzer.cs

 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 using System;
+using System.Collections;
 using System.Collections.Immutable;
 using Microsoft.CodeAnalysis.CodeStyle;
 using Microsoft.CodeAnalysis.Diagnostics;
@@ -44,7 +45,7 @@ protected override void InitializeWorker(AnalysisContext context)
 
         private void OnCompilationStart(CompilationStartAnalysisContext context)
         {
-            var ienumerableType = context.Compilation.GetTypeByMetadataName("System.Collections.IEnumerable") as INamedTypeSymbol;
+            var ienumerableType = context.Compilation.GetTypeByMetadataName(typeof(IEnumerable).FullName);
             if (ienumerableType != null)
             {
                 context.RegisterSyntaxNodeAction(

src/Features/VisualBasic/Portable/CodeFixes/Iterator/VisualBasicConvertToIteratorCodeFixProvider.vb

@@ -54,7 +54,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.CodeFixes.Iterator
             End If
 
             ' Check that return type of containing method is convertible to IEnumerable
-            Dim ienumerableSymbol As INamedTypeSymbol = model.Compilation.GetTypeByMetadataName("System.Collections.Generic.IEnumerable`1")
+            Dim ienumerableSymbol = model.Compilation.GetTypeByMetadataName(GetType(IEnumerable(Of)).FullName)
             If ienumerableSymbol Is Nothing Then
                 Return Nothing
             End If

src/Workspaces/Core/Portable/Shared/Extensions/ICodeDefinitionFactoryExtensions_CreateEqualsMethod.cs

@@ -51,7 +51,7 @@ internal static partial class ICodeDefinitionFactoryExtensions
             IEnumerable<ISymbol> members,
             CancellationToken cancellationToken)
         {
-            var iequatableType = compilation.GetTypeByMetadataName("System.IEquatable`1");
+            var iequatableType = compilation.GetTypeByMetadataName(typeof(IEquatable<>).FullName);
             var statements = ArrayBuilder<SyntaxNode>.GetInstance();
 
             // Come up with a good name for the local variable we're going to compare against.

src/Workspaces/Core/Portable/Shared/Extensions/ICompilationExtensions.cs

 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
+using System;
+using System.Collections.Generic;
 using System.Collections.Immutable;
+using System.ComponentModel;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+using System.Threading.Tasks;
 
 namespace Microsoft.CodeAnalysis.Shared.Extensions
 {
@@ -45,108 +52,69 @@ public static ImmutableArray<IAssemblySymbol> GetReferencedAssemblySymbols(this
         }
 
         public static INamedTypeSymbol AttributeType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.Attribute");
-        }
+            => compilation.GetTypeByMetadataName(typeof(Attribute).FullName);
 
         public static INamedTypeSymbol ExceptionType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.Exception");
-        }
+            => compilation.GetTypeByMetadataName(typeof(Exception).FullName);
 
         public static INamedTypeSymbol DesignerCategoryAttributeType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.ComponentModel.DesignerCategoryAttribute");
-        }
+            => compilation.GetTypeByMetadataName("System.ComponentModel.DesignerCategoryAttribute");
 
         public static INamedTypeSymbol DesignerGeneratedAttributeType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("Microsoft.VisualBasic.CompilerServices.DesignerGeneratedAttribute");
-        }
+            => compilation.GetTypeByMetadataName("Microsoft.VisualBasic.CompilerServices.DesignerGeneratedAttribute");
 
         public static INamedTypeSymbol HideModuleNameAttribute(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("Microsoft.VisualBasic.HideModuleNameAttribute");
-        }
+            => compilation.GetTypeByMetadataName("Microsoft.VisualBasic.HideModuleNameAttribute");
 
         public static INamedTypeSymbol EventArgsType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.EventArgs");
-        }
+            => compilation.GetTypeByMetadataName(typeof(EventArgs).FullName);
 
         public static INamedTypeSymbol NotImplementedExceptionType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.NotImplementedException");
-        }
+            => compilation.GetTypeByMetadataName(typeof(NotImplementedException).FullName);
 
         public static INamedTypeSymbol EqualityComparerOfTType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.Collections.Generic.EqualityComparer`1");
-        }
+            => compilation.GetTypeByMetadataName(typeof(EqualityComparer<>).FullName);
 
         public static INamedTypeSymbol ActionType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.Action");
-        }
+            => compilation.GetTypeByMetadataName(typeof(Action).FullName);
 
         public static INamedTypeSymbol ExpressionOfTType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.Linq.Expressions.Expression`1");
-        }
+            => compilation.GetTypeByMetadataName("System.Linq.Expressions.Expression`1");
 
         public static INamedTypeSymbol EditorBrowsableAttributeType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.ComponentModel.EditorBrowsableAttribute");
-        }
+            => compilation.GetTypeByMetadataName(typeof(EditorBrowsableAttribute).FullName);
 
         public static INamedTypeSymbol EditorBrowsableStateType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.ComponentModel.EditorBrowsableState");
-        }
+            => compilation.GetTypeByMetadataName(typeof(EditorBrowsableState).FullName);
 
         public static INamedTypeSymbol TaskType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.Threading.Tasks.Task");
-        }
+            => compilation.GetTypeByMetadataName(typeof(Task).FullName);
 
         public static INamedTypeSymbol TaskOfTType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.Threading.Tasks.Task`1");
-        }
+            => compilation.GetTypeByMetadataName(typeof(Task<>).FullName);
+
+        public static INamedTypeSymbol ValueTaskOfTType(this Compilation compilation)
+            => compilation.GetTypeByMetadataName("System.Threading.Tasks.ValueTask`1");
 
         public static INamedTypeSymbol IEnumerableOfTType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.Collections.Generic.IEnumerable`1");
-        }
+            => compilation.GetTypeByMetadataName(typeof(IEnumerable<>).FullName);
 
         public static INamedTypeSymbol SerializableAttributeType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.SerializableAttribute");
-        }
+            => compilation.GetTypeByMetadataName("System.SerializableAttribute");
 
         public static INamedTypeSymbol CoClassType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.Runtime.InteropServices.CoClassAttribute");
-        }
+            => compilation.GetTypeByMetadataName(typeof(CoClassAttribute).FullName);
 
         public static INamedTypeSymbol ComAliasNameAttributeType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.Runtime.InteropServices.ComAliasNameAttribute");
-        }
+            => compilation.GetTypeByMetadataName("System.Runtime.InteropServices.ComAliasNameAttribute");
 
         public static INamedTypeSymbol SuppressMessageAttributeType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.Diagnostics.CodeAnalysis.SuppressMessageAttribute");
-        }
+            => compilation.GetTypeByMetadataName(typeof(SuppressMessageAttribute).FullName);
 
         public static INamedTypeSymbol TupleElementNamesAttributeType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.Runtime.CompilerServices.TupleElementNamesAttribute");
-        }
+            => compilation.GetTypeByMetadataName(typeof(TupleElementNamesAttribute).FullName);
 
         public static INamedTypeSymbol DynamicAttributeType(this Compilation compilation)
-        {
-            return compilation.GetTypeByMetadataName("System.Runtime.CompilerServices.DynamicAttribute");
-        }
-     }
-}
+            => compilation.GetTypeByMetadataName("System.Runtime.CompilerServices.DynamicAttribute");
+    }
+}
\ No newline at end of file

src/Workspaces/VisualBasic/Portable/CodeCleanup/AsyncOrIteratorFunctionReturnTypeFixer.vb

@@ -6,9 +6,6 @@ Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
 
 Namespace Microsoft.CodeAnalysis.CodeCleanup
     Friend Module AsyncOrIteratorFunctionReturnTypeFixer
-        Private Const s_system_Threading_Tasks_Task_Name As String = "System.Threading.Tasks.Task"
-        Private Const s_system_Threading_Tasks_Task_Of_T_Name As String = "System.Threading.Tasks.Task`1"
-        Private Const s_system_Collections_IEnumerable_Name As String = "System.Collections.IEnumerable"
 
         Public Function RewriteMethodStatement(func As MethodStatementSyntax, semanticModel As SemanticModel, cancellationToken As CancellationToken) As MethodStatementSyntax
             Return RewriteMethodStatement(func, semanticModel, oldFunc:=func, cancellationToken:=cancellationToken)
@@ -85,7 +82,7 @@ Namespace Microsoft.CodeAnalysis.CodeCleanup
                 Return False
             End If
 
-            Dim taskType = semanticModel.Compilation.GetTypeByMetadataName(s_system_Threading_Tasks_Task_Name)
+            Dim taskType = semanticModel.Compilation.GetTypeByMetadataName(GetType(Task).FullName)
             If asClauseOpt Is Nothing Then
                 ' Without an AsClause: Async functions are pretty listed to return Task.
                 If taskType IsNot Nothing AndAlso parameterListOpt IsNot Nothing Then
@@ -95,7 +92,7 @@ Namespace Microsoft.CodeAnalysis.CodeCleanup
             Else
                 '   2) With an AsClause: If the return type R is a valid non-error type, pretty list as follows:
                 '       (a) Async functions: If R is not Task or Task(Of T) or an instantiation of Task(Of T), pretty list return type to Task(Of R).
-                Dim taskOfT = semanticModel.Compilation.GetTypeByMetadataName(s_system_Threading_Tasks_Task_Of_T_Name)
+                Dim taskOfT = semanticModel.Compilation.GetTypeByMetadataName(GetType(Task(Of)).FullName)
                 Dim returnType = semanticModel.GetTypeInfo(oldAsClauseOpt.Type, cancellationToken).Type
                 If returnType IsNot Nothing AndAlso Not returnType.IsErrorType() AndAlso
                     taskType IsNot Nothing AndAlso taskOfT IsNot Nothing AndAlso
@@ -119,7 +116,7 @@ Namespace Microsoft.CodeAnalysis.CodeCleanup
 
             If asClauseOpt Is Nothing Then
                 ' Without an AsClause: Iterator functions are pretty listed to return IEnumerable.
-                Dim iEnumerableType = semanticModel.Compilation.GetTypeByMetadataName(s_system_Collections_IEnumerable_Name)
+                Dim iEnumerableType = semanticModel.Compilation.GetTypeByMetadataName(GetType(IEnumerable).FullName)
                 If iEnumerableType IsNot Nothing Then
                     GenerateFunctionAsClause(iEnumerableType, parameterListOpt, asClauseOpt, semanticModel, position)
                     Return True

src/Workspaces/VisualBasic/Portable/LanguageServices/VisualBasicTypeInferenceService.TypeInferrer.vb

@@ -406,8 +406,8 @@ Namespace Microsoft.CodeAnalysis.VisualBasic
 
                 Dim types = InferTypes(awaitExpression, filterUnusable:=False)
 
-                Dim task = Me.Compilation.GetTypeByMetadataName("System.Threading.Tasks.Task")
-                Dim taskOfT = Me.Compilation.GetTypeByMetadataName("System.Threading.Tasks.Task`1")
+                Dim task = Me.Compilation.GetTypeByMetadataName(GetType(Task).FullName)
+                Dim taskOfT = Me.Compilation.GetTypeByMetadataName(GetType(Task(Of)).FullName)
 
                 If task Is Nothing OrElse taskOfT Is Nothing Then
                     Return SpecializedCollections.EmptyEnumerable(Of TypeInferenceInfo)()