Final fixes after rebasing

Author: vweijsters

StyleCop.Analyzers/StyleCop.Analyzers.CodeFixes/ReadabilityRules/SA1130CodeFixProvider.cs

@@ -209,8 +209,7 @@ private static ImmutableArray<string> GetEqualsArgumentList(SemanticModel semant
         private static ImmutableArray<string> GetMemberReturnTypeArgumentList(SemanticModel semanticModel, AnonymousMethodExpressionSyntax anonymousMethod)
         {
             var enclosingSymbol = semanticModel.GetEnclosingSymbol(anonymousMethod.Parent.SpanStart);
-            var returnType = ((IMethodSymbol)enclosingSymbol).ReturnType as INamedTypeSymbol;
-            return (returnType == null) ? ImmutableArray<string>.Empty : returnType.DelegateInvokeMethod.Parameters.Select(ps => ps.Name).ToImmutableArray();
+            return !(((IMethodSymbol)enclosingSymbol).ReturnType is INamedTypeSymbol returnType) ? ImmutableArray<string>.Empty : returnType.DelegateInvokeMethod.Parameters.Select(ps => ps.Name).ToImmutableArray();
         }
 
         private static List<ParameterSyntax> GenerateUniqueParameterNames(SemanticModel semanticModel, AnonymousMethodExpressionSyntax anonymousMethod, ImmutableArray<string> argumentNames)

StyleCop.Analyzers/StyleCop.Analyzers/Lightup/SyntaxFactsEx.cs

@@ -16,18 +16,17 @@ internal static class SyntaxFactsEx
 
         static SyntaxFactsEx()
         {
-            Func<SyntaxNode, string> fallbackAccessor =
-                syntax =>
+            string FallbackAccessor(SyntaxNode syntax)
+            {
+                if (syntax == null)
                 {
-                    if (syntax == null)
-                    {
-                        // Unlike an extension method which would throw ArgumentNullException here, the light-up
-                        // behavior needs to match behavior of the underlying property.
-                        throw new NullReferenceException();
-                    }
+                    // Unlike an extension method which would throw ArgumentNullException here, the light-up
+                    // behavior needs to match behavior of the underlying property.
+                    throw new NullReferenceException();
+                }
 
-                    return null;
-                };
+                return null;
+            }
 
             var tryGetInferredMemberNameMethod = typeof(SyntaxFacts).GetTypeInfo().GetDeclaredMethod(nameof(TryGetInferredMemberName));
             if (tryGetInferredMemberNameMethod is object)
@@ -41,7 +40,7 @@ static SyntaxFactsEx()
             }
             else
             {
-                TryGetInferredMemberNameAccessor = fallbackAccessor;
+                TryGetInferredMemberNameAccessor = FallbackAccessor;
             }
 
             var isReservedTupleElementNameMethod = typeof(SyntaxFacts).GetTypeInfo().GetDeclaredMethod(nameof(IsReservedTupleElementName));

StyleCop.Analyzers/StyleCop.Analyzers/NamingRules/SA1316TupleElementNamesShouldUseCorrectCasing.cs

@@ -108,7 +108,7 @@ private static void CheckName(SyntaxNodeAnalysisContext context, StyleCopSetting
         {
             var firstCharacterIsLower = char.IsLower(tupleElementName[0]);
 
-            bool reportDiagnostic = false;
+            bool reportDiagnostic;
             string fixedName;
 
             switch (settings.NamingRules.TupleElementNameCasing)

StyleCop.Analyzers/StyleCop.Analyzers/ReadabilityRules/SA1142ReferToTupleElementsByName.cs

@@ -51,8 +51,7 @@ private static void HandleSimpleMemberAccessExpression(SyntaxNodeAnalysisContext
 
             var memberAccessExpression = (MemberAccessExpressionSyntax)context.Node;
 
-            var fieldSymbol = context.SemanticModel.GetSymbolInfo(memberAccessExpression).Symbol as IFieldSymbol;
-            if (fieldSymbol == null)
+            if (!(context.SemanticModel.GetSymbolInfo(memberAccessExpression).Symbol is IFieldSymbol fieldSymbol))
             {
                 return;
             }