Fixed UsingCodeFixProvider

Author: vweijsters

StyleCop.Analyzers/StyleCop.Analyzers.CodeFixes/OrderingRules/UsingCodeFixProvider.UsingsSorter.cs

@@ -13,6 +13,7 @@ namespace StyleCop.Analyzers.OrderingRules
     using Microsoft.CodeAnalysis.CSharp;
     using Microsoft.CodeAnalysis.CSharp.Syntax;
     using StyleCop.Analyzers.Helpers;
+    using StyleCop.Analyzers.Helpers.ObjectPools;
     using StyleCop.Analyzers.Lightup;
     using StyleCop.Analyzers.Settings.ObjectModel;
 
@@ -377,7 +378,7 @@ private UsingDirectiveSyntax QualifyUsingDirective(UsingDirectiveSyntax usingDir
                             }
                             else if (namedTypeSymbol.IsTupleType())
                             {
-                                fullName = namedTypeSymbol.TupleUnderlyingType().ToDisplayString(SymbolDisplayFormat.FullyQualifiedFormat);
+                                fullName = namedTypeSymbol.TupleUnderlyingTypeOrSelf().ToFullyQualifiedValueTupleDisplayString();
                             }
                             else
                             {

StyleCop.Analyzers/StyleCop.Analyzers/Helpers/NamedTypeHelpers.cs

@@ -9,6 +9,8 @@ namespace StyleCop.Analyzers.Helpers
     using Microsoft.CodeAnalysis.CSharp;
     using Microsoft.CodeAnalysis.CSharp.Syntax;
 
+    using StyleCop.Analyzers.Lightup;
+
     internal static class NamedTypeHelpers
     {
         internal static bool IsNativeMethodsClass(INamedTypeSymbol type)
@@ -179,5 +181,8 @@ internal static bool IsImplementingAnInterfaceMember(ISymbol memberSymbol)
                 .Select(typeSymbol.FindImplementationForInterfaceMember)
                 .Any(x => memberSymbol.Equals(x));
         }
+
+        internal static INamedTypeSymbol TupleUnderlyingTypeOrSelf(this INamedTypeSymbol tupleSymbol)
+            => tupleSymbol.TupleUnderlyingType() ?? tupleSymbol;
     }
 }

StyleCop.Analyzers/StyleCop.Analyzers/Helpers/SymbolNameHelpers.cs

@@ -7,6 +7,7 @@ namespace StyleCop.Analyzers.Helpers
     using Microsoft.CodeAnalysis;
     using Microsoft.CodeAnalysis.CSharp;
     using Microsoft.CodeAnalysis.CSharp.Syntax;
+
     using StyleCop.Analyzers.Lightup;
 
     /// <summary>
@@ -35,6 +36,40 @@ public static string ToQualifiedString(this ISymbol symbol, NameSyntax name)
             return ObjectPools.StringBuilderPool.ReturnAndFree(builder);
         }
 
+        /// <summary>
+        /// Generates the fully qualified System.ValueTuple based name for the given tuple type.
+        /// </summary>
+        /// <param name="tupleSymbol">The tuple symbol.</param>
+        /// <returns>The generated fully qualified display string.</returns>
+        public static string ToFullyQualifiedValueTupleDisplayString(this INamedTypeSymbol tupleSymbol)
+        {
+            var tupleElements = tupleSymbol.TupleElements();
+            if (tupleElements.IsDefault)
+            {
+                return tupleSymbol.ToDisplayString(SymbolDisplayFormat.FullyQualifiedFormat);
+            }
+            else
+            {
+                var builder = ObjectPools.StringBuilderPool.Allocate();
+
+                builder.Append("global::System.ValueTuple<");
+
+                for (var i = 0; i < tupleElements.Length; i++)
+                {
+                    if (i > 0)
+                    {
+                        builder.Append(", ");
+                    }
+
+                    builder.Append(tupleElements[i].Type.ToDisplayString(SymbolDisplayFormat.FullyQualifiedFormat));
+                }
+
+                builder.Append(">");
+
+                return ObjectPools.StringBuilderPool.ReturnAndFree(builder);
+            }
+        }
+
         private static bool AppendQualifiedSymbolName(StringBuilder builder, ISymbol symbol, TypeSyntax type)
         {
             switch (symbol.Kind)