Ignore inferred tuple element name when explicit name is given

Author: Scott McGinness

StyleCop.Analyzers/StyleCop.Analyzers.Test.CSharp7/NamingRules/SA1316CSharp7UnitTests.cs

@@ -8,7 +8,6 @@ namespace StyleCop.Analyzers.Test.CSharp7.NamingRules
     using Microsoft.CodeAnalysis.Testing;
     using StyleCop.Analyzers.Lightup;
     using StyleCop.Analyzers.NamingRules;
-    using StyleCop.Analyzers.Settings.ObjectModel;
     using Xunit;
     using static StyleCop.Analyzers.Test.Verifiers.StyleCopCodeFixVerifier<
         StyleCop.Analyzers.NamingRules.SA1316TupleElementNamesShouldUseCorrectCasing,
@@ -170,6 +169,40 @@ public void TestMethod()
             await VerifyCSharpDiagnosticAsync(LanguageVersionEx.CSharp7_1, testCode, settings, DiagnosticResult.EmptyDiagnosticResults, CancellationToken.None).ConfigureAwait(false);
         }
 
+        /// <summary>
+        /// Validates the properly explicitly named tuple elements, even when using inferred tuple element names, will not produce diagnostics.
+        /// </summary>
+        /// <param name="settings">The test settings to use.</param>
+        /// <param name="tupleElementName1">The expected tuple element name for the first field.</param>
+        /// <param name="tupleElementName2">The expected tuple element name for the second field.</param>
+        /// <returns>A <see cref="Task"/> representing the asynchronous unit test.</returns>
+        [Theory]
+        [InlineData(CamelCaseInferredTestSettings, "elementName1", "elementName2", "ElementValue1", "ElementValue2")]
+        [InlineData(PascalCaseInferredTestSettings, "ElementName1", "ElementName2", "elementValue1", "elementValue2")]
+        public async Task ValidateProperCasedExplicitNamesEvenWithInferredTupleElementNamesAsync(string settings, string tupleElementName1, string tupleElementName2, string tupleInferred1, string tupleInferred2)
+        {
+            var testCode = $@"
+public class TestClass
+{{
+    public void TestMethod1()
+    {{
+        var {tupleInferred1} = 1;
+        var {tupleInferred2} = ""test"";
+        var tuple = ({tupleElementName1}: {tupleInferred1}, {tupleElementName2}: {tupleInferred2});
+    }}
+
+    public void TestMethod2()
+    {{
+        var {tupleInferred1} = 1;
+        var {tupleElementName2} = ""test"";
+        var tuple = ({tupleElementName1}: {tupleInferred1}, {tupleElementName2});
+    }}
+}}
+";
+
+            await VerifyCSharpDiagnosticAsync(LanguageVersionEx.CSharp7_1, testCode, settings, DiagnosticResult.EmptyDiagnosticResults, CancellationToken.None).ConfigureAwait(false);
+        }
+
         /// <summary>
         /// Validates the improperly named tuple element names will produce the expected diagnostics.
         /// </summary>

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

@@ -6,8 +6,6 @@ namespace StyleCop.Analyzers.NamingRules
     using System;
     using System.Collections.Immutable;
     using Microsoft.CodeAnalysis;
-    using Microsoft.CodeAnalysis.CSharp;
-    using Microsoft.CodeAnalysis.CSharp.Syntax;
     using Microsoft.CodeAnalysis.Diagnostics;
     using StyleCop.Analyzers.Helpers;
     using StyleCop.Analyzers.Lightup;
@@ -86,7 +84,7 @@ private static void HandleTupleExpressionAction(SyntaxNodeAnalysisContext contex
             var tupleExpression = (TupleExpressionSyntaxWrapper)context.Node;
             foreach (var argument in tupleExpression.Arguments)
             {
-                var inferredMemberName = SyntaxFactsEx.TryGetInferredMemberName(argument.Expression);
+                var inferredMemberName = SyntaxFactsEx.TryGetInferredMemberName(argument.NameColon?.Name ?? argument.Expression);
                 if (inferredMemberName != null)
                 {
                     CheckName(context, settings, inferredMemberName, argument.Expression.GetLocation(), false);