SA1010 now properly supports index initializers

Author: vweijsters

StyleCop.Analyzers/StyleCop.Analyzers.Test/SpacingRules/SA1010UnitTests.cs

@@ -161,6 +161,28 @@ public int this [ [CLSCompliant(true)]int index]
             await this.VerifyCSharpFixAsync(testCode, ExpectedCode).ConfigureAwait(false);
         }
 
+        /// <summary>
+        /// Verify that index initializers are properly handled.
+        /// Regression test for https://github.com/DotNetAnalyzers/StyleCopAnalyzers/issues/1617
+        /// </summary>
+        /// <returns>A <see cref="Task"/> representing the asynchronous unit test.</returns>
+        [Fact]
+        public async Task VerifyIndexInitializerAsync()
+        {
+            var testCode = @"using System.Collections.Generic;
+
+public class TestClass
+{
+    public void TestMethod(IDictionary<ulong, string> items)
+    {
+        var test = new Dictionary<ulong, string>(items) { [100] = ""100"" };
+    }
+}
+";
+
+            await this.VerifyCSharpDiagnosticAsync(testCode, EmptyDiagnosticResults, CancellationToken.None).ConfigureAwait(false);
+        }
+
         /// <inheritdoc/>
         protected override IEnumerable<DiagnosticAnalyzer> GetCSharpDiagnosticAnalyzers()
         {

StyleCop.Analyzers/StyleCop.Analyzers/SpacingRules/SA1010OpeningSquareBracketsMustBeSpacedCorrectly.cs

@@ -92,7 +92,7 @@ private static void HandleOpenBracketToken(SyntaxTreeAnalysisContext context, Sy
             bool followedBySpace = token.IsFollowedByWhitespace();
             bool lastInLine = token.IsLastInLine();
 
-            if (!firstInLine && precededBySpace && !ignorePrecedingSpaceProblem)
+            if (!firstInLine && precededBySpace && !ignorePrecedingSpaceProblem && !IsPartOfIndexInitializer(token))
             {
                 // Opening square bracket must {not be preceded} by a space.
                 context.ReportDiagnostic(Diagnostic.Create(Descriptor, token.GetLocation(), TokenSpacingCodeFixProvider.RemovePreceding, "not be preceded"));
@@ -104,5 +104,21 @@ private static void HandleOpenBracketToken(SyntaxTreeAnalysisContext context, Sy
                 context.ReportDiagnostic(Diagnostic.Create(Descriptor, token.GetLocation(), TokenSpacingCodeFixProvider.RemoveFollowing, "not be followed"));
             }
         }
+
+        private static bool IsPartOfIndexInitializer(SyntaxToken token)
+        {
+            var currentParent = token.Parent;
+            while (currentParent != null)
+            {
+                if (currentParent.IsKind(SyntaxKind.ImplicitElementAccess))
+                {
+                    return true;
+                }
+
+                currentParent = currentParent.Parent;
+            }
+
+            return false;
+        }
     }
 }