Order APIs case-insensitive with case-sensitive fallback

Author: sharwell

src/PublicApiAnalyzers/Core/CodeFixes/DeclarePublicApiFix.cs

@@ -115,7 +115,7 @@ static void insertInList(List<string> list, string name)
             {
                 for (int i = 0; i < list.Count; i++)
                 {
-                    if (string.Compare(name, list[i], StringComparison.Ordinal) < 0)
+                    if (IgnoreCaseWhenPossibleComparer.Instance.Compare(name, list[i]) < 0)
                     {
                         list.Insert(i, name);
                         return;
@@ -231,7 +231,7 @@ await publicSurfaceAreaAdditionalDocument.GetTextAsync(cancellationToken).Config
                             .Where(d => d.Location.IsInSource)
                             .GroupBy(d => d.Location.SourceTree);
 
-                    var newSymbolNames = new SortedSet<string>();
+                    var newSymbolNames = new SortedSet<string>(IgnoreCaseWhenPossibleComparer.Instance);
                     var symbolNamesToRemoveBuilder = PooledHashSet<string>.GetInstance();
 
                     foreach (IGrouping<SyntaxTree, Diagnostic> grouping in groupedDiagnostics)
@@ -358,5 +358,23 @@ private class PublicSurfaceAreaFixAllProvider : FixAllProvider
                 return new FixAllAdditionalDocumentChangeAction(title, fixAllContext.Solution, diagnosticsToFix);
             }
         }
+
+        private sealed class IgnoreCaseWhenPossibleComparer : IComparer<string>
+        {
+            public static readonly IgnoreCaseWhenPossibleComparer Instance = new();
+
+            private IgnoreCaseWhenPossibleComparer()
+            {
+            }
+
+            public int Compare(string x, string y)
+            {
+                var result = StringComparer.OrdinalIgnoreCase.Compare(x, y);
+                if (result == 0)
+                    result = StringComparer.Ordinal.Compare(x, y);
+
+                return result;
+            }
+        }
     }
 }

src/PublicApiAnalyzers/UnitTests/DeclarePublicApiAnalyzerTests.cs

@@ -1757,6 +1757,35 @@ public class {|RS0016:{|RS0016:C2|}|} { }
             await VerifyCSharpAdditionalFileFixAsync(source, shippedText, unshippedText, fixedUnshippedText);
         }
 
+        [Fact]
+        public async Task TestMultipleMissingTypeAndMember_CaseSensitiveFix()
+        {
+            var source = @"
+public class {|RS0016:C|}
+{
+    private C() { }
+    public int {|RS0016:Field_A|};
+    public int {|RS0016:Field_b|};
+    public int {|RS0016:Field_C|};
+    public int {|RS0016:Field_d|};
+}
+
+public class {|RS0016:{|RS0016:C2|}|} { }
+";
+
+            var shippedText = @"";
+            var unshippedText = @"";
+            var fixedUnshippedText = @"C
+C.Field_A -> int
+C.Field_b -> int
+C.Field_C -> int
+C.Field_d -> int
+C2
+C2.C2() -> void";
+
+            await VerifyCSharpAdditionalFileFixAsync(source, shippedText, unshippedText, fixedUnshippedText);
+        }
+
         [Fact]
         public async Task TestChangingMethodSignatureForAnUnshippedMethod_Fix()
         {