Update SA1202 for partial methods

Author: sharwell

StyleCop.Analyzers/StyleCop.Analyzers.Test.CSharp9/OrderingRules/SA1202CSharp9UnitTests.cs

@@ -3,9 +3,65 @@
 
 namespace StyleCop.Analyzers.Test.CSharp9.OrderingRules
 {
+    using System.Threading;
+    using System.Threading.Tasks;
+    using Microsoft.CodeAnalysis.Testing;
     using StyleCop.Analyzers.Test.CSharp8.OrderingRules;
+    using Xunit;
+    using static StyleCop.Analyzers.Test.Verifiers.StyleCopCodeFixVerifier<
+        StyleCop.Analyzers.OrderingRules.SA1202ElementsMustBeOrderedByAccess,
+        StyleCop.Analyzers.OrderingRules.ElementOrderCodeFixProvider>;
 
     public partial class SA1202CSharp9UnitTests : SA1202CSharp8UnitTests
     {
+        [Fact]
+        [WorkItem(3971, "https://github.com/DotNetAnalyzers/StyleCopAnalyzers/issues/3971")]
+        public async Task TestPartialMethodExplicitAccessibilityDeclarationOrderingAsync()
+        {
+            var testCode = @"
+public partial class TestClass
+{
+    private void Helper() { }
+
+    public partial void {|#0:TestMethod|}();
+}
+
+public partial class TestClass
+{
+    public partial void TestMethod()
+    {
+    }
+}
+";
+
+            var expected = Diagnostic().WithLocation(0).WithArguments("public", "private");
+
+            await VerifyCSharpDiagnosticAsync(testCode, expected, CancellationToken.None).ConfigureAwait(false);
+        }
+
+        [Fact]
+        [WorkItem(3971, "https://github.com/DotNetAnalyzers/StyleCopAnalyzers/issues/3971")]
+        public async Task TestPartialMethodExplicitAccessibilityImplementationOrderingAsync()
+        {
+            var testCode = @"
+public partial class TestClass
+{
+    public partial void TestMethod();
+}
+
+public partial class TestClass
+{
+    private void Helper() { }
+
+    public partial void {|#0:TestMethod|}()
+    {
+    }
+}
+";
+
+            var expected = Diagnostic().WithLocation(0).WithArguments("public", "private");
+
+            await VerifyCSharpDiagnosticAsync(testCode, expected, CancellationToken.None).ConfigureAwait(false);
+        }
     }
 }

StyleCop.Analyzers/StyleCop.Analyzers.Test/OrderingRules/SA1202UnitTests.cs

@@ -989,5 +989,23 @@ public string
 
             await VerifyCSharpDiagnosticAsync(testCode, expected, CancellationToken.None).ConfigureAwait(false);
         }
+
+        [Fact]
+        [WorkItem(3971, "https://github.com/DotNetAnalyzers/StyleCopAnalyzers/issues/3971")]
+        public async Task TestPartialMethodImplicitPrivateOrderingAsync()
+        {
+            var testCode = @"
+public partial class TestClass
+{
+    partial void TestMethod();
+
+    public void {|#0:PublicMethod|}() { }
+}
+";
+
+            var expected = Diagnostic().WithLocation(0).WithArguments("public", "private");
+
+            await VerifyCSharpDiagnosticAsync(testCode, expected, CancellationToken.None).ConfigureAwait(false);
+        }
     }
 }