From 73670debbc4f4bcee1ce0414685e5b46163ac6be Mon Sep 17 00:00:00 2001
From: josetr <37419832+josetr@users.noreply.github.com>
Date: Fri, 16 Oct 2020 20:18:32 +0100
Subject: [PATCH] Fix anonymous member name colliding with enclosing type name
 (#1425)

* Fix anonymous member name colliding with enclosing type name
---
 src/Generator/Passes/CleanInvalidDeclNamesPass.cs |  9 ++++++++-
 tests/CSharp/CSharp.Tests.cs                      |  6 ++++++
 tests/CSharp/CSharp.h                             |  4 ++++
 tests/CSharp/ExcludedUnit.hpp                     | 11 +++++++++++
 4 files changed, 29 insertions(+), 1 deletion(-)
 create mode 100644 tests/CSharp/ExcludedUnit.hpp

diff --git a/src/Generator/Passes/CleanInvalidDeclNamesPass.cs b/src/Generator/Passes/CleanInvalidDeclNamesPass.cs
index 00d71959..56113d60 100644
--- a/src/Generator/Passes/CleanInvalidDeclNamesPass.cs
+++ b/src/Generator/Passes/CleanInvalidDeclNamesPass.cs
@@ -146,7 +146,14 @@ namespace CppSharp.Passes
         {
             var anonymousDecls = decls.Where(p => string.IsNullOrEmpty(p.Name)).ToList();
             for (int i = 0; i < anonymousDecls.Count; i++)
-                anonymousDecls[i].Name = $"_{i}";
+            {
+                var anonymousDecl = anonymousDecls[i];
+
+                if (anonymousDecl.Namespace != null && anonymousDecl.Namespace.Name == anonymousDecl.Name)
+                    anonymousDecl.Name = $"__{i}";
+                else
+                    anonymousDecl.Name = $"_{i}";
+            }
         }
     }
 }
diff --git a/tests/CSharp/CSharp.Tests.cs b/tests/CSharp/CSharp.Tests.cs
index d7d7662d..2dd953ef 100644
--- a/tests/CSharp/CSharp.Tests.cs
+++ b/tests/CSharp/CSharp.Tests.cs
@@ -1429,4 +1429,10 @@ public unsafe class CSharpTests : GeneratorTestFixture
     {
         Assert.That(CSharp.CSharp.TakeTypemapTypedefParam(false), Is.False);
     }
+
+    [Test]
+    public void TestAnonymousMemberNameCollision()
+    {
+        StringAssert.EndsWith(nameof(CSharp.TestAnonymousMemberNameCollision._0.__0), "__0");
+    }
 }
diff --git a/tests/CSharp/CSharp.h b/tests/CSharp/CSharp.h
index 277f5afa..e181dde5 100644
--- a/tests/CSharp/CSharp.h
+++ b/tests/CSharp/CSharp.h
@@ -6,6 +6,7 @@
 #include <limits>
 #include <string>
 #include "AnotherUnit.h"
+#include "ExcludedUnit.hpp"
 #include "CSharpTemplates.h"
 
 class DLL_API Foo
@@ -1401,3 +1402,6 @@ struct {
 typedef int boolean_t;
 DLL_API boolean_t takeTypemapTypedefParam(boolean_t b);
 
+class DLL_API TestAnonymousMemberNameCollision : public ClassUsingUnion {
+
+};
diff --git a/tests/CSharp/ExcludedUnit.hpp b/tests/CSharp/ExcludedUnit.hpp
new file mode 100644
index 00000000..4a7b38d8
--- /dev/null
+++ b/tests/CSharp/ExcludedUnit.hpp
@@ -0,0 +1,11 @@
+#pragma once
+
+class ClassUsingUnion {
+public:
+	union {
+		float arr[2];
+		struct {
+			float a, b;
+		};
+	};
+};