Generate valid C# when a renamed override causes conflicts

Signed-off-by: Dimitar Dobrev <dpldobrev@protonmail.com>

Author: ddobrev

src/Generator/Passes/RenamePass.cs

@@ -199,9 +199,9 @@ where typedefDecl.Type.Desugar() is FunctionType
                     declarations.AddRange(@class.TemplateParameters);
             }
 
-            var result = declarations.Any(d => d != decl && d.Name == newName);
-            if (result)
-                return true;
+            var existing = declarations.Find(d => d != decl && d.Name == newName);
+            if (existing != null)
+                return CheckExisting(decl, existing);
 
             if (decl is Method && decl.IsGenerated)
                 return @class.GetPropertyByName(newName) != null;
@@ -226,6 +226,18 @@ private static IEnumerable<Function> GetFunctionsWithTheSameParams(Function func
                 f => !f.Ignore && f.Parameters.SequenceEqual(function.Parameters, new ParameterComparer()));
         }
 
+        private static bool CheckExisting(Declaration decl, Declaration existing)
+        {
+            var method = decl as Method;
+            var property = decl as Property;
+            if (method?.IsOverride != true && property?.IsOverride != true)
+                return true;
+
+            existing.Name = existing.Name == existing.OriginalName ?
+                existing.Name + "_" : existing.OriginalName;
+            return false;
+        }
+
         public override bool VisitClassDecl(Class @class)
         {
             if (!base.VisitClassDecl(@class))

tests/CSharp/CSharp.Tests.cs

@@ -61,7 +61,11 @@ public void TestUncompilableCode()
             hasOverride.CauseRenamingError();
         using (var qux = new Qux())
         {
-            new Bar(qux).Dispose();
+            qux.Type.GetHashCode();
+            using (Bar bar = new Bar(qux))
+            {
+                bar.Type.GetHashCode();
+            }
         }
         using (var quux = new Quux())
         {

tests/CSharp/CSharp.cpp

@@ -230,6 +230,11 @@ int Qux::takeReferenceToPointer(Foo*& ret)
     return ret->A;
 }
 
+int Qux::type() const
+{
+    return 0;
+}
+
 Bar::Bar(Qux qux)
 {
 }
@@ -286,6 +291,11 @@ void Bar::setIndex(int value)
     index = value;
 }
 
+int Bar::type() const
+{
+    return 1;
+}
+
 ForceCreationOfInterface::ForceCreationOfInterface()
 {
 }

tests/CSharp/CSharp.h

@@ -85,6 +85,7 @@ class DLL_API Qux
     void setInterface(Qux* qux);
     virtual void makeClassDynamic();
     virtual int takeReferenceToPointer(Foo*& ret);
+    virtual int type() const;
 };
 
 class DLL_API Bar : public Qux
@@ -115,6 +116,8 @@ class DLL_API Bar : public Qux
         int publicInt;
         double publicDouble;
     };
+    static const int Type = 4;
+    int type() const override;
 
 protected:
     enum class ProtectedNestedEnum