Reworked operator overloading support.

src/Generator/Generators/CLI/CLIHeadersTemplate.cs

@@ -1,8 +1,8 @@
 using System;
 using System.Collections.Generic;
-using System.IO;
 using System.Linq;
 using CppSharp.AST;
+using CppSharp.Generators.CSharp;
 using CppSharp.Types;
 
 namespace CppSharp.Generators.CLI
@@ -512,7 +512,10 @@ namespace CppSharp.Generators.CLI
             if (method.IsVirtual || method.IsOverride)
                 Write("virtual ");
 
-            if (method.IsStatic)
+            var isBuiltinOperator = method.IsOperator &&
+                Operators.IsBuiltinOperator(method.OperatorKind);
+
+            if (method.IsStatic || isBuiltinOperator)
                 Write("static ");
 
             if (method.Kind == CXXMethodKind.Constructor || method.Kind == CXXMethodKind.Destructor)

src/Generator/Generators/CLI/CLIMarshal.cs

@@ -524,7 +524,11 @@ namespace CppSharp.Generators.CLI
 
             Context.Return.Write(marshalVar);
 
-            if (Context.Parameter.Type.IsPointer())
+            var param = Context.Parameter;
+            if (param.Kind == ParameterKind.OperatorParameter)
+                return;
+
+            if (param.Type.IsPointer())
                 ArgumentPrefix.Write("&");
         }
 

src/Generator/Generators/CLI/CLISourcesTemplate.cs

@@ -743,29 +743,36 @@ namespace CppSharp.Generators.CLI
                 Write("auto {0}{1} = ",(function.ReturnType.Type.IsReference())? "&": string.Empty,
                     Generator.GeneratedIdentifier("ret"));
 
-            if (!IsNativeFunctionOrStaticMethod(function))
+            if (function.IsOperator)
             {
-                if (isValueType)
-                {
-                    Write("{0}.", valueMarshalName);
+                var kind = function.OperatorKind;
+
+                var isBinary = function.Parameters.Count > 0;
+                var opName = function.Name.Replace("operator", "").Trim();
+
+                // Binary operator
+                if (isBinary)
+                    WriteLine("{0} {1} {2};", @params[0].Name, opName,
+                        @params[1].Name);
             }
-                else if (IsNativeMethod(function))
+            else
             {
-                    Write("((::{0}*)NativePtr)->", @class.QualifiedOriginalName);
-                }
-            }
-
                 if (IsNativeFunctionOrStaticMethod(function))
                 {
                     Write("::{0}(", function.QualifiedOriginalName);
                 }
                 else
                 {
+                    if (isValueType)
+                        Write("{0}.", valueMarshalName);
+                    else if (IsNativeMethod(function))
+                        Write("((::{0}*)NativePtr)->", @class.QualifiedOriginalName);
                     Write("{0}(", function.OriginalName);
                 }
 
                 GenerateFunctionParams(@params);
                 WriteLine(");");
+            }
 
             foreach(var paramInfo in @params)
             {
@@ -830,6 +837,9 @@ namespace CppSharp.Generators.CLI
             if (method == null) 
                 return true;
 
+            if (method.IsOperator && Operators.IsBuiltinOperator(method.OperatorKind))
+                return true;
+
             return method.IsStatic || method.Conversion != MethodConversionKind.None;
         }
 

src/Generator/Generators/CSharp/CSharpTextTemplate.cs

@@ -1595,9 +1595,11 @@ namespace CppSharp.Generators.CSharp
             var needsFixedThis = needsInstance && isValueType;
             var @params = GenerateFunctionParamsMarshal(parameters, function);
 
-            if (function.HasIndirectReturnTypeParameter)
+            var originalFunction = function.OriginalFunction ?? function;
+
+            if (originalFunction.HasIndirectReturnTypeParameter)
             {
-                var hiddenParam = function.Parameters[0];
+                var hiddenParam = originalFunction.Parameters[0];
                 if (hiddenParam.Kind != ParameterKind.IndirectReturnType)
                     throw new NotSupportedException("Expected hidden structure parameter kind");
 
@@ -1618,7 +1620,7 @@ namespace CppSharp.Generators.CSharp
                 names.Add(name);
             }
 
-            if (function.HasIndirectReturnTypeParameter)
+            if (originalFunction.HasIndirectReturnTypeParameter)
             {
                 var name = string.Format("new IntPtr(&{0})", GeneratedIdentifier("ret"));
                 names.Insert(0, name);
@@ -1638,7 +1640,7 @@ namespace CppSharp.Generators.CSharp
                 WriteLine("var {0} = ToInternal();", Generator.GeneratedIdentifier("instance"));
             }
 
-            if (needsReturn && !function.HasIndirectReturnTypeParameter)
+            if (needsReturn && !originalFunction.HasIndirectReturnTypeParameter)
                 Write("var {0} = ", GeneratedIdentifier("ret"));
 
             WriteLine("{0}({1});", functionName, string.Join(", ", names));

tests/Basic/Basic.Tests.cs

@@ -28,7 +28,7 @@ public class BasicTests
         Assert.That(retFoo.A, Is.EqualTo(7));
         Assert.That(retFoo.B, Is.EqualTo(2.0));
 
-        var foo2 = new Foo2 {A = 4, B = 2, C = 3};
+        var foo2 = new Foo2 { A = 4, B = 2, C = 3 };
         Assert.That(hello.AddFoo(foo2), Is.EqualTo(6));
         Assert.That(hello.AddFoo2(foo2), Is.EqualTo(9));
 
@@ -43,10 +43,14 @@ public class BasicTests
         Assert.That(hello.RetEnum(Enum.F), Is.EqualTo(-9));
     }
 
-    static void Main(string[] args)
+    [Test]
+    public void TestFunctionOperator()
     {
-        var hello = new Hello();
-        hello.RetFoo(7, 2.0f);
+        var bar = new Bar { A = 4, B = 7 };
+        var bar1 = new Bar { A = 5, B = 10 };
+        var barSum = bar + bar1;
+        Assert.That(barSum.A, Is.EqualTo(bar.A + bar1.A));
+        Assert.That(barSum.B, Is.EqualTo(bar.B + bar1.B));
     }
 }
  

tests/Basic/Basic.cpp

@@ -75,3 +75,11 @@ int unsafeFunction(const Bar& ret)
 {
     return ret.A;
 }
+
+Bar operator+(const Bar& b1, const Bar& b2)
+{
+    Bar b;
+    b.A = b1.A + b2.A;
+    b.B = b1.B + b2.B;
+    return b;
+}

tests/Basic/Basic.h

@@ -71,4 +71,6 @@ public:
     int RetEnum(Enum);
 };
 
+DLL_API Bar operator+(const Bar &, const Bar &);
+
 int DLL_API unsafeFunction(const Bar& ret);