Adding support for specifying a transparent struct kind

Author: tannergooding

sources/ClangSharp.PInvokeGenerator/PInvokeGenerator.VisitDecl.cs

@@ -1589,10 +1589,12 @@ void OutputVtblHelperMethod(CXXRecordDecl cxxRecordDecl, CXXMethodDecl cxxMethod
                 var remappedName = FixupNameForMultipleHits(cxxMethodDecl);
                 var name = GetRemappedCursorName(cxxMethodDecl);
                 var needsReturnFixup = false;
+                var needsCastToTransparentStruct = false;
 
                 if (returnType.Kind != CXTypeKind.CXType_Void)
                 {
                     needsReturnFixup = NeedsReturnFixup(cxxMethodDecl);
+                    needsCastToTransparentStruct = _config.WithTransparentStructs.TryGetValue(returnTypeName, out var transparentStruct) && IsTransparentStructHandle(transparentStruct.Kind);
                 }
 
                 var desc = new FunctionOrDelegateDesc<(string Name, PInvokeGenerator This)>
@@ -1652,6 +1654,13 @@ void OutputVtblHelperMethod(CXXRecordDecl cxxRecordDecl, CXXMethodDecl cxxMethod
                     body.Write("return ");
                 }
 
+                if (needsCastToTransparentStruct)
+                {
+                    body.Write("((");
+                    body.Write(returnTypeName);
+                    body.Write(")(");
+                }
+
                 if (needsReturnFixup)
                 {
                     body.Write('*');
@@ -1748,6 +1757,11 @@ void OutputVtblHelperMethod(CXXRecordDecl cxxRecordDecl, CXXMethodDecl cxxMethod
                     body.Write(" != 0");
                 }
 
+                if (needsCastToTransparentStruct)
+                {
+                    body.Write("))");
+                }
+
                 body.WriteSemicolon();
                 body.WriteNewline();
 
@@ -2743,9 +2757,9 @@ private void VisitVarDecl(VarDecl varDecl)
                     {
                         flags |= ValueFlags.Copy;
                     }
-                    else if (_config.WithTransparentStructs.TryGetValue(typeName, out var transparentValueTypeName))
+                    else if (_config.WithTransparentStructs.TryGetValue(typeName, out var transparentStruct))
                     {
-                        typeName = transparentValueTypeName;
+                        typeName = transparentStruct.Name;
                     }
                 }
                 else if ((varDecl.StorageClass == CX_StorageClass.CX_SC_Static) || openedOutputBuilder)

sources/ClangSharp.PInvokeGenerator/PInvokeGenerator.VisitStmt.cs

@@ -702,9 +702,9 @@ private void VisitExplicitCastExpr(ExplicitCastExpr explicitCastExpr)
             {
                 var cursorName = GetCursorName(varDecl);
 
-                if (cursorName.StartsWith("ClangSharpMacro_") && _config.WithTransparentStructs.TryGetValue(typeName, out var transparentValueTypeName))
+                if (cursorName.StartsWith("ClangSharpMacro_") && _config.WithTransparentStructs.TryGetValue(typeName, out var transparentStruct))
                 {
-                    typeName = transparentValueTypeName;
+                    typeName = transparentStruct.Name;
                 }
             }