Fix struct handling in makepy generated code

CHANGES.txt

@@ -15,6 +15,7 @@ Coming in build 311, as yet unreleased
 --------------------------------------
 * Fixed a regression that broke special __dunder__ methods with CoClass. (#1870, #2493, @Avasam, @geppi)
 * Fixed dispatch handling for properties (@the-snork)
+* Fixed struct handling in makepy generated code (@the-snork)
 
 Build 310, released 2025/03/16
 ------------------------------

com/TestSources/PyCOMTest/PyCOMImpl.cpp

@@ -619,6 +619,16 @@ HRESULT CPyCOMTest::GetStruct(TestStruct1 *ret)
     return S_OK;
 }
 
+HRESULT CPyCOMTest::GetOutStruct(TestStruct1 *ret)
+{
+    if (ret == NULL) {
+        return E_POINTER;
+    }
+    ret->int_value = 99;
+    ret->str_value = SysAllocString(L"Hello from C++");
+    return S_OK;
+}
+
 HRESULT CPyCOMTest::ModifyStruct(TestStruct1 *prec)
 {
     prec->int_value = 100;

com/TestSources/PyCOMTest/PyCOMImpl.h

@@ -98,6 +98,7 @@ class CPyCOMTest : public IDispatchImpl<IPyCOMTest, &IID_IPyCOMTest, &LIBID_PyCO
     STDMETHOD(TestOptionals2)(double dval, BSTR strval, short sval, SAFEARRAY **pRet);
     STDMETHOD(TestOptionals3)(double dval, short sval, IPyCOMTest **outinterface2);
     STDMETHOD(GetStruct)(TestStruct1 *ret);
+    STDMETHOD(GetOutStruct)(TestStruct1 *ret);
     STDMETHOD(DoubleString)(BSTR inStr, BSTR *outStr);
     STDMETHOD(DoubleInOutString)(BSTR *str);
     STDMETHOD(TestMyInterface)(IUnknown *t);

com/TestSources/PyCOMTest/PyCOMTest.idl

@@ -26,7 +26,7 @@ typedef enum // Missing EnumTestAttributes2
 	uuid(6bcdcb60-5605-11d0-ae5f-cadd4c000000),
 	version(1.1),
 	// an extended character in the help string should stress things...
-	helpstring("Python COM Test Harness 1.0 Type Library, © pywin32 contributors")
+	helpstring("Python COM Test Harness 1.0 Type Library, © pywin32 contributors")
 ]
 library PyCOMTestLib
 {
@@ -70,7 +70,7 @@ library PyCOMTestLib
 		const long LongTest2 = 0x7FFFFFFFL;
 		const unsigned char UCharTest = 255;
 		const char CharTest = -1;
-		const LPWSTR StringTest = L"Hello Wo®ld";
+		const LPWSTR StringTest = L"Hello Wo®ld";
 	};
 
 	enum TestAttributes3{ // Note missing the enum name.
@@ -260,7 +260,8 @@ library PyCOMTestLib
 							   [in, defaultvalue(1)] short sval,
 							   [out, retval] IPyCOMTest **ppout );
 		HRESULT GetStruct([out, retval]TestStruct1 *ret);
-		HRESULT DoubleString([in] BSTR inStr, [out, retval] BSTR *outStr);
+        HRESULT GetOutStruct([out] TestStruct1 *ret);
+        HRESULT DoubleString([in] BSTR inStr, [out, retval] BSTR * outStr);
 		HRESULT DoubleInOutString([in,out] BSTR *str);
 		[restricted] HRESULT NotScriptable([in,out] int *val);
 

com/win32com/client/build.py

@@ -382,6 +382,22 @@ def MakeDispatchFuncMethod(self, entry, name, bMakeClass=1):
         if doc and doc[1]:
             ret.append(linePrefix + "\t" + _makeDocString(doc[1]))
 
+        for i in range(len(fdesc[2])):
+            desc = fdesc[2][i]
+
+            if (
+                desc[1] & (pythoncom.PARAMFLAG_FOUT | pythoncom.PARAMFLAG_FIN)
+                == pythoncom.PARAMFLAG_FOUT
+            ):
+                if (
+                    desc[0] & pythoncom.VT_RECORD
+                    and desc[3]
+                    and desc[3].__class__.__name__ == "PyIID"
+                ):
+                    newVal = f"pythoncom.GetRecordFromGuids(CLSID, MajorVersion, MinorVersion, LCID, {repr(desc[3])})"
+                    ret.append(linePrefix + "\t" + f"if {names[i+1]} == {defOutArg}:")
+                    ret.append(linePrefix + "\t\t" + f"{names[i+1]} = {newVal}")
+
         resclsid = entry.GetResultCLSID()
         if resclsid:
             resclsid = "'%s'" % resclsid
@@ -592,7 +608,7 @@ def _ResolveType(typerepr, itypeinfo):
                 return pythoncom.VT_UNKNOWN, clsid, retdoc
 
             elif typeKind == pythoncom.TKIND_RECORD:
-                return pythoncom.VT_RECORD, None, None
+                return pythoncom.VT_RECORD, resultAttr.iid, None
             raise NotSupportedException("Can not resolve alias or user-defined type")
     return typeSubstMap.get(typerepr, typerepr), None, None
 
@@ -612,6 +628,7 @@ def _BuildArgList(fdesc, names):
     name_num = 0
     while len(names) < numArgs:
         names.append("arg%d" % (len(names),))
+
     # As per BuildCallList(), avoid huge lines.
     # Hack a "\n" at the end of every 5th name
     for i in range(0, len(names), 5):

com/win32com/client/genpy.py

@@ -1153,6 +1153,17 @@ def do_generate(self):
         print("}", file=stream)
         print(file=stream)
 
+        # create classes for records
+        for record in recordItems.values():
+            if record.clsid != pythoncom.IID_NULL:
+                print(f"class {record.doc[0]}:", file=stream)
+                print("\tdef __new__(cls, *args, **kwargs):", file=stream)
+                print(
+                    f"\t\treturn pythoncom.GetRecordFromGuids(CLSID, MajorVersion, MinorVersion, LCID, '{record.clsid}')",
+                    file=stream,
+                )
+        print(file=stream)
+
         # Write out _all_ my generated CLSID's in the map
         if self.generate_type == GEN_FULL:
             print("CLSIDToClassMap = {", file=stream)

com/win32com/client/makepy.py

@@ -319,6 +319,8 @@ def GenerateFromTypeLibSpec(
                 outputName = full_name + ".py"
             fileUse = gen.open_writer(outputName)
             progress.LogBeginGenerate(outputName)
+        elif isinstance(file, str):
+            fileUse = gen.open_writer(file)
         else:
             fileUse = file
 
@@ -330,6 +332,8 @@ def GenerateFromTypeLibSpec(
             if file is None:
                 with gencache.ModuleMutex(this_name):
                     gen.finish_writer(outputName, fileUse, worked)
+            elif isinstance(file, str):
+                gen.finish_writer(file, fileUse, worked)
         importlib.invalidate_caches()
         if bToGenDir:
             progress.SetDescription("Importing module")

com/win32com/test/testPyComTest.py

@@ -6,6 +6,7 @@
 sys.coinit_flags = 0  # Must be free-threaded!
 import datetime
 import decimal
+import importlib
 import os
 import time
 
@@ -22,7 +23,9 @@
     DispatchBaseClass,
     Record,
     constants,
+    makepy,
     register_record_class,
+    selecttlb,
 )
 
 importMsg = "**** PyCOMTest is not installed ***\n  PyCOMTest is a Python test specific COM client and server.\n  It is likely this server is not installed on this machine\n  To install the server, you must get the win32com sources\n  and build it using MS Visual C++"
@@ -866,6 +869,34 @@ def TestQueryInterface(long_lived_server=0, iterations=5):
         tester.TestQueryInterface()
 
 
+def TestMakePy():
+    tlb = [
+        entry
+        for entry in selecttlb.EnumTlbs()
+        if entry.clsid.lower() == "{6bcdcb60-5605-11d0-ae5f-cadd4c000000}"
+    ]
+    if len(tlb) == 0:
+        return
+
+    file_name = "makepy_generated.py"
+
+    makepy.GenerateFromTypeLibSpec(tlb[0].dll, file_name)
+
+    spec = importlib.util.spec_from_file_location("makepy_generated", file_name)
+    module = importlib.util.module_from_spec(spec)
+    sys.modules["makepy_generated"] = module
+    spec.loader.exec_module(module)
+
+    coclass = module.CoPyCOMTest()
+
+    # test structs
+    coclass.GetStruct()
+    coclass.GetOutStruct()
+
+    data = module.TestStruct1()
+    coclass.ModifyStruct(data)
+
+
 class Tester(win32com.test.util.TestCase):
     def testVTableInProc(self):
         # We used to crash running this the second time - do it a few times
@@ -903,6 +934,9 @@ def testDynamic(self):
     def testGenerated(self):
         TestGenerated()
 
+    def testMakePy(self):
+        TestMakePy()
+
 
 if __name__ == "__main__":
     # XXX - todo - Complete hack to crank threading support.