Update traceback and win32com error support to native unicode

Author: mhammond

CHANGES.txt

@@ -6,6 +6,13 @@ However contributors are encouraged to add their own entries for their work.
 
 Note that build 228 was the last version supporting Python 2.
 
+Since build 303:
+----------------
+* Fixed codepage/mojibake issues when non-ascii characters were included in
+  COM exceptions raised by Python apps. This should be invisible, but might
+  break any workarounds which were used, such as using specific encodings in
+  these strings. (#1823, #1833)
+
 Since build 302:
 ----------------
 * Tweaks to how DLLs are loaded and our installation found, which should

Pythonwin/win32uimodule.cpp

@@ -503,13 +503,13 @@ BOOL DisplayPythonTraceback(PyObject *exc_type, PyObject *exc_val, PyObject *exc
             SetWindowText(title);
             GetDlgItem(IDCANCEL)->ShowWindow(SW_HIDE);
             GetDlgItem(IDOK)->SetWindowText(_T("Close"));
-            char *msg = GetPythonTraceback(m_exc_type, m_exc_value, m_exc_tb);
-            char *msg_free = msg;
+            WCHAR *msg = GetPythonTraceback(m_exc_type, m_exc_value, m_exc_tb);
+            WCHAR *msg_free = msg;
             // Translate '\n' to '\r\n' - do it the easy way!
             CString useMsg;
             for (; *msg; msg++)
-                if (*msg == '\n')
-                    useMsg += "\r\n";
+                if (*msg == L'\n')
+                    useMsg += L"\r\n";
                 else
                     useMsg += *msg;
             free(msg_free);
@@ -659,7 +659,7 @@ void DefaultExceptionHandler(int action, const TCHAR *context, const TCHAR *extr
         }
         else
             PyErr_Restore(type, value, traceback);
-        fprintf(stderr, "%s\n", context);
+        fwprintf(stderr, L"%s\n", context);
         // Now print it.
         PyErr_Print();
     }

com/win32com/makegw/makegwenum.py

@@ -267,7 +267,7 @@ def _write_enumgw_cpp(f, interface):
   error:
 	PyErr_Clear();	// just in case
 	Py_DECREF(result);
-	return PyCom_SetCOMErrorFromSimple(E_FAIL, IID_IEnum%(enumtype)s, "Next() did not return a sequence of objects");
+	return PyCom_HandleIEnumNoSequence(IID_IEnum%(enumtype)s);
 }
 
 STDMETHODIMP PyGEnum%(enumtype)s::Skip( 
@@ -324,7 +324,7 @@ def _write_enumgw_cpp(f, interface):
 	/* done with the result; this DECREF is also for <punk> */
 	Py_DECREF(result);
 
-	return PyCom_SetCOMErrorFromSimple(hr, IID_IEnum%(enumtype)s, "Python could not convert the result from Next() into the required COM interface");
+	return PyCom_CheckIEnumNextResult(hr, IID_IEnum%(enumtype)s);
 }
 """
         % locals()