1 files changed, 189 insertions, 0 deletions
diff --git a/sources/pyside6/tests/pysidetest/multiple_inheritance_test.py b/sources/pyside6/tests/pysidetest/multiple_inheritance_test.py
new file mode 100644
index 000000000..49550ba55
--- /dev/null
+++ b/sources/pyside6/tests/pysidetest/multiple_inheritance_test.py
@@ -0,0 +1,189 @@
+# Copyright (C) 2023 The Qt Company Ltd.
+# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+import os
+import sys
+import unittest
+
+from pathlib import Path
+sys.path.append(os.fspath(Path(__file__).resolve().parents[1]))
+from init_paths import init_test_paths
+init_test_paths(False)
+
+from helper.usesqapplication import UsesQApplication
+from PySide6 import QtCore, QtGui, QtWidgets
+from PySide6.QtWidgets import QMainWindow, QLabel, QWidget
+
+
+def xprint(*args, **kw):
+    if "-v" in sys.argv:
+        print(*args, **kw)
+
+
+# This is the original testcase of PYSIDE-1564
+class Age(object):
+    def __init__(self, age=0, **kwds):
+        super().__init__(**kwds)
+
+        self.age = age
+
+
+class Person(QtCore.QObject, Age):
+    def __init__(self, name, **kwds):
+        super().__init__(**kwds)
+
+        self.name = name
+
+
+class OriginalMultipleInheritanceTest(unittest.TestCase):
+
+    def testIt(self):
+        xprint()
+        p = Person("Joe", age=38)
+        xprint(f"p.age = {p.age}")
+        # This would crash if MI does not work.
+
+# More tests follow:
+
+
+# mro ('C', 'A', 'QObject', 'Object', 'B', 'object')
+class A(QtCore.QObject):
+    def __init__(self, anna=77, **kw):
+        xprint(f'A: before init kw = {kw}')
+        super().__init__(**kw)
+        xprint('A: after init')
+
+
+class B:
+    def __init__(self, otto=6, age=7, **kw):
+        xprint(f'B: before init kw = {kw}')
+        if "killme" in kw:
+            raise AssertionError("asdf")
+        super().__init__(**kw)
+        self.age = age
+        xprint('B: after init')
+
+
+class C(A, B):
+    def __init__(self, **kw):
+        xprint(f'C: before init kw = {kw}')
+        super().__init__(**kw)
+        xprint('C: after init')
+
+
+# mro ('F', 'D', 'QCursor', 'E', 'QLabel', 'QFrame', 'QWidget', 'QObject',
+#      'QPaintDevice', 'Object', 'object')
+class D(QtGui.QCursor):
+    def __init__(self, anna=77, **kw):
+        xprint(f'D: before init kw = {kw}')
+        super().__init__(**kw)
+        xprint('D: after init')
+
+
+class E:
+    def __init__(self, age=7, **kw):
+        xprint(f'E: before init kw = {kw}')
+        super().__init__(**kw)
+        self.age = age
+        xprint('E: after init')
+
+
+class F(D, E, QtWidgets.QLabel):
+    def __init__(self, **kw):
+        xprint(f'F: before init kw = {kw}')
+        super().__init__(**kw)
+        xprint('F: after init')
+
+
+# mro ('I', 'G', 'QTextDocument', 'H', 'QLabel', 'QFrame', 'QWidget', 'QObject',
+#      'QPaintDevice', 'Object', 'object')
+# Similar, but this time we want to reach `H` without support from `super`.
+class G(QtGui.QTextDocument):
+    pass
+
+
+class H:
+    def __init__(self, age=7, **kw):
+        xprint(f'H: before init kw = {kw}')
+        super().__init__(**kw)
+        self.age = age
+        xprint('H: after init')
+
+
+class II(G, H, QtWidgets.QLabel):
+    pass
+
+
+# PYSIDE-2294: Friedemann's test adapted.
+#              We need to ignore positional args in mixin classes.
+class Ui_X_MainWindow(object):  # Emulating uic
+    def setupUi(self, MainWindow):
+        MainWindow.resize(400, 300)
+        self.lbl = QLabel(self)
+
+
+class MainWindow(QMainWindow, Ui_X_MainWindow):
+    def __init__(self, parent=None):
+        super().__init__(parent)
+        self.setupUi(self)
+
+
+class AdditionalMultipleInheritanceTest(UsesQApplication):
+
+    def testABC(self):
+        xprint()
+        res = C(otto=3, anna=5)
+        self.assertEqual(res.age, 7)
+        xprint()
+        with self.assertRaises(AssertionError):
+            res = C(killme=42)
+        xprint()
+
+    def testDEF(self):
+        xprint()
+        res = F(anna=5)
+        self.assertEqual(res.age, 7)
+        xprint()
+
+    def testGHI(self):
+        xprint()
+        res = II(age=7)
+        self.assertEqual(res.age, 7)
+        xprint()
+
+    def testParentDoesNotCrash(self):
+        # This crashed with
+        # TypeError: object.__init__() takes exactly one argument (the instance to initialize)
+        MainWindow()
+
+
+# PYSIDE-2654: Additional missing init test.
+#              This must work if no __init__ is defined (Ui_Form)
+class Ui_Form(object):
+    pass
+
+
+class Mixin:
+    def __init__(self, **kwargs) -> None:
+        super().__init__(**kwargs)
+
+
+class Card(Mixin, QWidget):
+    def __init__(self, parent=None) -> None:
+        super().__init__(parent=parent)
+
+
+class Demo(Card, Ui_Form):
+    def __init__(self) -> None:
+        super().__init__()
+
+
+class MissingInitFunctionTest(UsesQApplication):
+    def testMissing(self):
+        Demo()
+        # Tests if this works. Would crash without the extra
+        # check for object.__init__
+
+
+if __name__ == "__main__":
+    unittest.main()