ensure that all widgets are created on the same thread

testbed/tests/widgets/conftest.py

@@ -84,18 +84,21 @@ def verify_vertical_alignment():
 
 
 def build_cleanup_test(
- widget_class, args=None, kwargs=None, skip_platforms=(), xfail_platforms=()
+ widget_constructor, args=None, kwargs=None, skip_platforms=(), xfail_platforms=()
 ):
  async def test_cleanup():
  nonlocal args, kwargs
 
  skip_on_platforms(*skip_platforms)
  xfail_on_platforms(*xfail_platforms, reason="Leaks memory")
 
- widget = widget_class(
- *(args if args is not None else ()),
- **(kwargs if kwargs is not None else {}),
- )
+ if args is None:
+ args = ()
+
+ if kwargs is None:
+ kwargs = {}
+
+ widget = widget_constructor(*args, **kwargs)
  ref = weakref.ref(widget)
 
  # Args or kwargs may hold a backref to the widget itself, for example if they

testbed/tests/widgets/test_box.py

@@ -18,4 +18,6 @@ async def widget():
  return toga.Box(style=Pack(width=100, height=200))
 
 
-test_cleanup = build_cleanup_test(toga.Box, xfail_platforms=("iOS",))
+test_cleanup = build_cleanup_test(
+ toga.Box, kwargs={"argument": "test"}, xfail_platforms=("iOS",)
+)

testbed/tests/widgets/test_optioncontainer.py

@@ -73,8 +73,9 @@ async def widget(content1, content2, content3, on_select_handler):
 
 
 test_cleanup = build_cleanup_test(
- toga.OptionContainer,
- kwargs={"content": [("Tab 1", toga.Box())]},
+ # Pass a function here to prevent init of toga.Box() in a different thread than
+ # toga.OptionContainer. This would raise a runtime error on Windows.
+ lambda: toga.OptionContainer(content=[("Tab 1", toga.Box())]),
  xfail_platforms=("android", "iOS", "linux"),
 )
 

testbed/tests/widgets/test_scrollcontainer.py

@@ -74,8 +74,9 @@ async def widget(content, on_scroll):
 
 
 test_cleanup = build_cleanup_test(
- toga.ScrollContainer,
- kwargs={"content": toga.Box()},
+ # Pass a function here to prevent init of toga.Box() in a different thread than
+ # toga.ScrollContainer. This would raise a runtime error on Windows.
+ lambda: toga.ScrollContainer(content=toga.Box()),
  xfail_platforms=("android", "iOS", "linux"),
 )
 

testbed/tests/widgets/test_splitcontainer.py

@@ -62,8 +62,9 @@ async def widget(content1, content2):
 
 
 test_cleanup = build_cleanup_test(
- toga.SplitContainer,
- kwargs={"content": [toga.Box(), toga.Box()]},
+ # Pass a function here to prevent init of toga.Box() in a different thread than
+ # toga.SplitContainer. This would raise a runtime error on Windows.
+ lambda: toga.SplitContainer(content=[toga.Box(), toga.Box()]),
  skip_platforms=("android", "iOS"),
 )