test: fix tests, stop using make_napari_viewer fixture

src/napari_micromanager/_gui_objects/_stages_widget.py

@@ -1,3 +1,4 @@
+from contextlib import suppress
 from typing import Optional, cast
 
 from pymmcore_plus import CMMCorePlus, DeviceType
@@ -52,8 +53,9 @@
         for i in reversed(range(self.layout().count())):
             if item := self.layout().takeAt(i):
                 if wdg := item.widget():
-                    wdg.setParent(QWidget())
-                    wdg.deleteLater()
+                    with suppress(RuntimeError):
+                        wdg.setParent(QWidget())
+                        wdg.deleteLater()
 
     def dragEnterEvent(self, event: QDragEnterEvent) -> None:
         event.accept()

tests/conftest.py

@@ -1,16 +1,24 @@
+from __future__ import annotations
+
 import itertools
+from contextlib import suppress
 from pathlib import Path
+from typing import TYPE_CHECKING, Any
 
+import napari
 import pytest
 import useq
 from napari_micromanager._util import NMM_METADATA_KEY
 from napari_micromanager.main_window import MainWindow
 from pymmcore_plus import CMMCorePlus
 
+if TYPE_CHECKING:
+    from collections.abc import Iterator
+
 
 # to create a new CMMCorePlus() for every test
 @pytest.fixture
-def core(monkeypatch):
+def core(monkeypatch: pytest.MonkeyPatch) -> CMMCorePlus:
     new_core = CMMCorePlus()
     config_path = str(Path(__file__).parent / "test_config.cfg")
     new_core.loadSystemConfiguration(config_path)
@@ -19,9 +27,16 @@ def core(monkeypatch):
 
 
 @pytest.fixture
-def main_window(core: CMMCorePlus, make_napari_viewer):
-    viewer = make_napari_viewer()
-    win = MainWindow(viewer=viewer)
+def napari_viewer(qapp: Any) -> Iterator[napari.Viewer]:
+    viewer = napari.Viewer(show=False)
+    yield viewer
+    with suppress(RuntimeError):
+        viewer.close()
+
+
+@pytest.fixture
+def main_window(core: CMMCorePlus, napari_viewer: napari.Viewer) -> MainWindow:
+    win = MainWindow(viewer=napari_viewer)
     assert core == win._mmc
     return win
 
@@ -50,7 +65,9 @@ def mda_sequence(request: pytest.FixtureRequest) -> useq.MDASequence:
 
 
 @pytest.fixture(params=[True, False], ids=["splitC", "no_splitC"])
-def mda_sequence_splits(mda_sequence: useq.MDASequence, request) -> useq.MDASequence:
+def mda_sequence_splits(
+    mda_sequence: useq.MDASequence, request: pytest.FixtureRequest
+) -> useq.MDASequence:
     if request.param:
         meta = {"split_channels": True}
         mda_sequence.metadata[NMM_METADATA_KEY] = meta

tests/test_layer_scale.py

@@ -6,21 +6,21 @@
 from napari_micromanager._mda_handler import _NapariMDAHandler
 
 if TYPE_CHECKING:
+    import napari
     from napari_micromanager.main_window import MainWindow
     from pymmcore_plus import CMMCorePlus
     from useq import MDASequence
 
 
 @pytest.mark.parametrize("axis_order", ["tpcz", "tpzc"])
 def test_layer_scale(
-    make_napari_viewer,
+    napari_viewer: napari.Viewer,
     mda_sequence_splits: MDASequence,
     axis_order: str,
     core: CMMCorePlus,
 ) -> None:
-    viewer = make_napari_viewer()
     mmc = core
-    handler = _NapariMDAHandler(mmc, viewer)
+    handler = _NapariMDAHandler(mmc, napari_viewer)
 
     mmc.setProperty("Objective", "Label", "Nikon 20X Plan Fluor ELWD")
 
@@ -30,7 +30,7 @@ def test_layer_scale(
     # create zarr layer
     handler._on_mda_started(sequence)
 
-    layer = viewer.layers[0]
+    layer = napari_viewer.layers[0]
     if sequence.z_plan:
         num_z = len(list(sequence.z_plan))
         assert layer.scale[layer.data.shape.index(num_z)] == z_step