Explcitly check dimensions in slice tests

src/napari_matplotlib/tests/conftest.py

@@ -1,7 +1,9 @@
 import os
 from pathlib import Path
+from typing import Any, Dict, Tuple
 
 import numpy as np
+import numpy.typing as npt
 import pytest
 from skimage import data
 
@@ -18,7 +20,7 @@ def image_data(request):
 
 
 @pytest.fixture
-def astronaut_data():
+def astronaut_data() -> Tuple[npt.NDArray[Any], Dict[Any, Any]]:
     return data.astronaut(), {"rgb": True}
 
 

src/napari_matplotlib/tests/test_slice.py

@@ -9,7 +9,11 @@
 def test_slice_3D(make_napari_viewer, brain_data):
     viewer = make_napari_viewer()
     viewer.theme = "light"
+
+    data = brain_data[0]
+    assert data.ndim == 3
     viewer.add_image(brain_data[0], **brain_data[1])
+
     axis = viewer.dims.last_used
     slice_no = brain_data[0].shape[0] - 1
     viewer.dims.set_current_step(axis, slice_no)
@@ -23,7 +27,11 @@ def test_slice_3D(make_napari_viewer, brain_data):
 def test_slice_2D(make_napari_viewer, astronaut_data):
     viewer = make_napari_viewer()
     viewer.theme = "light"
+
+    data = astronaut_data[0]
+    assert data.ndim == 2
     viewer.add_image(astronaut_data[0], **astronaut_data[1])
+
     fig = SliceWidget(viewer).figure
     # Need to return a copy, as original figure is too eagerley garbage
     # collected by the widget