TST: Test that a channel specific annot is plotted at the correct ypos

mne_qt_browser/tests/test_pg_specific.py

@@ -84,19 +84,32 @@ def test_annotations_interactions(raw_orig, pg_backend):
     fig.msg_box.close()
 
 
-def test_ch_specific_annot(raw_orig):
+def test_ch_specific_annot(raw_orig, pg_backend):
     """Test plotting channel specific annotations."""
     from mne import Annotations
     from pyqtgraph.graphicsItems.FillBetweenItem import FillBetweenItem
 
     ch_names = ["MEG 0133", "MEG 0142", "MEG 0143", "MEG 0423"]
     annots = Annotations([1], [2], "some_chs", ch_names=[ch_names])
     raw_orig.set_annotations(annots)
+
     fig = raw_orig.plot()
+    fig_ch_names = list(fig.mne.ch_names[fig.mne.ch_order])
     fig.test_mode = True
+
     # one item for each channel in a channel specific annot
-    rects = [item for item in fig.mne.plt.items if isinstance(item, FillBetweenItem)]
-    assert len(rects) == 4
+    fill_betweens = [
+        item for item in fig.mne.plt.items if isinstance(item, FillBetweenItem)]
+    assert len(fill_betweens) == 4  # 4 channels in annots[0].ch_names
+
+    # check that a channel specific annot is plotted at the correct ypos
+    last_fill_between = fill_betweens[-1].curves[0]
+    # "MEG 0423" should be the 28th channel in the plot.
+    # the +1 is needed because ypos indexing of the traces starts at 1, not 0
+    want_index = fig_ch_names.index(raw_orig.annotations.ch_names[0][-1]) + 1
+    # The round basically just rounds 27.5 up to 28
+    got_index = np.round(last_fill_between.yData[0],).astype(int)
+    assert got_index == want_index  # should be 28
     fig.close()