TST: Add test [circle full]

doc/conf.py

@@ -27,7 +27,7 @@
 import mne
 from mne.viz import Brain
 from mne.utils import (linkcode_resolve, # noqa, analysis:ignore
-                       _get_referrers, sizeof_fmt)
+                       _assert_no_instances, sizeof_fmt)
 
 if LooseVersion(sphinx_gallery.__version__) < LooseVersion('0.2'):
     raise ImportError('Must have at least version 0.2 of sphinx-gallery, got '
@@ -460,12 +460,9 @@ def __call__(self, gallery_conf, fname):
         # turn it off here (otherwise the build can be very slow)
         plt.ioff()
         plt.rcParams['animation.embed_limit'] = 30.
-        new = '\n'
-        n, ref = _get_referrers(Brain)  # calls gc.collect()
-        assert n == 0, f'Brain after:\n{new.join(ref)}'
+        _assert_no_instances(Brain, 'running')  # calls gc.collect()
         if Plotter is not None:
-            n, ref = _get_referrers(Plotter)  # calls gc.collect()
-            assert n == 0, f'Plotter after:\n{new.join(ref)}'
+            _assert_no_instances(Plotter, 'running')
         # This will overwrite some Sphinx printing but it's useful
         # for memory timestamps
         if os.getenv('SG_STAMP_STARTS', '').lower() == 'true':

mne/conftest.py

@@ -28,7 +28,7 @@
 import numpy as np
 import mne
 from mne.datasets import testing
-from mne.utils import _pl, _get_referrers
+from mne.utils import _pl, _assert_no_instances
 
 test_path = testing.data_path(download=False)
 s_path = op.join(test_path, 'MEG', 'sample')
@@ -472,15 +472,36 @@ def download_is_error(monkeypatch):
 
 
 @pytest.fixture()
-def brain_gc():
+def brain_gc(request):
     """Ensure that brain can be properly garbage collected."""
+    keys = ('renderer_interactive', 'renderer')
+    assert set(request.fixturenames) & set(keys) != set()
+    for key in keys:
+        if key in request.fixturenames:
+            is_pv = request.getfixturevalue(key)._get_3d_backend() == 'pyvista'
+            break
+    if not is_pv:
+        yield
+        return
     from mne.viz import Brain
-    new = '\n'
-    n, ref = _get_referrers(Brain)
-    assert n == 0, f'{n} before:\n{new.join(ref)}'
+    _assert_no_instances(Brain, 'before')
+    ignore = set(id(o) for o in gc.get_objects())
     yield
-    n, ref = _get_referrers(Brain)
-    assert n == 0, f'{n} after:\n{new.join(ref)}'
+    _assert_no_instances(Brain, 'after')
+    # We only check VTK for PyVista -- Mayavi/PySurfer is not as strict
+    objs = gc.get_objects()
+    bad = list()
+    for o in objs:
+        try:
+            name = o.__class__.__name__
+        except Exception:  # old Python, probably
+            pass
+        else:
+            if name.startswith('vtk') and id(o) not in ignore:
+                bad.append(name)
+        del o
+    del objs, ignore, Brain
+    assert len(bad) == 0, 'VTK objects linger:\n' + '\n'.join(bad)
 
 
 def pytest_sessionfinish(session, exitstatus):

mne/utils/__init__.py

@@ -32,7 +32,8 @@
                        ClosingStringIO)
 from .misc import (run_subprocess, _pl, _clean_names, pformat, _file_like,
                    _explain_exception, _get_argvalues, sizeof_fmt,
-                   running_subprocess, _DefaultEventParser, _get_referrers)
+                   running_subprocess, _DefaultEventParser,
+                   _assert_no_instances)
 from .progressbar import ProgressBar
 from ._testing import (run_tests_if_main, run_command_if_main,
                        requires_sklearn,

mne/utils/misc.py

@@ -322,15 +322,26 @@ def _file_like(obj):
     return all(callable(getattr(obj, name, None)) for name in ('read', 'seek'))
 
 
-def _get_referrers(cls):
+def _assert_no_instances(cls, when=''):
+    __tracebackhide__ = True
     n = 0
     ref = list()
-    new = '\n'
     gc.collect()
-    for obj in gc.get_objects():
+    objs = gc.get_objects()
+    for obj in objs:
         if isinstance(obj, cls):
-            n += 1
-            ref.extend([
-                f'{r.__class__.__name__}: {repr(r)[:100].replace(new, " ")}'
-                for r in gc.get_referrers(obj)])
-    return n, ref
+            rr = gc.get_referrers(obj)
+            count = 0
+            for r in rr:
+                if r is not objs and \
+                        r is not globals() and \
+                        r is not locals() and \
+                        not inspect.isframe(r):
+                    ref.append(
+                        f'{r.__class__.__name__}: ' +
+                        repr(r)[:100].replace('\n', ' '))
+                    count += 1
+                del r
+            del rr
+            n += count > 0
+    assert n == 0, f'{n} {when}:\n' + '\n'.join(ref)

mne/viz/_brain/_brain.py

@@ -267,6 +267,12 @@ def __init__(self, subject_id, hemi, surf, title=None,
                                        bgcolor=background,
                                        shape=shape,
                                        fig=figure)
+
+        if _get_3d_backend() == "pyvista":
+            self.plotter = self._renderer.plotter
+            self.window = self.plotter.app_window
+            self.window.signal_close.connect(self._clean)
+
         for h in self._hemis:
             # Initialize a Surface object as the geometry
             geo = Surface(subject_id, h, surf, subjects_dir, offset,
@@ -303,6 +309,7 @@ def __init__(self, subject_id, hemi, surf, title=None,
                         actor, mesh = mesh_data.actor, mesh_data
                     self._hemi_meshes[h] = mesh
                     self._hemi_actors[h] = actor
+                    del mesh_data, actor, mesh
                 else:
                     self._renderer.polydata(
                         self._hemi_meshes[h],
@@ -375,14 +382,11 @@ def setup_time_viewer(self, time_viewer=True, show_traces=True):
         self.slider_tube_color = (0.69803922, 0.70196078, 0.70980392)
 
         # Direct access parameters:
-        self.plotter = self._renderer.plotter
         self._iren = self._renderer.plotter.iren
         self.main_menu = self.plotter.main_menu
-        self.window = self.plotter.app_window
         self.tool_bar = self.window.addToolBar("toolbar")
         self.status_bar = self.window.statusBar()
         self.interactor = self.plotter.interactor
-        self.window.signal_close.connect(self._clean)
 
         # Derived parameters:
         self.playback_speed = self.default_playback_speed_value
@@ -426,16 +430,29 @@ def setup_time_viewer(self, time_viewer=True, show_traces=True):
     def _clean(self):
         # resolve the reference cycle
         self.clear_points()
+        for h in self._hemis:
+            actor = self._hemi_actors[h]
+            if actor is not None:
+                mapper = actor.GetMapper()
+                mapper.SetLookupTable(None)
+                actor.SetMapper(None)
         self._clear_callbacks()
-        self.actions.clear()
-        self.sliders.clear()
-        if self.mpl_canvas is not None:
+        if getattr(self, 'mpl_canvas', None) is not None:
             self.mpl_canvas.clear()
-        for key in list(self.act_data_smooth.keys()):
-            self.act_data_smooth[key] = None
+        if getattr(self, 'act_data_smooth', None) is not None:
+            for key in list(self.act_data_smooth.keys()):
+                self.act_data_smooth[key] = None
+        # XXX this should be done in PyVista
+        for renderer in self.plotter.renderers:
+            renderer.RemoveAllLights()
+        for key in ('lighting', 'interactor', 'app_window', '_RenderWindow',
+                    '_Iren'):
+            setattr(self.plotter, key, None)
+        # XXX end PyVista
         for key in ('reps', 'plotter', 'main_menu', 'window', 'tool_bar',
                     'status_bar', 'interactor', 'mpl_canvas', 'time_actor',
-                    'picked_renderer', 'act_data_smooth', '_iren'):
+                    'picked_renderer', 'act_data_smooth', '_iren',
+                    'actions', 'sliders', 'geo', '_hemi_actors', '_data'):
             setattr(self, key, None)
 
     @contextlib.contextmanager
@@ -1206,6 +1223,8 @@ def remove_point(self, mesh):
 
     def clear_points(self):
         """Clear the picked points."""
+        if not hasattr(self, '_spheres'):
+            return
         for sphere in list(self._spheres):  # will remove itself, so copy
             self.remove_point(sphere)
         assert sum(len(v) for v in self.picked_points.values()) == 0
@@ -1307,6 +1326,8 @@ def help(self):
 
     def _clear_callbacks(self):
         from ..backends._pyvista import _remove_picking_callback
+        if not hasattr(self, 'callbacks'):
+            return
         for callback in self.callbacks.values():
             if callback is not None:
                 if hasattr(callback, "plotter"):

mne/viz/_brain/tests/test_brain.py

@@ -92,6 +92,13 @@ def GetPosition(self):
         return np.array(self.GetPickPosition()) - (0, 0, 100)
 
 
+@testing.requires_testing_data
+def test_brain_gc(renderer, brain_gc):
+    """Test that a minimal version of Brain gets GC'ed."""
+    brain = Brain('fsaverage', 'both', 'inflated', subjects_dir=subjects_dir)
+    brain.close()
+
+
 @testing.requires_testing_data
 def test_brain_init(renderer, tmpdir, pixel_ratio, brain_gc):
     """Test initialization of the Brain instance."""