# Import vispy.gloo first when on Windows otherwise there are strange
# side-effects when PyQt4.Qt is imported first (which it now is in QtPy)
import os
import sys
if sys.platform.startswith('win'):
import vispy.gloo.gl # noqa
from glue.utils.qt import get_qapp # noqa
try:
import objgraph
except ImportError:
OBJGRAPH_INSTALLED = False
else:
OBJGRAPH_INSTALLED = True
# The application has to always be referenced to avoid being shut down, so we
# keep a reference to it here
app = None
def pytest_configure(config):
os.environ['GLUE_TESTING'] = 'True'
global app
app = get_qapp()
def pytest_unconfigure(config):
os.environ.pop('GLUE_TESTING')
global app
app = None
VIEWER_CLASSES = ['VispyScatterViewer', 'VispyIsosurfaceViewer', 'VispyVolumeViewer']
def pytest_runtest_setup(item):
if OBJGRAPH_INSTALLED:
app.processEvents()
for viewer_cls in VIEWER_CLASSES:
obj = objgraph.by_type(viewer_cls)
item._viewer_count = len(obj)
def pytest_runtest_teardown(item, nextitem):
# The following is a check to make sure that once the viewer and
# application have been closed, there are no leftover references to data
# viewers or application. This was introduced because there were
# previously circular references that meant that viewer instances were
# not properly garbage collected, which in turn meant they still reacted
# in some cases to events.
if OBJGRAPH_INSTALLED and hasattr(item, '_viewer_count'):
app.processEvents()
for viewer_cls in VIEWER_CLASSES:
obj = objgraph.by_type(viewer_cls)
if len(obj) > item._viewer_count:
objgraph.show_backrefs(objgraph.by_type(viewer_cls))
raise ValueError("No net viewers should be created in tests")
