piker/tests/ui/conftest.py

253 lines
8.2 KiB
Python

from collections.abc import Iterator
from pathlib import Path
import shutil
from types import SimpleNamespace
from PyQt6.QtCore import (
QCoreApplication,
QEvent,
QSettings,
)
from PyQt6.QtWidgets import (
QApplication,
QWidget,
)
import pyqtgraph as pg
from pyqtgraph import ViewBox
import pytest
from pytestqt.qtbot import QtBot
from piker import config
_PREEXISTING_SETTING: str = 'pytest/preexisting'
_OWNED_SETTING: str = 'pytest/owned'
@pytest.fixture(scope='session', autouse=True)
def ui_process_sentinel(
isolated_xdg_config_home: Path,
) -> Iterator[Path]:
'''
Keep known process-owned state across all UI tests.
'''
# TODO: expose public config-dir get/set APIs like
# `modden.config.dirs.get_conf_dir()` and `set_conf_dir()` so
# tests do not reach into Piker's import-cached path globals.
config_dir: Path = config._click_config_dir
config_dir.mkdir(parents=True, exist_ok=True)
sentinel_path: Path = config_dir / 'pytest-preexisting'
sentinel_existed: bool = sentinel_path.exists()
sentinel_bytes: bytes|None = None
if sentinel_existed:
sentinel_bytes = sentinel_path.read_bytes()
sentinel_path.write_text('keep-me', encoding='utf-8')
settings: QSettings = QSettings('pikers', 'piker')
settings.setFallbacksEnabled(False)
setting_existed: bool = settings.contains(
_PREEXISTING_SETTING,
)
setting_value: object = settings.value(
_PREEXISTING_SETTING,
)
settings.setValue(_PREEXISTING_SETTING, 'keep-me')
settings.sync()
try:
assert config_dir.is_relative_to(isolated_xdg_config_home)
yield sentinel_path
finally:
if setting_existed:
settings.setValue(
_PREEXISTING_SETTING,
setting_value,
)
else:
settings.remove(_PREEXISTING_SETTING)
settings.sync()
if sentinel_existed:
assert sentinel_bytes is not None
sentinel_path.write_bytes(sentinel_bytes)
else:
sentinel_path.unlink(missing_ok=True)
@pytest.fixture(autouse=True)
def isolated_ui_state(
qapp: QApplication,
qtbot: QtBot,
tmp_path: Path,
isolated_xdg_config_home: Path,
ui_process_sentinel: Path,
) -> Iterator[SimpleNamespace]:
'''
Restore mutable process state after one real Qt test.
Pytest-qt owns the shared `QApplication` and closes widgets
before this fixture unwinds. This guard snapshots the remaining
process globals, removes exact test-owned config, and reports any
widget or PyQtGraph object that survived normal pytest-qt
cleanup.
'''
top_levels: set[QWidget] = set(
qapp.topLevelWidgets()
)
all_views: set[ViewBox] = set(ViewBox.AllViews)
named_views: dict[str, ViewBox] = dict(ViewBox.NamedViews)
pg_options: dict[str, object] = dict(pg.CONFIG_OPTIONS)
quit_on_last_window: bool = (
qapp.quitOnLastWindowClosed()
)
config_paths: dict[str, Path] = {
'_click_config_dir': config._click_config_dir,
'_config_dir': config._config_dir,
'_watchlists_data_path': config._watchlists_data_path,
}
settings: QSettings = QSettings('pikers', 'piker')
settings.setFallbacksEnabled(False)
settings_state: dict[str, object] = {
key: settings.value(key)
for key in settings.allKeys()
}
test_config_dir: Path = tmp_path / 'piker-config'
test_config_dir.mkdir()
state: SimpleNamespace = SimpleNamespace(
qapp=qapp,
process_config_home=isolated_xdg_config_home,
preexisting_config=ui_process_sentinel,
test_config_dir=test_config_dir,
preexisting_setting=_PREEXISTING_SETTING,
owned_setting=_OWNED_SETTING,
)
try:
yield state
finally:
# Collect every isolation failure so cleanup of one process
# global cannot prevent restoration of the remaining globals.
errors: list[Exception] = []
# Pytest-qt closes registered widgets before fixture
# teardown, but Qt completes `QWidget.deleteLater()`
# asynchronously.
QCoreApplication.sendPostedEvents(
None,
QEvent.Type.DeferredDelete,
)
qapp.processEvents()
# Any addition to `QApplication.topLevelWidgets()` after the
# deferred-delete drain is a widget pytest-qt failed to own.
leaked_widgets: set[QWidget] = (
set(qapp.topLevelWidgets()) - top_levels
)
for widget in leaked_widgets:
widget.close()
widget.deleteLater()
QCoreApplication.sendPostedEvents(
None,
QEvent.Type.DeferredDelete,
)
qapp.processEvents()
if leaked_widgets:
errors.append(AssertionError(
'pytest-qt left test-owned top-level widgets alive: '
f'{leaked_widgets!r}'
))
# `ViewBox.AllViews` and `ViewBox.NamedViews` are
# process-wide weak registries used for linked-axis
# discovery.
# Close leaked views, report either registry delta, then
# restore the exact baseline so a failure cannot contaminate
# the next test.
leaked_views: set[ViewBox] = (
set(ViewBox.AllViews) - all_views
)
for view in leaked_views:
view.close()
if leaked_views:
errors.append(AssertionError(
'test-owned `ViewBox.AllViews` entries survived: '
f'{leaked_views!r}'
))
named_views_changed: bool = (
dict(ViewBox.NamedViews) != named_views
)
if named_views_changed:
errors.append(AssertionError(
'test mutated `ViewBox.NamedViews` without cleanup'
))
ViewBox.AllViews.clear()
ViewBox.AllViews.update({
view: None
for view in all_views
})
ViewBox.NamedViews.clear()
ViewBox.NamedViews.update(named_views)
ViewBox.updateAllViewLists()
# PyQtGraph options and Qt's last-window policy are mutable
# process globals, not properties owned by one test widget.
pg.CONFIG_OPTIONS.clear()
pg.CONFIG_OPTIONS.update(pg_options)
qapp.setQuitOnLastWindowClosed(quit_on_last_window)
# Rebuild this test application's `QSettings` keys exactly:
# test-owned keys disappear while pre-existing values
# survive.
for key in settings.allKeys():
settings.remove(key)
for key, value in settings_state.items():
settings.setValue(key, value)
settings.sync()
# Restore Piker's import-cached path globals before deleting
# the function-owned config tree to prevent a dangling path.
for name, path in config_paths.items():
setattr(config, name, path)
shutil.rmtree(test_config_dir, ignore_errors=True)
# Re-read every restored process value instead of trusting
# the cleanup assignments; each mismatch joins one report.
if dict(pg.CONFIG_OPTIONS) != pg_options:
errors.append(AssertionError(
'`pyqtgraph.CONFIG_OPTIONS` was not restored'
))
if qapp.quitOnLastWindowClosed() != quit_on_last_window:
errors.append(AssertionError(
'`QApplication.quitOnLastWindowClosed()` changed'
))
if {
name: getattr(config, name)
for name in config_paths
} != config_paths:
errors.append(AssertionError(
'Piker config path globals were not restored'
))
if {
key: settings.value(key)
for key in settings.allKeys()
} != settings_state:
errors.append(AssertionError(
'`QSettings` keys were not restored exactly'
))
if test_config_dir.exists():
errors.append(AssertionError(
'test-owned config directory survived teardown'
))
# Raise only after all restoration and verification
# completes, preserving each leak signal for diagnosis.
if errors:
raise ExceptionGroup(
'UI isolation teardown failed',
errors,
)