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Statically type OInfo. (#13973)...
Statically type OInfo. (#13973) In view of working with #13860, some cleanup inspect to be properly typed, and using stricter datastructure. Instead of dict we now use dataclasses, this will make sure that fields type and access can be stricter and verified not only at runtime, but by mypy

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qt.py
86 lines | 3.2 KiB | text/x-python | PythonLexer
import sys
import os
from IPython.external.qt_for_kernel import QtCore, QtGui, enum_helper
from IPython import get_ipython
# If we create a QApplication, keep a reference to it so that it doesn't get
# garbage collected.
_appref = None
_already_warned = False
def _exec(obj):
# exec on PyQt6, exec_ elsewhere.
obj.exec() if hasattr(obj, "exec") else obj.exec_()
def _reclaim_excepthook():
shell = get_ipython()
if shell is not None:
sys.excepthook = shell.excepthook
def inputhook(context):
global _appref
app = QtCore.QCoreApplication.instance()
if not app:
if sys.platform == 'linux':
if not os.environ.get('DISPLAY') \
and not os.environ.get('WAYLAND_DISPLAY'):
import warnings
global _already_warned
if not _already_warned:
_already_warned = True
warnings.warn(
'The DISPLAY or WAYLAND_DISPLAY environment variable is '
'not set or empty and Qt5 requires this environment '
'variable. Deactivate Qt5 code.'
)
return
try:
QtCore.QApplication.setAttribute(QtCore.Qt.AA_EnableHighDpiScaling)
except AttributeError: # Only for Qt>=5.6, <6.
pass
try:
QtCore.QApplication.setHighDpiScaleFactorRoundingPolicy(
QtCore.Qt.HighDpiScaleFactorRoundingPolicy.PassThrough
)
except AttributeError: # Only for Qt>=5.14.
pass
_appref = app = QtGui.QApplication([" "])
# "reclaim" IPython sys.excepthook after event loop starts
# without this, it defaults back to BaseIPythonApplication.excepthook
# and exceptions in the Qt event loop are rendered without traceback
# formatting and look like "bug in IPython".
QtCore.QTimer.singleShot(0, _reclaim_excepthook)
event_loop = QtCore.QEventLoop(app)
if sys.platform == 'win32':
# The QSocketNotifier method doesn't appear to work on Windows.
# Use polling instead.
timer = QtCore.QTimer()
timer.timeout.connect(event_loop.quit)
while not context.input_is_ready():
# NOTE: run the event loop, and after 50 ms, call `quit` to exit it.
timer.start(50) # 50 ms
_exec(event_loop)
timer.stop()
else:
# On POSIX platforms, we can use a file descriptor to quit the event
# loop when there is input ready to read.
notifier = QtCore.QSocketNotifier(
context.fileno(), enum_helper("QtCore.QSocketNotifier.Type").Read
)
try:
# connect the callback we care about before we turn it on
# lambda is necessary as PyQT inspect the function signature to know
# what arguments to pass to. See https://github.com/ipython/ipython/pull/12355
notifier.activated.connect(lambda: event_loop.exit())
notifier.setEnabled(True)
# only start the event loop we are not already flipped
if not context.input_is_ready():
_exec(event_loop)
finally:
notifier.setEnabled(False)