import functools
from pytestqt.qt_compat import qt_api
class _AbstractSignalBlocker(object):
"""
Base class for :class:`SignalBlocker` and :class:`MultiSignalBlocker`.
Provides :meth:`wait` and a context manager protocol, but no means to add
new signals and to detect when the signals should be considered "done".
This needs to be implemented by subclasses.
Subclasses also need to provide ``self._signals`` which should evaluate to
``False`` if no signals were configured.
"""
def __init__(self, timeout=1000, raising=True):
self._loop = qt_api.QtCore.QEventLoop()
self.timeout = timeout
self.signal_triggered = False
self.raising = raising
if timeout is None:
self._timer = None
else:
self._timer = qt_api.QtCore.QTimer(self._loop)
self._timer.setSingleShot(True)
self._timer.setInterval(timeout)
def wait(self):
"""
Waits until either a connected signal is triggered or timeout is reached.
:raise ValueError: if no signals are connected and timeout is None; in
this case it would wait forever.
"""
__tracebackhide__ = True
if self.signal_triggered:
return
if self.timeout is None and not self._signals:
raise ValueError("No signals or timeout specified.")
if self._timer is not None:
self._timer.timeout.connect(self._quit_loop_by_timeout)
self._timer.start()
self._loop.exec_()
if not self.signal_triggered and self.raising:
raise SignalTimeoutError("Didn't get signal after %sms." %
self.timeout)
def _quit_loop_by_timeout(self):
try:
self._cleanup()
finally:
self._loop.quit()
def _cleanup(self):
if self._timer is not None:
_silent_disconnect(self._timer.timeout, self._quit_loop_by_timeout)
self._timer.stop()
self._timer = None
def __enter__(self):
return self
def __exit__(self, type, value, traceback):
__tracebackhide__ = True
if value is None:
# only wait if no exception happened inside the "with" block
self.wait()
[docs]class SignalBlocker(_AbstractSignalBlocker):
"""
Returned by :meth:`pytestqt.qtbot.QtBot.waitSignal` method.
:ivar int timeout: maximum time to wait for a signal to be triggered. Can
be changed before :meth:`wait` is called.
:ivar bool signal_triggered: set to ``True`` if a signal (or all signals in
case of :class:`MultipleSignalBlocker`) was triggered, or
``False`` if timeout was reached instead. Until :meth:`wait` is called,
this is set to ``None``.
:ivar bool raising:
If :class:`SignalTimeoutError` should be raised if a timeout occurred.
.. note:: contrary to the parameter of same name in
:meth:`pytestqt.qtbot.QtBot.waitSignal`, this parameter does not
consider the :ref:`qt_wait_signal_raising`.
:ivar list args:
The arguments which were emitted by the signal, or None if the signal
wasn't emitted at all.
.. versionadded:: 1.10
The *args* attribute.
.. automethod:: wait
.. automethod:: connect
"""
def __init__(self, timeout=1000, raising=True, check_params_cb=None):
super(SignalBlocker, self).__init__(timeout, raising=raising)
self._signals = []
self.args = None
self.check_params_callback = check_params_cb
[docs] def connect(self, signal):
"""
Connects to the given signal, making :meth:`wait()` return once
this signal is emitted.
More than one signal can be connected, in which case **any** one of
them will make ``wait()`` return.
:param signal: QtCore.Signal
"""
signal.connect(self._quit_loop_by_signal)
self._signals.append(signal)
def _quit_loop_by_signal(self, *args):
"""
quits the event loop and marks that we finished because of a signal.
"""
if self.check_params_callback:
if not self.check_params_callback(*args):
return # parameter check did not pass
try:
self.signal_triggered = True
self.args = list(args)
self._cleanup()
finally:
self._loop.quit()
def _cleanup(self):
super(SignalBlocker, self)._cleanup()
for signal in self._signals:
_silent_disconnect(signal, self._quit_loop_by_signal)
self._signals = []
[docs]class MultiSignalBlocker(_AbstractSignalBlocker):
"""
Returned by :meth:`pytestqt.qtbot.QtBot.waitSignals` method, blocks until
all signals connected to it are triggered or the timeout is reached.
Variables identical to :class:`SignalBlocker`:
- ``timeout``
- ``signal_triggered``
- ``raising``
.. automethod:: wait
"""
def __init__(self, timeout=1000, raising=True, check_params_cbs=None, order="none"):
super(MultiSignalBlocker, self).__init__(timeout, raising=raising)
self.order = order
self.check_params_callbacks = check_params_cbs
self._signals_emitted = [] # list of booleans, indicates whether the signal was already emitted
self._signals_map = {} # maps from a unique Signal to a list of indices where to expect signal instance emits
self._signals = [] # list of all Signals (for compatibility with _AbstractSignalBlocker)
self._slots = [] # list of slot functions
self._signal_expected_index = 0 # only used when forcing order
self._strict_order_violated = False
def add_signals(self, signals):
"""
Adds the given signal to the list of signals which :meth:`wait()` waits
for.
:param list signals: list of QtCore.Signal`s
"""
# determine uniqueness of signals, creating a map that maps from a unique signal to a list of indices
# (positions) where this signal is expected (in case order matters)
signals_as_str = [str(signal) for signal in signals]
signal_str_to_signal = {} # maps from a signal-string to one of the signal instances (the first one found)
for index, signal_str in enumerate(signals_as_str):
signal = signals[index]
if signal_str not in signal_str_to_signal:
signal_str_to_signal[signal_str] = signal
self._signals_map[signal] = [index] # create a new list
else:
# append to existing list
first_signal_that_occurred = signal_str_to_signal[signal_str]
self._signals_map[first_signal_that_occurred].append(index)
for signal in signals:
self._signals_emitted.append(False)
for unique_signal in self._signals_map:
slot = functools.partial(self._signal_emitted, unique_signal)
self._slots.append(slot)
unique_signal.connect(slot)
self._signals.append(unique_signal)
def _signal_emitted(self, signal, *args):
"""
Called when a given signal is emitted.
If all expected signals have been emitted, quits the event loop and
marks that we finished because signals.
"""
if self.order == "none":
# perform the test for every matching index (stop after the first one that matches)
successfully_emitted = False
successful_index = -1
potential_indices = self._get_unemitted_signal_indices(signal)
for potential_index in potential_indices:
if self._check_callback(potential_index, *args):
successful_index = potential_index
successfully_emitted = True
break
if successfully_emitted:
self._signals_emitted[successful_index] = True
elif self.order == "simple":
potential_indices = self._get_unemitted_signal_indices(signal)
if potential_indices:
if self._signal_expected_index == potential_indices[0]:
if self._check_callback(self._signal_expected_index, *args):
self._signals_emitted[self._signal_expected_index] = True
self._signal_expected_index += 1
else: # self.order == "strict"
if not self._strict_order_violated:
# only do the check if the strict order has not been violated yet
self._strict_order_violated = True # assume the order has been violated this time
potential_indices = self._get_unemitted_signal_indices(signal)
if potential_indices:
if self._signal_expected_index == potential_indices[0]:
if self._check_callback(self._signal_expected_index, *args):
self._signals_emitted[self._signal_expected_index] = True
self._signal_expected_index += 1
self._strict_order_violated = False # order has not been violated after all!
if not self._strict_order_violated and all(self._signals_emitted):
try:
self.signal_triggered = True
self._cleanup()
finally:
self._loop.quit()
def _check_callback(self, index, *args):
"""
Checks if there's a callback that evaluates the validity of the parameters. Returns False if there is one
and its evaluation revealed that the parameters were invalid. Returns True otherwise.
"""
if self.check_params_callbacks:
callback_func = self.check_params_callbacks[index]
if callback_func:
if not callback_func(*args):
return False
return True
def _get_unemitted_signal_indices(self, signal):
"""Returns the indices for the provided signal for which NO signal instance has been emitted yet."""
return [index for index in self._signals_map[signal] if self._signals_emitted[index] == False]
def _cleanup(self):
super(MultiSignalBlocker, self)._cleanup()
for i in range(len(self._signals)):
signal = self._signals[i]
slot = self._slots[i]
_silent_disconnect(signal, slot)
del self._signals_emitted[:]
self._signals_map.clear()
del self._slots[:]
class SignalEmittedSpy(object):
"""
.. versionadded:: 1.11
An object which checks if a given signal has ever been emitted.
Intended to be used as a context manager.
"""
def __init__(self, signal):
self.signal = signal
self.emitted = False
self.args = None
def slot(self, *args):
self.emitted = True
self.args = args
def __enter__(self):
self.signal.connect(self.slot)
def __exit__(self, type, value, traceback):
self.signal.disconnect(self.slot)
def assert_not_emitted(self):
if self.emitted:
if self.args:
raise SignalEmittedError("Signal %r unexpectedly emitted with "
"arguments %r" %
(self.signal, list(self.args)))
else:
raise SignalEmittedError("Signal %r unexpectedly emitted" %
(self.signal,))
[docs]class SignalTimeoutError(Exception):
"""
.. versionadded:: 1.4
The exception thrown by :meth:`pytestqt.qtbot.QtBot.waitSignal` if the
*raising* parameter has been given and there was a timeout.
"""
pass
class SignalEmittedError(Exception):
"""
.. versionadded:: 1.11
The exception thrown by :meth:`pytestqt.qtbot.QtBot.assertNotEmitted` if a
signal was emitted unexpectedly.
"""
pass
def _silent_disconnect(signal, slot):
"""Disconnects a signal from a slot, ignoring errors. Sometimes
Qt might disconnect a signal automatically for unknown reasons.
"""
try:
signal.disconnect(slot)
except (TypeError, RuntimeError): # pragma: no cover
pass