def queue(self):
QueuingContext.append(self, owns=tuple(self.obs))
for o in self.obs:
try:
QueuingContext.update_info(o, owner=self)
except AttributeError:
pass
return self
def __enter__(self):
if not QueuingContext.recording():
# if the tape is the first active queuing context
# monkeypatch the operations to support the new queuing context
with contextlib.ExitStack() as stack:
for mock in mock_operations():
stack.enter_context(mock)
self._stack = stack.pop_all()
QueuingContext.append(self)
return super().__enter__()
def __enter__(self):
QuantumTape._lock.acquire()
try:
if not QueuingContext.recording():
# if the tape is the first active queuing context
# monkeypatch the operations to support the new queuing context
with contextlib.ExitStack() as stack:
for mock in mock_operations():
stack.enter_context(mock)
self._stack = stack.pop_all()
QueuingContext.append(self)
return super().__enter__()
except Exception as _:
QuantumTape._lock.release()
raise
def test_append_no_context(self):
"""Test that append does not fail when no context is present."""
QueuingContext.append(qml.PauliZ(0))