Source code for ophyd_async.core._mock_signal_utils

from collections.abc import Awaitable, Callable, Iterable
from contextlib import asynccontextmanager, contextmanager
from typing import Any
from unittest.mock import AsyncMock

from ._mock_signal_backend import MockSignalBackend
from ._signal import Signal
from ._utils import T


def _get_mock_signal_backend(signal: Signal) -> MockSignalBackend:
    backend = signal._backend  # noqa:SLF001
    assert isinstance(backend, MockSignalBackend), (
        "Expected to receive a `MockSignalBackend`, instead "
        f" received {type(backend)}. "
    )
    return backend


[docs] def set_mock_value(signal: Signal[T], value: T): """Set the value of a signal that is in mock mode.""" backend = _get_mock_signal_backend(signal) backend.set_value(value)
[docs] def set_mock_put_proceeds(signal: Signal, proceeds: bool): """Allow or block a put with wait=True from proceeding""" backend = _get_mock_signal_backend(signal) if proceeds: backend.put_proceeds.set() else: backend.put_proceeds.clear()
@asynccontextmanager async def mock_puts_blocked(*signals: Signal): for signal in signals: set_mock_put_proceeds(signal, False) yield for signal in signals: set_mock_put_proceeds(signal, True)
[docs] def get_mock_put(signal: Signal) -> AsyncMock: """Get the mock associated with the put call on the signal.""" return _get_mock_signal_backend(signal).put_mock
def reset_mock_put_calls(signal: Signal): backend = _get_mock_signal_backend(signal) backend.put_mock.reset_mock() class _SetValuesIterator: # Garbage collected by the time __del__ is called unless we put it as a # global attrbute here. require_all_consumed: bool = False def __init__( self, signal: Signal, values: Iterable[Any], require_all_consumed: bool = False, ): self.signal = signal self.values = values self.require_all_consumed = require_all_consumed self.index = 0 self.iterator = enumerate(values, start=1) def __iter__(self): return self def __next__(self): # Will propogate StopIteration self.index, next_value = next(self.iterator) set_mock_value(self.signal, next_value) return next_value def __del__(self): if self.require_all_consumed: # Values is cast to a list here because the user has supplied # require_all_consumed=True, we can therefore assume they # supplied a finite list. # In the case of require_all_consumed=False, an infinite # iterble is permitted values = list(self.values) if self.index != len(values): # Report the values consumed and the values yet to be # consumed consumed = values[0 : self.index] to_be_consumed = values[self.index :] raise AssertionError( f"{self.signal.name}: {consumed} were consumed " f"but {to_be_consumed} were not consumed" )
[docs] def set_mock_values( signal: Signal, values: Iterable[Any], require_all_consumed: bool = False, ) -> _SetValuesIterator: """Iterator to set a signal to a sequence of values, optionally repeating the sequence. Parameters ---------- signal: A signal with a `MockSignalBackend` backend. values: An iterable of the values to set the signal to, on each iteration the value will be set. require_all_consumed: If True, an AssertionError will be raised if the iterator is deleted before all values have been consumed. Notes ----- Example usage:: for value_set in set_mock_values(signal, [1, 2, 3]): # do something cm = set_mock_values(signal, 1, 2, 3, require_all_consumed=True): next(cm) # do something """ return _SetValuesIterator( signal, values, require_all_consumed=require_all_consumed, )
@contextmanager def _unset_side_effect_cm(put_mock: AsyncMock): yield put_mock.side_effect = None
[docs] def callback_on_mock_put( signal: Signal[T], callback: Callable[[T], None] | Callable[[T], Awaitable[None]] ): """For setting a callback when a backend is put to. Can either be used in a context, with the callback being unset on exit, or as an ordinary function. Parameters ---------- signal: A signal with a `MockSignalBackend` backend. callback: The callback to call when the backend is put to during the context. """ backend = _get_mock_signal_backend(signal) backend.put_mock.side_effect = callback return _unset_side_effect_cm(backend.put_mock)