Source code for functional_harness.env_general

"""Assorted context managers for setting up the test environment"""

__author__ = "Stephan Sokolow (deitarion/SSokolow)"
__license__ = "MIT"

import os, subprocess  # nosec
from contextlib import contextmanager

# Silence PyLint being flat-out wrong about MyPy type annotations
# pylint: disable=unsubscriptable-object

# -- Type-Annotation Imports --
from typing import Any, Dict, Generator  # NOQA

[docs]@contextmanager def background_proc(argv, verbose=False, *args: Any, **kwargs: Any ) -> Generator[None, None, None]: """Context manager for scoping the lifetime of a ``subprocess.Popen`` call :param argv: The command to be executed :param verbose: If :any:`False`, redirect the X server's ``stdout`` and ``stderr`` to :file:`/dev/null` :param args: Positional arguments to pass to :class:`subprocess.Popen` :param kwargs: Keyword arguments to pass to :class:`subprocess.Popen` """ if verbose: popen_obj = subprocess.Popen(argv, *args, **kwargs) # nosec else: popen_obj = subprocess.Popen(argv, # type: ignore stderr=subprocess.STDOUT, stdout=subprocess.DEVNULL, *args, **kwargs) try: yield finally: popen_obj.terminate()
[docs]@contextmanager def env_vars(new: Dict[str, str]) -> Generator[None, None, None]: """Context manager to temporarily change environment variables :param new: Items to be added to :any:`os.environ` for the lifetime of the context manager. """ old_vals = {} try: for key, val in new.items(): if key in os.environ: old_vals[key] = os.environ[key] os.environ[key] = val yield finally: for key, val in old_vals.items(): os.environ[key] = val