Coverage for python / lsst / dax / apdb / tests / utils.py: 62%

1# This file is part of dax_apdb. 

2# 

3# Developed for the LSST Data Management System. 

4# This product includes software developed by the LSST Project 

5# (http://www.lsst.org). 

6# See the COPYRIGHT file at the top-level directory of this distribution 

7# for details of code ownership. 

8# 

9# This program is free software: you can redistribute it and/or modify 

10# it under the terms of the GNU General Public License as published by 

11# the Free Software Foundation, either version 3 of the License, or 

12# (at your option) any later version. 

13# 

14# This program is distributed in the hope that it will be useful, 

15# but WITHOUT ANY WARRANTY; without even the implied warranty of 

16# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 

17# GNU General Public License for more details. 

18# 

19# You should have received a copy of the GNU General Public License 

20# along with this program. If not, see <http://www.gnu.org/licenses/>. 

21 

22from __future__ import annotations 

23 

24__all__ = ["TestCaseMixin", "modified_environment"] 

25 

26import contextlib 

27import os 

28import unittest 

29from collections.abc import Iterator 

30from typing import TYPE_CHECKING 

31 

32if TYPE_CHECKING: 

33 

34 class TestCaseMixin(unittest.TestCase): 

35 """Base class for mixin test classes that use TestCase methods.""" 

36 

37else: 

38 

39 class TestCaseMixin: 

40 """Do-nothing definition of mixin base class for regular execution.""" 

41 

42 

43# Stolen from daf_butler 

44@contextlib.contextmanager 

45def modified_environment(**environ: str) -> Iterator[None]: 

46 """Temporarily set environment variables. 

47 

48 Parameters 

49 ---------- 

50 **environ : `dict` 

51 Key value pairs of environment variables to temporarily set. 

52 """ 

53 old_environ = dict(os.environ) 

54 os.environ.update(environ) 

55 try: 

56 yield 

57 finally: 

58 os.environ.clear() 

59 os.environ.update(old_environ)