subprocess and environment test behavior

.gitignore

__pycache__

__init__.py

""" base init class, changing the bash environment for process """

import os
from unittest import TestCase

class BaseTests(TestCase):
    """Large framework base utilities"""

    def setUp(self):
        print("setUp in BaseTests")
        super().setUp()
        self.original_env = os.environ.copy()
        # change an exesting environment variable for all tests
        os.environ["SHELL"] = "/bin/foo"
        print("--- environ in process ---")
        print(os.environ)

    def tearDown(self):
        os.environ = self.original_env
        print("--- restored environ ---")
        print(os.environ)
        super().tearDown()

failing

#!/bin/bash

echo "Failing by running all tests"
export http_proxy="FOOPROXY"
nosetests3 -s .

success

#!/bin/sh

echo "Success by running only B tests"
export http_proxy="FOOPROXY"
nosetests3 -s test_b.py

test_a.py

""" First test class doing nothing """

from . import BaseTests


class A(BaseTests):

    def test_foo(self):
        pass

test_b.py

""" Real test class impacted by the presence of A """

from . import BaseTests
import os
import subprocess


class B(BaseTests):

    @classmethod
    def setUpClass(cls):
        super().setUpClass()
        print("\n------------------------------\nRemoving http_proxy env variable for all tests of this class")
        cls.proxy_env = os.environ.pop("http_proxy", None)

    @classmethod
    def tearDownClass(cls):
        super().tearDownClass()
        if cls.proxy_env:
           os.environ["http_proxy"] = cls.proxy_env

    def test_foo(self):
        env_output = subprocess.check_output(["env"]).decode("utf-8")
        print("--- env subprocess ---")
        print(env_output)
        self.assertNotIn("http_proxy=", env_output)