Use testpath to temporarily modify environment variables

IPython/core/tests/test_paths.py

@@ -1,246 +1,250 b''
 from contextlib import contextmanager
 import errno
 import os
 import shutil
 import sys
 import tempfile
 import warnings
 
 try:
     reload
 except NameError:   # Python 3
     from imp import reload
 
 from nose import with_setup
 import nose.tools as nt
+from testpath import modified_env
 
 import IPython
 from IPython import paths
 from IPython.testing.decorators import skip_win32
 from IPython.utils.tempdir import TemporaryDirectory
 
 env = os.environ
 TMP_TEST_DIR = tempfile.mkdtemp()
 HOME_TEST_DIR = os.path.join(TMP_TEST_DIR, "home_test_dir")
 XDG_TEST_DIR = os.path.join(HOME_TEST_DIR, "xdg_test_dir")
 XDG_CACHE_DIR = os.path.join(HOME_TEST_DIR, "xdg_cache_dir")
 IP_TEST_DIR = os.path.join(HOME_TEST_DIR,'.ipython')
 
 def setup():
     """Setup testenvironment for the module:
 
             - Adds dummy home dir tree
     """
     # Do not mask exceptions here.  In particular, catching WindowsError is a
     # problem because that exception is only defined on Windows...
     os.makedirs(IP_TEST_DIR)
     os.makedirs(os.path.join(XDG_TEST_DIR, 'ipython'))
     os.makedirs(os.path.join(XDG_CACHE_DIR, 'ipython'))
 
 
 def teardown():
     """Teardown testenvironment for the module:
 
             - Remove dummy home dir tree
     """
     # Note: we remove the parent test dir, which is the root of all test
     # subdirs we may have created.  Use shutil instead of os.removedirs, so
     # that non-empty directories are all recursively removed.
     shutil.rmtree(TMP_TEST_DIR)
 
 
 def setup_environment():
     """Setup testenvironment for some functions that are tested
     in this module. In particular this functions stores attributes
     and other things that we need to stub in some test functions.
     This needs to be done on a function level and not module level because
     each testfunction needs a pristine environment.
     """
-    global oldstuff, platformstuff
-    oldstuff = (env.copy(), os.name, sys.platform, paths.get_home_dir, IPython.__file__, os.getcwd())
+    global oldstuff
+    oldstuff = (os.name, sys.platform, paths.get_home_dir, IPython.__file__, os.getcwd())
 
 def teardown_environment():
     """Restore things that were remembered by the setup_environment function
     """
-    (oldenv, os.name, sys.platform, paths.get_home_dir, IPython.__file__, old_wd) = oldstuff
+    (os.name, sys.platform, paths.get_home_dir, IPython.__file__, old_wd) = oldstuff
     os.chdir(old_wd)
     reload(paths)
 
-    for key in list(env):
-        if key not in oldenv:
-            del env[key]
-    env.update(oldenv)
     if hasattr(sys, 'frozen'):
         del sys.frozen
 
 # Build decorator that uses the setup_environment/setup_environment
 with_environment = with_setup(setup_environment, teardown_environment)
 
 @contextmanager
 def patch_get_home_dir(dirpath):
     orig_get_home_dir = paths.get_home_dir
     paths.get_home_dir = lambda : dirpath
     try:
         yield
     finally:
         paths.get_home_dir = orig_get_home_dir
 
-
-@with_environment
 def test_get_ipython_dir_1():
     """test_get_ipython_dir_1, Testcase to see if we can call get_ipython_dir without Exceptions."""
     env_ipdir = os.path.join("someplace", ".ipython")
     paths._writable_dir = lambda path: True
-    env['IPYTHONDIR'] = env_ipdir
-    ipdir = paths.get_ipython_dir()
-    nt.assert_equal(ipdir, env_ipdir)
+    with modified_env({'IPYTHONDIR': env_ipdir}):
+        ipdir = paths.get_ipython_dir()
 
+    nt.assert_equal(ipdir, env_ipdir)
 
 @with_environment
 def test_get_ipython_dir_2():
     """test_get_ipython_dir_2, Testcase to see if we can call get_ipython_dir without Exceptions."""
     with patch_get_home_dir('someplace'):
         paths.get_xdg_dir = lambda : None
         paths._writable_dir = lambda path: True
         os.name = "posix"
-        env.pop('IPYTHON_DIR', None)
-        env.pop('IPYTHONDIR', None)
-        env.pop('XDG_CONFIG_HOME', None)
-        ipdir = paths.get_ipython_dir()
+        with modified_env({'IPYTHON_DIR': None,
+                           'IPYTHONDIR': None,
+                           'XDG_CONFIG_HOME': None
+                          }):
+            ipdir = paths.get_ipython_dir()
+
         nt.assert_equal(ipdir, os.path.join("someplace", ".ipython"))
 
 @with_environment
 def test_get_ipython_dir_3():
     """test_get_ipython_dir_3, move XDG if defined, and .ipython doesn't exist."""
     tmphome = TemporaryDirectory()
     try:
         with patch_get_home_dir(tmphome.name):
             os.name = "posix"
-            env.pop('IPYTHON_DIR', None)
-            env.pop('IPYTHONDIR', None)
-            env['XDG_CONFIG_HOME'] = XDG_TEST_DIR
-
-            with warnings.catch_warnings(record=True) as w:
+            with modified_env({
+                'IPYTHON_DIR': None,
+                'IPYTHONDIR': None,
+                'XDG_CONFIG_HOME': XDG_TEST_DIR,
+            }), warnings.catch_warnings(record=True) as w:
                 ipdir = paths.get_ipython_dir()
 
             nt.assert_equal(ipdir, os.path.join(tmphome.name, ".ipython"))
             if sys.platform != 'darwin':
                 nt.assert_equal(len(w), 1)
                 nt.assert_in('Moving', str(w[0]))
     finally:
         tmphome.cleanup()
 
 @with_environment
 def test_get_ipython_dir_4():
     """test_get_ipython_dir_4, warn if XDG and home both exist."""
     with patch_get_home_dir(HOME_TEST_DIR):
         os.name = "posix"
-        env.pop('IPYTHON_DIR', None)
-        env.pop('IPYTHONDIR', None)
-        env['XDG_CONFIG_HOME'] = XDG_TEST_DIR
         try:
             os.mkdir(os.path.join(XDG_TEST_DIR, 'ipython'))
         except OSError as e:
             if e.errno != errno.EEXIST:
                 raise
 
-        with warnings.catch_warnings(record=True) as w:
+
+        with modified_env({
+            'IPYTHON_DIR': None,
+            'IPYTHONDIR': None,
+            'XDG_CONFIG_HOME': XDG_TEST_DIR,
+        }), warnings.catch_warnings(record=True) as w:
             ipdir = paths.get_ipython_dir()
 
         nt.assert_equal(ipdir, os.path.join(HOME_TEST_DIR, ".ipython"))
         if sys.platform != 'darwin':
             nt.assert_equal(len(w), 1)
             nt.assert_in('Ignoring', str(w[0]))
 
 @with_environment
 def test_get_ipython_dir_5():
     """test_get_ipython_dir_5, use .ipython if exists and XDG defined, but doesn't exist."""
     with patch_get_home_dir(HOME_TEST_DIR):
         os.name = "posix"
-        env.pop('IPYTHON_DIR', None)
-        env.pop('IPYTHONDIR', None)
-        env['XDG_CONFIG_HOME'] = XDG_TEST_DIR
         try:
             os.rmdir(os.path.join(XDG_TEST_DIR, 'ipython'))
         except OSError as e:
             if e.errno != errno.ENOENT:
                 raise
-        ipdir = paths.get_ipython_dir()
+
+        with modified_env({
+            'IPYTHON_DIR': None,
+            'IPYTHONDIR': None,
+            'XDG_CONFIG_HOME': XDG_TEST_DIR,
+        }):
+            ipdir = paths.get_ipython_dir()
+
         nt.assert_equal(ipdir, IP_TEST_DIR)
 
 @with_environment
 def test_get_ipython_dir_6():
     """test_get_ipython_dir_6, use home over XDG if defined and neither exist."""
     xdg = os.path.join(HOME_TEST_DIR, 'somexdg')
     os.mkdir(xdg)
     shutil.rmtree(os.path.join(HOME_TEST_DIR, '.ipython'))
     with patch_get_home_dir(HOME_TEST_DIR):
         orig_get_xdg_dir = paths.get_xdg_dir
         paths.get_xdg_dir = lambda : xdg
         try:
             os.name = "posix"
-            env.pop('IPYTHON_DIR', None)
-            env.pop('IPYTHONDIR', None)
-            env.pop('XDG_CONFIG_HOME', None)
-            with warnings.catch_warnings(record=True) as w:
+            with modified_env({
+                'IPYTHON_DIR': None,
+                'IPYTHONDIR': None,
+                'XDG_CONFIG_HOME': None,
+            }), warnings.catch_warnings(record=True) as w:
                 ipdir = paths.get_ipython_dir()
 
             nt.assert_equal(ipdir, os.path.join(HOME_TEST_DIR, '.ipython'))
             nt.assert_equal(len(w), 0)
         finally:
             paths.get_xdg_dir = orig_get_xdg_dir
 
-@with_environment
 def test_get_ipython_dir_7():
     """test_get_ipython_dir_7, test home directory expansion on IPYTHONDIR"""
     paths._writable_dir = lambda path: True
     home_dir = os.path.normpath(os.path.expanduser('~'))
-    env['IPYTHONDIR'] = os.path.join('~', 'somewhere')
-    ipdir = paths.get_ipython_dir()
+    with modified_env({'IPYTHONDIR': os.path.join('~', 'somewhere')}):
+        ipdir = paths.get_ipython_dir()
     nt.assert_equal(ipdir, os.path.join(home_dir, 'somewhere'))
 
 @skip_win32
-@with_environment
 def test_get_ipython_dir_8():
     """test_get_ipython_dir_8, test / home directory"""
     old = paths._writable_dir, paths.get_xdg_dir
     try:
         paths._writable_dir = lambda path: bool(path)
         paths.get_xdg_dir = lambda: None
-        env.pop('IPYTHON_DIR', None)
-        env.pop('IPYTHONDIR', None)
-        env['HOME'] = '/'
-        nt.assert_equal(paths.get_ipython_dir(), '/.ipython')
+        with modified_env({
+            'IPYTHON_DIR': None,
+            'IPYTHONDIR': None,
+            'HOME': '/',
+        }):
+            nt.assert_equal(paths.get_ipython_dir(), '/.ipython')
     finally:
         paths._writable_dir, paths.get_xdg_dir = old
 
 
 @with_environment
 def test_get_ipython_cache_dir():
-    os.environ["HOME"] = HOME_TEST_DIR
-    if os.name == 'posix' and sys.platform != 'darwin':
-        # test default
-        os.makedirs(os.path.join(HOME_TEST_DIR, ".cache"))
-        os.environ.pop("XDG_CACHE_HOME", None)
-        ipdir = paths.get_ipython_cache_dir()
-        nt.assert_equal(os.path.join(HOME_TEST_DIR, ".cache", "ipython"),
-                        ipdir)
-        nt.assert_true(os.path.isdir(ipdir))
-
-        # test env override
-        os.environ["XDG_CACHE_HOME"] = XDG_CACHE_DIR
-        ipdir = paths.get_ipython_cache_dir()
-        nt.assert_true(os.path.isdir(ipdir))
-        nt.assert_equal(ipdir, os.path.join(XDG_CACHE_DIR, "ipython"))
-    else:
-        nt.assert_equal(paths.get_ipython_cache_dir(),
-                        paths.get_ipython_dir())
+    with modified_env({'HOME': HOME_TEST_DIR}):
+        if os.name == 'posix' and sys.platform != 'darwin':
+            # test default
+            os.makedirs(os.path.join(HOME_TEST_DIR, ".cache"))
+            with modified_env({'XDG_CACHE_HOME': None}):
+                ipdir = paths.get_ipython_cache_dir()
+            nt.assert_equal(os.path.join(HOME_TEST_DIR, ".cache", "ipython"),
+                            ipdir)
+            nt.assert_true(os.path.isdir(ipdir))
+
+            # test env override
+            with modified_env({"XDG_CACHE_HOME": XDG_CACHE_DIR}):
+                ipdir = paths.get_ipython_cache_dir()
+            nt.assert_true(os.path.isdir(ipdir))
+            nt.assert_equal(ipdir, os.path.join(XDG_CACHE_DIR, "ipython"))
+        else:
+            nt.assert_equal(paths.get_ipython_cache_dir(),
+                            paths.get_ipython_dir())
 
 def test_get_ipython_package_dir():
     ipdir = paths.get_ipython_package_dir()
     nt.assert_true(os.path.isdir(ipdir))
 
 
 def test_get_ipython_module_path():
     ipapp_path = paths.get_ipython_module_path('IPython.terminal.ipapp')
     nt.assert_true(os.path.isfile(ipapp_path))