Use mock to patch for TZ env var

tests/conftest.py

@@ -6,6 +6,7 @@ import re
 import shutil
 import subprocess
 import sys
+import time
 from contextlib import contextmanager
 
 import pytest
@@ -556,3 +557,13 @@ def mock_server():
     test_server = MockServer(server)
     with test_server.context:
         yield test_server
+
+
+@pytest.fixture
+def utc():
+    # time.tzset() is not implemented on some platforms, e.g. Windows.
+    tzset = getattr(time, 'tzset', lambda: None)
+    with patch.dict(os.environ, {'TZ': 'UTC'}):
+        tzset()
+        yield
+    tzset()

tests/unit/test_base_command.py

@@ -1,6 +1,5 @@
 import logging
 import os
-import time
 
 import pytest
 from mock import Mock, patch
@@ -12,6 +11,12 @@ from pip._internal.utils.logging import BrokenStdoutLoggingError
 from pip._internal.utils.temp_dir import TempDirectory
 
 
+@pytest.fixture
+def fixed_time(utc):
+    with patch('time.time', lambda: 1547704837.040001):
+        yield
+
+
 class FakeCommand(Command):
 
     _name = 'fake'
@@ -91,67 +96,40 @@ def test_handle_pip_version_check_called(mock_handle_version_check):
     mock_handle_version_check.assert_called_once()
 
 
-class Test_base_command_logging(object):
+def test_log_command_success(fixed_time, tmpdir):
+    """Test the --log option logs when command succeeds."""
+    cmd = FakeCommand()
+    log_path = tmpdir.joinpath('log')
+    cmd.main(['fake', '--log', log_path])
+    with open(log_path) as f:
+        assert f.read().rstrip() == '2019-01-17T06:00:37,040 fake'
+
+
+def test_log_command_error(fixed_time, tmpdir):
+    """Test the --log option logs when command fails."""
+    cmd = FakeCommand(error=True)
+    log_path = tmpdir.joinpath('log')
+    cmd.main(['fake', '--log', log_path])
+    with open(log_path) as f:
+        assert f.read().startswith('2019-01-17T06:00:37,040 fake')
+
+
+def test_log_file_command_error(fixed_time, tmpdir):
+    """Test the --log-file option logs (when there's an error)."""
+    cmd = FakeCommand(error=True)
+    log_file_path = tmpdir.joinpath('log_file')
+    cmd.main(['fake', '--log-file', log_file_path])
+    with open(log_file_path) as f:
+        assert f.read().startswith('2019-01-17T06:00:37,040 fake')
+
+
+def test_log_unicode_messages(fixed_time, tmpdir):
+    """Tests that logging bytestrings and unicode objects
+    don't break logging.
     """
-    Test `pip.base_command.Command` setting up logging consumers based on
-    options
-    """
-
-    def setup(self):
-        self.old_time = time.time
-        time.time = lambda: 1547704837.040001
-        self.old_tz = os.environ.get('TZ')
-        os.environ['TZ'] = 'UTC'
-        # time.tzset() is not implemented on some platforms (notably, Windows).
-        if hasattr(time, 'tzset'):
-            time.tzset()
-
-    def teardown(self):
-        if self.old_tz:
-            os.environ['TZ'] = self.old_tz
-        else:
-            del os.environ['TZ']
-        if 'tzset' in dir(time):
-            time.tzset()
-        time.time = self.old_time
-
-    def test_log_command_success(self, tmpdir):
-        """
-        Test the --log option logs when command succeeds
-        """
-        cmd = FakeCommand()
-        log_path = tmpdir.joinpath('log')
-        cmd.main(['fake', '--log', log_path])
-        with open(log_path) as f:
-            assert f.read().rstrip() == '2019-01-17T06:00:37,040 fake'
-
-    def test_log_command_error(self, tmpdir):
-        """
-        Test the --log option logs when command fails
-        """
-        cmd = FakeCommand(error=True)
-        log_path = tmpdir.joinpath('log')
-        cmd.main(['fake', '--log', log_path])
-        with open(log_path) as f:
-            assert f.read().startswith('2019-01-17T06:00:37,040 fake')
-
-    def test_log_file_command_error(self, tmpdir):
-        """
-        Test the --log-file option logs (when there's an error).
-        """
-        cmd = FakeCommand(error=True)
-        log_file_path = tmpdir.joinpath('log_file')
-        cmd.main(['fake', '--log-file', log_file_path])
-        with open(log_file_path) as f:
-            assert f.read().startswith('2019-01-17T06:00:37,040 fake')
-
-    def test_unicode_messages(self, tmpdir):
-        """
-        Tests that logging bytestrings and unicode objects don't break logging
-        """
-        cmd = FakeCommandWithUnicode()
-        log_path = tmpdir.joinpath('log')
-        cmd.main(['fake_unicode', '--log', log_path])
+    cmd = FakeCommandWithUnicode()
+    log_path = tmpdir.joinpath('log')
+    cmd.main(['fake_unicode', '--log', log_path])
 
 
 @pytest.mark.no_auto_tempdir_manager

tests/unit/test_logging.py

@@ -1,7 +1,5 @@
 import errno
 import logging
-import os
-import time
 from threading import Thread
 
 import pytest
@@ -33,24 +31,7 @@ def _make_broken_pipe_error():
 
 
 class TestIndentingFormatter(object):
-    """
-    Test `pip._internal.utils.logging.IndentingFormatter`.
-    """
-
-    def setup(self):
-        self.old_tz = os.environ.get('TZ')
-        os.environ['TZ'] = 'UTC'
-        # time.tzset() is not implemented on some platforms (notably, Windows).
-        if hasattr(time, 'tzset'):
-            time.tzset()
-
-    def teardown(self):
-        if self.old_tz:
-            os.environ['TZ'] = self.old_tz
-        else:
-            del os.environ['TZ']
-        if 'tzset' in dir(time):
-            time.tzset()
+    """Test ``pip._internal.utils.logging.IndentingFormatter``."""
 
     def make_record(self, msg, level_name):
         level_number = getattr(logging, level_name)
@@ -72,7 +53,7 @@ class TestIndentingFormatter(object):
         ('ERROR', 'ERROR: hello\nworld'),
         ('CRITICAL', 'ERROR: hello\nworld'),
     ])
-    def test_format(self, level_name, expected):
+    def test_format(self, level_name, expected, utc):
         """
         Args:
           level_name: a logging level name (e.g. "WARNING").
@@ -89,7 +70,7 @@ class TestIndentingFormatter(object):
          '2019-01-17T06:00:37,040 WARNING: hello\n'
          '2019-01-17T06:00:37,040 world'),
     ])
-    def test_format_with_timestamp(self, level_name, expected):
+    def test_format_with_timestamp(self, level_name, expected, utc):
         record = self.make_record('hello\nworld', level_name=level_name)
         f = IndentingFormatter(fmt="%(message)s", add_timestamp=True)
         assert f.format(record) == expected
@@ -99,7 +80,7 @@ class TestIndentingFormatter(object):
         ('ERROR', 'DEPRECATION: hello\nworld'),
         ('CRITICAL', 'DEPRECATION: hello\nworld'),
     ])
-    def test_format_deprecated(self, level_name, expected):
+    def test_format_deprecated(self, level_name, expected, utc):
         """
         Test that logged deprecation warnings coming from deprecated()
         don't get another prefix.
@@ -110,7 +91,7 @@ class TestIndentingFormatter(object):
         f = IndentingFormatter(fmt="%(message)s")
         assert f.format(record) == expected
 
-    def test_thread_safety_base(self):
+    def test_thread_safety_base(self, utc):
         record = self.make_record(
             'DEPRECATION: hello\nworld', level_name='WARNING',
         )
@@ -126,7 +107,7 @@ class TestIndentingFormatter(object):
         thread.join()
         assert results[0] == results[1]
 
-    def test_thread_safety_indent_log(self):
+    def test_thread_safety_indent_log(self, utc):
         record = self.make_record(
             'DEPRECATION: hello\nworld', level_name='WARNING',
         )