--- a/python/mach_commands.py
+++ b/python/mach_commands.py
@@ -1,29 +1,30 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 from __future__ import absolute_import, print_function, unicode_literals
 
 import argparse
 import logging
-import mozpack.path as mozpath
 import os
+import tempfile
 
 from concurrent.futures import (
     ThreadPoolExecutor,
     as_completed,
     thread,
 )
 
 import mozinfo
 from manifestparser import TestManifest
 from manifestparser import filters as mpf
 
+import mozpack.path as mozpath
 from mozbuild.base import (
     MachCommandBase,
 )
 
 from mach.decorators import (
     CommandArgument,
     CommandProvider,
     Command,
@@ -64,23 +65,31 @@ class MachCommands(MachCommandBase):
     @CommandArgument('--subsuite',
         default=None,
         help=('Python subsuite to run. If not specified, all subsuites are run. '
              'Use the string `default` to only run tests without a subsuite.'))
     @CommandArgument('tests', nargs='*',
         metavar='TEST',
         help=('Tests to run. Each test can be a single file or a directory. '
               'Default test resolution relies on PYTHON_UNITTEST_MANIFESTS.'))
-    def python_test(self,
-                    tests=[],
-                    test_objects=None,
-                    subsuite=None,
-                    verbose=False,
-                    stop=False,
-                    jobs=1):
+    def python_test(self, *args, **kwargs):
+        try:
+            tempdir = os.environ[b'PYTHON_TEST_TMP'] = str(tempfile.mkdtemp(suffix='-python-test'))
+            return self.run_python_tests(*args, **kwargs)
+        finally:
+            import mozfile
+            mozfile.remove(tempdir)
+
+    def run_python_tests(self,
+                         tests=[],
+                         test_objects=None,
+                         subsuite=None,
+                         verbose=False,
+                         stop=False,
+                         jobs=1):
         self._activate_virtualenv()
 
         def find_tests_by_path():
             import glob
             files = []
             for t in tests:
                 if t.endswith('.py') and os.path.isfile(t):
                     files.append(t)