Using CleanImport to revert a reload of the os module doesn't work due to function registrations in copy_reg. The perils of reloading modules even for tests...
diff --git a/Lib/test/test_imp.py b/Lib/test/test_imp.py
index 1e62940..77e44be 100644
--- a/Lib/test/test_imp.py
+++ b/Lib/test/test_imp.py
@@ -43,7 +43,14 @@
reload()."""
def test_source(self):
- with test_support.CleanImport('os'):
+ # XXX (ncoghlan): It would be nice to use test_support.CleanImport
+ # here, but that breaks because the os module registers some
+ # handlers in copy_reg on import. Since CleanImport doesn't
+ # revert that registration, the module is left in a broken
+ # state after reversion. Reinitialising the module contents
+ # and just reverting os.environ to its previous state is an OK
+ # workaround
+ with test_support.EnvironmentVarGuard():
import os
imp.reload(os)
diff --git a/Lib/test/test_import.py b/Lib/test/test_import.py
index 4e0a686..31375dc 100644
--- a/Lib/test/test_import.py
+++ b/Lib/test/test_import.py
@@ -8,7 +8,7 @@
import warnings
import marshal
from test.test_support import (unlink, TESTFN, unload, run_unittest,
- check_warnings, TestFailed, CleanImport)
+ check_warnings, TestFailed, EnvironmentVarGuard)
def remove_files(name):
@@ -121,10 +121,22 @@
def testImpModule(self):
# Verify that the imp module can correctly load and find .py files
- import imp
- with CleanImport("os"):
+ import imp, os
+ # XXX (ncoghlan): It would be nice to use test_support.CleanImport
+ # here, but that breaks because the os module registers some
+ # handlers in copy_reg on import. Since CleanImport doesn't
+ # revert that registration, the module is left in a broken
+ # state after reversion. Reinitialising the module contents
+ # and just reverting os.environ to its previous state is an OK
+ # workaround
+ orig_path = os.path
+ orig_getenv = os.getenv
+ with EnvironmentVarGuard():
x = imp.find_module("os")
- os = imp.load_module("os", *x)
+ new_os = imp.load_module("os", *x)
+ self.assertIs(os, new_os)
+ self.assertIs(orig_path, new_os.path)
+ self.assertIsNot(orig_getenv, new_os.getenv)
def test_module_with_large_stack(self, module='longlist'):
# create module w/list of 65000 elements to test bug #561858