cpython/Lib/test/test_import.py
Brett Cannon 672237dc6c warnings.catch_warnings() now returns a list or None instead of the custom
WarningsRecorder object. This makes the API simpler to use as no special object
must be learned.

Closes issue 3781.
Review by Benjamin Peterson.
2008-09-09 00:49:16 +00:00

305 lines
10 KiB
Python

import unittest
import os
import random
import shutil
import sys
import py_compile
import warnings
from test.test_support import unlink, TESTFN, unload, run_unittest
def remove_files(name):
for f in (name + os.extsep + "py",
name + os.extsep + "pyc",
name + os.extsep + "pyo",
name + os.extsep + "pyw",
name + "$py.class"):
if os.path.exists(f):
os.remove(f)
class ImportTest(unittest.TestCase):
def testCaseSensitivity(self):
# Brief digression to test that import is case-sensitive: if we got this
# far, we know for sure that "random" exists.
try:
import RAnDoM
except ImportError:
pass
else:
self.fail("import of RAnDoM should have failed (case mismatch)")
def testDoubleConst(self):
# Another brief digression to test the accuracy of manifest float constants.
from test import double_const # don't blink -- that *was* the test
def testImport(self):
def test_with_extension(ext):
# ext normally ".py"; perhaps ".pyw"
source = TESTFN + ext
pyo = TESTFN + os.extsep + "pyo"
if sys.platform.startswith('java'):
pyc = TESTFN + "$py.class"
else:
pyc = TESTFN + os.extsep + "pyc"
f = open(source, "w")
print >> f, "# This tests Python's ability to import a", ext, "file."
a = random.randrange(1000)
b = random.randrange(1000)
print >> f, "a =", a
print >> f, "b =", b
f.close()
try:
try:
mod = __import__(TESTFN)
except ImportError, err:
self.fail("import from %s failed: %s" % (ext, err))
self.assertEquals(mod.a, a,
"module loaded (%s) but contents invalid" % mod)
self.assertEquals(mod.b, b,
"module loaded (%s) but contents invalid" % mod)
finally:
os.unlink(source)
try:
try:
reload(mod)
except ImportError, err:
self.fail("import from .pyc/.pyo failed: %s" % err)
finally:
try:
os.unlink(pyc)
except OSError:
pass
try:
os.unlink(pyo)
except OSError:
pass
del sys.modules[TESTFN]
sys.path.insert(0, os.curdir)
try:
test_with_extension(os.extsep + "py")
if sys.platform.startswith("win"):
for ext in ".PY", ".Py", ".pY", ".pyw", ".PYW", ".pYw":
test_with_extension(ext)
finally:
del sys.path[0]
def testImpModule(self):
# Verify that the imp module can correctly load and find .py files
import imp
x = imp.find_module("os")
os = imp.load_module("os", *x)
def test_module_with_large_stack(self, module='longlist'):
# create module w/list of 65000 elements to test bug #561858
filename = module + os.extsep + 'py'
# create a file with a list of 65000 elements
f = open(filename, 'w+')
f.write('d = [\n')
for i in range(65000):
f.write('"",\n')
f.write(']')
f.close()
# compile & remove .py file, we only need .pyc (or .pyo)
f = open(filename, 'r')
py_compile.compile(filename)
f.close()
os.unlink(filename)
# need to be able to load from current dir
sys.path.append('')
# this used to crash
exec 'import ' + module
# cleanup
del sys.path[-1]
for ext in 'pyc', 'pyo':
fname = module + os.extsep + ext
if os.path.exists(fname):
os.unlink(fname)
def test_failing_import_sticks(self):
source = TESTFN + os.extsep + "py"
f = open(source, "w")
print >> f, "a = 1/0"
f.close()
# New in 2.4, we shouldn't be able to import that no matter how often
# we try.
sys.path.insert(0, os.curdir)
try:
for i in 1, 2, 3:
try:
mod = __import__(TESTFN)
except ZeroDivisionError:
if TESTFN in sys.modules:
self.fail("damaged module in sys.modules on %i. try" % i)
else:
self.fail("was able to import a damaged module on %i. try" % i)
finally:
sys.path.pop(0)
remove_files(TESTFN)
def test_failing_reload(self):
# A failing reload should leave the module object in sys.modules.
source = TESTFN + os.extsep + "py"
f = open(source, "w")
print >> f, "a = 1"
print >> f, "b = 2"
f.close()
sys.path.insert(0, os.curdir)
try:
mod = __import__(TESTFN)
self.assert_(TESTFN in sys.modules, "expected module in sys.modules")
self.assertEquals(mod.a, 1, "module has wrong attribute values")
self.assertEquals(mod.b, 2, "module has wrong attribute values")
# On WinXP, just replacing the .py file wasn't enough to
# convince reload() to reparse it. Maybe the timestamp didn't
# move enough. We force it to get reparsed by removing the
# compiled file too.
remove_files(TESTFN)
# Now damage the module.
f = open(source, "w")
print >> f, "a = 10"
print >> f, "b = 20//0"
f.close()
self.assertRaises(ZeroDivisionError, reload, mod)
# But we still expect the module to be in sys.modules.
mod = sys.modules.get(TESTFN)
self.failIf(mod is None, "expected module to still be in sys.modules")
# We should have replaced a w/ 10, but the old b value should
# stick.
self.assertEquals(mod.a, 10, "module has wrong attribute values")
self.assertEquals(mod.b, 2, "module has wrong attribute values")
finally:
sys.path.pop(0)
remove_files(TESTFN)
if TESTFN in sys.modules:
del sys.modules[TESTFN]
def test_infinite_reload(self):
# Bug #742342 reports that Python segfaults (infinite recursion in C)
# when faced with self-recursive reload()ing.
sys.path.insert(0, os.path.dirname(__file__))
try:
import infinite_reload
finally:
sys.path.pop(0)
def test_import_name_binding(self):
# import x.y.z binds x in the current namespace
import test as x
import test.test_support
self.assert_(x is test, x.__name__)
self.assert_(hasattr(test.test_support, "__file__"))
# import x.y.z as w binds z as w
import test.test_support as y
self.assert_(y is test.test_support, y.__name__)
def test_import_initless_directory_warning(self):
with warnings.catch_warnings():
# Just a random non-package directory we always expect to be
# somewhere in sys.path...
warnings.simplefilter('error', ImportWarning)
self.assertRaises(ImportWarning, __import__, "site-packages")
def test_importbyfilename(self):
path = os.path.abspath(TESTFN)
try:
__import__(path)
except ImportError, err:
self.assertEqual("Import by filename is not supported.",
err.args[0])
else:
self.fail("import by path didn't raise an exception")
class PathsTests(unittest.TestCase):
path = TESTFN
def setUp(self):
os.mkdir(self.path)
self.syspath = sys.path[:]
def tearDown(self):
shutil.rmtree(self.path)
sys.path = self.syspath
# http://bugs.python.org/issue1293
def test_trailing_slash(self):
f = open(os.path.join(self.path, 'test_trailing_slash.py'), 'w')
f.write("testdata = 'test_trailing_slash'")
f.close()
sys.path.append(self.path+'/')
mod = __import__("test_trailing_slash")
self.assertEqual(mod.testdata, 'test_trailing_slash')
unload("test_trailing_slash")
class RelativeImport(unittest.TestCase):
def tearDown(self):
try:
del sys.modules["test.relimport"]
except:
pass
def test_relimport_star(self):
# This will import * from .test_import.
from . import relimport
self.assertTrue(hasattr(relimport, "RelativeImport"))
def test_issue3221(self):
def check_absolute():
exec "from os import path" in ns
def check_relative():
exec "from . import relimport" in ns
# Check both OK with __package__ and __name__ correct
ns = dict(__package__='test', __name__='test.notarealmodule')
check_absolute()
check_relative()
# Check both OK with only __name__ wrong
ns = dict(__package__='test', __name__='notarealpkg.notarealmodule')
check_absolute()
check_relative()
# Check relative fails with only __package__ wrong
ns = dict(__package__='foo', __name__='test.notarealmodule')
with warnings.catch_warnings(record=True) as w:
check_absolute()
self.assert_('foo' in str(w[-1].message))
self.assertEqual(w[-1].category, RuntimeWarning)
self.assertRaises(SystemError, check_relative)
# Check relative fails with __package__ and __name__ wrong
ns = dict(__package__='foo', __name__='notarealpkg.notarealmodule')
with warnings.catch_warnings(record=True) as w:
check_absolute()
self.assert_('foo' in str(w[-1].message))
self.assertEqual(w[-1].category, RuntimeWarning)
self.assertRaises(SystemError, check_relative)
# Check both fail with package set to a non-string
ns = dict(__package__=object())
self.assertRaises(ValueError, check_absolute)
self.assertRaises(ValueError, check_relative)
def test_main(verbose=None):
run_unittest(ImportTest, PathsTests, RelativeImport)
if __name__ == '__main__':
# test needs to be a package, so we can do relative import
from test.test_import import test_main
test_main()