cpython/Lib/test/test_import.py

229 lines
7.5 KiB
Python

from test.test_support import TESTFN, run_unittest, guard_warnings_filter
import unittest
import os
import random
import sys
import py_compile
import warnings
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("# This tests Python's ability to import a", ext, "file.", file=f)
a = random.randrange(1000)
b = random.randrange(1000)
print("a =", a, file=f)
print("b =", b, file=f)
f.close()
try:
try:
mod = __import__(TESTFN)
except ImportError as 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 as 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("a = 1/0", file=f)
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("a = 1", file=f)
print("b = 2", file=f)
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("a = 10", file=f)
print("b = 20//0", file=f)
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 guard_warnings_filter():
# 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_main(verbose=None):
run_unittest(ImportTest)
if __name__ == '__main__':
test_main()