cpython/Lib/test/test_file2k.py

576 lines
19 KiB
Python

import sys
import os
import unittest
import itertools
import time
import threading
from array import array
from weakref import proxy
from test import test_support
from test.test_support import TESTFN, findfile, run_unittest
from UserList import UserList
class AutoFileTests(unittest.TestCase):
# file tests for which a test file is automatically set up
def setUp(self):
self.f = open(TESTFN, 'wb')
def tearDown(self):
if self.f:
self.f.close()
os.remove(TESTFN)
def testWeakRefs(self):
# verify weak references
p = proxy(self.f)
p.write('teststring')
self.assertEquals(self.f.tell(), p.tell())
self.f.close()
self.f = None
self.assertRaises(ReferenceError, getattr, p, 'tell')
def testAttributes(self):
# verify expected attributes exist
f = self.f
softspace = f.softspace
f.name # merely shouldn't blow up
f.mode # ditto
f.closed # ditto
# verify softspace is writable
f.softspace = softspace # merely shouldn't blow up
# verify the others aren't
for attr in 'name', 'mode', 'closed':
self.assertRaises((AttributeError, TypeError), setattr, f, attr, 'oops')
def testReadinto(self):
# verify readinto
self.f.write('12')
self.f.close()
a = array('c', 'x'*10)
self.f = open(TESTFN, 'rb')
n = self.f.readinto(a)
self.assertEquals('12', a.tostring()[:n])
def testWritelinesUserList(self):
# verify writelines with instance sequence
l = UserList(['1', '2'])
self.f.writelines(l)
self.f.close()
self.f = open(TESTFN, 'rb')
buf = self.f.read()
self.assertEquals(buf, '12')
def testWritelinesIntegers(self):
# verify writelines with integers
self.assertRaises(TypeError, self.f.writelines, [1, 2, 3])
def testWritelinesIntegersUserList(self):
# verify writelines with integers in UserList
l = UserList([1,2,3])
self.assertRaises(TypeError, self.f.writelines, l)
def testWritelinesNonString(self):
# verify writelines with non-string object
class NonString:
pass
self.assertRaises(TypeError, self.f.writelines,
[NonString(), NonString()])
def testRepr(self):
# verify repr works
self.assert_(repr(self.f).startswith("<open file '" + TESTFN))
def testErrors(self):
f = self.f
self.assertEquals(f.name, TESTFN)
self.assert_(not f.isatty())
self.assert_(not f.closed)
self.assertRaises(TypeError, f.readinto, "")
f.close()
self.assert_(f.closed)
def testMethods(self):
methods = ['fileno', 'flush', 'isatty', 'next', 'read', 'readinto',
'readline', 'readlines', 'seek', 'tell', 'truncate',
'write', 'xreadlines', '__iter__']
if sys.platform.startswith('atheos'):
methods.remove('truncate')
# __exit__ should close the file
self.f.__exit__(None, None, None)
self.assert_(self.f.closed)
for methodname in methods:
method = getattr(self.f, methodname)
# should raise on closed file
self.assertRaises(ValueError, method)
self.assertRaises(ValueError, self.f.writelines, [])
# file is closed, __exit__ shouldn't do anything
self.assertEquals(self.f.__exit__(None, None, None), None)
# it must also return None if an exception was given
try:
1/0
except:
self.assertEquals(self.f.__exit__(*sys.exc_info()), None)
def testReadWhenWriting(self):
self.assertRaises(IOError, self.f.read)
class OtherFileTests(unittest.TestCase):
def testOpenDir(self):
this_dir = os.path.dirname(__file__)
for mode in (None, "w"):
try:
if mode:
f = open(this_dir, mode)
else:
f = open(this_dir)
except IOError as e:
self.assertEqual(e.filename, this_dir)
else:
self.fail("opening a directory didn't raise an IOError")
def testModeStrings(self):
# check invalid mode strings
for mode in ("", "aU", "wU+"):
try:
f = open(TESTFN, mode)
except ValueError:
pass
else:
f.close()
self.fail('%r is an invalid file mode' % mode)
# Some invalid modes fail on Windows, but pass on Unix
# Issue3965: avoid a crash on Windows when filename is unicode
for name in (TESTFN, unicode(TESTFN), unicode(TESTFN + '\t')):
try:
f = open(name, "rr")
except (IOError, ValueError):
pass
else:
f.close()
def testStdin(self):
# This causes the interpreter to exit on OSF1 v5.1.
if sys.platform != 'osf1V5':
self.assertRaises(IOError, sys.stdin.seek, -1)
else:
print >>sys.__stdout__, (
' Skipping sys.stdin.seek(-1), it may crash the interpreter.'
' Test manually.')
self.assertRaises(IOError, sys.stdin.truncate)
def testUnicodeOpen(self):
# verify repr works for unicode too
f = open(unicode(TESTFN), "w")
self.assert_(repr(f).startswith("<open file u'" + TESTFN))
f.close()
os.unlink(TESTFN)
def testBadModeArgument(self):
# verify that we get a sensible error message for bad mode argument
bad_mode = "qwerty"
try:
f = open(TESTFN, bad_mode)
except ValueError, msg:
if msg[0] != 0:
s = str(msg)
if s.find(TESTFN) != -1 or s.find(bad_mode) == -1:
self.fail("bad error message for invalid mode: %s" % s)
# if msg[0] == 0, we're probably on Windows where there may be
# no obvious way to discover why open() failed.
else:
f.close()
self.fail("no error for invalid mode: %s" % bad_mode)
def testSetBufferSize(self):
# make sure that explicitly setting the buffer size doesn't cause
# misbehaviour especially with repeated close() calls
for s in (-1, 0, 1, 512):
try:
f = open(TESTFN, 'w', s)
f.write(str(s))
f.close()
f.close()
f = open(TESTFN, 'r', s)
d = int(f.read())
f.close()
f.close()
except IOError, msg:
self.fail('error setting buffer size %d: %s' % (s, str(msg)))
self.assertEquals(d, s)
def testTruncateOnWindows(self):
os.unlink(TESTFN)
def bug801631():
# SF bug <http://www.python.org/sf/801631>
# "file.truncate fault on windows"
f = open(TESTFN, 'wb')
f.write('12345678901') # 11 bytes
f.close()
f = open(TESTFN,'rb+')
data = f.read(5)
if data != '12345':
self.fail("Read on file opened for update failed %r" % data)
if f.tell() != 5:
self.fail("File pos after read wrong %d" % f.tell())
f.truncate()
if f.tell() != 5:
self.fail("File pos after ftruncate wrong %d" % f.tell())
f.close()
size = os.path.getsize(TESTFN)
if size != 5:
self.fail("File size after ftruncate wrong %d" % size)
try:
bug801631()
finally:
os.unlink(TESTFN)
def testIteration(self):
# Test the complex interaction when mixing file-iteration and the
# various read* methods. Ostensibly, the mixture could just be tested
# to work when it should work according to the Python language,
# instead of fail when it should fail according to the current CPython
# implementation. People don't always program Python the way they
# should, though, and the implemenation might change in subtle ways,
# so we explicitly test for errors, too; the test will just have to
# be updated when the implementation changes.
dataoffset = 16384
filler = "ham\n"
assert not dataoffset % len(filler), \
"dataoffset must be multiple of len(filler)"
nchunks = dataoffset // len(filler)
testlines = [
"spam, spam and eggs\n",
"eggs, spam, ham and spam\n",
"saussages, spam, spam and eggs\n",
"spam, ham, spam and eggs\n",
"spam, spam, spam, spam, spam, ham, spam\n",
"wonderful spaaaaaam.\n"
]
methods = [("readline", ()), ("read", ()), ("readlines", ()),
("readinto", (array("c", " "*100),))]
try:
# Prepare the testfile
bag = open(TESTFN, "w")
bag.write(filler * nchunks)
bag.writelines(testlines)
bag.close()
# Test for appropriate errors mixing read* and iteration
for methodname, args in methods:
f = open(TESTFN)
if f.next() != filler:
self.fail, "Broken testfile"
meth = getattr(f, methodname)
try:
meth(*args)
except ValueError:
pass
else:
self.fail("%s%r after next() didn't raise ValueError" %
(methodname, args))
f.close()
# Test to see if harmless (by accident) mixing of read* and
# iteration still works. This depends on the size of the internal
# iteration buffer (currently 8192,) but we can test it in a
# flexible manner. Each line in the bag o' ham is 4 bytes
# ("h", "a", "m", "\n"), so 4096 lines of that should get us
# exactly on the buffer boundary for any power-of-2 buffersize
# between 4 and 16384 (inclusive).
f = open(TESTFN)
for i in range(nchunks):
f.next()
testline = testlines.pop(0)
try:
line = f.readline()
except ValueError:
self.fail("readline() after next() with supposedly empty "
"iteration-buffer failed anyway")
if line != testline:
self.fail("readline() after next() with empty buffer "
"failed. Got %r, expected %r" % (line, testline))
testline = testlines.pop(0)
buf = array("c", "\x00" * len(testline))
try:
f.readinto(buf)
except ValueError:
self.fail("readinto() after next() with supposedly empty "
"iteration-buffer failed anyway")
line = buf.tostring()
if line != testline:
self.fail("readinto() after next() with empty buffer "
"failed. Got %r, expected %r" % (line, testline))
testline = testlines.pop(0)
try:
line = f.read(len(testline))
except ValueError:
self.fail("read() after next() with supposedly empty "
"iteration-buffer failed anyway")
if line != testline:
self.fail("read() after next() with empty buffer "
"failed. Got %r, expected %r" % (line, testline))
try:
lines = f.readlines()
except ValueError:
self.fail("readlines() after next() with supposedly empty "
"iteration-buffer failed anyway")
if lines != testlines:
self.fail("readlines() after next() with empty buffer "
"failed. Got %r, expected %r" % (line, testline))
# Reading after iteration hit EOF shouldn't hurt either
f = open(TESTFN)
try:
for line in f:
pass
try:
f.readline()
f.readinto(buf)
f.read()
f.readlines()
except ValueError:
self.fail("read* failed after next() consumed file")
finally:
f.close()
finally:
os.unlink(TESTFN)
class FileSubclassTests(unittest.TestCase):
def testExit(self):
# test that exiting with context calls subclass' close
class C(file):
def __init__(self, *args):
self.subclass_closed = False
file.__init__(self, *args)
def close(self):
self.subclass_closed = True
file.close(self)
with C(TESTFN, 'w') as f:
pass
self.failUnless(f.subclass_closed)
class FileThreadingTests(unittest.TestCase):
# These tests check the ability to call various methods of file objects
# (including close()) concurrently without crashing the Python interpreter.
# See #815646, #595601
def setUp(self):
self.f = None
self.filename = TESTFN
with open(self.filename, "w") as f:
f.write("\n".join("0123456789"))
self._count_lock = threading.Lock()
self.close_count = 0
self.close_success_count = 0
def tearDown(self):
if self.f:
try:
self.f.close()
except (EnvironmentError, ValueError):
pass
try:
os.remove(self.filename)
except EnvironmentError:
pass
def _create_file(self):
self.f = open(self.filename, "w+")
def _close_file(self):
with self._count_lock:
self.close_count += 1
self.f.close()
with self._count_lock:
self.close_success_count += 1
def _close_and_reopen_file(self):
self._close_file()
# if close raises an exception thats fine, self.f remains valid so
# we don't need to reopen.
self._create_file()
def _run_workers(self, func, nb_workers, duration=0.2):
with self._count_lock:
self.close_count = 0
self.close_success_count = 0
self.do_continue = True
threads = []
try:
for i in range(nb_workers):
t = threading.Thread(target=func)
t.start()
threads.append(t)
for _ in xrange(100):
time.sleep(duration/100)
with self._count_lock:
if self.close_count-self.close_success_count > nb_workers+1:
if test_support.verbose:
print 'Q',
break
time.sleep(duration)
finally:
self.do_continue = False
for t in threads:
t.join()
def _test_close_open_io(self, io_func, nb_workers=5):
def worker():
self._create_file()
funcs = itertools.cycle((
lambda: io_func(),
lambda: self._close_and_reopen_file(),
))
for f in funcs:
if not self.do_continue:
break
try:
f()
except (IOError, ValueError):
pass
self._run_workers(worker, nb_workers)
if test_support.verbose:
# Useful verbose statistics when tuning this test to take
# less time to run but still ensuring that its still useful.
#
# the percent of close calls that raised an error
percent = 100. - 100.*self.close_success_count/self.close_count
print self.close_count, ('%.4f ' % percent),
def test_close_open(self):
def io_func():
pass
self._test_close_open_io(io_func)
def test_close_open_flush(self):
def io_func():
self.f.flush()
self._test_close_open_io(io_func)
def test_close_open_iter(self):
def io_func():
list(iter(self.f))
self._test_close_open_io(io_func)
def test_close_open_isatty(self):
def io_func():
self.f.isatty()
self._test_close_open_io(io_func)
def test_close_open_print(self):
def io_func():
print >> self.f, ''
self._test_close_open_io(io_func)
def test_close_open_read(self):
def io_func():
self.f.read(0)
self._test_close_open_io(io_func)
def test_close_open_readinto(self):
def io_func():
a = array('c', 'xxxxx')
self.f.readinto(a)
self._test_close_open_io(io_func)
def test_close_open_readline(self):
def io_func():
self.f.readline()
self._test_close_open_io(io_func)
def test_close_open_readlines(self):
def io_func():
self.f.readlines()
self._test_close_open_io(io_func)
def test_close_open_seek(self):
def io_func():
self.f.seek(0, 0)
self._test_close_open_io(io_func)
def test_close_open_tell(self):
def io_func():
self.f.tell()
self._test_close_open_io(io_func)
def test_close_open_truncate(self):
def io_func():
self.f.truncate()
self._test_close_open_io(io_func)
def test_close_open_write(self):
def io_func():
self.f.write('')
self._test_close_open_io(io_func)
def test_close_open_writelines(self):
def io_func():
self.f.writelines('')
self._test_close_open_io(io_func)
class StdoutTests(unittest.TestCase):
def test_move_stdout_on_write(self):
# Issue 3242: sys.stdout can be replaced (and freed) during a
# print statement; prevent a segfault in this case
save_stdout = sys.stdout
class File:
def write(self, data):
if '\n' in data:
sys.stdout = save_stdout
try:
sys.stdout = File()
print "some text"
finally:
sys.stdout = save_stdout
def test_del_stdout_before_print(self):
# Issue 4597: 'print' with no argument wasn't reporting when
# sys.stdout was deleted.
save_stdout = sys.stdout
del sys.stdout
try:
print
except RuntimeError as e:
self.assertEquals(str(e), "lost sys.stdout")
else:
self.fail("Expected RuntimeError")
finally:
sys.stdout = save_stdout
def test_main():
# Historically, these tests have been sloppy about removing TESTFN.
# So get rid of it no matter what.
try:
run_unittest(AutoFileTests, OtherFileTests, FileSubclassTests,
FileThreadingTests, StdoutTests)
finally:
if os.path.exists(TESTFN):
os.unlink(TESTFN)
if __name__ == '__main__':
test_main()