def ReopenForRead(self):
try:
self.f.close()
except IOError:
pass
self.f = _FileIO(TESTFN, 'r')
os.close(self.f.fileno())
return self.f
python类FileIO()的实例源码
def testModeStrings(self):
# test that the mode attribute is correct for various mode strings
# given as init args
try:
for modes in [('w', 'wb'), ('wb', 'wb'), ('wb+', 'rb+'),
('w+b', 'rb+'), ('a', 'ab'), ('ab', 'ab'),
('ab+', 'ab+'), ('a+b', 'ab+'), ('r', 'rb'),
('rb', 'rb'), ('rb+', 'rb+'), ('r+b', 'rb+')]:
# read modes are last so that TESTFN will exist first
with _FileIO(TESTFN, modes[0]) as f:
self.assertEqual(f.mode, modes[1])
finally:
if os.path.exists(TESTFN):
os.unlink(TESTFN)
def testUnicodeOpen(self):
# verify repr works for unicode too
f = _FileIO(str(TESTFN), "w")
f.close()
os.unlink(TESTFN)
def testBytesOpen(self):
# Opening a bytes filename
try:
fn = TESTFN.encode("ascii")
except UnicodeEncodeError:
self.skipTest('could not encode %r to ascii' % TESTFN)
f = _FileIO(fn, "w")
try:
f.write(b"abc")
f.close()
with open(TESTFN, "rb") as f:
self.assertEqual(f.read(), b"abc")
finally:
os.unlink(TESTFN)
def testConstructorHandlesNULChars(self):
fn_with_NUL = 'foo\0bar'
self.assertRaises(TypeError, _FileIO, fn_with_NUL, 'w')
self.assertRaises(TypeError, _FileIO, fn_with_NUL.encode('ascii'), 'w')
def testInvalidFd(self):
self.assertRaises(ValueError, _FileIO, -10)
self.assertRaises(OSError, _FileIO, make_bad_fd())
if sys.platform == 'win32':
import msvcrt
self.assertRaises(IOError, msvcrt.get_osfhandle, make_bad_fd())
def testBadModeArgument(self):
# verify that we get a sensible error message for bad mode argument
bad_mode = "qwerty"
try:
f = _FileIO(TESTFN, bad_mode)
except ValueError as msg:
if msg.args[0] != 0:
s = str(msg)
if TESTFN in s or bad_mode not in s:
self.fail("bad error message for invalid mode: %s" % s)
# if msg.args[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 testTruncate(self):
f = _FileIO(TESTFN, 'w')
f.write(bytes(bytearray(range(10))))
self.assertEqual(f.tell(), 10)
f.truncate(5)
self.assertEqual(f.tell(), 10)
self.assertEqual(f.seek(0, os.SEEK_END), 5)
f.truncate(15)
self.assertEqual(f.tell(), 5)
self.assertEqual(f.seek(0, os.SEEK_END), 15)
f.close()
def testTruncateOnWindows(self):
def bug801631():
# SF bug <http://www.python.org/sf/801631>
# "file.truncate fault on windows"
f = _FileIO(TESTFN, 'w')
f.write(bytes(range(11)))
f.close()
f = _FileIO(TESTFN,'r+')
data = f.read(5)
if data != bytes(range(5)):
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 testInvalidInit(self):
self.assertRaises(TypeError, _FileIO, "1", 0, 0)
def testWarnings(self):
with check_warnings(quiet=True) as w:
self.assertEqual(w.warnings, [])
self.assertRaises(TypeError, _FileIO, [])
self.assertEqual(w.warnings, [])
self.assertRaises(ValueError, _FileIO, "/some/invalid/name", "rt")
self.assertEqual(w.warnings, [])
def testUnclosedFDOnException(self):
class MyException(Exception): pass
class MyFileIO(_FileIO):
def __setattr__(self, name, value):
if name == "name":
raise MyException("blocked setting name")
return super(MyFileIO, self).__setattr__(name, value)
fd = os.open(__file__, os.O_RDONLY)
self.assertRaises(MyException, MyFileIO, fd)
os.close(fd) # should not raise OSError(EBADF)
def setUp(self):
self.f = _FileIO(TESTFN, 'w')
def testReadinto(self):
# verify readinto
self.f.write(b"\x01\x02")
self.f.close()
a = array(b'b', b'x'*10)
self.f = _FileIO(TESTFN, 'r')
n = self.f.readinto(a)
self.assertEqual(array(b'b', [1, 2]), a[:n])
def testWritelinesList(self):
l = [b'123', b'456']
self.f.writelines(l)
self.f.close()
self.f = _FileIO(TESTFN, 'rb')
buf = self.f.read()
self.assertEqual(buf, b'123456')
def testWritelinesUserList(self):
l = UserList([b'123', b'456'])
self.f.writelines(l)
self.f.close()
self.f = _FileIO(TESTFN, 'rb')
buf = self.f.read()
self.assertEqual(buf, b'123456')
def test_none_args(self):
self.f.write(b"hi\nbye\nabc")
self.f.close()
self.f = _FileIO(TESTFN, 'r')
self.assertEqual(self.f.read(None), b"hi\nbye\nabc")
self.f.seek(0)
self.assertEqual(self.f.readline(None), b"hi\n")
self.assertEqual(self.f.readlines(None), [b"bye\n", b"abc"])
def testOpendir(self):
# Issue 3703: opening a directory should fill the errno
# Windows always returns "[Errno 13]: Permission denied
# Unix calls dircheck() and returns "[Errno 21]: Is a directory"
try:
_FileIO('.', 'r')
except IOError as e:
self.assertNotEqual(e.errno, 0)
self.assertEqual(e.filename, ".")
else:
self.fail("Should have raised IOError")
def testOpenDirFD(self):
fd = os.open('.', os.O_RDONLY)
with self.assertRaises(IOError) as cm:
_FileIO(fd, 'r')
os.close(fd)
self.assertEqual(cm.exception.errno, errno.EISDIR)
#A set of functions testing that we get expected behaviour if someone has
#manually closed the internal file descriptor. First, a decorator:
def ReopenForRead(self):
try:
self.f.close()
except IOError:
pass
self.f = _FileIO(TESTFN, 'r')
os.close(self.f.fileno())
return self.f