Python test.support.TESTFN Examples

def setUpClass(cls):
        def chunks(total, step):
            assert total >= step
            while total > step:
                yield step
                total -= step
            if total:
                yield total

        chunk = b"".join([random.choice(string.ascii_letters).encode()
                          for i in range(cls.BUFSIZE)])
        with open(support.TESTFN, 'wb') as f:
            for csize in chunks(cls.FILESIZE, cls.BUFSIZE):
                f.write(chunk)
        with open(support.TESTFN, 'rb') as f:
            cls.FILEDATA = f.read()
            assert len(cls.FILEDATA) == cls.FILESIZE 

def test_telling(self):
        f = self.open(support.TESTFN, "w+", encoding="utf-8")
        p0 = f.tell()
        f.write("\xff\n")
        p1 = f.tell()
        f.write("\xff\n")
        p2 = f.tell()
        f.seek(0)
        self.assertEqual(f.tell(), p0)
        self.assertEqual(f.readline(), "\xff\n")
        self.assertEqual(f.tell(), p1)
        self.assertEqual(f.readline(), "\xff\n")
        self.assertEqual(f.tell(), p2)
        f.seek(0)
        for line in f:
            self.assertEqual(line, "\xff\n")
            self.assertRaises(OSError, f.tell)
        self.assertEqual(f.tell(), p2)
        f.close() 

def test_rmtree(self):
        dirpath = support.TESTFN + 'd'
        subdirpath = os.path.join(dirpath, 'subdir')
        os.mkdir(dirpath)
        os.mkdir(subdirpath)
        support.rmtree(dirpath)
        self.assertFalse(os.path.exists(dirpath))
        with support.swap_attr(support, 'verbose', 0):
            support.rmtree(dirpath)

        os.mkdir(dirpath)
        os.mkdir(subdirpath)
        os.chmod(dirpath, stat.S_IRUSR|stat.S_IXUSR)
        with support.swap_attr(support, 'verbose', 0):
            support.rmtree(dirpath)
        self.assertFalse(os.path.exists(dirpath))

        os.mkdir(dirpath)
        os.mkdir(subdirpath)
        os.chmod(dirpath, 0)
        with support.swap_attr(support, 'verbose', 0):
            support.rmtree(dirpath)
        self.assertFalse(os.path.exists(dirpath)) 

def test_seeking(self):
        chunk_size = _default_chunk_size()
        prefix_size = chunk_size - 2
        u_prefix = "a" * prefix_size
        prefix = bytes(u_prefix.encode("utf-8"))
        self.assertEqual(len(u_prefix), len(prefix))
        u_suffix = "\u8888\n"
        suffix = bytes(u_suffix.encode("utf-8"))
        line = prefix + suffix
        with self.open(support.TESTFN, "wb") as f:
            f.write(line*2)
        with self.open(support.TESTFN, "r", encoding="utf-8") as f:
            s = f.read(prefix_size)
            self.assertEqual(s, str(prefix, "ascii"))
            self.assertEqual(f.tell(), prefix_size)
            self.assertEqual(f.readline(), u_suffix) 

def test_with_open(self):
        for bufsize in (0, 1, 100):
            f = None
            with self.open(support.TESTFN, "wb", bufsize) as f:
                f.write(b"xxx")
            self.assertEqual(f.closed, True)
            f = None
            try:
                with self.open(support.TESTFN, "wb", bufsize) as f:
                    1/0
            except ZeroDivisionError:
                self.assertEqual(f.closed, True)
            else:
                self.fail("1/0 didn't raise an exception")

    # issue 5008 

def test_flush_error_on_close(self):
        # raw file
        # Issue #5700: io.FileIO calls flush() after file closed
        self.check_flush_error_on_close(support.TESTFN, 'wb', buffering=0)
        fd = os.open(support.TESTFN, os.O_WRONLY|os.O_CREAT)
        self.check_flush_error_on_close(fd, 'wb', buffering=0)
        fd = os.open(support.TESTFN, os.O_WRONLY|os.O_CREAT)
        self.check_flush_error_on_close(fd, 'wb', buffering=0, closefd=False)
        os.close(fd)
        # buffered io
        self.check_flush_error_on_close(support.TESTFN, 'wb')
        fd = os.open(support.TESTFN, os.O_WRONLY|os.O_CREAT)
        self.check_flush_error_on_close(fd, 'wb')
        fd = os.open(support.TESTFN, os.O_WRONLY|os.O_CREAT)
        self.check_flush_error_on_close(fd, 'wb', closefd=False)
        os.close(fd)
        # text io
        self.check_flush_error_on_close(support.TESTFN, 'w')
        fd = os.open(support.TESTFN, os.O_WRONLY|os.O_CREAT)
        self.check_flush_error_on_close(fd, 'w')
        fd = os.open(support.TESTFN, os.O_WRONLY|os.O_CREAT)
        self.check_flush_error_on_close(fd, 'w', closefd=False)
        os.close(fd) 

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 = self.open(TESTFN, 'wb', s)
                f.write(str(s).encode("ascii"))
                f.close()
                f.close()
                f = self.open(TESTFN, 'rb', s)
                d = int(f.read().decode("ascii"))
                f.close()
                f.close()
            except IOError as msg:
                self.fail('error setting buffer size %d: %s' % (s, str(msg)))
            self.assertEqual(d, s) 

def test_invalid_operations(self):
        # Try writing on a file opened in read mode and vice-versa.
        exc = self.UnsupportedOperation
        for mode in ("w", "wb"):
            with self.open(support.TESTFN, mode) as fp:
                self.assertRaises(exc, fp.read)
                self.assertRaises(exc, fp.readline)
        with self.open(support.TESTFN, "wb", buffering=0) as fp:
            self.assertRaises(exc, fp.read)
            self.assertRaises(exc, fp.readline)
        with self.open(support.TESTFN, "rb", buffering=0) as fp:
            self.assertRaises(exc, fp.write, b"blah")
            self.assertRaises(exc, fp.writelines, [b"blah\n"])
        with self.open(support.TESTFN, "rb") as fp:
            self.assertRaises(exc, fp.write, b"blah")
            self.assertRaises(exc, fp.writelines, [b"blah\n"])
        with self.open(support.TESTFN, "r") as fp:
            self.assertRaises(exc, fp.write, "blah")
            self.assertRaises(exc, fp.writelines, ["blah\n"])
            # Non-zero seeking from current or end pos
            self.assertRaises(exc, fp.seek, 1, self.SEEK_CUR)
            self.assertRaises(exc, fp.seek, -1, self.SEEK_END) 

def test_sys_exit(self):
        # See Issue 13854
        if self.TYPE == 'threads':
            self.skipTest('test not appropriate for {}'.format(self.TYPE))

        testfn = support.TESTFN
        self.addCleanup(support.unlink, testfn)

        for reason, code in (([1, 2, 3], 1), ('ignore this', 1)):
            p = self.Process(target=self._test_sys_exit, args=(reason, testfn))
            p.daemon = True
            p.start()
            p.join(5)
            self.assertEqual(p.exitcode, code)

            with open(testfn, 'r') as f:
                self.assertEqual(f.read().rstrip(), str(reason))

        for reason in (True, False, 8):
            p = self.Process(target=sys.exit, args=(reason,))
            p.daemon = True
            p.start()
            p.join(5)
            self.assertEqual(p.exitcode, reason) 

def test_fd_transfer(self):
        if self.TYPE != 'processes':
            self.skipTest("only makes sense with processes")
        conn, child_conn = self.Pipe(duplex=True)

        p = self.Process(target=self._writefd, args=(child_conn, b"foo"))
        p.daemon = True
        p.start()
        self.addCleanup(support.unlink, support.TESTFN)
        with open(support.TESTFN, "wb") as f:
            fd = f.fileno()
            if msvcrt:
                fd = msvcrt.get_osfhandle(fd)
            reduction.send_handle(conn, fd, p.pid)
        p.join()
        with open(support.TESTFN, "rb") as f:
            self.assertEqual(f.read(), b"foo") 

def test_large_fd_transfer(self):
        # With fd > 256 (issue #11657)
        if self.TYPE != 'processes':
            self.skipTest("only makes sense with processes")
        conn, child_conn = self.Pipe(duplex=True)

        p = self.Process(target=self._writefd, args=(child_conn, b"bar", True))
        p.daemon = True
        p.start()
        self.addCleanup(support.unlink, support.TESTFN)
        with open(support.TESTFN, "wb") as f:
            fd = f.fileno()
            for newfd in range(256, MAXFD):
                if not self._is_fd_assigned(newfd):
                    break
            else:
                self.fail("could not find an unassigned large file descriptor")
            os.dup2(fd, newfd)
            try:
                reduction.send_handle(conn, newfd, p.pid)
            finally:
                os.close(newfd)
        p.join()
        with open(support.TESTFN, "rb") as f:
            self.assertEqual(f.read(), b"bar") 

def test_security(self):
        # This test is incomplete since we are normally not run as root and
        # therefore can't test the file ownership being wrong.
        d = support.TESTFN
        os.mkdir(d)
        self.addCleanup(support.rmtree, d)
        fn = os.path.join(d, '.netrc')
        with open(fn, 'wt') as f:
            f.write("""\
                machine foo.domain.com login bar password pass
                default login foo password pass
                """)
        with support.EnvironmentVarGuard() as environ:
            environ.set('HOME', d)
            os.chmod(fn, 0o600)
            nrc = netrc.netrc()
            self.assertEqual(nrc.hosts['foo.domain.com'],
                             ('bar', None, 'pass'))
            os.chmod(fn, 0o622)
            self.assertRaises(netrc.NetrcParseError, netrc.netrc) 

def test_errors(self):
        with open(support.TESTFN, 'rb') as file:
            with socket.socket(type=socket.SOCK_DGRAM) as s:
                meth = self.meth_from_sock(s)
                self.assertRaisesRegex(
                    ValueError, "SOCK_STREAM", meth, file)
        with open(support.TESTFN, 'rt') as file:
            with socket.socket() as s:
                meth = self.meth_from_sock(s)
                self.assertRaisesRegex(
                    ValueError, "binary mode", meth, file)
        with open(support.TESTFN, 'rb') as file:
            with socket.socket() as s:
                meth = self.meth_from_sock(s)
                self.assertRaisesRegex(TypeError, "positive integer",
                                       meth, file, count='2')
                self.assertRaisesRegex(TypeError, "positive integer",
                                       meth, file, count=0.1)
                self.assertRaisesRegex(ValueError, "positive integer",
                                       meth, file, count=0)
                self.assertRaisesRegex(ValueError, "positive integer",
                                       meth, file, count=-1) 

def test_command_packages_configfile(self):
        sys.argv.append("build")
        self.addCleanup(os.unlink, TESTFN)
        f = open(TESTFN, "w")
        try:
            print("[global]", file=f)
            print("command_packages = foo.bar, splat", file=f)
        finally:
            f.close()

        d = self.create_distribution([TESTFN])
        self.assertEqual(d.get_command_packages(),
                         ["distutils.command", "foo.bar", "splat"])

        # ensure command line overrides config:
        sys.argv[1:] = ["--command-packages", "spork", "build"]
        d = self.create_distribution([TESTFN])
        self.assertEqual(d.get_command_packages(),
                         ["distutils.command", "spork"])

        # Setting --command-packages to '' should cause the default to
        # be used even if a config file specified something else:
        sys.argv[1:] = ["--command-packages", "", "build"]
        d = self.create_distribution([TESTFN])
        self.assertEqual(d.get_command_packages(), ["distutils.command"]) 

def test_closefd(self):
        self.assertRaises(ValueError, self.open, support.TESTFN, 'w',
                          closefd=False) 

def test_truncate(self):
        # Truncate implicitly flushes the buffer.
        with self.open(support.TESTFN, self.write_mode, buffering=0) as raw:
            bufio = self.tp(raw, 8)
            bufio.write(b"abcdef")
            self.assertEqual(bufio.truncate(3), 3)
            self.assertEqual(bufio.tell(), 6)
        with self.open(support.TESTFN, "rb", buffering=0) as f:
            self.assertEqual(f.read(), b"abc") 

def test_garbage_collection(self):
        # C BufferedWriter objects are collected, and collecting them flushes
        # all data to disk.
        # The Python version has __del__, so it ends into gc.garbage instead
        with support.check_warnings(('', ResourceWarning)):
            rawio = self.FileIO(support.TESTFN, "w+b")
            f = self.tp(rawio)
            f.write(b"123xxx")
            f.x = f
            wr = weakref.ref(f)
            del f
            support.gc_collect()
        self.assertIsNone(wr(), wr)
        with self.open(support.TESTFN, "rb") as f:
            self.assertEqual(f.read(), b"123xxx") 

def test_read_closed(self):
        with self.open(support.TESTFN, "w") as f:
            f.write("egg\n")
        with self.open(support.TESTFN, "r") as f:
            file = self.open(f.fileno(), "r", closefd=False)
            self.assertEqual(file.read(), "egg\n")
            file.seek(0)
            file.close()
            self.assertRaises(ValueError, file.read) 

def tearDown(self):
        support.unlink(support.TESTFN) 

def setUp(self):
        support.unlink(support.TESTFN) 

def tearDown(self):
        support.unlink(support.TESTFN) 

def test_basic_io(self):
        for chunksize in (1, 2, 3, 4, 5, 15, 16, 17, 31, 32, 33, 63, 64, 65):
            for enc in "ascii", "latin-1", "utf-8" :# , "utf-16-be", "utf-16-le":
                f = self.open(support.TESTFN, "w+", encoding=enc)
                f._CHUNK_SIZE = chunksize
                self.assertEqual(f.write("abc"), 3)
                f.close()
                f = self.open(support.TESTFN, "r+", encoding=enc)
                f._CHUNK_SIZE = chunksize
                self.assertEqual(f.tell(), 0)
                self.assertEqual(f.read(), "abc")
                cookie = f.tell()
                self.assertEqual(f.seek(0), 0)
                self.assertEqual(f.read(None), "abc")
                f.seek(0)
                self.assertEqual(f.read(2), "ab")
                self.assertEqual(f.read(1), "c")
                self.assertEqual(f.read(1), "")
                self.assertEqual(f.read(), "")
                self.assertEqual(f.tell(), cookie)
                self.assertEqual(f.seek(0), 0)
                self.assertEqual(f.seek(0, 2), cookie)
                self.assertEqual(f.write("def"), 3)
                self.assertEqual(f.seek(cookie), cookie)
                self.assertEqual(f.read(), "def")
                if enc.startswith("utf"):
                    self.multi_line_test(f, enc)
                f.close() 

def _testWithTimeout(self):
        address = self.serv.getsockname()
        file = open(support.TESTFN, 'rb')
        with socket.create_connection(address, timeout=2) as sock, file as file:
            meth = self.meth_from_sock(sock)
            sent = meth(file)
            self.assertEqual(sent, self.FILESIZE) 

def _testNonBlocking(self):
        address = self.serv.getsockname()
        file = open(support.TESTFN, 'rb')
        with socket.create_connection(address) as sock, file as file:
            sock.setblocking(False)
            meth = self.meth_from_sock(sock)
            self.assertRaises(ValueError, meth, file)
            self.assertRaises(ValueError, sock.sendfile, file) 

def _testCountWithOffset(self):
        address = self.serv.getsockname()
        file = open(support.TESTFN, 'rb')
        with socket.create_connection(address, timeout=2) as sock, file as file:
            count = 100007
            meth = self.meth_from_sock(sock)
            sent = meth(file, offset=2007, count=count)
            self.assertEqual(sent, count)
            self.assertEqual(file.tell(), count + 2007) 

def _testCountSmall(self):
        address = self.serv.getsockname()
        file = open(support.TESTFN, 'rb')
        with socket.create_connection(address, timeout=2) as sock, file as file:
            count = 1
            meth = self.meth_from_sock(sock)
            sent = meth(file, count=count)
            self.assertEqual(sent, count)
            self.assertEqual(file.tell(), count) 

def _testCount(self):
        address = self.serv.getsockname()
        file = open(support.TESTFN, 'rb')
        with socket.create_connection(address, timeout=2) as sock, file as file:
            count = 5000007
            meth = self.meth_from_sock(sock)
            sent = meth(file, count=count)
            self.assertEqual(sent, count)
            self.assertEqual(file.tell(), count) 

def _testEmptyFileSend(self):
        address = self.serv.getsockname()
        filename = support.TESTFN + "2"
        with open(filename, 'wb'):
            self.addCleanup(support.unlink, filename)
        file = open(filename, 'rb')
        with socket.create_connection(address) as sock, file as file:
            meth = self.meth_from_sock(sock)
            sent = meth(file)
            self.assertEqual(sent, 0)
            self.assertEqual(file.tell(), 0) 

def _testRegularFile(self):
        address = self.serv.getsockname()
        file = open(support.TESTFN, 'rb')
        with socket.create_connection(address) as sock, file as file:
            meth = self.meth_from_sock(sock)
            sent = meth(file)
            self.assertEqual(sent, self.FILESIZE)
            self.assertEqual(file.tell(), self.FILESIZE) 

def test_garbage_collection(self):
        # C BufferedReader objects are collected.
        # The Python version has __del__, so it ends into gc.garbage instead
        with support.check_warnings(('', ResourceWarning)):
            rawio = self.FileIO(support.TESTFN, "w+b")
            f = self.tp(rawio)
            f.f = f
            wr = weakref.ref(f)
            del f
            support.gc_collect()
        self.assertIsNone(wr(), wr)