Problems testing PaaSIO exercise

Programming Python
1

I am having trouble with testing the PaaSIO exercise. I’m obviously missing something important. When I run the tests, I get a whole lot of failures/errors like this:

_________________ PaasioTest.test_meteredfile_context_manager __________________

self = <paasio_test.PaasioTest testMethod=test_meteredfile_context_manager>
super_mock = <SuperMock at 0x74f434541d60 with mock object: <NonCallableMagicMock id='128592190498832'>>

    @patch("paasio.super", create=True, new_callable=SuperMock)
    def test_meteredfile_context_manager(self, super_mock):
        wrapped = MockFile(ZEN)
        mock = NonCallableMagicMock(wraps=wrapped, autospec=True)
        mock.__exit__.side_effect = wrapped.__exit__
        super_mock.mock_object = mock
        with MeteredFile() as file:
            self.assertEqual(1, super_mock.init_called)
            self.assertFalse(mock.__enter__.called)
>           file.read()

paasio_test.py:224: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

self = <MeteredFile>, size = -1

    def read(self, size=-1):
        if self._closed:
            raise ValueError("I/O operation on closed file.")
    
>       data = super.read(size)
E       AttributeError: 'SuperMock' object has no attribute 'read'

paasio.py:31: AttributeError

I don’t get why super.read() (and other super calls) get this error. If I’m not supposed to write super.read(), how do I call the superclass’s read() method?

2

Could you share your entire code?

3

It’s not complete yet…

import io


class MeteredFile(io.BufferedRandom):
    """Implement using a subclassing model."""

    def __init__(self, *args, **kwargs):
        super.__init__(*args, **kwargs)
        self._read_bytes = 0
        self._read_ops = 0
        self._write_bytes = 0
        self._write_ops = 0
        self._closed = False

    def __enter__(self):
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        self._closed = True

    def __iter__(self):
        pass

    def __next__(self):
        pass

    def read(self, size=-1):
        if self._closed:
            raise ValueError("I/O operation on closed file.")
        
        data = super.read(size)
        self._read_bytes += len(data)
        self._read_ops += 1
        return data

    @property
    def read_bytes(self):
        return self._read_bytes

    @property
    def read_ops(self):
        return self._read_ops

    def write(self, b):
        if self._closed:
            raise ValueError("I/O operation on closed file.")
        
        super.write(b)
        self._write_bytes += len(b)
        self._write_ops += 1

    @property
    def write_bytes(self):
        return self._write_bytes

    @property
    def write_ops(self):
        return self._write_ops


class MeteredSocket:
    """Implement using a delegation model."""

    def __init__(self, socket):
        self._socket = socket
        self._recv_size = 0
        self._recv_ops = 0
        self._send_size = 0
        self._send_ops = 0
        self._closed = False

    def __enter__(self):
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        self._closed = True

    def recv(self, bufsize, flags=0):
        if self._closed:
            raise OSError("Bad file descriptor")
        
        if bufsize is None:
            raise TypeError("'NoneType' is not valid, must be an integer")

        data = self._socket.recv(bufsize, flags=flags)
        self._recv_size += bufsize
        self._recv_ops += 1
        return data

    @property
    def recv_bytes(self):
        return self._recv_size

    @property
    def recv_ops(self):
        return self._recv_ops

    def send(self, data, flags=0):
        if self._closed:
            raise OSError("Bad file descriptor")
        
        self._socket.send(data, flag=flags)
        self._send_size += len(data)
        self._send_ops += 1

    @property
    def send_bytes(self):
        return self._send_size

    @property
    def send_ops(self):
        return self._send_ops
4

super.read() and super.write() should be super().read() and super().write().

5

Thank you! I was going nuts.