def test_python_file_write():
buf = BytesIO()
f = io.PythonFileInterface(buf)
assert f.tell() == 0
s1 = b'enga\xc3\xb1ado'
s2 = b'foobar'
f.write(s1.decode('utf8'))
assert f.tell() == len(s1)
f.write(s2)
expected = s1 + s2
result = buf.getvalue()
assert result == expected
f.close()
def test_python_file_read():
data = b'some sample data'
buf = BytesIO(data)
f = io.PythonFileInterface(buf, mode='r')
assert f.size() == len(data)
assert f.tell() == 0
assert f.read(4) == b'some'
assert f.tell() == 4
f.seek(0)
assert f.tell() == 0
f.seek(5)
assert f.tell() == 5
assert f.read(50) == b'sample data'
f.close()
