Clean up, remove compat with py < 3.6

[pyi2ncommon] / src / type_helpers.py

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# Copyright (c) 2016-2018 Intra2net AG <info@intra2net.com>

"""
Helpers for type checking and conversion, like `isstr(x)`, `is_file_obj(x)`

Some of these things used to be more complicated when python2 was still
around, so some functions are not that useful anymore.
"""

from io import IOBase


def isstr(var):
    """Alias for `isinstance(var, str)`."""
    return isinstance(var, str)


def is_str_or_byte(var):
    """Returns `True` for `str` and `bytes` objects."""
    return isinstance(var, (str, bytes))


def is_unicode(var):
    """Alias for `isinstance(var, str)`."""
    return isinstance(var, str)


def is_file_obj(var):
    """
    Determine whether given input is the result of 'open(file_name)'.

    Just checks whether given var is subclass of io.IOBase, which is also True
    for 'file-like objects' like StringIO.
    """
    return isinstance(var, IOBase)