from __future__ import print_function

import unittest
import inspect

import wrapt

from .decorators import passthru_function_decorator

def function(arg):
    '''documentation'''
    return arg

original = function

@passthru_function_decorator
def function(arg):
    '''documentation'''
    return arg

class TestNamingFunction(unittest.TestCase):

    def test_object_name(self):
        # Test preservation of function __name__ attribute.

        self.assertEqual(function.__name__, original.__name__)

    def test_object_qualname(self):
        # Test preservation of function __qualname__ attribute.

        try:
            __qualname__ = original.__qualname__
        except AttributeError:
            pass
        else:
            self.assertEqual(function.__qualname__, __qualname__)

    def test_module_name(self):
       # Test preservation of function __module__ attribute.

        self.assertEqual(function.__module__, __name__)

    def test_doc_string(self):
        # Test preservation of function __doc__ attribute.

        self.assertEqual(function.__doc__, original.__doc__)

    def test_argspec(self):
        # Test preservation of function argument specification.

        original_argspec = inspect.getargspec(original)
        function_argspec = inspect.getargspec(function)
        self.assertEqual(original_argspec, function_argspec)

    def test_isinstance(self):
        # Test preservation of isinstance() checks.

        self.assertTrue(isinstance(function, type(original)))

class TestCallingFunction(unittest.TestCase):

    def test_call_function(self):
        _args = (1, 2)
        _kwargs = { 'one': 1, 'two': 2 }

        @wrapt.function_decorator
        def _decorator(wrapped, args, kwargs):
            return wrapped(*args, **kwargs)

        @_decorator
        def _function(*args, **kwargs):
            return args, kwargs

        result = _function(*_args, **_kwargs)

        self.assertEqual(result, (_args, _kwargs))