Does pytest have an assertItemsEqual / assertCountEqual equivalent

Question

pytest does not provide an assertCountEqual, but we can just use unittest’s:

import unittest

def test_stuff():
    case = unittest.TestCase()
    a = [{'a': 1}, {'b': 2}]
    b = [{'b': 2}]
    case.assertCountEqual(a, b)

And the output is decent, too

$ py.test
============================= test session starts ==============================
platform linux -- Python 3.6.2, pytest-3.2.1, py-1.4.34, pluggy-0.4.0
rootdir: /home/they4kman/.virtualenvs/tmp-6626234b42fb350/src, inifile:
collected 1 item

test_stuff.py F

=================================== FAILURES ===================================
__________________________________ test_stuff __________________________________

    def test_stuff():
        case = unittest.TestCase()
        a = [{'a': 1}, {'b': 2}]
        b = [{'b': 2}]
>       case.assertCountEqual(a, b)

test_stuff.py:7:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
/usr/lib/python3.6/unittest/case.py:1182: in assertCountEqual
    self.fail(msg)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <unittest.case.TestCase testMethod=runTest>
msg = "Element counts were not equal:\nFirst has 1, Second has 0:  {'a': 1}"

    def fail(self, msg=None):
        """Fail immediately, with the given message."""
>       raise self.failureException(msg)
E       AssertionError: Element counts were not equal:
E       First has 1, Second has 0:  {'a': 1}

/usr/lib/python3.6/unittest/case.py:670: AssertionError
=========================== 1 failed in 0.07 seconds ==========================

Side note: the implementation of assertCountEqual includes a branch specifically for unhashable types, which does a bunch of bookkeeping and compares each item with every other item.

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