Unordered equality test of JSON data

jsoneq.py

"""Convert JSON to an immutable representation so that equality can be tested
without regard for order."""
import json


class decoder(json.JSONDecoder):
    # http://stackoverflow.com/questions/10885238/python-change-list-type-for-json-decoding
    def __init__(self, list_type=list, **kwargs):
        json.JSONDecoder.__init__(self, **kwargs)
        # Use the custom JSONArray
        self.parse_array = self.JSONArray
        # Use the python implemenation of the scanner
        self.scan_once = json.scanner.py_make_scanner(self)
        self.list_type = list_type

    def JSONArray(self, s_and_end, scan_once, **kwargs):
        values, end = json.decoder.JSONArray(s_and_end, scan_once, **kwargs)
        return self.list_type(values), end


class JsonSetEncoder(json.JSONEncoder):
    """Convert sets to lists for JSON encoding."""
    def default(self, obj):  # pylint: disable=method-hidden
        """Do conversion."""
        if isinstance(obj, frozenset):
            result = list(obj)
            if result and isinstance(result[0], tuple) and len(result[0]) == 2:
                return dict(result)
            return result
        return json.JSONEncoder.default(self, obj)


def itemset(d):
    """Convert dictionary to set of tuples."""
    return frozenset(d.items())


answerA = """{"answer": {"selections": [[{"start":0, "end":5, "extent":
    "Dalla", "word_index":0}], [{"start":0, "end":11, "extent":"provenivano",
    "word_index":2}], [{"start":0,"end":6,"word_index":3,"extent":"strani"},
    {"start":0,"end":6,"extent":"rumori","word_index":4}]]}}"""

answerB = """{"answer":{"selections":[[{"start":0,"end":11,"extent":
    "provenivano","word_index":2}],[{"start":0,"end":5,"extent":"Dalla",
    "word_index":0}],[{"start":0,"end":6,"word_index":3,"extent":"strani"},
    {"start":0,"end":6,"extent":"rumori","word_index":4}]]}}"""

jsonA = json.loads(answerA)
jsonB = json.loads(answerB)
print jsonA == jsonB

jsonA = json.loads(answerA, cls=decoder,
        list_type=frozenset, object_hook=itemset)
jsonB = json.loads(answerB, cls=decoder,
        list_type=frozenset, object_hook=itemset)
print jsonA == jsonB
print jsonA
print jsonB

print json.dumps(jsonA, cls=JsonSetEncoder, indent=2)