import json

def round_trip_test(obj):

# serde_json and Python's json module produce slightly differently spaced

# output; direct string comparison can't pass on both so we use this as a

# proxy

assert obj == json.loads(json.dumps(obj))

assert '"string"' == json.dumps("string")

assert "1" == json.dumps(1)

assert "1.0" == json.dumps(1.0)

assert "true" == json.dumps(True)

assert "false" == json.dumps(False)

assert 'null' == json.dumps(None)

assert '[]' == json.dumps([])

assert '[1]' == json.dumps([1])

assert '[[1]]' == json.dumps([[1]])

round_trip_test([1, "string", 1.0, True])

assert '[]' == json.dumps(())

assert '[1]' == json.dumps((1,))

assert '[[1]]' == json.dumps(((1,),))

# tuples don't round-trip through json

assert [1, "string", 1.0, True] == json.loads(json.dumps((1, "string", 1.0, True)))

assert '{}' == json.dumps({})

# TODO: uncomment once dict comparison is implemented

# round_trip_test({'a': 'b'})

assert 1 == json.loads("1")

assert -1 == json.loads("-1")

assert 1.0 == json.loads("1.0")

# TODO: uncomment once negative floats are implemented

# assert -1.0 == json.loads("-1.0")

assert "str" == json.loads('"str"')

assert True is json.loads('true')

assert False is json.loads('false')

assert None is json.loads('null')

assert [] == json.loads('[]')

assert ['a'] == json.loads('["a"]')

assert [['a'], 'b'] == json.loads('[["a"], "b"]')

class String(str): pass

assert "string" == json.loads(String('"string"'))

assert '"string"' == json.dumps(String("string"))

# TODO: Uncomment and test once int/float construction is supported

# class Int(int): pass

# class Float(float): pass

# TODO: Uncomment and test once sequence/dict subclasses are supported by

# json.dumps

# class List(list): pass

# class Tuple(tuple): pass

# class Dict(dict): pass