Python's stdlib json.dumps and Flask's jsonify render JSON slightly differently

test_different_json_dumps.py

import json

import flask
from hamcrest import assert_that, is_


"""
json.dumps, by default, will include a bit of whitespace, using default
separators (', ', ': ') for item_separator and key_separator, respectively.
Flask defaults to a slightly more compact representation, using (',', ':')
as its separators. Depending on your tests, this could come up, and you
might wonder why rendering to JSON sometimes appears with spaces and
sometimes doesn't. This might be why.
"""

dict_ = {'everything': 42, 'blarney': 'stone'}
list_ = [1, 2, "buckle", "my", "shoe"]


def test_json_dumps():
    json_dict = json.dumps(dict_, sort_keys=True)
    json_list = json.dumps(list_)

    assert_that(json_dict, is_('{"blarney": "stone", "everything": 42}'))
    assert_that(json_list, is_('[1, 2, "buckle", "my", "shoe"]'))


def test_flask_jsonify():
    flask_app = flask.Flask(__name__)
    with flask_app.app_context():
        flask_json_dict = flask.jsonify(dict_)
        flask_json_list = flask.jsonify(list_)

        assert_that(
            flask_json_dict.get_data(as_text=True).strip(),
            is_('{"blarney":"stone","everything":42}')
        )
        assert_that(
            flask_json_list.get_data(as_text=True).strip(),
            is_('[1,2,"buckle","my","shoe"]')
        )