How to assert JSON equality in python-behave with diffs on failing tests?

Question

How do I assert JSON equality in python-behave and get a diff as output when assertion fails?

In Ruby I use: https://github.com/collectiveidea/json_spec , so I am basically looking for similar functionality in Python.

With a normal assert statement the output is very unhelpful.

Answer 1

I needed a similar functionality a while back. The easiest way I found was to use https://github.com/ChannelIQ/jsoncompare. You can install it with:

$ pip install jsoncompare

Then in your step code you can make an assert like this:

from jsoncompare import jsoncompare

if jsoncompare.are_same(json1, json2):
    assert True
else:
    print (jsoncompare.are_same(json1, json2))
    assert False 

By default, behave does not display print statements unless there is a failure, you must make the test fail in order to get the diff output to display.