Deletion of dictionary key not shown

[PhilippVWC]

Hey. Thank you for your work on a handy cli tool to beautifully print json differences. It helps me a lot in my daily business.

Recently I discovered an unexpected behaviour.

The bash command line

jdiff -s explicit <(echo '{"a":1}') <(echo '{}')

outputs nothing.
I would expect it to yield

{"$delete": ["a"]}

The problem is caused by the following line:

jsondiff/jsondiff/cli.py

Line 36 in 31140ba

if not (parsed_first and parsed_second):

The expression

not parsed_second

wrongly evaluates to true, since parsed_second is an empty dictionary.

I suggest you to change the line to

    if parsed_first is None and parsed_second is None:

Can you do that or do you want me to create a pull request?

Philipp