Introduce unit tests

[achumachenko-cloudinary]

Implemented modifications to allow unit testing and end-to-end testing of the script functionality.

[mgriff]

I've added few suggestions/questions in line.

A more general comment on the folder structure, I personally think that it looks cleaner to have all the tests under one folder (rather that with the source files). I realise it can come down to personal choice but there are a few reasons I think we should separate them out:

• It separates out the core code from the tests files which makes it easier IMO for people to understand the roles of the individual files
• It helps if you need to run a subset of tests, for example if the different test types are in subfolders of a root test folder, you can use jest test/*/* for all tests, and jest test/unit/* or jest test/integration/* for unit or full e2e tests.
• This is the same approach that the Cloudinary JS SDK follows so would be more consistent across our code bases

[achumachenko-cloudinary]

RE:

A more general comment on the folder structure, I personally think that it looks cleaner to have all the tests under one folder (rather that with the source files). I realise it can come down to personal choice but there are a few reasons I think we should separate them out:

• It separates out the core code from the tests files which makes it easier IMO for people to understand the roles of the individual files
• It helps if you need to run a subset of tests, for example if the different test types are in subfolders of a root test folder, you can use jest test/*/* for all tests, and jest test/unit/* or jest test/integration/* for unit or full e2e tests.
• This is the same approach that the Cloudinary JS SDK follows so would be more consistent across our code bases

I don't think it makes sense to mimic the setup of the SDK (we already use different testing framework jest vs mocha in SDK).

My reasoning has been:

• This is a small app so it should be easy to make sense of where tests are
• You can still run specific tests jest lib/input/*

This doesn't seem to be essential aspect of the implementation so I prefer moving faster vs getting things exactly right.
LMK what you think @mgriff

Appreciate all your time and the feedback! 🤘

Cheers!

[mgriff]

LGTM