Add law tests to the parser

[zainab-ali]

The lsug markup uses an applicative parser. It has cats type class instances for functor and alternative. While the parser is unit tested, the instances themselves could use law tests.

Potential Solution

As we use munit for unit testing, we can add laws with discipline-munit. This is described in the cats laws documentation. The tests should be added in the lsug.markup.ParserSpec. Provided there are no test failures, the parser shouldn't be changed.

Prerequisites

You should be familiar with the some type classes, such as Functor. You should also understand the concept of unit testing.

What you'll learn

• the alternative type class
• how to use munit
• the basics of property testing
• what is meant by a type class law, and how to test it with the discipline library.

  Getting started

  Read our Contributor Guide to get set up.

[kxa14]

I'm working on this.

[zainab-ali]

Thanks for working on this @kxa14 !