"Waffle" is the most advanced Smart Contract testing framework. It integrates nicely with development frameworks such as Ganache or Hardhat, is minimalistic with only a few dependencies, has a nice and easy to remember syntax and is fast in both, development- and execution time.
Protip: You should definitely spend some time to read through their documentation. The Chai matchers docs in particular explain how you can make use of their custom matchers to e.g. check for BigNumbers or events emitted by your contracts.
- TrueFi Engineering