eth-gas-reporter is a Mocha reporter for Ethereum test suites which provides you insights into your Smart Contract's gas usage. Using it you can see a breakdown of gas usage per unit test, metrics for method calls and deployments as well as costs of deploying and using your Smart Contract system.
Protip: If you're using Truffle or Hardhat you can find more information about official support and proper setup in the README.
- cgewecke