Set up the Testing Environment, you must have truffle installed.

npm install truffle -g truffle

Some dependancies

 npm install --save-dev chai
 npm install --save-dev chai-bignumber

Then in the working folder, suggest a new folder for this

truffle init

You may need to edit the Migrations.sol file to rename the constructor as follows:

From this

  function Migrations() public {
    owner = msg.sender;
  }

To This

  constructor() public {
    owner = msg.sender;
  }

Then you can execute To compile the code

truffle compile

To migrate or upload the contract to your engine, as configured in the truffle-config.js

truffle migrate

To run a test use

truffle test
or
watch -c truffle test test/AENToken.test.js

An approach I use is to install nodemon or watch to re-run the tests when you save the file.