LTS provides a wrapper for Jasmine and Mocha. The code for LTS is open source, so it can be easily tailored to work with other frameworks as well.
The testing service comprises a global $T object that contains methods to create components, run callbacks, fire application events, and destroy components. The code for the $T API can be found at https://github.com/forcedotcom/LightningTestingService/blob/master/Lightning-component-tests/test/default/staticresources/lts_testutil.resource.
Salesforce recommends that you write and test for the following behaviors in Lightning Components:
| Test use case | Description |
| DOM rendering |
Validates that components are added where and when they should be. |
| Component state |
Ensures that components respond as expected. |
| Server-side callback response |
Gets the right response from a call to another service or resource. |
