Lens vs Buster.JS comparison of testing frameworks
What are the differences between Lens and Buster.JS?

Lens

https://github.com/spencer-mortensen/lens

Buster.JS

https://busterjs.readthedocs.io
Programming language

PHP

JavaScript

Category

Unit Testing

Unit Testing, Browser Automation

General info

Lens is a unit-testing framework for PHP

Lens is a unit-testing framework for PHP that needs no assertions

Buster.JS is a JavaScript test framework for node and browsers.

Buster.JS is a new JavaScript testing framework. It does browser testing by automating test runs in actual browsers (think JsTestDriver), as well as Node.js testing. It has a bunch of great features.
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

N/A

Yes

Buster.Js is a xUnit style Test Framework
Client-side
Allows testing code execution on the client, such as a web browser

Yes

It can test front end components

Yes

It does browser testing with browser automation, QUnit style static HTML page testing, testing in headless browsers and more front-end components and functionality
Server-side
Allows testing the bahovior of a server-side code

Yes

It can test back-end behaviour

Yes

It is a Node.js testing toolkit as well which means it can test back-end behaviour and functionality as well as run in a server environment
Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

N/A

N/A

Group fixtures
Allows defining a fixed, specific states of data for a group of tests (group-fixtures). This ensures specific environment for a given group of tests.

N/A

N/A

Generators
Supports data generators for tests. Data generators generate input data for test. The test is then run for each input data produced in this way.

N/A

Licence
Licence type governing the use and redistribution of the software

N/A

BSD License

Mocks
Mocks are objects that simulate the behavior of real objects. Using mocks allows testing some part of the code in isolation (with other parts mocked when needed)

N/A

Buster.JS ships with Sinon.JS. every test in a test case has a sandbox associated with it, making it easy to mock and stub
Grouping
Allows organizing tests in groups

N/A

Other
Other useful information about the testing framework