testdouble.js vs Lens comparison of testing frameworks
What are the differences between testdouble.js and Lens?

	testdouble.js https://github.com/testdouble/testdouble.js	Lens https://github.com/spencer-mortensen/lens
Programming language	JavaScript	PHP
Category	Unit Testing, Intergration Testing	Unit Testing
General info	This library was designed to work for both Node.js and browser interpreters and it encourages the TDD (Test Driven Development) Test doubles can be used with conjuction of other test frameworks such as Jasmine, Jest, Chai, QUnit, Mocha, Tape etc.	Lens is a unit-testing framework for PHP Lens is a unit-testing framework for PHP that needs no assertions
xUnit Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.	Yes It is compatible with xUnit and supportsxUnit XML output	N/A
Client-side Allows testing code execution on the client, such as a web browser	No	Yes It can test front end components
Server-side Allows testing the bahovior of a server-side code	Yes Testdouble is primarily used to test server-side functions, behaviours and components	Yes It can test back-end behaviour
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	MIT License	N/A
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)	Yes Testdouble includes inbuilt support for mocking	N/A
Grouping Allows organizing tests in groups	N/A	N/A
Other Other useful information about the testing framework