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

	Espec https://github.com/antonmi/espec	testdouble.js https://github.com/testdouble/testdouble.js
Programming language	Elixir	JavaScript
Category	Unit Testing	Unit Testing, Intergration Testing
General info	BDD driven testing framework for Elixir It is a testing framework written from scratch which is inspired by RSpec and the main idea is to close to its perfect DSL (Domain Specific Language)	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.
xUnit Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.	No	Yes It is compatible with xUnit and supportsxUnit XML output
Client-side Allows testing code execution on the client, such as a web browser	Yes Front-end components can be tested; there is also espec_phoenix for the Phoenix web framework	No
Server-side Allows testing the bahovior of a server-side code	Yes databases and server behaviour can be tested using Espec	Yes Testdouble is primarily used to test server-side functions, behaviours and components
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	MIT 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)	Yes It has a Built-in mocking functionality on top of Erlang 'meck' library	Yes Testdouble includes inbuilt support for mocking
Grouping Allows organizing tests in groups	Yes By use of context blocksand tags functions	N/A
Other Other useful information about the testing framework