Test’em vs Cucumber-JVM comparison of testing frameworks
What are the differences between Test’em and Cucumber-JVM?

Test’em

https://github.com/testem/testem

Cucumber-JVM

https://github.com/cucumber/cucumber-jvm
Programming language

JavaScript

Java

Category

Unit Testing

Acceptance Testing

General info

A Unit testing test runner for JavaScript

Test'em is framework agnostic and has support for Jasmine, Qunit, Mocha and others through custom test framework adapters. It canalso run tests on all major browsers as well as Node and Phantomjs

Cucumber-JVM is a pure Java implementation of Cucumber

The specifications are written in plain texts, which allows them to be easily understandable by all stakeholders.
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

It has an xUnit reporter

No

Client-side
Allows testing code execution on the client, such as a web browser

Yes

You can test the front-end part like the GUI using cucumber with serenity, they integrate well to test your front-end.
Server-side
Allows testing the bahovior of a server-side code

Yes

You can test back-end components such as API's using rest&soap clients, and databases
Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

Yes

Using the cucumber extension aruba you can create fixures in two steps: 1.Create a fixtures-directory; 2.Create fixture files in this directory
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.

Yes

You can group your fixtures inside your fixtures directories
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

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

By using all of RSpec’s supported mocking frameworks (RSpec, Mocha, RR, Flexmock)
Grouping
Allows organizing tests in groups

No

Other
Other useful information about the testing framework