TestNG vs Espec comparison of testing frameworks
What are the differences between TestNG and Espec?

TestNG

https://testng.org/doc/documentation-main.html

Espec

https://github.com/antonmi/espec
Programming language

Java

Elixir

Category

Unit Testing, Intergration Testing, End-to-End Testing

Unit Testing

General info

TestNG is a testing framework for the Java programming language inspired by JUnit and NUnit

TestNG is similar to JUnit and NUnit but with newer functionalities such as: annotations, test that your code is multithread safe, flexible test configuration, support for data-driven testing (with @DataProvider), support for parameters, powerful execution model (no more TestSuite) and more... It's also designed to cover all categories of tests unit, functional, end-to-end, intergration... etc

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)
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

No

No

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

Yes

The scope of testing with testNg is wide and you can test various front-end functionalities and behaviours with it

Yes

Front-end components can be tested; there is also espec_phoenix for the Phoenix web framework
Server-side
Allows testing the bahovior of a server-side code

Yes

You can test server-side functionalities and behaviours with TestNg

Yes

databases and server behaviour can be tested using Espec
Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

Yes

Fixtures are inbuilt into testNG, these are the annotations which are: @BeforeSuite, @AfterSuite, @BeforeTest, @AfterTest, @BeforeGroups, @AfterGroups, @BeforeClass, @AfterClass, @BeforeMethod, @AfterMethod

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.

Yes

You can use various fixtures to setup environments for group tests

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

N/A

Licence
Licence type governing the use and redistribution of the software

Apache License 2.0

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 Use of an external library like mockit which intergrates well with testNG

Yes

It has a Built-in mocking functionality on top of Erlang 'meck' library
Grouping
Allows organizing tests in groups

Yes

Multiple test cases can be grouped more easily by converting them into testng.xml file, in which you can make priorities which test case should be executed first

Yes

By use of context blocksand tags functions
Other
Other useful information about the testing framework