What is "hamcrest"

Hamcrest is a framework that assists writing software tests in the Java programming language. It supports creating customized assertion matchers ('Hamcrest' is an anagram of 'matchers'), allowing match rules to be defined declaratively . These matchers have uses in unit testing frameworks such as JUnit and jMock.

Hamcrest has been ported to Java, C++, C#, Objective-C, Python, ActionScript 3, PHP, JavaScript, Erlang, and R.