lambspec

Assertion library for Java >= 8

Downloading

Accessible from Maven central. Coordinates: com.pholser:lambspec-{module}:{version}. You will need at minimum lambspec-core.

Examples

The best place to begin exploring is in test class ExpectationsTest.

Javadoc is here.

Features

• RSpec-like syntax for nominating test subjects and specifying expectations on them:

  expect("foo").to(s -> s.startsWith("f"));

• Uses predicates as the means for specifying expectations on test subjects. Predicate is a functional interface, so you can use lambda expressions and method references to specify the expectations more succinctly and sweetly.

• Optional: Adapters for Hamcrest matchers and Guava predicates.

• Optional: Similar syntax for establishing assumptions for JUnit theories.

Caveats

When an expectation or assumption is not met, the raised exception's message will contain the toString() of the expectation. A lambda expression's toString() is not terribly pretty or helpful. If evocative assertion error messages are important to you, you may want to create implementations of Predicate, anonymous or otherwise, and override toString() to your liking.

About

lambspec was written by Paul Holser, and is distributed under the MIT License.

The MIT License

Copyright (c) 2014-2016 Paul R. Holser, Jr.

Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
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permit persons to whom the Software is furnished to do so, subject to
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The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

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