ERT: Emacs Lisp Regression Testing

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ERT is a tool for automated testing in Emacs Lisp. Its main features are facilities for defining tests, running them and reporting the results, and for debugging test failures interactively.

ERT is similar to tools for other environments such as JUnit, but has unique features that take advantage of the dynamic and interactive nature of Emacs. Despite its name, it works well both for test-driven development (see and for traditional software development methods.

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