2.3 Test Selectors

Functions like ert accept a test selector, a Lisp expression specifying a set of tests. Test selector syntax is similar to Common Lisp’s type specifier syntax:

Selectors that are frequently useful when selecting tests to run include t to run all tests that are currently defined in Emacs, "^foo-" to run all tests in package foo (this assumes that package foo uses the prefix foo- for its test names), result-based selectors such as (or :new :unexpected) to run all tests that have either not run yet or that had an unexpected result in the last run, and tag-based selectors such as (not (tag :causes-redisplay)) to run all tests that are not tagged :causes-redisplay.