bats-core/bats-assert bats-assert is a helper library providing common assertions for Bats. In the context of this project, an assertion is a function that perform a test and returns 1 on failure or 0 on success. To make debugging easier, the assertion also outputs relevant information on failure. The output is formatted for readability. To make assertions usable outside of @test blocks, the output is sent to stderr. The most recent invocation of Bats' run function is used for testing assertions on output and status code.