Bash Automated Testing System

Overview

Bats is a TAP-compliant testing framework for Bash. It provides a simple way to verify that the UNIX programs you write behave as expected.

A Bats test file is a Bash script with special syntax for defining test cases. Under the hood, each test case is just a function with a description.

#!/usr/bin/env bats

@test "addition using bc" {
  result="$(echo 2+2 | bc)"
  [ "$result" -eq 4 ]
}

(The above overview section was stolen verbatim from the main projects README).

Install

Installing Locally

The steps below are to install bats at a user level (ie. ~/bin ~/.local/lib). However, Bats can also be installed at a system level (ie. root install, /usr/local) or as a submodule of a pre-existing git repository for CI purposes.

Run the commands below to install bats as well as the bats-assert helper library.

mkdir $HOME/.local/lib/bats
git clone https://github.com/ztombol/bats-support $HOME/.local/lib/bats/batscore
git clone https://github.com/ztombol/bats-assert $HOME/.local/lib/bats/batsassert
git clone --depth 1 https://github.com/sstephenson/bats $HOME/bats
cd $HOME/bats && ./install.sh $HOME/ && cd .. && rm -rf bats

First Tests

The examples below are two very simple bats test cases. They test whether or not the script's own file name exists and if the file name is 'test.bats' (two tests it should always pass).

test.bats

#!/usr/bin/env bats

setup() {
	# Import core and assert modules.
	load $HOME/.local/lib/bats/batscore/load.bash
	load $HOME/.local/lib/bats/batsassert/load.bash
}

@test "I exist," {
	[ -e $BATS_TEST_FILENAME ]
}

@test 'Therefore I am!' {
	assert_equal "$(basename $BATS_TEST_FILENAME)" 'test.bats'
}

Running the First Tests

./test.bats
 ✓ I exist!
 ✓ Therefore I am!

2 tests, 0 failures

Continued Documentation

This project is documented pretty well in the following locations. The below docs are also responsible for a lot of the content presented above.

Pick up where this note leaves off by Reading the Docs on Bats.

Main / Original Project README

Bats Assert README

Current / Bats Support Project Readme