bats

Automated testing framework for bash scripts

TLDR

Run test file

$ bats [test.bats]

Run all tests in directory

$ bats [tests/]

Tap output

$ bats --tap [test.bats]

Pretty formatting

$ bats --pretty [test.bats]

Filter by test name

$ bats --filter ["pattern"] [test.bats]

bats (Bash Automated Testing System) is a TAP-compliant testing framework for Bash scripts. It provides a simple syntax for writing tests and executing them with readable output.The tool enables test-driven development and continuous integration for shell scripts.

PARAMETERS

-c, --count

Count tests without running

-f, --filter pattern

Filter tests by name pattern

-t, --tap

Output in TAP format

-p, --pretty

Pretty print output

-r, --recursive

Run tests recursively

-j, --jobs num

Number of parallel jobs (requires GNU parallel)

-F, --formatter name

Output formatter (pretty, tap, tap13, junit)

-T, --timing

Add timing information to tests

-x, --trace

Print test commands as they are executed (like set -x)

--filter-tags tags

Only run tests matching all comma-separated tags

--filter-status status

Run tests by status from last run (failed, missed)

-o, --output dir

Directory to write report files

--no-tempdir-cleanup

Preserve test output temporary directory

--print-output-on-failure

Automatically print $output on failed tests

-v, --version

Display version number

TEST SYNTAX

$ #!/usr/bin/env bats

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

@test "files exist" {
  [ -f "/etc/hosts" ]
}

ASSERTIONS

Uses standard bash test operators:- [ -f file ] - File exists- [ "$a" = "$b" ] - String equality- [ $n -eq 4 ] - Numeric equality

HELPER FUNCTIONS

run command

Run command and capture output/status

load file

Load helper library

skip [reason]

Skip current test

CAVEATS

Tests run in subshells (limited side effects). No built-in assertion library (use test-helper). Parallel execution may have ordering issues. Debugging can be tricky.

HISTORY

bats was created by Sam Stephenson in 2011 to provide a simple testing framework for bash scripts, inspired by similar tools in other languages. The project was later forked and maintained as bats-core by the community.