Run unit tests for bash shell scripts

Usage: bashtest.sh [-t pattern] [file ...]
Run unit tests for bash shell scripts, unit tests are functions with TEST_ prefix
-h: help
-t: only run tests that match regex pattern
file: test files containing unit test functions, default is all *.test.sh files

Examples:
bashtest.sh
bashtest.sh helloworld.test.sh

bashtest is a simple test runner for unit testing bash scripts. Unit tests are bash functions that start with TEST_, e.g. TEST_hello_world.

bashtest loads these functions from files ending in .test.sh in the current directory by default. It runs all the TEST_* functions and reports their results.

It prints whether each test passed or failed or was skipped. A test passes if its exit status is 0, it fails otherwise.

A test is skipped if it does not match the test inclusion pattern provided with the -t option

A sample script helloworld.sh is provided along with a test file helloworld.test.sh

This is how I write unit tests for bash scripts

In the main script

1. Set a variable, say testing, to check if the script should run normally, e.g. testing=false or is being tested, i.e. testing=true
2. Set the default value of testing to false
3. Check the variable before the main part of the script runs. If testing is true, return from the script. This way when the script is sourced by the testing script, all necessary functions and variables will be defined but the main part of the script will not execute.

In the testfile, at the very top

1. Set testing to true
2. Source the main script

The main script helloworld.sh

#!/bin/bash

# helloworld.sh

function hello {
  [[ -n $1 ]] || return 1
  echo "Hello $1!"
}


# default value of testing is false so return does not occur and main script runs
# set testing=true before sourcing this script for testing to prevent main script from running
${testing:=false} && return

# main
hello "${1:-World}"

The testfile helloworld.test.sh

# helloworld.test.sh

# source script containing functions to test
# set testing=true to prevent main script in helloworld.sh from running

testing=true . helloworld.sh

function TEST_hello_one_word {
  local name=World
  [[ $(hello $name) == "Hello $name!" ]]
}

function TEST_hello_two_words {
  local name="Le Monde"
  [[ $(hello "$name") == "Hello $name!" ]]
}

function TEST_hello_no_words {
  hello
  (($? != 0))
}

Running helloworld.sh directly produces normal output

$ ./helloworld.sh

Hello World!

$ ./helloworld.sh "Sam Lowry"

Hello Sam Lowry!

Running bashtest runs the unit tests from helloworld.test.sh and does not run the main part of helloworld.sh

$ bashtest.sh

Run tests from 1 testfiles: helloworld.test.sh

Matched 3 out of 3 tests to run from testfile helloworld.test.sh:

Run TEST_hello_one_word
Pass TEST_hello_one_word

Run TEST_hello_two_words
Pass TEST_hello_two_words

Run TEST_hello_no_words
Pass TEST_hello_no_words

Passed 3 tests from file helloworld.test.sh
Skipped 0 out of 3 tests from file helloworld.test.sh

Results summary for all tests:
Passed all tests from file helloworld.test.sh

A regular expression may be given with the -t option to only run tests that match

$ bashtest.sh -t "one|two"

Run tests from 1 testfiles: helloworld.test.sh
Skip tests that do not match regex patterns: one|two

Matched 2 out of 3 tests to run from testfile helloworld.test.sh

Run TEST_hello_one_word
Pass TEST_hello_one_word

Run TEST_hello_two_words
Pass TEST_hello_two_words

Failed 0 out of 3 tests from file helloworld.test.sh
Passed 2 out of 3 tests from file helloworld.test.sh
Skipped 1 out of 3 tests from file helloworld.test.sh

Results summary for all tests:
Passed all tests from file helloworld.test.sh