Testing Bash scripts

When you need to test a bash script you can use bats for that. That's how it is done:

#!/usr/bin/env bats

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

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

Full article with different tools overview: https://medium.com/wemake-services/testing-bash-applications-85512e7fe2de