# test > Evaluate condition. > If it is true, returns 0 exit status, otherwise returns 1. - Test if given variable is equal to given string: `test $MY_VAR == '/bin/zsh'` - Test if given variable is empty: `test -z $GIT_BRANCH` - Test if file exists: `test -e {{filename}}` - Test if directory not exists: `test ! -d {{path/to/directory}}` - If-else statement: `test {{condition}} && echo "true" || echo "false"`