When a TTY is attached to the test unit, grep -q will generate SIGPIPE
for the previous command in the pipeline which in combo with `pipefail`
will cause the command to fail with exit status 141 which will fail the
test.
Replace with >/dev/null to avoid this from happening.
See also https://www.gnu.org/software/grep/manual/html_node/Usage.html
> There is a related problem with Bash’s set -e -o pipefail. Since grep
> does not always read all its input, a command outputting to a pipe read
> by grep can fail when grep exits before reading all its input, and the
> command’s failure can cause Bash to exit.
Co-authored-by: Yu Watanabe <watanabe.yu+github@gmail.com>
This also makes shebang always use env command, and drops unnecessary
'bash -c' or 'sh -c' when a signle command is invoked in the shell,
like sleep or echo.
Daan De MeyerandYu Watanabe