[13/20] gitlab: Use bash to avoid needing a_test_which_does_not_exist

Bash allows for variables to expand only if non-empty:

	$ var=test
	$ echo ${var:+"$var"}
	test
	$ echo ${var:+"-k $var"}
	-k test
	$ var=
	$ echo ${var:+"-k $var"}

Use this feature to avoid the workaround.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 .gitlab-ci.yml | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

On Fri, Mar 06, 2020 at 08:07:27PM -0700, Simon Glass wrote:
> Bash allows for variables to expand only if non-empty:
> 
> 	$ var=test
> 	$ echo ${var:+"$var"}
> 	test
> 	$ echo ${var:+"-k $var"}
> 	-k test
> 	$ var=
> 	$ echo ${var:+"-k $var"}
> 
> Use this feature to avoid the workaround.
> 
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
> 
>  .gitlab-ci.yml | 6 +-----
>  1 file changed, 1 insertion(+), 5 deletions(-)
> 
> diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
> index bbd05aa872..05f56c6d19 100644
> --- a/.gitlab-ci.yml
> +++ b/.gitlab-ci.yml
> @@ -36,17 +36,13 @@ stages:
>        if [[ $ret -ne 0 && $ret -ne 129 ]]; then
>          exit $ret;
>        fi
> -    # "not a_test_which_does_not_exist" is a dummy -k parameter which will
> -    # never prevent any test from running. That way, we can always pass
> -    # "-k something" even when $TEST_PY_TEST_SPEC doesnt need a custom
> -    # value.
>      - virtualenv -p /usr/bin/python3 /tmp/venv
>      - . /tmp/venv/bin/activate
>      - pip install -r test/py/requirements.txt
>      - export PATH=/opt/qemu/bin:/tmp/uboot-test-hooks/bin:${PATH};
>        export PYTHONPATH=/tmp/uboot-test-hooks/py/travis-ci;
>        ./test/py/test.py --bd ${TEST_PY_BD} ${TEST_PY_ID}
> -        -k "${TEST_PY_TEST_SPEC:-not a_test_which_does_not_exist}"
> +        ${TEST_PY_TEST_SPEC:+"-k ${TEST_PY_TEST_SPEC}"}
>          --build-dir "$UBOOT_TRAVIS_BUILD_DIR";
>        ret=$?;
>        if [[ $ret -ne 0 ]]; then

Please change the comment to note that other less-than-obvious bash
feature being used here, thanks!