Re: [PATCH v2 2/2] test-lib: introduce required prereq for test runs

From: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date: Nov 19, 2021, 11:13 UTC
Message-ID: <211119.865yso4a9y.gmgdl@evledraar.gmail.com>
In-Reply-To: <20211117090410.8013-3-fs@gigacodes.de>

On Wed, Nov 17 2021, Fabian Stelzer wrote:

> In certain environments or for specific test scenarios we might expect a
> specific prerequisite check to succeed. Therefore we would like to
> trigger an error when running our tests if this is not the case.

trigger an error but...

> To remedy this we add the environment variable GIT_TEST_REQUIRE_PREREQ
> which can be set to a comma separated list of prereqs. If one of these
> prereq tests fail then the whole test run will abort.

..here it's "abort the whole test run". If that's what you want use BAIL_OUT, not error. See: 234383cd401 (test-lib.sh: use "Bail out!" syntax on bad SANITIZE=leak use, 2021-10-14)

Show 8 quoted lines

> +GIT_TEST_REQUIRE_PREREQ=<list> allows specifying a comma speparated list of
> +prereqs that are required to succeed. If a prereq in this list is triggered by
> +a test and then fails then the whole test run will abort. This can help to make
> +sure the expected tests are executed and not silently skipped when their
> +dependency breaks or is simply not present in a new environment.
> +
>  Naming Tests
>  ------------

For other things we specify via lists such as GIT_SKIP_TESTS that's space-separated, but here it's comma-separated, isn't that just a leaky abstraction in this case? I.e. this is exposing a previously internal-only implementation detail of the prereq code.

It's less painful in shellscript if anything like this supports space-separated parameters, as you can interpolate them more easily in any wrapper script without using "tr" or the like...