A pattern has emerged where a integration tests check for the
availability of an external tool (`git`, `taplo`, `gpg`, ...) and skip
the test (by simply passing it) when it is not available. To check this,
the program is run with the `--version` flag.
Some tests require that the program be available at least when running
in CI, by calling `ensure_running_outside_ci` conditionally on the
outcome. The decision is up to each test, though, the utility merely
returns a `bool`.
If a signing key is not configured, the user's email will be
used as the signing key. This aligns with `git`'s behavior
and allows the users to not specify the key in their configs
given that they have a key associated with their email.
Follows up 7552f939c6c2 "tests: disable most gpg integration tests on Windows."
I couldn't find this test failing in a few samples before, but it does now.
This adds a guard to the gpg signing tests which will skip the test if
`gpg` is not installed on the system.
This is done in order to avoid requiring all collaborators to have setup
all the tools on their local machines that are required to test commit
signing.
