lint-whitespace assumes a branch "master" exists as a fallback for merge-base #23246

If git merge-base HEAD master (line 30) fails (eg, due to no master branch in the repo), the linter fails too.

I'm not sure what the ideal behaviour here is. Even if personal repos have a master branch, it's not necessarily going to be up to date.

We could just gate this fallback on [ "$CIRRUS_REPO_FULL_NAME" = "bitcoin/bitcoin" ], but if there's a way to figure out the correct base, that would be better...

I don't think this can be solved. If the base is missing or outdated, it won't be possible to figure it out.

Also, a gate on bitcoin/bitcoin won't work because the config is used by bitcoin-core/gui and bitcoin-core/qml.