Support git submodule filters

[rarkins]

Discussed in #33027

^{Originally posted by Kobzol December 10, 2024}

Tell us more.

Hi! I'm a member of the Rust infra team, and I'd like to get renovatebot working on the https://github.com/rust-lang/rust repository, which hosts the Rust toolchain (compiler, standard library etc.), using the Forking Renovatebot GitHub app.

Currently, I'm facing two blockers:

• We need to use nightly cargo (this is already tracked in Use cargo nightly #15728 and other issues)
• Slow speed of git submodules checkout

For updating certain Rust lockfiles, we need to checkout submodules in the Rust repository. However, the repo has a lot of submodules, some of which are very large (e.g. LLVM or GCC). I tried to set "cloneSubmodules": true, but then the renovatebot job times out after thirty minutes.

I wonder if it would be possible to either:

• Allow selecting which submodules will be checked out. We actually need only a few small-ish submodules for the lockfile updates, but currently Renovatebot either checks out all submodules or none.
• Make submodule checkouts faster, by using some git magic. For example, in the Rust repo, we have a custom script that makes the checkouts faster by downloading archives from GitHub (although this is not a general solution, of course).

Thanks!

[rarkins]

FYI @Kobzol

[rarkins]

Closed by #33115

Waiting for the next update of the Mend app and it will be available

[Kobzol]

Thank you for implementing this! Is there a way to find out what version is currently deployed in the Mend Renovate GitHub app? I haven't found it anywhere, and it doesn't seem to be deployed yet:

[rarkins]

See https://docs.renovatebot.com/mend-hosted/hosted-apps-config/#renovate-version

[Kobzol]

Thanks! I tried to search for it in the log, but it was a bit later than I expected.

[Kobzol]

I can confirm that this works and it has helped unblock Renovatebot submodule support in rust-lang/rust 🎉 Thank you very much! Now only the nightly Cargo issue remains.