Add toolchain param to affected actions

[kotlaja]

This is part of migrations of Automatic Exec Groups (AEGs) where a toolchain parameter should be set inside actions which use executable or tools from a toolchain.

AEGs are under an incompatible flag right now, but will be flipped soon in Bazel 7. I've added this change since I was manually fixing rules_nodejs, which depends on bazel-lib. I can't fully test this change since I need at least Bazel 7, but Bazel@Head raises non related errors to my change. That's why there might be more related updates once bazel-lib supports Bazel 7.

Still, as I already mentioned, adding a toolchain parameter is masked by the incompatible flag, so these changes don't do anything right now. But it can help you with your migration in the near future when AEGs are enabled by default and you are forced to update actions which use toolchains.

Also note that the toolchain parameter is available from Bazel 6, but the full logic (and the incompatible flag) will be available from Bazel 7.

Please check official documentation for Automatic Exec Groups for additional info.

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Type of change

• New feature or functionality (change which adds functionality)

Test plan

• Manual testing; please provide instructions so we can reproduce:
• Use (at least) Bazel 7 and add --incompatible_auto_exec_groups flag.

[CLAassistant]

All committers have signed the CLA.

[kotlaja]

Hi @alexeagle, Nevena here from Bazel team in Munich! :) Can you please take a look at this PR?

[kormide]

Looks like this needs a bazel run //docs:update for docs tests.

[kormide]

@alexeagle Do you think we want this backported to the 1.x branch as well?

[alexeagle]

We can say that bazel-lib 1.x doesn't support Bazel 7.0 so I don't think we need to backport this. If someone complains I can revisit.

[alexeagle]

@kotlaja I tried to update the docs for you, but you didn't check the "allow maintainers to add commits" box

% git commit -a -m "bazel run docs:update"
[kotlaja/main f452708] bazel run docs:update
 1 file changed, 2 insertions(+), 1 deletion(-)
alexeagle@MacBook-Pro-8 bazel-lib % git push
Enumerating objects: 7, done.
Counting objects: 100% (7/7), done.
Delta compression using up to 8 threads
Compressing objects: 100% (4/4), done.
Writing objects: 100% (4/4), 493 bytes | 44.00 KiB/s, done.
Total 4 (delta 3), reused 0 (delta 0), pack-reused 0
remote: Resolving deltas: 100% (3/3), completed with 3 local objects.
To github.com:kotlaja/bazel-lib.git
 ! [remote rejected] kotlaja/main -> kotlaja/main (permission denied)
error: failed to push some refs to 'github.com:kotlaja/bazel-lib.git'

[kotlaja]

Sorry, I was on a vacation. Thanks for the help here!

Hm, allow maintainers to add commits was already checked, not sure why it didn't work.
I've run the command now, please take another look.

[thesayyn]

@kotlaja i meant to speak with somebody from bazel team about this. does adding this parameter make the action incompatible with older versions of bazel where this attribute isn't recognized or does it get simply ignored?