objc_import missing data argument

[xiemotongye]

Description of the feature request:

Hi wonderful Bazel folks,

This is a feature request.

I'd noticed that objc_import--unlike most other cc rules(cc_import, cc_library, objc_library)--doesn't allow you to specify data.
I think objc_import should be equivalent to objc_library. It's so weird that objc_import does not support the data argument.

What underlying problem are you trying to solve with this feature?

I'm using a .a file with some resources. When I specify data to objc_import, bazel told me: no such attribute 'data' in 'objc_import' rule.

Which operating system are you running Bazel on?

macOS 12.6

What is the output of bazel info release?

release 6.0.0rc4

If bazel info release returns development version or (@non-git), tell us how you built Bazel.

No response

What's the output of git remote get-url origin; git rev-parse master; git rev-parse HEAD ?

git@github.com:bazelbuild/bazel.git
89eba259031ff29136fdb59351adc1e754004672
7ccc66108f08f7b6c6f6e5229f70f29962ea19ce

Have you found anything relevant by searching the web?

Yes.
Just found objc_import missing deps argument.
This issue only mentioned deps arguments, but no mention for data arguments.

Any other information, logs, or outputs that you want to share?

No response

[cpsauer]

+1 on the utility of this

[As food for thought: Might it just make sense to mostly unify these rules?]

[cpsauer]

(objc_import is starlarkified, right? Perhaps that makes this a good time... I started to look into, but wasn't sure how the data attrs were getting gathered up into providers in the cc_import equivalent--perhaps they're traversed with an aspect?--nor what the SKIP_CONSTRAINTS_OVERRIDE was about. If anyone knows--or knows who would know--please say.)

[keith]

As far as how data is used in apple targets that is from an aspect in rules_apple, so I would try adding the same attr as objc_library (this one

bazel/src/main/starlark/builtins_bzl/common/objc/objc_library.bzl

Line 124 in 0acc817

"data": attr.label_list(allow_files = True),

) and seeing if that "just works" the only place I can see objc_library using that directly is for this

bazel/src/main/starlark/builtins_bzl/common/objc/objc_library.bzl

Line 94 in 0acc817

dependency_attributes = ["deps", "data", "binary", "xctest_app"],

which objc_import doesn't have

[cpsauer]

Thanks Keith!

Gave that a quick whirl, but the data don't get picked up and bundled as they would with objc_library. Any ideas?

(Figured I had comparative advantage if it were easy, given a real world test case, and already knowing how to use --experimental_builtins_bzl_path="%workspace%", but I think you (and others) definitely have advantage wrt understanding the gather-up process.)

[keith]

Ah yea need to add it here too https://github.com/bazelbuild/rules_apple/blob/d5d6d58af8b96365e9b9a9d093d4fb4b2f4dd912/apple/internal/aspects/resource_aspect.bzl#L134-L135

[cpsauer]

Got it. Looks like resources.collect no-ops gracefully if the attrdoesn't exist--so that change is our first move.

Should I be concerned also about, e.g., cc_binaries failing to collect the data? (I was surprised to see these not getting passed up e.g. via some cc provider.)

[cpsauer]

It does still does seem like objc_import is so very close to being able to just be implemented as a facade around objc_library. objc_library would just need to be able to take .a files, like cc_library.

[cpsauer]

Prerequisite change merged into rules_apple today.

Added the core change in #20716 (have ofc verified that they work together.)