iox-#2370 Fix Bzlmod dev_dependency setup

[lalten]

Notes for Reviewer

Fix Bzlmod dev_dependency setup

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References

• Closes incorrect Bazel dev_dependency setup #2370

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 78.70%. Comparing base (aa13b0a) to head (776e5b6).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2371   +/-   ##
=======================================
  Coverage   78.69%   78.70%           
=======================================
  Files         440      440           
  Lines       16981    16981           
  Branches     2361     2361           
=======================================
+ Hits        13364    13365    +1     
  Misses       2736     2736           
+ Partials      881      880    -1     

Flag	Coverage Δ
unittests	78.50% <ø> (+<0.01%)	⬆️
unittests_timing	15.36% <ø> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

see 1 file with indirect coverage changes

[elfenpiff]

@lalten looks fine. The MinGW CI failure is a flaky test, which we can ignore, but the Ubuntu bazel target fails.

I assigned @elBoberido since he may has some more insights here.

[elBoberido]

@lalten the bzlmod code came from a community member and I'm not that familiar with the code. Can you specify which public targets are affected by the dev dependencies?

[lalten]

@lalten the bzlmod code came from a community member and I'm not that familiar with the code. Can you specify which public targets are affected by the dev dependencies?

Buildifier is unconditionally depended on in the root BUILD

iceoryx/BUILD.bazel

Line 18 in d628cb7

load("@buildifier_prebuilt//:rules.bzl", "buildifier")

iceoryx/BUILD.bazel

Lines 61 to 65 in d628cb7

	# Execute `bazel run //:buildifier` to fix formating of all starlark files in the workspace
	buildifier(
	name = "buildifier",
	verbose = True,
	)

Googletest is depended on in a regular cc_library with public visibility:

iceoryx/iceoryx_hoofs/BUILD.bazel

Line 107 in d628cb7

"@googletest//:gtest",

[elBoberido]

Okay, the buildifier is definitely a dev dependency. The iceoryx_hoofs_testing is actually also a dev dependency but I'm not sure how this could be modeled with bazel. It is basically meant to be used for tests which use iceoryx. For example it contains a logger which suppresses all the output but if a test fails, it prints all log messages to help debugging.

Is there another way to mark this library as a dev dependency but still make it available to users?

In the end, I guess it should not matter and as long as one does depend only on e.g. iceoryx_hoofs bazel will not require gTest to be available. Please correct me if I'm wrong.

[lalten]

dev dependencies can not be depended on outside the root module, i.e. as soon as iceoryx is used as Bzlmod dependency of another project (which of course is the intended use case), dev dependencies are not there anymore.

See https://bazel.build/rules/lib/globals/module#parameters_1

dev_dependency: If true, this dependency will be ignored if the current module is not the root module or --ignore_dev_dependency is enabled.

[lalten]

Note that Bazel will want to analyze the entire graph, so even if a user doesn't want to depend on iceoryx_hoofs_testing (or buildifier), these Bazel repos must be visible to the root module.

Looks like the buildifier usage is actually ok, here is another repo with the same setup:
https://github.com/aspect-build/rules_ts/blob/v3.3.1/MODULE.bazel#L26
https://github.com/aspect-build/rules_ts/blob/v3.3.1/BUILD.bazel#L3

[lalten]

🤷

❯ cat MODULE.bazel
module(name = "test")

bazel_dep(name = "org_eclipse_iceoryx")
git_override(
    module_name = "org_eclipse_iceoryx",
    commit = "d628cb7111051ae1cd27620d9a621a366d5cac82",
    remote = "https://github.com/eclipse-iceoryx/iceoryx",
)
❯ bazel build @org_eclipse_iceoryx//:iceoryx_binding_c
WARNING: Target pattern parsing failed.
ERROR: Skipping '@org_eclipse_iceoryx//:iceoryx_binding_c': error loading package '@@org_eclipse_iceoryx~//': Unable to find package for @@[unknown repo 'buildifier_prebuilt' requested from @@org_eclipse_iceoryx~]//:rules.bzl: The repository '@@[unknown repo 'buildifier_prebuilt' requested from @@org_eclipse_iceoryx~]' could not be resolved: No repository visible as '@buildifier_prebuilt' from repository '@@org_eclipse_iceoryx~'.
ERROR: error loading package '@@org_eclipse_iceoryx~//': Unable to find package for @@[unknown repo 'buildifier_prebuilt' requested from @@org_eclipse_iceoryx~]//:rules.bzl: The repository '@@[unknown repo 'buildifier_prebuilt' requested from @@org_eclipse_iceoryx~]' could not be resolved: No repository visible as '@buildifier_prebuilt' from repository '@@org_eclipse_iceoryx~'.
INFO: Elapsed time: 1.897s
INFO: 0 processes.
ERROR: Build did NOT complete successfully

[elBoberido]

Okay, this is weird. Why should the buildifier be needed in order to build iceoryx_hoofs? Bazel has some weird dependency handling.

Do you have time to check it there is an obvious flaw in the bzlmod setup?