pseudo actions omitted from Target.actions

[shahms]

Description of the problem / feature request:

When accessing Target.actions from an aspect, pseudo actions are absent.

Feature requests: what underlying problem are you trying to solve with this feature?

Replacing extra_actions with aspects.

Bugs: what's the simplest, easiest way to reproduce this bug? Please provide a minimal example if possible.

Given BUILD:

# BUILD
action_listener(
    name = "py_listener",
    extra_actions = [":debug"],
    mnemonics = ["Python"],
)

extra_action(
    name = "debug",
    cmd = "echo 'Action Executed' > $(output $(ACTION_ID).txt)",
    out_templates = [
        "$(ACTION_ID).pb",
    ],
)

py_library(
    name = "library",
    srcs = ["library.py"],
)

And aspect.bzl

def _impl(target, ctx):
    print([a.mnemonic for a in target.actions])
    return []

debug = aspect(
    implementation = _impl,
)

Running the commands yields:

$ bazel build --experimental_action_listener=//dummy:py_listener //dummy:library
...
$ cat $ cat bazel-out/k8-fastbuild/extra_actions/dummy/debug/dummy/5a77db9045fb63dcc930dd78ea2df50dabf4ae0aabadcd8176ede0cbff2b5c1e.txt
Action Executed
$ bazel build --aspectc=//dummy:aspect.bzl%debug //dummy:library
$ bazel build --aspects=dummy/aspect.bzl%debug //dummy:library
INFO: Build option --experimental_action_listener has changed, discarding analysis cache.
DEBUG: /usr/local/google/home/shahms/src/kythe/dummy/aspect.bzl:2:10: []
...
$

(Note, in particular, the empty list of action mnemonics in the DEBUG line)

What operating system are you running Bazel on?

Ubuntu

What's the output of bazel info release?

release 4.0.0

[shahms]

It looks like this is somewhat intentional:

  void addPyExtraActionPseudoAction() {
    if (ruleContext.getConfiguration().getActionListeners().isEmpty()) {
      return;
    }

Just removing that check fixes the issue, although I'm not sure about other impact it may have.

[comius]

I believe pseudo actions were added just to support extra_actions and will be removed.

Is there something you can't access using an aspect? The info should be there.

[shahms]

When migrating from extra_actions to aspects, it's simplest to avoid changing too much at once and there remain rule implementations which only expose relevant information via pseudo actions (which were, indeed, only added to support extra_action). I don't think it's particularly critical that they remain, but it's a stumbling block when migrating.

[comius]

Ah ok, if it helps you move faster, please submit a PR (maybe you need to update Starlarkified calls as well). But consider pseudo actions deprecated.

[shahms]

At this point I believe we've already worked around the problem, but it was a speedbump to do so.

[github-actions]

Thank you for contributing to the Bazel repository! This issue has been marked as stale since it has not had any activity in the last 1+ years. It will be closed in the next 90 days unless any other activity occurs. If you think this issue is still relevant and should stay open, please post any comment here and the issue will no longer be marked as stale.