I've been working through this, but don't yet understand.

In general, the script seems to be looking one directory up from where it should in a variety of cases. In the above example, it should have been "u-boot/files".

oof, this is probably because of $CROS_WORKON_SUBDIR.  we dropped support for that in  issue 805569 .

Thanks, that's really useful, I can dig through your CLs to try and better understand.

In your estimation, is it still feasible for TOT cros_mark_as_stable to support older branches?

There are alternatives such as using a pinned version of the script that still has support for older branches.

i think so.  it's not like we can't ever sunset this code ... random strawman:
- start a new module (or maybe extend chromite.lib.repo_manifest)
- add a helper func to get the version of the checkout
  - pull out portage_util.Ebuild.GetVersion to a more general util func
- add a constant to that module to say what min checkout version we support
  - going by current EOL systems, we'd start it at R22
- add a helper to say "is checkout at least version X"
  - if version X is older than the constant from above, issue a warning so we know we can clean up some code
- figure out what version CROS_WORKON_SUBDIR was removed
- update cros_mark_as_stable/whatever to use that version info to see if it needs to handle CROS_WORKON_SUBDIR

i suspect we're going to want this general framework as we write more utils that'll have to support older branches ...

I'm trying to think through the cleanest / easiest way to make this maintainable.

I'm also debating not solving that problem yet and just running cros_mark_as_stable from the branch (or at least testing to see how well that works today), with a bug to follow up and do it right.

I'd be okay with that if I had strong confidence in the bug being fixed soon.

CROS_WORKON_SUBDIR was removed in 10363.0.0.


This is the more useful backtrace:

chromite.lib.parallel.BackgroundFailure: <type 'exceptions.AssertionError'>: Could not find repo project at /b/swarming/w/ir/cache/cbuild/workspace/src/third_party/u-boot/
Traceback (most recent call last):
  File "/b/swarming/w/ir/cache/cbuild/repository/chromite/lib/parallel.py", line 602, in TaskRunner
    task(*x, **task_kwargs)
  File "/b/swarming/w/ir/cache/cbuild/repository/chromite/lib/parallel.py", line 800, in <lambda>
    fn = lambda idx, task_args: out_queue.put((idx, task(*task_args)))
  File "/b/swarming/w/ir/cache/cbuild/repository/chromite/scripts/cros_mark_as_stable.py", line 489, in _WorkOnEbuild
    manifest)
  File "/b/swarming/w/ir/cache/cbuild/repository/chromite/lib/portage_util.py", line 932, in RevWorkOnEBuild
    info = self.GetSourceInfo(srcroot, manifest)
  File "/b/swarming/w/ir/cache/cbuild/repository/chromite/lib/portage_util.py", line 782, in GetSourceInfo
    real_project = manifest.FindCheckoutFromPath(subdir_path)['name']
  File "/b/swarming/w/ir/cache/cbuild/repository/chromite/lib/git.py", line 683, in FindCheckoutFromPath
    raise AssertionError('Could not find repo project at %s' % (path,))

I believe the needs to be in either GetSourceInfo, or _ReadCrosWorkonVars.

Those two seem harder to split out from portage_util, and I'm not yet sure what else would need to be updated.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/chromite/+/3dbb2932da86d1e175e39e1f9a57d73609e2d16e

commit 3dbb2932da86d1e175e39e1f9a57d73609e2d16e
Author: Don Garrett <dgarrett@google.com>
Date: Fri Oct 05 22:43:19 2018

portage_util: Readd CROS_WORKON_SUBDIR compatibility.

CROS_WORKON_SUBDIR support was removed in
 https://crbug.com/805569 . This CL readds that support behind a
conditional flag.

That flag should be set only when processing branches older than
10363.0.0. This logic should be removed after all branches older than
that are EOL'd (including firmware / factory).

DO NOT SUBMIT, CONCEPT REVIEW ONLY.

This version works against the daisy_skate branch, but still needs
cleanup.

BUG= chromium:890017 
TEST=run_tests

Change-Id: Ie7ac7f7fe137e6d99fb178e14f3d5a0fcae9066c
Reviewed-on: https://chromium-review.googlesource.com/1257944
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Don Garrett <dgarrett@chromium.org>
Reviewed-by: Don Garrett <dgarrett@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>

[modify] https://crrev.com/3dbb2932da86d1e175e39e1f9a57d73609e2d16e/lib/portage_util_unittest.py
[modify] https://crrev.com/3dbb2932da86d1e175e39e1f9a57d73609e2d16e/scripts/cros_mark_as_stable.py
[modify] https://crrev.com/3dbb2932da86d1e175e39e1f9a57d73609e2d16e/lib/portage_util.py

Hopefully fixed, verification builds are running right now.