The WebRTC team is using Elm for an extended project to import a new version of libwebrtc, it would be helpful to be able to use Lando and Phabricator.

Going to get this setup but not yet activate the import til the weekend. The import (based on experience) will probably take ~40 hours or so.

Repo created but not yet importing

https://phabricator.services.mozilla.com/source/elm/

I will do this EOD this Friday.

The import is mostly done, but there are a few revisions failing to import with the following error:

$ ./bin/repository reparse --importing rELM383a2f567cebe59b0212e414b9a27d46123040bf
[2021-09-20 19:58:13] EXCEPTION: (CommandException) Command failed with error #1!
COMMAND
hg --config ui.ssh=/app/phabricator/bin/ssh-connect parents --rev 383a2f567cebe59b0212e414b9a27d46123040bf --style default

STDOUT
(empty)

STDERR
** Unknown exception encountered with possibly-broken third-party extension "differentiator" (version N/A)
** which supports versions 5.5 of Mercurial.
** Please disable "differentiator" and try your action again.
** If that fixes the bug please report it to the extension author.
** Python 3.8.10 (default, May  6 2021, 00:05:59) [GCC 10.2.1 20201203]
** Mercurial Distributed SCM (version 5.7.1)
** Extensions loaded: differentiator
Traceback (most recent call last):
  File "/usr/bin/hg", line 59, in <module>
    dispatch.run()
  File "/usr/lib/python3.8/site-packages/mercurial/dispatch.py", line 143, in run
    status = dispatch(req)
  File "/usr/lib/python3.8/site-packages/mercurial/dispatch.py", line 245, in dispatch
    status = _rundispatch(req)
  File "/usr/lib/python3.8/site-packages/mercurial/dispatch.py", line 289, in _rundispatch
    ret = _runcatch(req) or 0
  File "/usr/lib/python3.8/site-packages/mercurial/dispatch.py", line 465, in _runcatch
    return _callcatch(ui, _runca... (3,885 more bytes) ... at [<arcanist>/src/future/exec/ExecFuture.php:421]
arcanist(head=stable, ref.stable=82660bb58445), moz-extensions(), phabricator()
  #0 ExecFuture::raiseResultError(array) called at [<arcanist>/src/future/exec/ExecFuture.php:325]
  #1 ExecFuture::resolvex() called at [<phabricator>/src/applications/repository/storage/PhabricatorRepository.php:533]
  #2 PhabricatorRepository::execxLocalCommand(string, string) called at [<phabricator>/src/applications/repository/worker/commitchangeparser/PhabricatorRepositoryMercurialCommitChangeParserWorker.php:160]
  #3 PhabricatorRepositoryMercurialCommitChangeParserWorker::parseCommitChanges(PhabricatorRepository, PhabricatorRepositoryCommit) called at [<phabricator>/src/applications/repository/worker/commitchangeparser/PhabricatorRepositoryCommitChangeParserWorker.php:36]
  #4 PhabricatorRepositoryCommitChangeParserWorker::parseCommit(PhabricatorRepository, PhabricatorRepositoryCommit) called at [<phabricator>/src/applications/repository/worker/PhabricatorRepositoryCommitParserWorker.php:72]
  #5 PhabricatorRepositoryCommitParserWorker::doWork() called at [<phabricator>/src/infrastructure/daemon/workers/PhabricatorWorker.php:124]
  #6 PhabricatorWorker::executeTask() called at [<phabricator>/src/infrastructure/daemon/workers/PhabricatorWorker.php:166]
  #7 PhabricatorWorker::scheduleTask(string, array, array) called at [<phabricator>/src/applications/repository/management/PhabricatorRepositoryManagementReparseWorkflow.php:263]
  #8 PhabricatorRepositoryManagementReparseWorkflow::execute(PhutilArgumentParser) called at [<arcanist>/src/parser/argument/PhutilArgumentParser.php:492]
  #9 PhutilArgumentParser::parseWorkflowsFull(array) called at [<arcanist>/src/parser/argument/PhutilArgumentParser.php:377]
  #10 PhutilArgumentParser::parseWorkflows(array) called at [<phabricator>/scripts/repository/manage_repositories.php:22]

After disabling the differentiator extension, reparsing the remaining commits worked fine and the repo is now 100% imported

Reopening this as Lando still needs to be updated to allow merges from this repo.