I think this change broke lint for fbobjc:

PHP Fatal error: Cannot override final method ArcanistFutureLinter::willLintPaths() in /Users/judyliu/Projects/fbobjc/Configurations/Arcanist/lint/linter/FacebookObjcClangFormatLinter.php on line 8

What is ObjcClangFormatLinter overriding willLintPaths() in order to do?

I haven't worked at Facebook since 2011, so I can't access phabricator.fb.com. :)

oh sorry...didn't realize this wasn't internal. n00b X 1000

We basically do

 // Path regexes to run clang-format on
$whitelist = array(
  // '#^BLAH/.*#',
);

foreach ($paths as $path) {
  foreach ($whitelist as $regex) {
    if (preg_match($regex, $path)) {
      $do_lint[] = $path;
    }
  }
}

parent::willLintPaths($do_lint);

There was some reason why we didn't do it in the engine or use other methods...

I don't mind un-final-ing it if that's easiest since this is purely a quality-of-life change, but that does look like stuff that should ideally live somewhere else. Shoot me a diff to remove the problematic final if you want to go that route?

I'm actually revamping our linters and don't think this will be an issue in the future, so let's keep it this way for now. I'll put up a diff if it later becomes an issue.

It would be nice to have a generic way the linters can override what they run on after the engine has decided to run...otherwise you are shoving a lot of logic into the engine.

Hmm, you could do something like this when building a future:

if ($this->shouldLintPath($path)) {
  return new RealFuture(...);
} else {
  return new ImmediateFuture(null);
}

Then in resolveFutures() just return; if the result is null. Basically, lint the path but don't actually do any linting.

The new .arclint files make it easier to flexibly configure linters, although I'm not sure if they're flexible enough for FB. Here's the docs:

https://secure.phabricator.com/book/phabricator/article/arcanist_lint/#configuring-lint

e.g., Phabricator is now configured with this file instead of an engine:

https://secure.phabricator.com/diffusion/P/browse/master/.arclint