Update thin to 1.8.0 to fix bundle install error with xcode 12 on MacOS

[dputtick]

Summary

When I attempt to bundle install a fresh set of Rails dependencies, thin (a dependency of blade) fails to build with native extensions. It looks like I'm hitting the issue described in macournoyer/thin#372. The root cause seems to be a change in how Clang 12 treats a specific compiler warning. Updating thin to 1.8.0 fixes the issue, thanks to this change. The 1.7.2 to 1.8.0 diff is non-trivial, but the vast majority of the changes are to specs.

One thing I am a bit confused about: the blade dependency is listed under ActionCable in the Gemfile, but from grepping around it's only used by ActionView. Am I right that it's only used in the ActionView tests? I'm not super familiar with the Rails codebase. I did see the assets:compile ActionView rake task, but since blade isn't included with the packaged gem, it seems like any non-development code that tried to use it would fail.

Other Information

Worth noting if anybody else runs into this issue that there's a temporary fix described in the PR to thin which worked for me. Would nice to get a vanilla bundle install working, though!

[kaspth]

Nice! I just hit this today.

I haven't looked at the blade setup in a while, but it's possible that it was replaced (eith rollup?) and the blade dependency was never removed.

[dputtick]

@kaspth yeah, it looks like blade was added in 2016 to help build the JS bits of ActionCable, but was replaced with Rollup here #34440. It seems ActionView is still using blade to build rails-ujs for pre Rails 6 backport releases, maybe?

[dputtick]

@kaspth I moved the dependencies in the Gemfile for clarity and got rid of blade-sauce_labs_plugin since it wasn't being used anymore. Are you up for reviewing this?

[kaspth]

Are you up for reviewing this?

Yeah, now that it's no longer 1am my time 😂

It seems ActionView is still using blade to build rails-ujs for pre Rails 6 backport releases, maybe?

Rails < 6 won't receive backport fixes anymore with Rails 6.1 incoming and even if so the builds would happen from a separate release branch (like 5-2-stable). What happens if we just remove it?

[dputtick]

Yeah, now that it's no longer 1am my time

@kaspth 😂 oops

After digging a bit more, I was wrong, it turns out blade is still being used for building rails-ujs on Rails 6. So, I think the best option for now is probably to merge this as-is.

[kaspth]

It's past 1am again but what the hell 😂 Thanks for the help!