AST changes when formatting type applications

[ocharles]

The following

foo = bar @'Bar

Gets reformatted to

foo = bar @ 'Bar

I can't reproduce this on https://ormolu-live.tweag.io/, so think it might be a Fourmolu specific bug.

[georgefst]

Thanks. That's odd. I can't think of anything relevant that we alter from Ormolu here. And I'm quite surprised this isn't caught be our test suite.

[georgefst]

I've tried Ormolu 0.5 and Fourmolu 0.7, both built with the same ghc-lib-parser and can observe a difference.

Enabling/disabling DataKinds or TypeApplications doesn't change anything.

[ocharles]

@georgefst Just to clarify, do you mean you can reproduce this bug with Ormolu as well? (Also, hi, isn't it funny that I was adamant I hate autoformatting at ZuriHac, and here I am weeks later, auto-formatting 😝 Great job to all of you with Fourmolu - I'm happy with it!)

[georgefst]

I mean I can reproduce with Fourmolu but not Ormolu.

@brandonchinn178 Any ideas? A bad merge somewhere?

[brandonchinn178]

Possibly. I looked at Meat/Value.hs at the AppType section, but it looked the same on both ends. Will probably need good ol' debugging work

[georgefst]

Also, hi, isn't it funny that I was adamant I hate autoformatting at ZuriHac, and here I am weeks later, auto-formatting

Ha, yeah, glad to have changed your mind.

I don't think I actually caught your name at the time, and only realised who you were a few days later when something about reactive-banana came up and I realised you were the maintainer (I recognise you from a few things e.g. we use your Nix Buildkite plugin at work)!

[ocharles]

Yes, ZuriHac needs bigger name badges 😆

[ocharles]

If it helps, this only happens when using quoted constructors - e.g., foo @True is fine, foo @'True is problematic.

[SeungheonOh]

I found out putting a ticked type inside of parenthesis makes parser happy again.

-- Unhappy parser
id @'Int

-- Happy parser
id @('Int)

It's quite annoying workaround for -Wunticked-promoted-constructors... I hope it get fixed.

[elland]

Is this still being worked on?

[brandonchinn178]

No one's working on it yet. Feel free to open a PR

[brandonchinn178]

Looks like a bad merge 😢

Ormolu fixed this back in 0.1.4.0: tweag/ormolu@286afb7#diff-88777f1040ac8f0f2e2903f2db73e3604774239dff0453bc9fcb68c6ceab1f66

I merged this into Fourmolu as one of my first contributions, and this was before Fourmolu was systematically merging Ormolu changes in, so it was a huge change that I probably overlooked this conflict.
948e32d

I'll make the change (and add a regression test cuz why not)

[SeungheonOh]

Thank you for the fix! Can I know when this bugfix will be released?

[brandonchinn178]

I'm hoping to get #245 merged in for the next release, so maybe in the next week or so?

[brandonchinn178]

Released v0.9.0.0

[SeungheonOh]

Awesome!