Incorrect "Unused LANGUAGE pragma" warning with typed Template Haskell about hlint

[jhrcek]

I looked into this and it seems that isQuasiQuoteSplice, which is used to recognize TH usage here

hlint/src/Hint/Extensions.hs

Line 428 in b732749

used TemplateHaskell = hasS $ not . isQuasiQuoteSplice

has changed to be more restrictive in recent versions of ghc-lib-praser-ex:
Before GHC 9.6 it included both typed and untyped TH splices, but in ghc >=9.6 it only includes untyped splices:
https://hackage.haskell.org/package/ghc-lib-parser-ex-9.6.0.1/docs/src/Language.Haskell.GhclibParserEx.GHC.Hs.Expr.html#isQuasiQuoteSplice

Compare:
https://hackage.haskell.org/package/ghc-9.4.4/docs/Language-Haskell-Syntax-Expr.html#t:HsSplice
https://hackage.haskell.org/package/ghc-9.6.1/docs/Language-Haskell-Syntax-Expr.html#t:HsUntypedSplice

Not sure how to fix this yet 🤔

EDIT: after banging my head against GHC ast differences I came up with this benign looking fix 😄 #1535

[nitinprakash96]

+1. Facing same issue.

{-# LANGUAGE TemplateHaskell #-}

module Git where

import qualified GitHash as Git

version :: String
version = Git.giHash $$(Git.tGitInfoCwd)

[shayne-fletcher]

not sure this is quite ready to be closed. re-opening while unsure.

[jhrcek]

@shayne-fletcher I think it's safe to close this issue. I tested my fix with both reproducers and can confirm that the false positive is no longer emitted for either.