Request textDocument/semanticTokens/full failed.

[Abbath]

Semantic tokens don't work for some of my projects. I don't use stack as in #4583. They work for my other projects.

Your environment

Which OS do you use?

Windows 11

Which version of GHC do you use and how did you install it?

9.6.7 from ghcup

How is your project built (alternative: link to the project)?

https://github.com/Abbath/Calculator

Which LSP client (editor/plugin) do you use?

nvim + nvim-lspconfig, VS Code + Haskell plugin

Which version of HLS do you use and how did you install it?

2.13.0.0 from various sources (ghcup, Mason)

Have you configured HLS in any way (especially: a hie.yaml file)?

Semantic tokens are on in neovim/VS Code config. hie.yaml is available in the repo:

cradle:
    multi:
    - path: "dist-newstyle"
      config: { cradle: { none:  } }
    - path: "./Calculator"
      config: 
        cradle:
          cabal:
            - path: "./Calculator/src"
              component: "lib:Calculator"
            - path: "./Calculator/src-exe"
              component: "exe:Calculator"
            - path: "./Calculator/src-test"
              component: "test:Test"

Steps to reproduce

Open this file in the editor https://github.com/Abbath/Calculator/blob/master/Calculator/src/Calculator.hs

Expected behaviour

Semantic tokens work

Actual behaviour

Semantic tokens do not work

Debug information

2026-04-07T22:05:19.110837Z | Warning | semanticTokens: no HieAst exist for fileNormalizedFilePath "C:\\Code\\Calculator\\Calculator\\src\\Calculator.hs"
[Error - 12:05:19 AM] Request textDocument/semanticTokens/full failed.
  Message: semanticTokens: Rule Failed: GetSemanticTokens
  Code: -32803 

[fendor]

Thank you for the bug report!

cc @soulomoon

[Abbath]

Found the culprit. {-# LANGUAGE CPP #-} breaks it even if not being used.

[soulomoon]

how {-# LANGUAGE CPP #-} stole the HieAst. I'll take a look

[soulomoon]

won't build
ghc 9.6.7, cabal 3.16.1.0, from ghcup

cabal v2-repl --keep-temp-files --enable-multi-repl lib:Calculator 
...
[ 6 of 15] Compiling Network.Wreq.Internal.AWS ( Network/Wreq/Internal/AWS.hs, dist/build/Network/Wreq/Internal/AWS.o, dist/build/Network/Wreq/Internal/AWS.dyn_o )

Network/Wreq/Internal/AWS.hs:135:17: error: [GHC-39999]
    • No instance for ‘memory-0.18.0:Data.ByteArray.Types.ByteArrayAccess
                         (CT.Digest CT.SHA256)’
        arising from a use of ‘convert’
    • In the expression: convert (hmacGetDigest h)
      In an equation for ‘hmac'’:
          hmac' s k
            = convert (hmacGetDigest h)
            where
                h = hmac k s :: (HMAC CT.SHA256)
      In an equation for ‘signRequestV4’:
          signRequestV4 key secret serviceRegion request
            = do !ts <- timestamp
                 let origHost = ...
                     ....
                 let encodePath p = ...
                 ....
            where
                lowerCI = S.map toLower . CI.original
                trimHeaderValue = id
                timestamp
                  = render <$> getCurrentTime
                  where
                      render
                        = S.pack
                            . formatTime defaultTimeLocale "%Y%m%dT%H%M%SZ"
                                . utcToLocalTime utc
                hmac' :: S.ByteString -> S.ByteString -> S.ByteString
                ....
    |
135 |     hmac' s k = convert (hmacGetDigest h)
...
[12 of 15] Compiling Paths_wreq       ( dist/build/autogen/Paths_wreq.hs, dist/build/Paths_wreq.o, dist/build/Paths_wreq.dyn_o )
Error: [Cabal-7125]
Failed to build wreq-0.5.4.4 (which is required by Calculator-15.3.0). See the build log above for details.

[Abbath]

Yes, happened to me too (haskell/wreq#164). You should cabal update and it will take wreq-0.5.4.5 which fixes the issue.

[Abbath]

I've removed that CPP in the latest commit of Calculator but semantic tokens still don't work in files that use CPP. For example https://github.com/Abbath/Calculator/blob/master/Calculator/src-exe/Main.hs

[soulomoon]

works in aarch64 with ghc 9.6.7, cabal 3.16.1.0, from ghcup.

I wonder if scecific cpp break the generation of hieAst

[Abbath]

I have tested with GHC 9.6.7 on amd64 Linux with both Cabal 3.14.2 and 3.16.1. Works just fine. I'm afraid it might be a Windows-only problem. How do I debug this?