No prefixes matched

[noughtmare]

Your environment

Which OS do you use?

NixOS

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

9.4.5 from nixpkgs

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

with cabal, see https://github.com/noughtmare/gigaparsec

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

VS Codium+vscode-haskell

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

haskell-language-server version: 1.10.0.0 (GHC: 9.4.5) (PATH: /nix/store/g3mjflh04dizbfgzq0rp6k61sjq6ggp4-haskell-language-server-1.10.0.0/bin/haskell-language-server-wrapper)
From nixpkgs

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

No

Steps to reproduce

optionally: nix-shell -p haskell.compiler.ghc945 haskell.packages.ghc945.haskell-language-server

git clone https://github.com/noughtmare/gigaparsec.git
cd gigaparsec
git checkout 9b41b8b1c1e945599b72bad9166eca401f9c71d0
codium . -n -g experiments/Experiment2.hs

Unfortunately, I wasn't able to reproduce this on an even smaller project.

Expected behaviour

No prefix matching errors.

Actual behaviour

Multi Cradle: No prefixes matched
pwd: /home/user/haskell/gigaparsec
filepath: /home/user/haskell/gigaparsec/experiments/Experiment2.hs
prefixes:
("src",Cabal {component = Just "lib:gigaparsec"})
("examples/Main.hs",Cabal {component = Just "gigaparsec:exe:gpc-examples"})
("tests",Cabal {component = Just "gigaparsec:test:gpc-test"})
("experiments/Experiment1.hs",Cabal {component = Just "gigaparsec:exe:gpc-experiment1"})
("./Experiment2.hs",Cabal {component = Just "gigaparsec:exe:gpc-experiment2"})

Especially that last line seems wrong.

Debug information

Notes

I found out that it works fine if I swap the order of the main-is and hs-source-dirs fields of the gpc-experiment2 component.

[fendor]

Have you tried an explicit hie.yaml with the contents:

cradle:
  cabal:

that should work in all cabal cases.

[noughtmare]

Thanks, that seems to fix the problem as well.

[fendor]

Closing in favour of #3695

[noughtmare]

@fendor I don't think that issue subsumes this. In this case the module location should be known to HLS, because it is listed in the cabal file:

executable gpc-experiment2
    import:           common
    main-is:          Experiment2.hs
    hs-source-dirs:   experiments

The problem seems to be that implicit-hie picks up the wrong location for Experiment2.hs. It should be experiments/Experiment2.hs, not ./Experiment2.hs.

[fendor]

Upstream issue: Avi-D-coder/implicit-hie#1

We aim to migrate away from implicit-hie, or at least generate smarter cradles in the future. That issue at least touches this topic. I will create a meta issue for implicit-hie.