Oddities with the haskell language server

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Currently I am using Emacs as my text editor/IDE of choice. For the past few months I haven’t really been using the Haskell LSP but I decided that, as I start using Haskell for bigger projects I should probably setup a Haskell LSP in order to easily import modules, and to be able to have an easier time using functions from said library.

The GHC installed from my system package manager is broken, so I switched to using GHCUP which works nicely. I also used GHCUP to install the Haskell language server. I setup the lsp-haskell Emacs package. But I am having certain issues.

My LSP doesn’t give completions from

  • other files in the same project
  • installed libraries (both with cabal install and adding as stack/cabal dependencies)
  • sometime none at all unless I am inside of a string for some reason?

It also has a tendency to sometimes crash, though this isn’t too common from what I can tell.
What I did notice is that it recommended functions from MTL. Which I had installed before accidentally breaking GHC.
I was wondering if anyone else has encountered similar issues and/or has a solutions that might help.
Thanks in advance!

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Last time I had to set up HLS outside of Visual Studio Code, I had to make sure that haskell-language-server-wrapper typecheck was working correctly.
In my case, the problem stemmed from HLS not knowing the project root. Since I use cabal, I had to add a file hie.yaml at the root of my project:

> cat hie.yaml
cradle:
  cabal:
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