cabal-add integration as a CodeAction

[VenInf]

This is a proof-of-concept solution for the issue #3853

If HLS detects a message like "module Bla.Bla.Bla is a member of a hidden package bla-1.2.3" it suggests a quick fix, that finds the closest cabal file and adds the dependency there.

Solution uses Distribution.Client.Add from the cabal-add and automaticly adds version requirement, if it's detected.

CC @Bodigrim

Video with an example:

cabalAddCodeAction.mp4

Implementation details

For now, the cabal-add project was linked using remote package specification. Some parts were heavily inspired by the cabal-add code in the main module and might be rewritten later.

CodeAction works by parsing all haskell diagnostics, and is constructed if a suited message was found. Parsed information is passed down to a new command, which itself uses tools provided by cabal-add. The command conducts IO actions with found cabal file.

What isn't impemented

• automatic tests, and existing ones lack variety (Since the error is not documented it's hard to make it's different versions. Also GHC(?) does not register that .cabal file was changed and still shows error)
• no recorders
• no action for "missing dependencies" error, since I couldn't recreate it
• no multiple packages suggestion

[Bodigrim]

Thanks for working on this!

[VenInf]

Have made some significant changes to the solution.

• Integrated readBuildTargets. It doesn't give all the targets in the cabal file, so the result of the action is similar. But it supports multiple targets, if there will be a way to get them.
• Now sometimes genericPackageDescription is received via cabal rule.There are a lot of IO actions in the solution, and it will be hard/unnecessary(?) to add them all.
• General refactoring

[Bodigrim]

I don't know if HLS does it in other cases, but it could be a good idea to lock the handle using https://hackage.haskell.org/package/lukko-0.1.2/docs/Lukko.html#v:hLock.

[Bodigrim]

Or without lukko, open file for read/write access and manipulate it without closing?.. Or am I talking nonsense?..

[fendor]

Instead of manually reading and parsing, use https://github.com/haskell/haskell-language-server/blob/master/plugins/hls-cabal-plugin/src/Ide/Plugin/Cabal.hs#L260, which hooks into the rule system.

E.g.

liftIO $ runAction "cabal-plugin.cabal-add" ide $ useWithStale ParseCabalFile $ toNormalizedFilePath $ toNormalizedFilePath cabalFilePath

This will give you the GPD already parsed and cached.

[fendor]

Or if you need the fields, the original link will give you that

[VenInf]

Since the handle using approach is not very in the style of hls I used runAction approach instead. It falls back on reading files, if the data wasn't found in rules.

[VenInf]

Have made a lot of changes to the solution:

• Refactoring and fixed some naming issues
• Write to a cabal file was changed to a comprehensive edit
• Added logs
• Tests (Many thanks for helping out with them to the @fendor)
• Others

[VeryMilkyJoe]

Thank you for this awesome feature, I just have a few nitpicks and will check it out and manually test a little bit :)

[fendor]

Very nice, just a couple of changes, then this is fine by me :)

[fendor]

LGTM, a couple nitpicks left 😇

[Bodigrim]

I built HLS from sources, but apparently something is off in my configuration, because when clicking on "Add dependency ..." I keep getting log messages like

haskell-ide-engine: 2024-08-21T22:41:41.162085Z | Warning | No plugin handles this "codeAction/resolve" request.
:: [23:41:41.162] <~~ haskell-ide-engine (124) (duration: 0ms): {'code': -32601, 'message': 'No plugins are available to handle this SMethod_CodeActionResolve request.\n Plugins installed for this method, but not available to handle this request are:\nexplicit-fields does not handle resolve requests for (unable to determine resolve owner)).\nhlint does not handle resolve requests for (unable to determine resolve owner)).\noverloaded-record-dot does not handle resolve requests for (unable to determine resolve owner)).\nimportLens does not handle resolve requests for (unable to determine resolve owner)).'}

Do I need to enable something specific in my HLS config? I put there

			"settings": {
				"haskell.plugin.ghcide-completions.config.snippetsOn": false,
				"haskell.formattingProvider": "fourmolu",
				"haskell.plugin.stan.globalOn": false,
				"haskell.plugin.semanticTokens.globalOn": true,
				"haskell.plugin.cabalHaskellIntegration.globalOn": true,
				"haskell.plugin.cabal.globalOn": true
			},

but seemingly I didn't get plugin name right.

[fendor]

The config shouldn't need any modification as it is disabled by default.
You may have to tell your language server to also send notifications for .cabal files, but I don't know how to do that in non-vscode settings.

I also get errors such:

2024-08-22T08:20:24.550779Z | Warning | No plugin handles this "codeAction/resolve" request.
[Trace - 10:20:24] Received response 'codeAction/resolve - (71)' in 1ms. Request failed: No plugins are available to handle this SMethod_CodeActionResolve request.
 Plugins installed for this method, but not available to handle this request are:
explicit-fields does not handle resolve requests for (unable to determine resolve owner)).
hlint 's feature that handles this request is disabled in your config.
overloaded-record-dot does not handle resolve requests for (unable to determine resolve owner)).
importLens does not handle resolve requests for (unable to determine resolve owner)). (-32601).
[Error - 10:20:24] Request codeAction/resolve failed.
  Message: No plugins are available to handle this SMethod_CodeActionResolve request.
 Plugins installed for this method, but not available to handle this request are:
explicit-fields does not handle resolve requests for (unable to determine resolve owner)).
hlint 's feature that handles this request is disabled in your config.
overloaded-record-dot does not handle resolve requests for (unable to determine resolve owner)).
importLens does not handle resolve requests for (unable to determine resolve owner)).
  Code: -32601 

But it works otherwise fine on my machine after building from source.

Could you post the full logs?