LSP Mk II

[ChrisPenner]

Overview

This adds the following features to the Mk I release:

• code actions
  • resolving ambiguous name errors
  • type-directed _hole fille
• rudimentary code folding (into the signature line)
• cancel request handler (e.g. canceling a hover)
• Fixes spurious errors in the ucm shell when hovering over whitespace in vscode #3419

Installation and setup

Currently the only supported configuration is to connect to the LSP via a specified port.

The default is 127.0.0.1:5757, but you can change the port using UNISON_LSP_PORT=1234.

I've got this configuration in my CocConfig for nvim, your setup may vary.

  "languageserver": {
    "unison": {
      "filetypes": ["unison"],
      "host": "127.0.0.1",
      "port": 5757
    }

Note that you'll need to start UCM before you try connecting to it in your editor or your editor might give up (fixed in VS code now 😄 )

For VSCode I believe we'll have to publish an npm package to make an extension.

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This change is 

[ChrisPenner]

Rather than analyze the notes from scratch each time for diagnostics, we should analyze the notes once and collect all the info we can from them. So most of this logic just moved to FileAnalysis.hs