LSP completions violate spec

[krobelus]

What happened, and what did you expect to happen?

LSP completions include this, which violates the spec because kind should be either "plaintext" or "markdown".

      "documentation": {
        "kind": "",
        "value": ""
      },

documentation is an optional markupContent

go-lsp package defines it as

	// A human-readable string that represents a doc-comment.
	Documentation MarkupContent `json:"documentation,omitempty"`

omitempty is useless. To fix this, we could change it to Documentation *MarkupContent.

Opening this issue here because it seems like https://github.com/nimblebun/go-lsp is not active.
Maybe we should switch to a different library?

Output of "elvish -version"

0.21.0

Code of Conduct

• I agree to follow Elvish's Code of Conduct.

[xiaq]

That's right, we should switch to a more actively maintained LSP type package. Any suggestions?

[krobelus]

I'm not super well informed but I'd probably start with autogenerated message buffers like what gopls uses.
Regarding the issue at hand, they define it as pointer, so the zero value will be serialized correctly

{
    Documentation *Or_CompletionItem_documentation `json:"documentation,omitempty"`
}