A request for looking up documentation

[w0rp]

Is there a way to request documentation for something defined in Language Server Protocol? What I'm looking for is something like this.

def foo():
    # Imagine your cursor is on `bar` here, 
    # and you can request documentation for it.
    bar()

I'd like to essentially send a request to look up documentation, and get the documentation text back in a response, such as a docstring for a Python function, or jsdoc text for TypeScript, etc. Currently you can make a "hover" request, but the "hover" request appears to be intended for returning only brief information for a given cursor position, such as short description of a function's signature and a brief summary. It would be nice to be able to separately request full documentation for anything at your cursor.

tsserver does appear to offer full documentation for in its quickinfo request, which is roughly equivalent to hover. https://github.com/Microsoft/TypeScript/blob/master/lib/protocol.d.ts#L1253

[dbaeumer]

This is currently not possible.

[rcjsuen]

I feel this will be difficult to provide in a language-agnostic kind of way due to the different ways a build path can be defined for a language. But perhaps I'm overthinking things here...

[dbaeumer]

@rcjsuen I am not sure I understand your concerns. For hover the server already needs this information.

[mickaelistria]

Currently you can make a "hover" request, but the "hover" request appears to be intended for returning only brief information for a given cursor position, such as short description of a function's signature and a brief summary. It would be nice to be able to separately request full documentation for anything at your cursor.

In JDT-LS (and Eclipse JDT in general), the hover shows the JavaDoc even if it's a long one, and this is still quite usable. What makes you say there is a restriction on the content that's returned by the hover request? Where in the spec is the part that makes hover not fit your use-case?

[dbaeumer]

I think his point is that there is no guarantee that it is always complete.

[rcjsuen]

I am not sure I understand your concerns. For hover the server already needs this information.

I wasn't sure what would be included in the request parameters as I had thought it wouldn't have enough context if you simply arbitrarily gave it a class name and its function (if there were two classes named Person and/or the namespace was ambiguous and so on). However, I realized I missed this bit...

It would be nice to be able to separately request full documentation for anything at your cursor.

So yes, it's basically the same as a hover. Don't mind me... :)

[w0rp]

I think there's no guarantee that a language will support documentation requests. It might make sense to offer documentation requests as an optional feature, with flags for indicating if the server supports the feature, as LSP does already with other features.

I'm not entirely certain if the idea holds water myself. I just think it might be a good idea.