bug#81624: New command: xref-find-by-kind

Dmitry Gutov <[email protected]> writes:

> X-Debbugs-Cc: [email protected], [email protected]
> See the branch 'xref-find-by-kind', feedback welcome!

I've skimmed the diff (on my mobile) and my overall feedback is positive.

One thing I'd like to see address: what to do about

   (defun eglot-find-declaration...
   (defun eglot-find-implementation...
   (defun eglot-find-typeDefinition...

?

I'd like to see them rewritten using new xref.el entry points, but
xref-backend-xrefs-by-kind is just a "get information" entry point
(which is fine).

IIRC I suggested a 'xref-define-finder' macro

   (defmacro xref-define-finder (command kind) ...)

And then that trio of definitions could become

   (xref-define-finder eglot-find-declaration declaration)
   (xref-define-finder eglot-find-implementation implementation)
   (xref-define-finder eglot-find-typeDefinition type-definition)

And go almost exclusively through the same xref code paths as the other
non-eglot-specific entry points and I we could bin that hacky
eglot--lsp-xref-helper, offsetting some of the new complexity addition.

On a less important note

>    * lisp/progmodes/xref.el (xref-find-by-kind): Delete " of" from
>    the identifier prompt.  I've gone back and forth on this - it
>    reads a bit better with Eglot (LSP kinds) but does not fit the
>    Elisp backend.

Heh, if you really wanted to go heroic/ocd you could make new optional
:format key entry in the kind

   (:kind declaration :name "declaration" :key ?d :prompt-format "Find %s of")

Not sure it's worth it, but not very hard to do either, I suppose.

João