Calling eldoc-message directly

["Clément Pit-Claudel" <cpitclaudel@gmail.com>]

Hi emacs-devel,

The changelog for Emacs 27.1 says "For ElDoc support, you should set 'eldoc-documentation-function' instead of calling 'eldoc-message' directly".

At least one of my packages calls eldoc-message directly, and I'm not sure how to get rid of it.

In that package, I use a server process to get information about the current buffer.  I can use it to asynchronously retrieve documentation about identifiers, among other things.  This pattern seems pretty common (I think that's how tide, elpy, cider, and multiple other modes work).

I currently have an eldoc-documentation-function that sends an asynchronous query, waits for a few milliseconds in the hope to get a quick answer, and otherwise registers a callback that calls eldoc-message directly.  That callback checks that the buffer hasn't been modified and that the point hasn't moved, and if so calls eldoc-message.

Can someone recommend a proper implementation, not based on eldoc-message? (I have vague recollections of a related thread on emacs-devel, but I can't seem to find it)

Thanks,
Clément.