Allow clojuredocs navigation on qualified symbols and within *cider-clojuredocs* buffer

[ag91]

This is a feature suggested by user @dotemacs: when we are looking at
clojuredocs, it is often useful to jump to the next related function.

Before this change, cider-clojuredocs could not reach symbols like
true? or clojure.core/map.

Also in buffers with cider-mode enabled we can navigate with the
keybinding C-c C-d C-c. Here I try to support the same also in the
temporary buffer the cider creates for clojuredocs.

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Thanks!

If you're just starting out to hack on CIDER you might find this section of its
manual extremely useful.

[yuhan0]

I don't think this is the right approach -- (thing-at-point 'symbol) works as expected in clojure-mode buffers and doesn't need a separate regex based approach to replace it.
The problem is that the clojuredocs buffer uses the default fundamental-mode syntax table, which doesn't recognize . and ? as symbol constituents.
Executing (set-syntax-table clojure-mode-syntax-table) in the buffer solves the issue.

The question might be whether to apply this more generally to other popups, in cider-make-popup-buffer, or only to
cider-create-clojuredocs-buffer.

[bbatsov]

I'd start small. :-)

And I agree with the rest of your suggestions. In the clojuredocs buffers it might also be a good idea to convert related symbols to links that people can simply press.

[yuhan0]

I was thinking the same thing :)
There's some relevant "See also" button code already implemented at the bottom of cider-docview-render-info.

[ag91]

hey @yuhan0 thanks so much for your comment: I just learned that thing-at-point changes according to the mode AND how to set the syntax table! This PR was just worth the effort for your comment.
@bbatsov maybe I can try to add links in another PR? I am happy to try.

[bbatsov]

Yeah, you can tackle this in separate PR. Thanks!