(cider-javadoc) cannot fetch javadoc for basic Java class such as "java.lang.Integer"

[pw4ever]

Not sure if this is a "cider" or "cider-nrepl" issue.

With helm-mode enabled, (cider-javadoc) only sees (Helm completions for) Clojure var (e.g., conj) but not Java class (e.g., java.lang.Integer) symbols. Try to enter "Integer" or "java.lang.Integer" result in "[no match]."

Relevant code seems to be:
cider-javadoc-handler

(defun cider-javadoc-handler (symbol-name)
"Invoke the nREPL \"info\" op on SYMBOL-NAME if available."
(when symbol-name
(cider-ensure-op-supported "info")
(let* ((info (cider-var-info symbol-name))
(url (nrepl-dict-get info "javadoc")))
(if url
(browse-url (url-encode-url url))
(error "No Javadoc available for %s" symbol-name)))))

cider-javadoc

(defun cider-javadoc (query)
"Browse Javadoc on the Java symbol QUERY at point."
(interactive "P")
(cider-read-symbol-name "Javadoc for: " 'cider-javadoc-handler query))

cider-var-info

(defun cider-var-info (var &optional all)
"Return VAR's info as an alist with list cdrs.
When multiple matching vars are returned you'll be prompted to select one,
unless ALL is truthy."
(when (and var (not (string= var "")))
(let ((var-info (cider-sync-request:info var)))
(if all var-info (cider--var-choice var-info)))))

So it appears that info of symbols like Integer/java.lang.Integer are not passed along from cider-nrepl client.

---

CIDER 0.8.1 (package: 20141123.1045) (Java 1.7.0_71, Clojure 1.6.0, nREPL 0.2.6)

~/.lein/profiles

{
:user { :plugins [[cider/cider-nrepl "0.8.1"]] }
}

(cider-classpath)

[bbatsov]

Yeah, that's a bug. Someone (perhaps me) copied the var completion code in the javadoc handler. I'll have it fixed.

[pw4ever]

@bbatsov
Not to bug you, but could you elaborate it a bit? I remember not long ago, cider-javadoc works. So to me, this looks like a recent thing.

If this is a simple fix, could you outline the fix? If it takes more in-depth fix, perhaps a brief idea where to start?

Really appreciate your time & work.

[bbatsov]

It works properly for a symbol at point, but when there isn't a symbol at point you'll be presented with a list of var names. We should change this to use cider-read-from-minibuffer instead (it's used in cider-read-and-eval). cider-read-from-minibuffer gives you a minibuffer prompt that provides symbol completion with TAB and M-TAB.

[pw4ever]

Indeed, it works when there is symbol at point.

@bbatsov
I have submitted a patch based on your outlined solution via pull request #896. Kindly take a look at it when you have time.

[pw4ever]

Also, I am not familiar with cider and cider-nrepl enough to know this: Do we have "completion" function for Java classes (perhaps furnished by nrepl through (ns-imports *ns*))?

If we have this, we can have something similar to "cider-completing-read-var" for Java classes, e.g., "cider-completing-read-class".