Use clojure--sym-regexp to detect fully-qualified syms

(not space) was too permissive and would include commas and other punctuation.

Author: yuhan0

cider-util.el

@@ -511,9 +511,11 @@ restore it properly when going back."
     (setq help-xref-stack-item item)))
 
 (defcustom cider-doc-xref-regexp
-  (rx (or (: "`" (group-n 1 (+ (not space))) "`")   ; `var`
+  (eval-and-compile
+    (rx-to-string
+     `(or (: "`" (group-n 1 (+ (not space))) "`")  ; `var`
           (: "[[" (group-n 1 (+ (not space))) "]]") ; [[var]]
-          (group-n 1 (+ (not space)) "/" (+ (not space))))) ; Fully qualified
+          (group-n 1 (regexp ,clojure--sym-regexp) "/" (regexp ,clojure--sym-regexp))))) ;; Fully qualified
   "The regexp used to search Clojure vars in doc buffers."
   :type 'regexp
   :safe #'stringp