org-element: Fix radio link parser

* lisp/org-element.el (org-element--object-lex): Fix parsing of radio
  links within emphasis.
* testing/lisp/test-org-element.el (test-org-element/link-parser): Add
  test.

Reported-by: R C <recifx@gmail.com>
<http://permalink.gmane.org/gmane.emacs.orgmode/113063>

lisp/org-element.el

@@ -4366,6 +4366,10 @@ to an appropriate container (e.g., a paragraph)."
   (if (memq 'table-cell restriction) (org-element-table-cell-parser)
     (let* ((start (point))
 	   (limit
+	    ;; Object regexp sometimes needs to have a peek at
+	    ;; a character ahead.  Therefore, when there is a hard
+	    ;; limit, make it one more than the true beginning of the
+	    ;; radio target.
 	    (save-excursion
 	      (cond ((not org-target-link-regexp) nil)
 		    ((not (memq 'link restriction)) nil)
@@ -4381,8 +4385,8 @@ to an appropriate container (e.g., a paragraph)."
 		    ((and (= start (1+ (line-beginning-position)))
 			  (= start (match-end 1)))
 		     (and (re-search-forward org-target-link-regexp nil t)
-			  (match-beginning 1)))
-		    (t (match-beginning 1)))))
+			  (1+ (match-beginning 1))))
+		    (t (1+ (match-beginning 1))))))
 	   found)
       (save-excursion
 	(while (and (not found)
@@ -4456,7 +4460,8 @@ to an appropriate container (e.g., a paragraph)."
 			      (org-element-link-parser)))))))
 	    (or (eobp) (forward-char))))
 	(cond (found)
-	      (limit (org-element-link-parser))	;radio link
+	      (limit (forward-char -1)
+		     (org-element-link-parser)) ;radio link
 	      (t nil))))))
 
 (defun org-element--parse-objects (beg end acc restriction &optional parent)

testing/lisp/test-org-element.el

@@ -1618,6 +1618,17 @@ e^{i\\pi}+1=0
    (org-test-with-temp-text "* <<<a>>>\n<point>a-bug"
      (org-update-radio-target-regexp)
      (org-element-parse-buffer)))
+  ;; Pathological case: radio target in an emphasis environment.
+  (should
+   (eq 'bold
+       (org-test-with-temp-text "* <<<radio>>>\n<point>*radio*"
+	 (org-update-radio-target-regexp)
+	 (org-element-type (org-element-context)))))
+  (should
+   (eq 'link
+       (org-test-with-temp-text "* <<<radio>>>\n*<point>radio*"
+	 (org-update-radio-target-regexp)
+	 (org-element-type (org-element-context)))))
   ;; Standard link.
   ;;
   ;; ... with description.