Use find-tag-default for xref-backend-identifier-at-point

* lisp/progmodes/etags.el (find-tag-tag)
(tags-completion-at-point-function): Extract common code as
find-tag--default.
(xref-backend-identifier-at-point): Define in terms of the new
function.

1 files changed, 10 insertions, 6 deletions

diff --git a/lisp/progmodes/etags.el b/lisp/progmodes/etags.el
index 6a77b1b2456..2c066df90bc 100644
--- a/lisp/progmodes/etags.el
+++ b/lisp/progmodes/etags.el
@@ -799,9 +799,7 @@ If no tags table is loaded, do nothing and return nil."
     (let ((completion-ignore-case (if (memq tags-case-fold-search '(t nil))
                                       tags-case-fold-search
                                     case-fold-search))
-          (pattern (funcall (or find-tag-default-function
-                                (get major-mode 'find-tag-default-function)
-                                #'find-tag-default)))
+          (pattern (find-tag--default))
           beg)
       (when pattern
         (save-excursion
@@ -818,9 +816,7 @@ If no tags table is loaded, do nothing and return nil."
   (let* ((completion-ignore-case (if (memq tags-case-fold-search '(t nil))
                                      tags-case-fold-search
                                    case-fold-search))
-         (default (funcall (or find-tag-default-function
-                               (get major-mode 'find-tag-default-function)
-                               'find-tag-default)))
+         (default (find-tag--default))
          (spec (completing-read (if default
                                     (format "%s (default %s): "
                                             (substring string 0 (string-match "[ :]+\\'" string))
@@ -832,6 +828,11 @@ If no tags table is loaded, do nothing and return nil."
         (or default (user-error "There is no default tag"))
       spec)))
 
+(defun find-tag--default ()
+  (funcall (or find-tag-default-function
+               (get major-mode 'find-tag-default-function)
+               'find-tag-default)))
+
 (defvar last-tag nil
   "Last tag found by \\[find-tag].")
 
@@ -2084,6 +2085,9 @@ for \\[find-tag] (which see)."
                                                 tag-implicit-name-match-p)
   "Tag order used in `xref-backend-definitions' to look for definitions.")
 
+(cl-defmethod xref-backend-identifier-at-point ((_backend (eql etags)))
+  (find-tag--default))
+
 (cl-defmethod xref-backend-identifier-completion-table ((_backend (eql etags)))
   (tags-lazy-completion-table))