(describe-key, describe-key-briefly): For a mouse click,

go to its buffer and position before looking up the key.

diff --git a/lisp/help.el b/lisp/help.el
index d81e433f7551c4cc90d0c5d949e48de1eae2022c..e416fd3d88764006ef25a237078611c59cd79d53 100644 (file)
--- a/lisp/help.el
+++ b/lisp/help.el
@@ -167,12 +167,29 @@ Commands:
     (and (symbolp type)
         (memq 'down (event-modifiers type))
         (read-event)))
-  (let ((defn (key-binding key)))
-    (if (or (null defn) (integerp defn))
-        (message "%s is undefined" (key-description key))
-      (message "%s runs the command %s"
-              (key-description key)
-              (if (symbolp defn) defn (prin1-to-string defn))))))
+  (save-excursion
+    (let ((modifiers (event-modifiers (aref key 0)))
+         window position)
+      ;; For a mouse button event, go to the button it applies to
+      ;; to get the right key bindings.  And go to the right place
+      ;; in case the keymap depends on where you clicked.
+      (if (or (memq 'click modifiers) (memq 'down modifiers)
+             (memq 'drag modifiers))
+         (setq window (posn-window (event-start (aref key 0)))
+               position (posn-point (event-start (aref key 0)))))
+      (if (windowp window)
+         (progn
+           (set-buffer (window-buffer window))
+           (goto-char position)))
+      ;; Ok, now look up the key and name the command.
+      (let ((defn (key-binding key)))
+       (if (or (null defn) (integerp defn))
+           (message "%s is undefined" (key-description key))
+         (message (if (windowp window)
+                      "%s at that spot runs the command %s"
+                    "%s runs the command %s")
+                  (key-description key)
+                  (if (symbolp defn) defn (prin1-to-string defn))))))))
 
 (defun print-help-return-message (&optional function)
   "Display or return message saying how to restore windows after help command.
@@ -255,19 +272,37 @@ If FUNCTION is nil, applies `message' to it, thus printing it."
     (and (symbolp type)
         (memq 'down (event-modifiers type))
         (read-event)))
-  (let ((defn (key-binding key)))
-    (if (or (null defn) (integerp defn))
-        (message "%s is undefined" (key-description key))
-      (with-output-to-temp-buffer "*Help*"
-       (prin1 defn)
-       (princ ":\n")
-       (if (documentation defn)
-           (princ (documentation defn))
-         (princ "not documented"))
-       (save-excursion
-         (set-buffer standard-output)
-         (help-mode))
-       (print-help-return-message)))))
+  (save-excursion
+    (let ((modifiers (event-modifiers (aref key 0)))
+         window position)
+      ;; For a mouse button event, go to the button it applies to
+      ;; to get the right key bindings.  And go to the right place
+      ;; in case the keymap depends on where you clicked.
+      (if (or (memq 'click modifiers) (memq 'down modifiers)
+             (memq 'drag modifiers))
+         (setq window (posn-window (event-start (aref key 0)))
+               position (posn-point (event-start (aref key 0)))))
+      (if (windowp window)
+         (progn
+           (set-buffer (window-buffer window))
+           (goto-char position)))
+      (let ((defn (key-binding key)))
+       (if (or (null defn) (integerp defn))
+           (message "%s is undefined" (key-description key))
+         (with-output-to-temp-buffer "*Help*"
+           (princ (key-description key))
+           (if (windowp window)
+               (princ " at that spot"))
+           (princ " runs the command ")
+           (prin1 defn)
+           (princ ":\n")
+           (if (documentation defn)
+               (princ (documentation defn))
+             (princ "not documented"))
+           (save-excursion
+             (set-buffer standard-output)
+             (help-mode))
+           (print-help-return-message)))))))
 
 (defun describe-mode ()
   "Display documentation of current major mode and minor modes.