* lisp/subr.el (read-char-choice): Respect help-form. (Bug#9001)

2 files changed, 27 insertions, 17 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 1a2c8daed5b..5efd11e542b 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,6 +1,7 @@
 2011-07-15  Glenn Morris  <rgm@gnu.org>
 
         * subr.el (read-char-choice): Allow quitting.  (Bug#9001)
+        Respect help-form.
 
 2011-07-09  Lawrence Mitchell  <wence@gmx.li>
 
diff --git a/lisp/subr.el b/lisp/subr.el
index d462283b7bd..ef19797012a 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -2145,25 +2145,34 @@ If optional argument INHIBIT-KEYBOARD-QUIT is non-nil, ignore
 keyboard-quit events while waiting for a valid input."
   (unless (consp chars)
     (error "Called `read-char-choice' without valid char choices"))
-  (let (char done)
+  (let (char done show-help (helpbuf " *Char Help*"))
     (let ((cursor-in-echo-area t)
           (executing-kbd-macro executing-kbd-macro))
-      (while (not done)
-        (unless (get-text-property 0 'face prompt)
-          (setq prompt (propertize prompt 'face 'minibuffer-prompt)))
-        (setq char (let ((inhibit-quit inhibit-keyboard-quit))
-                     (read-key prompt)))
-        (cond
-         ((not (numberp char)))
-         ((memq char chars)
-          (setq done t))
-         ((and executing-kbd-macro (= char -1))
-          ;; read-event returns -1 if we are in a kbd macro and
-          ;; there are no more events in the macro.  Attempt to
-          ;; get an event interactively.
-          (setq executing-kbd-macro nil))
-         ((and (not inhibit-keyboard-quit) (eq char ?\C-g))
-          (keyboard-quit)))))
+      (save-window-excursion          ; in case we call help-form-show
+        (while (not done)
+          (unless (get-text-property 0 'face prompt)
+            (setq prompt (propertize prompt 'face 'minibuffer-prompt)))
+          (setq char (let ((inhibit-quit inhibit-keyboard-quit))
+                       (read-key prompt)))
+          (and show-help (buffer-live-p helpbuf)
+               (kill-buffer helpbuf))
+          (cond
+           ((not (numberp char)))
+           ;; If caller has set help-form, that's enough.
+           ;; They don't explicitly have to add help-char to chars.
+           ((and help-form
+                 (eq char help-char)
+                 (setq show-help t)
+                 (help-form-show)))
+           ((memq char chars)
+            (setq done t))
+           ((and executing-kbd-macro (= char -1))
+            ;; read-event returns -1 if we are in a kbd macro and
+            ;; there are no more events in the macro.  Attempt to
+            ;; get an event interactively.
+            (setq executing-kbd-macro nil))
+           ((and (not inhibit-keyboard-quit) (eq char ?\C-g))
+            (keyboard-quit))))))
     ;; Display the question with the answer.  But without cursor-in-echo-area.
     (message "%s%s" prompt (char-to-string char))
     char))