bug#11397: 24.1.50; permanent-local after-change-functions + read-passwd == unusable minibuffer

[Steve Yegge]

Place the following code in a file, e.g. /tmp/hork-emacs.el:

;; begin code to place in file:
(defun my-after-change-function (&rest ignored)
  "Sample no-op after-change function.")

(put 'my-after-change-function 'permanent-local-hook t)

(defun hork-my-minibuffer ()
  (interactive)
  (add-hook 'after-change-functions 'my-after-change-function)
  (read-passwd "Enter some text: ")
  (message "Your minibuffer should now be horked"))
;; end code to place in file

Run emacs -q -l /tmp/hork-emacs.el
Execute M-x hork-my-minibuffer RET <any text> RET

Afterwards, all minibuffer input will be rendered as '.'
characters, as if it were still reading a password.

This does not happen in Emacs 23.

Also note that the bug does not manifest if you simply
evaluate the code above.  It must be loaded from a file,
at least as far as I can tell (though I do not know why.)

One possible fix might be to have `read-passwd' remove
its lambda from `after-change-functions' in the unwind forms.



In GNU Emacs 24.1.50.2 (x86_64-unknown-linux-gnu, GTK+ Version 2.20.1)
 of 2012-04-16 on stevey.kir.corp.google.com
Windowing system distributor `The X.Org Foundation', version 11.0.60900000
Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Fundamental

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> M-x 
r e p o r t - e m <tab> <return>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.

Load-path shadows:
None found.

Features:
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mm-util mail-prsvr mail-utils time-date tooltip ediff-hook vc-hooks
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fringe lisp-mode register page menu-bar rfn-eshadow timer select
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