bug#25190: Initialization of `dired-mode-map' in by the `dired-x' feature is not safe

[Lars Ingebrigtsen]

Alexander Shukaev <emacs@Alexander.Shukaev.name> writes:

> consider the two
>
> ;;; KEY BINDINGS.
>
> (define-key dired-mode-map "\C-x\M-o" 'dired-omit-mode)
> (define-key dired-mode-map "*O" 'dired-mark-omitted)

[...]

> sections.  Both can easily fail.  For instance,
>
> (define-key dired-mode-map "%Y" 'dired-do-relsymlink-regexp)
>
> assumes that the "%" prefix command has been defined in
> `dired-mode-map' which is not at all true for any customization.  The 
> `easy-menu-add-item' calls suffers from similar issue.  It should be
> possible to conditionally disable these code sections or even remove 
> them altogether as they are maldesigned.

I've now added some checks to Emacs 27 to ensure that dired-x doesn't
try to define keys in sub-keymaps that doesn't exist.

-- 
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   bloggy blog: http://lars.ingebrigtsen.no