bug#22300: 25.1.50; Dired -- renaming folders/files to CamelCase/UPPERCASE/lowercase.

[Eli Zaretskii]

> Date: Sun, 03 Jan 2016 12:57:27 -0800
> From: Keith David Bershatsky <esq@lawlist.com>
> 
> On an Emacs build (master branch), using Emacs -Q, I am unable to change 
> files and folders in dired-mode from CamelCase/UPPERCASE/lowercase.
> 
> A folder named `FOO` cannot be changed to `foo` using `dired-do-rename`.
> 
>     Move ‘/Users/HOME/Desktop/FOO’ to ‘/Users/HOME/Desktop/foo/FOO’ failed:
>       (file-error Renaming Invalid argument /Users/HOME/Desktop/FOO 
> /Users/HOME/Desktop/foo/FOO)

Why is it trying to make a directory into a subdirectory of itself?