Bug#312206: dpkg-divert deletes a file if it is diverted to itself

[Jim MacBaine <jmacbaine@gmail.com>]

Package: dpkg
Version: 1.10.27
Severity: important

Although I cannot imagine a sane reason to divert a file to itself, I
happened to do this due to a typo in a script.  I do not think there
is a reason for dpkg-divert to delete the diverted file in that case. 
If such a reason exists, maybe one can add a security question and a
--force option for scripts.

host:/lib/modules# find /lib/modules/ | grep isdnloop
/lib/modules/2.6.8-2-686/kernel/drivers/isdn/isdnloop
/lib/modules/2.6.8-2-686/kernel/drivers/isdn/isdnloop/isdnloop.ko

host:/lib/modules# dpkg-divert --rename --divert
/lib/modules/2.6.8-2-686/kernel/drivers/isdn/isdnloop/isdnloop.ko
/lib/modules/2.6.8-2-686/kernel/drivers/isdn/isdnloop/isdnloop.ko
Adding `local diversion of
/lib/modules/2.6.8-2-686/kernel/drivers/isdn/isdnloop/isdnloop.ko to
/lib/modules/2.6.8-2-686/kernel/drivers/isdn/isdnloop/isdnloop.ko'

host:/lib/modules# find /lib/modules/ | grep isdnloop
/lib/modules/2.6.8-2-686/kernel/drivers/isdn/isdnloop

host:/lib/modules# dpkg-divert --remove
/lib/modules/2.6.8-2-686/kernel/drivers/isdn/isdnloop/isdnloop.ko
Removing `local diversion of
/lib/modules/2.6.8-2-686/kernel/drivers/isdn/isdnloop/isdnloop.ko to
/lib/modules/2.6.8-2-686/kernel/drivers/isdn/isdnloop/isdnloop.ko'

host:/lib/modules# find /lib/modules/ | grep isdnloop
/lib/modules/2.6.8-2-686/kernel/drivers/isdn/isdnloop

Regards,
Jim