Fixed an exception in notify extension (b2a_hex argument incorrect) Detailed messages was - incoming.notify hook raised an exception: b2a_hex() argument 1 must be string or read-only character buffer, not stringio

#!/bin/sh

hg init

echo "Is there an error message when trying to diff non-existing files?"
hg diff not found

echo "Is there an error message when trying to add non-existing files?"
hg add not found