amend: allow aborting an `amend --patch` by saving an empty file (issue5925)
This patch fixes issue5925 by allow aborting a `hg amend --patch` call by saving
an empty patch file. This is similar to aborting of `hg amend` when commit
message is empty.
Test changes demonstrate the fix.
#!/bin/sh
. $TESTDIR/testlib/pythonpath.sh
# This file holds logic that is used in many tests.
# It can be called in a test like this:
# $ . "$TESTDIR/testlib/topic_setup.sh"
# Enable obsolete markers and enable extensions
cat >> $HGRCPATH << EOF
[experimental]
evolution=createmarkers,exchange
[extensions]
rebase=
topic=
EOF