annotate contrib/plan9/9mail @ 20791:8dd867bd67e1

backout: improve confusing 'cannot backout change on a different branch' abort

These days 'branch' usually refer to a named branch.

Instead, abort with 'cannot backout change that not is an ancestor'.

#!/bin/rc
# 9mail - Mercurial email wrapper for upas/marshal

fn usage {
	echo >[1=2] usage: mercurial/9mail -f from to [cc]
	exit usage
}

from=()
cc=()
to=()

switch($1){
case -f
	from=$2
case *
	usage
}

to=($3)
if(~ $#* 4)
	cc=(-C $4)

upasname=$from
upas/marshal $cc $to