$ commit()
> {
> msg=$1
> p1=$2
> p2=$3
>
> if [ "$p1" ]; then
> hg up -qC $p1
> fi
>
> if [ "$p2" ]; then
> HGMERGE=true hg merge -q $p2
> fi
>
> echo >> foo
>
> hg commit -qAm "$msg"
> }
$ hg init repo
$ cd repo
$ echo '[extensions]' > .hg/hgrc
$ echo 'parentrevspec =' >> .hg/hgrc
$ commit '0: add foo'
$ commit '1: change foo 1'
$ commit '2: change foo 2a'
$ commit '3: change foo 3a'
$ commit '4: change foo 2b' 1
$ commit '5: merge' 3 4
$ commit '6: change foo again'
$ hg log --template '{rev}:{node|short} {parents}\n'
6:755d1e0d79e9
5:9ce2ce29723a 3:a3e00c7dbf11 4:bb4475edb621
4:bb4475edb621 1:5d953a1917d1
3:a3e00c7dbf11
2:befc7d89d081
1:5d953a1917d1
0:837088b6e1d9
$ echo
$ lookup()
> {
> for rev in "$@"; do
> printf "$rev: "
> hg id -nr $rev
> done
> true
> }
$ tipnode=`hg id -ir tip`
should work with tag/branch/node/rev
$ for r in tip default $tipnode 6; do
> lookup "$r^"
> done
tip^: 5
default^: 5
755d1e0d79e9^: 5
6^: 5
$ echo
some random lookups
$ lookup "6^^" "6^^^" "6^^^^" "6^^^^^" "6^^^^^^" "6^1" "6^2" "6^^2" "6^1^2" "6^^3"
6^^: 3
6^^^: 2
6^^^^: 1
6^^^^^: 0
6^^^^^^: -1
6^1: 5
6^2: abort: unknown revision '6^2'!
6^^2: 4
6^1^2: 4
6^^3: abort: unknown revision '6^^3'!
$ lookup "6~" "6~1" "6~2" "6~3" "6~4" "6~5" "6~42" "6~1^2" "6~1^2~2"
6~: abort: unknown revision '6~'!
6~1: 5
6~2: 3
6~3: 2
6~4: 1
6~5: 0
6~42: -1
6~1^2: 4
6~1^2~2: 0
$ echo
with a tag "6^" pointing to rev 1
$ hg tag -l -r 1 "6^"
$ lookup "6^" "6^1" "6~1" "6^^"
6^: 1
6^1: 5
6~1: 5
6^^: 3
$ echo
with a tag "foo^bar" pointing to rev 2
$ hg tag -l -r 2 "foo^bar"
$ lookup "foo^bar" "foo^bar^"
foo^bar: 2
foo^bar^: abort: unknown revision 'foo^bar^'!