RhodeCode CE/EE

Supposedly there's a hidden feature

https://rhodecode.tenderapp.com/help/discussions/questions/32935-zip-download-with-subrepos

by which you can download subrepos along with superrepos in one fell swoop... but it's been disabled (according to Marcin).
Marcin says it's a difficult problem (atomicity) and recommended I open this issue. For the record here are relevant excerpts from the bash script we use on my server to simulate this:

#!/bin/bash

set -e

NIGHTLY=0
ROLLBACK=0
if [ x$1 == 'x-n' ]; then
    NIGHTLY=1
fi

REPOS=`cut -d " " -f 2 < .hgsubstate | sort`
REPOS=". $REPOS"

if [ $NIGHTLY == 1 ]; then
    echo "Nightly build - moving all to default tip"
    hg pull
    hg up -C default
    for repo in $REPOS; do      
        hg pull -R $repo
        hg up -C -R $repo default
    done
    if hg commit -m "Nightly temp commit"; then
        echo "Did temporary commit. Will rollback when done."
        ROLLBACK=1
    fi
fi

if [ $ROLLBACK == 1 ]; then
    echo "Rolling back temp commit..."
    hg rollback
    hg up -C
fi