contrib/perf-utils/discovery-helper.sh

discovery-helper: reflect argument value in the name of the results

It is common to create multiple pairs of repositories using different argument
values. Recording the argument value in the results names has two main
advantages:

* It is easy to remember the value used to create a pair,
* It get simpler to create multiple pair at the same time from the same source.

Previously, running: `./discovery-helper.sh pypy 50 10` would create a
`pypy-left` and `pypy-right` repository. Now it will create `pypy-50h-10d-left`
and `pypy-50h-10d-right`.

#!/bin/bash
#
# produces two repositories with different common and missing subsets
#
#   $ discovery-helper.sh REPO NBHEADS DEPT
#
# The Goal is to produce two repositories with some common part and some
# exclusive part on each side. Provide a source repository REPO, it will
# produce two repositories REPO-left and REPO-right.
#
# Each repository will be missing some revisions exclusive to NBHEADS of the
# repo topological heads. These heads and revisions exclusive to them (up to
# DEPTH depth) are stripped.
#
# The "left" repository will use the NBHEADS first heads (sorted by
# description). The "right" use the last NBHEADS one.
#
# To find out how many topological heads a repo has, use:
#
#   $ hg heads -t -T '{rev}\n' | wc -l
#
# Example:
#
#  The `pypy-2018-09-01` repository has 192 heads. To produce two repositories
#  with 92 common heads and ~50 exclusive heads on each side.
#
#    $ ./discovery-helper.sh pypy-2018-08-01 50 10

set -euo pipefail

if [ $# -lt 3 ]; then
     echo "usage: `basename $0` REPO NBHEADS DEPTH"
     exit 64
fi

repo="$1"
shift

nbheads="$1"
shift

depth="$1"
shift

leftrepo="${repo}-${nbheads}h-${depth}d-left"
rightrepo="${repo}-${nbheads}h-${depth}d-right"

left="first(sort(heads(all()), 'desc'), $nbheads)"
right="last(sort(heads(all()), 'desc'), $nbheads)"

leftsubset="ancestors($left, $depth) and only($left, heads(all() - $left))"
rightsubset="ancestors($right, $depth) and only($right, heads(all() - $right))"

echo '### creating left/right repositories with missing changesets:'
echo '# left  revset:' '"'${leftsubset}'"'
echo '# right revset:' '"'${rightsubset}'"'

echo '### building left repository:' $left-repo
echo '# cloning'
hg clone --noupdate "${repo}" "${leftrepo}"
echo '# stripping' '"'${leftsubset}'"'
hg -R "${leftrepo}" --config extensions.strip= strip --rev "$leftsubset" --no-backup

echo '### building right repository:' $right-repo
echo '# cloning'
hg clone --noupdate "${repo}" "${rightrepo}"
echo '# stripping:' '"'${rightsubset}'"'
hg -R "${rightrepo}" --config extensions.strip= strip --rev "$rightsubset" --no-backup