view contrib/perf-utils/discovery-helper.sh @ 42271:0ed293a3f00e

releasenotes: add a file in which to record release notes

I've just spent a few very boring hours going through the changelog
for the 5.0 release (829 commits). We only had 5 commits that used the
syntax that the release notes extension expects. This commit adds a
file in which we can record important changes. The file should
preferably be edited in the patch that makes the important change, but
it can also be edited after (I think this is an important benefit
compared to the release notes extension).

I'm thinking that we can rename the file from "next" to "5.1" or
something when it's time, and then we'd create a new "next" file on
the default branch.

I've used the syntax that we use on the our wiki in the template, but
I don't care much that we use any valid syntax at all. The idea is
mostly to record important changes when they happen. I expect that
some copy editing will be needed at release time anyway.

Differential Revision: https://phab.mercurial-scm.org/D6332

#!/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

printusage () {
     echo "usage: `basename $0` REPO NBHEADS DEPTH [left|right]" >&2
}

if [ $# -lt 3 ]; then
    printusage
    exit 64
fi

repo="$1"
shift

nbheads="$1"
shift

depth="$1"
shift

doleft=1
doright=1
if [ $# -gt 1 ]; then
    printusage
    exit 64
elif [ $# -eq 1 ]; then
    if [ "$1" == "left" ]; then
        doleft=1
        doright=0
    elif [ "$1" == "right" ]; then
        doleft=0
        doright=1
    else
        printusage
        exit 64
    fi
fi

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:'
if [ $doleft -eq 1 ]; then
    echo '# left  revset:' '"'${leftsubset}'"'
fi
if [ $doright -eq 1 ]; then
    echo '# right revset:' '"'${rightsubset}'"'
fi

buildone() {
    side="$1"
    dest="$2"
    revset="$3"
    echo "### building $side repository: $dest"
    if [ -e "$dest" ]; then
        echo "destination repo already exists: $dest" >&2
        exit 1
    fi
    echo '# cloning'
    if ! cp --recursive --reflink=always ${repo} ${dest}; then
        hg clone --noupdate "${repo}" "${dest}"
    fi
    echo '# stripping' '"'${revset}'"'
    hg -R "${dest}" --config extensions.strip= strip --rev "$revset" --no-backup
}

if [ $doleft -eq 1 ]; then
    buildone left "$leftrepo" "$leftsubset"
fi

if [ $doright -eq 1 ]; then
    buildone right "$rightrepo" "$rightsubset"
fi