#!/usr/bin/env python

# Measure the performance of a list of revsets against multiple revisions

# defined by parameter. Checkout one by one and run perfrevset with every

# revset in the list to benchmark its performance.

#

# - First argument is a revset of mercurial own repo to runs against.

# - Second argument is the file from which the revset array will be taken

#   If second argument is omitted read it from standard input

#

# You should run this from the root of your mercurial repository.

#

# This script also does one run of the current version of mercurial installed

# to compare performance.

import sys

from subprocess import check_call, check_output, CalledProcessError

def update(rev):

    """update the repo to a revision"""

    try:

        check_call(['hg', 'update', '--quiet', '--check', str(rev)])

    except CalledProcessError, exc:

        print >> sys.stderr, 'update to revision %s failed, aborting' % rev

        sys.exit(exc.returncode)

target_rev = sys.argv[1]

revsetsfile = sys.stdin

if len(sys.argv) > 2:

    revsetsfile = open(sys.argv[2])

revsets = [l.strip() for l in revsetsfile]

print "Revsets to benchmark"

print "----------------------------"

for idx, rset in enumerate(revsets):

    print "%i) %s" % (idx, rset)

print "----------------------------"

print

revs = check_output("hg log --template='{rev}\n' --rev " + target_rev,

                    shell=True)

revs = [r for r in revs.split() if r]

# Benchmark revisions

for r in revs:

    print "----------------------------"

    sys.stdout.write("Revision: ")

    sys.stdout.flush()

    check_call('hg log -r %s --template "{desc|firstline}\n"' % r, shell=True)

    print "----------------------------"

    update(r)

    for idx, rset in enumerate(revsets):

        sys.stdout.write("%i) " % idx)

        sys.stdout.flush()

    print "----------------------------"