#!/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

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)

def perf(revset):

    """run benchmark for this very revset"""

    try:

    except CalledProcessError, exc:

        print >> sys.stderr, 'abort: cannot run revset benchmark'

        sys.exit(exc.returncode)

def printrevision(rev):

    """print data about a revision"""

    sys.stdout.write("Revision: ")

    sys.stdout.flush()

    check_call(['hg', 'log', '--rev', str(rev), '--template',

               '{desc|firstline}\n'])

def getrevs(spec):

    """get the list of rev matched by a revset"""

    try:

        out = check_output(['hg', 'log', '--template={rev}\n', '--rev', spec])

    except CalledProcessError, exc:

        print >> sys.stderr, "abort, can't get revision from %s" % spec

        sys.exit(exc.returncode)

    return [r for r in out.split() if r]

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 = getrevs(target_rev)

for r in revs:

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

    printrevision(r)

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

    update(r)

    for idx, rset in enumerate(revsets):

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