# __init__.py - asv benchmark suite

#

# Copyright 2016 Logilab SA <contact@logilab.fr>

#

# This software may be used and distributed according to the terms of the

# GNU General Public License version 2 or any later version.

# "historical portability" policy of contrib/benchmarks:

#

# We have to make this code work correctly with current mercurial stable branch

# and if possible with reasonable cost with early Mercurial versions.

'''ASV (https://asv.readthedocs.io) benchmark suite

Benchmark are parameterized against reference repositories found in the

directory pointed by the REPOS_DIR environment variable.

Invocation example:

    $ export REPOS_DIR=~/hgperf/repos

    # run suite on given revision

    $ asv --config contrib/asv.conf.json run REV

    # run suite on new changesets found in stable and default branch

    $ asv --config contrib/asv.conf.json run NEW

    # display a comparative result table of benchmark results between two given

    # revisions

    $ asv --config contrib/asv.conf.json compare REV1 REV2

    # compute regression detection and generate ASV static website

    $ asv --config contrib/asv.conf.json publish

    # serve the static website

    $ asv --config contrib/asv.conf.json preview

'''

import functools

import os

import re

from mercurial import (

    extensions,

    hg,

    ui as uimod,

)

basedir = os.path.abspath(

    os.path.join(os.path.dirname(__file__), os.path.pardir, os.path.pardir)

)

reposdir = os.environ['REPOS_DIR']

reposnames = [

    name

    for name in os.listdir(reposdir)

    if os.path.isdir(os.path.join(reposdir, name, ".hg"))

]

if not reposnames:

    raise ValueError("No repositories found in $REPO_DIR")

outputre = re.compile(

    (

        r'! wall (\d+.\d+) comb \d+.\d+ user \d+.\d+ sys '

        r'\d+.\d+ \(best of \d+\)'

    )

)

def runperfcommand(reponame, command, *args, **kwargs):

    os.environ["HGRCPATH"] = os.environ.get("ASVHGRCPATH", "")

    # for "historical portability"

    # ui.load() has been available since d83ca85

    if hasattr(uimod.ui, "load"):

        ui = uimod.ui.load()

    else:

        ui = uimod.ui()

    repo = hg.repository(ui, os.path.join(reposdir, reponame))

    perfext = extensions.load(

        ui, 'perfext', os.path.join(basedir, 'contrib', 'perf.py')

    )

    cmd = getattr(perfext, command)

    ui.pushbuffer()

    cmd(ui, repo, *args, **kwargs)

    output = ui.popbuffer()

    match = outputre.search(output)

    if not match:

        raise ValueError("Invalid output {}".format(output))

    return float(match.group(1))

def perfbench(repos=reposnames, name=None, params=None):

    """decorator to declare ASV benchmark based on contrib/perf.py extension

    An ASV benchmark is a python function with the given attributes:

    __name__: should start with track_, time_ or mem_ to be collected by ASV

    params and param_name: parameter matrix to display multiple graphs on the

    same page.

    pretty_name: If defined it's displayed in web-ui instead of __name__

    (useful for revsets)

    the module name is prepended to the benchmark name and displayed as

    "category" in webui.

    Benchmarks are automatically parameterized with repositories found in the

    REPOS_DIR environment variable.

    `params` is the param matrix in the form of a list of tuple

    (param_name, [value0, value1])

    For example [(x, [a, b]), (y, [c, d])] declare benchmarks for

    (a, c), (a, d), (b, c) and (b, d).

    """

    params = list(params or [])

    params.insert(0, ("repo", repos))

    def decorator(func):

        @functools.wraps(func)

        def wrapped(repo, *args):

            def perf(command, *a, **kw):

                return runperfcommand(repo, command, *a, **kw)

            return func(perf, *args)

        wrapped.params = [p[1] for p in params]

        wrapped.param_names = [p[0] for p in params]

        wrapped.pretty_name = name

        return wrapped

    return decorator