contrib/hgperf

py3: introduce a wrapper for __builtins__.{raw_,}input()

In order to make this work, we have to wrap the io streams in a
TextIOWrapper so that __builtins__.input() can do unicode IO on Python
3. We can't just restore the original (unicode) sys.std* because we
might be running a cmdserver, and if we blindly restore sys.* to the
original values then we end up breaking the cmdserver. Sadly,
TextIOWrapper tries to close the underlying stream during its __del__,
so we have to make a sublcass to prevent that.

If you see errors like:

TypeError: a bytes-like object is required, not 'str'

On an input() or print() call on Python 3, the substitution of
sys.std* is probably the root cause.

A previous version of this change tried to put the bytesinput() method
in pycompat - it turns out we need to do some encoding handling, so we
have to be in a higher layer that's allowed to use
mercurial.encoding.encoding. As a result, this is in util for now,
with the TextIOWrapper subclass hiding in encoding.py. I'm not sure of
a better place for the time being.

Differential Revision: https://phab.mercurial-scm.org/D299

#!/usr/bin/env python
#
# hgperf - measure performance of Mercurial commands
#
# Copyright 2014 Matt Mackall <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''measure performance of Mercurial commands

Using ``hgperf`` instead of ``hg`` measures performance of the target
Mercurial command. For example, the execution below measures
performance of :hg:`heads --topo`::

    $ hgperf heads --topo

All command output via ``ui`` is suppressed, and just measurement
result is displayed: see also "perf" extension in "contrib".

Costs of processing before dispatching to the command function like
below are not measured::

    - parsing command line (e.g. option validity check)
    - reading configuration files in

But ``pre-`` and ``post-`` hook invocation for the target command is
measured, even though these are invoked before or after dispatching to
the command function, because these may be required to repeat
execution of the target command correctly.
'''

import os
import sys

libdir = '@LIBDIR@'

if libdir != '@' 'LIBDIR' '@':
    if not os.path.isabs(libdir):
        libdir = os.path.join(os.path.dirname(os.path.realpath(__file__)),
                              libdir)
        libdir = os.path.abspath(libdir)
    sys.path.insert(0, libdir)

# enable importing on demand to reduce startup time
try:
    from mercurial import demandimport; demandimport.enable()
except ImportError:
    import sys
    sys.stderr.write("abort: couldn't find mercurial libraries in [%s]\n" %
                     ' '.join(sys.path))
    sys.stderr.write("(check your install and PYTHONPATH)\n")
    sys.exit(-1)

import mercurial.util
import mercurial.dispatch

def timer(func, title=None):
    results = []
    begin = mercurial.util.timer()
    count = 0
    while True:
        ostart = os.times()
        cstart = mercurial.util.timer()
        r = func()
        cstop = mercurial.util.timer()
        ostop = os.times()
        count += 1
        a, b = ostart, ostop
        results.append((cstop - cstart, b[0] - a[0], b[1]-a[1]))
        if cstop - begin > 3 and count >= 100:
            break
        if cstop - begin > 10 and count >= 3:
            break
    if title:
        sys.stderr.write("! %s\n" % title)
    if r:
        sys.stderr.write("! result: %s\n" % r)
    m = min(results)
    sys.stderr.write("! wall %f comb %f user %f sys %f (best of %d)\n"
                     % (m[0], m[1] + m[2], m[1], m[2], count))

orgruncommand = mercurial.dispatch.runcommand

def runcommand(lui, repo, cmd, fullargs, ui, options, d, cmdpats, cmdoptions):
    ui.pushbuffer()
    lui.pushbuffer()
    timer(lambda : orgruncommand(lui, repo, cmd, fullargs, ui,
                                 options, d, cmdpats, cmdoptions))
    ui.popbuffer()
    lui.popbuffer()

mercurial.dispatch.runcommand = runcommand

for fp in (sys.stdin, sys.stdout, sys.stderr):
    mercurial.util.setbinary(fp)

mercurial.dispatch.run()