contrib/memory.py

run-tests: capture execution results in a TestResult class

Some implementation details of test execution still live outside of
Test. These include determining what a result means and cleaning up
after the test.

To move to the world where more of this logic can live inside Test or a
derived object, the logic for test execution needs to be refactored.
Specifically, exception trapping and opportunities for result processing
need to be moved into Test.

This patch starts the process by establishing a TestResult class for
holding the results of a test execution. In order to actually use this
class, exception trapping and execution time recording needed to be
moved into Test.run().

# memory.py - track memory usage
#
# Copyright 2009 Matt Mackall <[e-mail]> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''helper extension to measure memory usage

Reads current and peak memory usage from ``/proc/self/status`` and
prints it to ``stderr`` on exit.
'''

import atexit

def memusage(ui):
    """Report memory usage of the current process."""
    status = None
    result = {'peak': 0, 'rss': 0}
    try:
        # This will only work on systems with a /proc file system
        # (like Linux).
        status = open('/proc/self/status', 'r')
        for line in status:
            parts = line.split()
            key = parts[0][2:-1].lower()
            if key in result:
                result[key] = int(parts[1])
    finally:
        if status is not None:
            status.close()
    ui.write_err(", ".join(["%s: %.1f MiB" % (key, value / 1024.0)
                            for key, value in result.iteritems()]) + "\n")

def extsetup(ui):
    atexit.register(memusage, ui)