annotate contrib/memory.py @ 49907:58dff81ffba1

typing: add type hints to the common posix/windows platform functions

These are done in sync because some platforms have empty implementations, and it
isn't obvious what the types should be without examining the other.  We want the
types aligned, so @overload definitions that differ aren't generated.  The only
differences here are the few methods that unconditionally raise an error are
marked as `NoReturn`, which doesn't seem to bother pytype.

A couple of the posix module functions needed to be updated with a modern
ternary operator, because pytype seems to want to use the type of the second
object in the old `return x and y` style.

# memory.py - track memory usage
#
# Copyright 2009 Olivia 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.
'''


def memusage(ui):
    """Report memory usage of the current process."""
    result = {'peak': 0, 'rss': 0}
    with open('/proc/self/status', 'r') as status:
        # This will only work on systems with a /proc file system
        # (like Linux).
        for line in status:
            parts = line.split()
            key = parts[0][2:-1].lower()
            if key in result:
                result[key] = int(parts[1])
    ui.write_err(
        ", ".join(
            ["%s: %.1f MiB" % (k, v / 1024.0) for k, v in result.iteritems()]
        )
        + "\n"
    )


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