view hgext/git/gitutil.py @ 45797:5b6c0af021da

utils: helper function to print top memory allocation site

The memorytop function uses Python's tracemalloc module to show the
source lines / backtraces with the largest remaining allocations. This
allows identifying the origins of active memory by placing calls in
strategic locations. Allocations from C extensions will show up as long
as they are using the Python allocators.

Differential Revision: https://phab.mercurial-scm.org/D9236

"""utilities to assist in working with pygit2"""
from __future__ import absolute_import

from mercurial.node import bin, hex, nullid

from mercurial import pycompat

pygit2_module = None


def get_pygit2():
    global pygit2_module
    if pygit2_module is None:
        try:
            import pygit2 as pygit2_module

            pygit2_module.InvalidSpecError
        except (ImportError, AttributeError):
            pass
    return pygit2_module


def togitnode(n):
    """Wrapper to convert a Mercurial binary node to a unicode hexlified node.

    pygit2 and sqlite both need nodes as strings, not bytes.
    """
    assert len(n) == 20
    return pycompat.sysstr(hex(n))


def fromgitnode(n):
    """Opposite of togitnode."""
    assert len(n) == 40
    if pycompat.ispy3:
        return bin(n.encode('ascii'))
    return bin(n)


nullgit = togitnode(nullid)