view hgext/git/gitutil.py @ 49961:7a8bfc05b691

dirstate: rename parentchange to changing_parents

Since the new argument breaks the API anyway, we can rename it to a better name.

The previous name `parentchange` might be seen as something active, a function
that would directly change the parents, however this is just a context manager
to frame the operation that will change the parents and adjust the
dirstate content accordingly.

In addition, the future sister method that will be about changes to tracking and
files would have a hard time fitting in the same naming scheme in a clear way.

The new naming uses a clear prefix will make it more distinct from other
dirstate methods and easier to extend with other similar contexts.

"""utilities to assist in working with pygit2"""

from mercurial.node import bin, sha1nodeconstants

pygit2_module = None


def get_pygit2():
    global pygit2_module
    if pygit2_module is None:
        try:
            import pygit2 as pygit2_module  # pytype: disable=import-error

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


def pygit2_version():
    mod = get_pygit2()
    v = "N/A"

    if mod:
        try:
            v = mod.__version__
        except AttributeError:
            pass

    return b"(pygit2 %s)" % v.encode("utf-8")


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 n.hex()


def fromgitnode(n):
    """Opposite of togitnode."""
    assert len(n) == 40
    return bin(n)


nullgit = togitnode(sha1nodeconstants.nullid)