comparison mercurial/changelog.py @ 44496:897f0ce4b484

changelog: change the implementation of `_divertopener`

During a transaction, new data to the changelog index are "diverted". The
previous implementat ways pretty basic, we need something better to be able to
use the changelog vfs fully during transaction. (eg: accessing the vfs options).

Differential Revision: https://phab.mercurial-scm.org/D8185

44495:1376cb1c8e34

    def __exit__(self, *args):
        return self.fp.__exit__(*args)


def _divertopener(opener, target):
    """build an opener that writes in 'target.a' instead of 'target'"""

    def _divert(name, mode=b'r', checkambig=False, **kwargs):
        if name != target:
            return opener(name, mode, **kwargs)
        return opener(name + b".a", mode, **kwargs)

    return _divert


def _delayopener(opener, target, buf):
    """build an opener that stores chunks in 'buf' instead of 'target'"""

44496:897f0ce4b484

    def __exit__(self, *args):
        return self.fp.__exit__(*args)


class _divertopener(object):
    def __init__(self, opener, target):
        self._opener = opener
        self._target = target

    def __call__(self, name, mode=b'r', checkambig=False, **kwargs):
        if name != self._target:
            return self._opener(name, mode, **kwargs)
        return self._opener(name + b".a", mode, **kwargs)

    def __getattr__(self, attr):
        return getattr(self._opener, attr)


def _delayopener(opener, target, buf):
    """build an opener that stores chunks in 'buf' instead of 'target'"""