comparison mercurial/transaction.py @ 23202:ea5af863fbff

transaction: add 'writepending' logic

The contents of the transaction must be flushed to disk before running
a hook. But it must be flushed to a special file so that the normal
reader does not use it. This logic is currently in the changelog only.
We add some facility to register such operations in the transaction
itself.

23201:7e97bf6ee2d6

            opener.chmod(self.journal, createmode & 0666)
            opener.chmod(self.backupjournal, createmode & 0666)

        # hold file generations to be performed on commit
        self._filegenerators = {}

    def __del__(self):
        if self.journal:
            self._abort()

            self._abort()

    def running(self):
        return self.count > 0

    @active
    def close(self):
        '''commit the transaction'''
        if self.count == 1 and self.onclose is not None:
            self._generatefiles()

23202:ea5af863fbff

            opener.chmod(self.journal, createmode & 0666)
            opener.chmod(self.backupjournal, createmode & 0666)

        # hold file generations to be performed on commit
        self._filegenerators = {}
        # hold callbalk to write pending data for hooks
        self._pendingcallback = {}
        # True is any pending data have been written ever
        self._anypending = False

    def __del__(self):
        if self.journal:
            self._abort()

            self._abort()

    def running(self):
        return self.count > 0

    def addpending(self, category, callback):
        """add a callback to be called when the transaction is pending

        Category is a unique identifier to allow overwriting an old callback
        with a newer callback.
        """
        self._pendingcallback[category] = callback

    @active
    def writepending(self):
        '''write pending file to temporary version

        This is used to allow hooks to view a transaction before commit'''
        categories = sorted(self._pendingcallback)
        for cat in categories:
            # remove callback since the data will have been flushed
            any = self._pendingcallback.pop(cat)()
            self._anypending = self._anypending or any
        return self._anypending

    @active
    def close(self):
        '''commit the transaction'''
        if self.count == 1 and self.onclose is not None:
            self._generatefiles()