def delete(self, href=None):
        """Delete an item.

        When ``href`` is ``None``, delete the collection.

        """
        if self.is_fake:
            return

        if href is None:
            self.collection.delete()
            return

        item = self.get(href)
        if item is None:
            raise ComponentNotFoundError(href)

        item.etesync_item.delete()