comparison mercurial/changelog.py @ 47234:616b8f412676

revlogv2: introduce a very basic docket file

This is the first stone toward using a docket file in revlogv2. Right now the
docket is very basic and only store the version number (which is -also- stored
into the index file…) and the other files have fixed name. This new
implementation break transactionally… but they are no test checking
transactionally for revlogv2… So I take this as an opportunity to start small.
They are no usage of revlogv2 outside of tests anyway.

The docket keeps the `.i` naming used by previous version index to preserve a
unique entry point. We could decide to use a different name and look it up
first, or to fully rework this in a future "store" version. However that does
not seems necessary right now.

We will re-introduces transactionality (and associated testing…) in a later
changesets.


A long list of TODOs have been added to the relevant comment.

Differential Revision: https://phab.mercurial-scm.org/D10624

47233:bcafcd779d2e

        self._filteredrevs = val
        self._filteredrevs_hashcache = {}

    def delayupdate(self, tr):
        """delay visibility of index updates to other readers"""

        if not self._delayed:
            if len(self) == 0:
                self._divert = True
                if self._realopener.exists(self._indexfile + b'.a'):

47234:616b8f412676

        self._filteredrevs = val
        self._filteredrevs_hashcache = {}

    def delayupdate(self, tr):
        """delay visibility of index updates to other readers"""
        if self._docket is not None:
            return

        if not self._delayed:
            if len(self) == 0:
                self._divert = True
                if self._realopener.exists(self._indexfile + b'.a'):