view hgext/largefiles/wirestore.py @ 23529:38e55e55ae4d

largefiles: rewrite merge code using dictionary with entry per file

In overridecalculateupdates(), we currently only deal with conflicts
that result in a 'g' action for either the largefile or a standin. We
will soon want to deal cases with 'cd' and 'dc' actions here. It will
be easier to reason about such cases if we rewrite it using a dict
from filename to action.

A side-effect of this change is that the output can only have one
action per file (which should be a good change). Before this change,
when one of the tests in test-issue3084 received this input (the 'a'
in the input was a result of 'cd' conflict resolved in favor of the
modified file):

  'g': [('.hglf/f', ('',), 'remote created')],
  'a': [('f', None, 'prompt keep')],

and the user chose to keep the local largefile, it produced this
output:


  'g': [('.hglf/f', ('',), 'remote created')],
  'r': [('f', None, 'replaced by standin')],
  'a': [('f', None, 'prompt keep')],

Although 'a' actions are processed after 'r' actions by
recordupdates(), it still worked because 'a' actions have no effect on
merges (only on updates). After this change, the output is:

  'g': [('.hglf/f', ('',), 'remote created')],
  'r': [('f', None, 'replaced by standin')],

Similarly, there are several tests in test-largefiles-update that get
inputs like:

  'a': [('.hglf/large2', None, 'prompt keep')],
  'g': [('large2', ('',), 'remote created')],

and when the user chooses to keep the local largefile, they produce
this output:

  'a': [('.hglf/large2', None, 'prompt keep'),
        ('.hglf/large2', None, 'keep standin')],
  'lfmr': [('large2', None, 'forget non-standin largefile')],

In this case, it was not a merge but an update, so the 'a' action does
have an effect. However, since dirstate.add() is idempotent, it still
has no obserable effect.

After this change, the output is:

  'a': [('.hglf/large2', None, 'keep standin')],
  'lfmr': [('large2', None, 'forget non-standin largefile')],

# Copyright 2010-2011 Fog Creek Software
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''largefile store working over Mercurial's wire protocol'''

import lfutil
import remotestore

class wirestore(remotestore.remotestore):
    def __init__(self, ui, repo, remote):
        cap = remote.capable('largefiles')
        if not cap:
            raise lfutil.storeprotonotcapable([])
        storetypes = cap.split(',')
        if 'serve' not in storetypes:
            raise lfutil.storeprotonotcapable(storetypes)
        self.remote = remote
        super(wirestore, self).__init__(ui, repo, remote.url())

    def _put(self, hash, fd):
        return self.remote.putlfile(hash, fd)

    def _get(self, hash):
        return self.remote.getlfile(hash)

    def _stat(self, hashes):
        '''For each hash, return 0 if it is available, other values if not.
        It is usually 2 if the largefile is missing, but might be 1 the server
        has a corrupted copy.'''
        batch = self.remote.batch()
        futures = {}
        for hash in hashes:
            futures[hash] = batch.statlfile(hash)
        batch.submit()
        retval = {}
        for hash in hashes:
            retval[hash] = futures[hash].value
        return retval