view tests/revnamesext.py @ 33269:ead6749354e1

phabricator: try to fetch differential revisions in batch

Previously, we read Differential Revisions one by one by calling
`differential.query`.

Fetching them one by one is suboptimal. Unfortunately, there is no Conduit
API that allows us to get a stack of diffids using a single API call.

This patch tries to be smarter using a simple heuristic: when fetching D59
as a stack, previous IDs like D51, D52, D53, ..., D58 are likely belonging
to a same stack so just fetch them as well. Since `differential.query` only
returns cheap metadata without expensive diff content, it shouldn't be a big
problem for the server.

Using a test Phabricator instance, this patch reduces `phabread` reading a
10 patch stack from about 13 to 30 seconds to 8 seconds.

# Dummy extension to define a namespace containing revision names

from __future__ import absolute_import

from mercurial import (
    namespaces,
)

def reposetup(ui, repo):
    names = {'r%d' % rev: repo[rev].node() for rev in repo}
    namemap = lambda r, name: names.get(name)
    nodemap = lambda r, node: ['r%d' % repo[node].rev()]

    ns = namespaces.namespace('revnames', templatename='revname',
                              logname='revname',
                              listnames=lambda r: names.keys(),
                              namemap=namemap, nodemap=nodemap)
    repo.names.addnamespace(ns)