view tests/test-merge8.t @ 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.

Test for changeset ba7c74081861
(update dirstate correctly for non-branchmerge updates)
  $ hg init a
  $ cd a
  $ echo a > a
  $ hg add a
  $ hg commit -m a
  $ cd ..
  $ hg clone a b
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd a
  $ hg mv a b
  $ hg commit -m move
  $ echo b >> b
  $ hg commit -m b
  $ cd ../b
  $ hg pull ../a
  pulling from ../a
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 1 files
  (run 'hg update' to get a working copy)
  $ hg update
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved

  $ cd ..