tests/test-debugindexdot.t
author Siddharth Agarwal <sid0@fb.com>
Fri, 01 Aug 2014 18:30:18 -0700
branchstable
changeset 21990 48e32c2c499b
parent 17490 a03c3ba3e4b5
child 37280 435481393198
permissions -rw-r--r--
context: call normal on the right object dirstate.normal is the method that marks files as unchanged/normal. Rev 20a30cd41d21 started caching dirstate.normal in order to improve performance. However, there was an error in the patch: taking the wlock, under some conditions depending on platform, can cause a new dirstate object to be created. Caching dirstate.normal before calling wlock would then cause the fixup calls below to be on the old dirstate object, effectively disappearing into the ether. On Unix and Unix-like OSes, the condition under which we create a new dirstate object is 'the dirstate file has been modified since the last time we opened it'. This happens pretty rarely, so the object is usually the same -- there's little impact. On Windows, the condition is 'always'. This means files in the lookup state are never marked normal, so the bug has a serious performance impact since all the files in the lookup state are re-read every time hg status is run.

Just exercise debugindexdot
Create a short file history including a merge.
  $ hg init t
  $ cd t
  $ echo a > a
  $ hg ci -qAm t1 -d '0 0'
  $ echo a >> a
  $ hg ci -m t2 -d '1 0'
  $ hg up -qC 0
  $ echo b >> a
  $ hg ci -m t3 -d '2 0'
  created new head
  $ HGMERGE=true hg merge -q
  $ hg ci -m merge -d '3 0'

  $ hg debugindexdot .hg/store/data/a.i
  digraph G {
  	-1 -> 0
  	0 -> 1
  	0 -> 2
  	2 -> 3
  	1 -> 3
  }

  $ cd ..