tests/test-obsolete-tag-cache.t

manifestdict: extract condition for _intersectfiles() and use for walk()

The condition on which manifestdict.matches() and manifestdict.walk()
take the fast path of iterating over files instead of the manifest, is
slightly different. Specifically, walk() does not take the fast path
for exact matchers and it does not avoid taking the fast path when
there are more than 100 files. Let's extract the condition so we don't
have to maintain it in two places and so walk() can gain these two
missing pieces of the condition (although there seems to be no current
caller of walk() with an exact matcher).

  $ cat >> $HGRCPATH << EOF
  > [extensions]
  > rebase=
  > 
  > [experimental]
  > evolution = createmarkers
  > EOF

Create a repo with some tags

  $ hg init repo
  $ cd repo
  $ echo initial > foo
  $ hg -q commit -A -m initial
  $ hg tag -m 'test tag' test1
  $ echo first > first
  $ hg -q commit -A -m first
  $ hg tag -m 'test2 tag' test2
  $ hg -q up -r 0
  $ echo newhead > newhead
  $ hg commit -A -m newhead
  adding newhead
  created new head

Trigger tags cache population by doing something that accesses tags info

  $ hg log -G -T '{rev}:{node|short} {tags} {desc}\n'
  @  4:042eb6bfcc49 tip newhead
  |
  | o  3:c3cb30f2d2cd  test2 tag
  | |
  | o  2:d75775ffbc6b test2 first
  | |
  | o  1:5f97d42da03f  test tag
  |/
  o  0:55482a6fb4b1 test1 initial
  

  $ cat .hg/cache/tags
  4 042eb6bfcc4909bad84a1cbf6eb1ddf0ab587d41
  3 c3cb30f2d2cd0aae008cc91a07876e3c5131fd22 b3bce87817fe7ac9dca2834366c1d7534c095cf1
  
  55482a6fb4b1881fa8f746fd52cf6f096bb21c89 test1
  d75775ffbc6bca1794d300f5571272879bd280da test2

Create some hidden changesets via a rebase and trigger tags cache
repopulation

  $ hg -q rebase -s 1 -d 4
  $ hg log -G -T '{rev}:{node|short} {tags} {desc}\n'
  o  7:eb610439e10e tip test2 tag
  |
  o  6:7b4af00c3c83  first
  |
  o  5:43ac2a539b3c  test tag
  |
  @  4:042eb6bfcc49  newhead
  |
  o  0:55482a6fb4b1 test1 initial
  

.hgtags filenodes for hidden heads should be visible (issue4550)
(currently broken)

  $ cat .hg/cache/tags
  7 eb610439e10e0c6b296f97b59624c2e24fc59e30 b3bce87817fe7ac9dca2834366c1d7534c095cf1
  
  55482a6fb4b1881fa8f746fd52cf6f096bb21c89 test1
  d75775ffbc6bca1794d300f5571272879bd280da test2