view tests/test-issue2137.t @ 23972:c408bf3b32f8 stable

convert: replace revision references in messages if they are >= short hashes

Convert will try to find references to revisions in commit messages and replace
them with references to the converted revision. It will take any string that
looks like a hash (and thus also decimal numbers) and look it up in the source
repo. If it finds anything, it will use that in the commit message instead.

It would do that for all hex digit sequences of 6 to 40 characters. That was
usually no problem for small repos where it was unlikely that there would be a
matching 6 'digit' hash prefix. It was also no problem on repos with less than
100000 changesets where numbers with 6 or more digits not would match any
revision number. With more than 100000 revisions random numbers in commit
messages would be replaced with a "random" hash. For example, 'handle 100000
requests' would be changed to to 'handle 9117c6 requests'. Convert could thus
not really be used on real repositories with more than 100000 changesets.

The default hash length shown by Mercurial is 12 'digits'. It is unexpected and
unwanted that convert by default tries to replace revision references that use
less than that amount of 'digits'.

To fix this, don't match strings that are less than the default hash size of 12
characters.

http://mercurial.selenic.com/bts/issue2137

Setup:

create a little extension that has 3 side-effects:
1) ensure changelog data is not inlined
2) make revlog to use lazyparser
3) test that repo.lookup() works
1 and 2 are preconditions for the bug; 3 is the bug.

  $ cat > commitwrapper.py <<EOF
  > from mercurial import extensions, node, revlog
  > 
  > def reposetup(ui, repo):
  >     class wraprepo(repo.__class__):
  >         def commit(self, *args, **kwargs):
  >             result = super(wraprepo, self).commit(*args, **kwargs)
  >             tip1 = node.short(repo.changelog.tip())
  >             tip2 = node.short(repo.lookup(tip1))
  >             assert tip1 == tip2
  >             ui.write('new tip: %s\n' % tip1)
  >             return result
  >     repo.__class__ = wraprepo
  > 
  > def extsetup(ui):
  >     revlog._maxinline = 8             # split out 00changelog.d early
  >     revlog._prereadsize = 8           # use revlog.lazyparser
  > EOF

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > commitwrapper = `pwd`/commitwrapper.py
  > EOF

  $ hg init repo1
  $ cd repo1
  $ echo a > a
  $ hg commit -A -m'add a with a long commit message to make the changelog a bit bigger'
  adding a
  new tip: 553596fad57b

Test that new changesets are visible to repo.lookup():

  $ echo a >> a
  $ hg commit -m'one more commit to demonstrate the bug'
  new tip: 799ae3599e0e

  $ hg tip
  changeset:   1:799ae3599e0e
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     one more commit to demonstrate the bug
  

  $ cd ..