tests/test-issue2137.t

convert: also catch missing revlogs when introduced in repo roots

The previous behaviour was almost as if convert.hg.ignoreerrors was always set
for revisions without parents, except that errors were silently ignored. Revlog
errors are handled as a side effect of getcopies(), but getcopies() was only
called when convert.hg.ignoreerrors was set.

Now we always call self.getcopies for root revisions, not only when
convert.hg.ignoreerrors is set, just like we do on all other revisions.
The extra call might be a bit expensive, but the proper fix for that would be
to catch these errors in another way.

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):
  >     def wrapcommit(orig, *args, **kwargs):
  >         result = orig(*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
  > 
  >     extensions.wrapfunction(repo, 'commit', wrapcommit)
  > 
  > 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