convert: handle past or foreign partial svn copies
Subversion allows revisions to be composed of subparts coming from revisions
before the parent or from other part of the repository. There is no simple
representation for these now, keep the changes but do not track their origins.
6:755d1e0d79e9
5:9ce2ce29723a 3:a3e00c7dbf11 4:bb4475edb621
4:bb4475edb621 1:5d953a1917d1
3:a3e00c7dbf11
2:befc7d89d081
1:5d953a1917d1
0:837088b6e1d9
should work with tag/branch/node/rev
tip^: 5
default^: 5
755d1e0d79e9^: 5
6^: 5
some random lookups
6^^: 3
6^^^: 2
6^^^^: 1
6^^^^^: 0
6^^^^^^: -1
6^1: 5
6^2: abort: unknown revision '6^2'!
6^^2: 4
6^1^2: 4
6^^3: abort: unknown revision '6^^3'!
6~: abort: unknown revision '6~'!
6~1: 5
6~2: 3
6~3: 2
6~4: 1
6~5: 0
6~42: -1
6~1^2: 4
6~1^2~2: 0
with a tag "6^" pointing to rev 1
6^: 1
6^1: 5
6~1: 5
6^^: 3
with a tag "foo^bar" pointing to rev 2
foo^bar: 2
foo^bar^: abort: unknown revision 'foo^bar^'!