rank: add minimal test
This adds a small test checking the rank computation in the case of a merge.
Differential Revision: https://phab.mercurial-scm.org/D12141
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Check that we can compute and exchange revision rank properly
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$ cat << EOF >> $HGRCPATH
> [format]
> exp-use-changelog-v2=enable-unstable-format-and-corrupt-my-data
> EOF
Test minimal rank computation with merge
$ hg init rank-repo-minimal
$ cd rank-repo-minimal
$ touch 0
$ hg commit -Aqm 0
$ touch 1
$ hg commit -Aqm 1
$ hg update -qr 0
$ touch 2
$ hg commit -Aqm 2
$ hg merge -qr 1
$ hg commit -m 3
$ touch 4
$ hg commit -Aqm 4
$ hg log --graph --template '{rev} {_fast_rank}\n'
@ 4 5
|
o 3 4
|\
| o 2 2
| |
o | 1 2
|/
o 0 1
$ cd ..