tests: add more verification of output to divergence tests
It's not obvious what the obsmarkers should look like in these tests
and adding them highlights a bug that happens when commit we create to
resolve the divergence doesn't get created because it would be
empty. I also added a few graphlog calls to check that the
divergence-resolution commit is in the right place (has right
parentage).
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Evolve Commands Reference
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.. highlight:: none
amend
-----
.. hghelp:: amend
evolve
------
.. hghelp:: evolve
fold
----
.. hghelp:: fold
metaedit
--------
.. hghelp:: metaedit
next
----
.. hghelp:: next
obslog
------
.. hghelp:: obslog
pdiff
-----
.. hghelp:: pdiff
previous
--------
.. hghelp:: previous
prune
-----
.. hghelp:: prune
pstatus
-------
.. hghelp:: pstatus
split
-----
.. hghelp:: split
touch
-----
.. hghelp:: touch
uncommit
--------
.. hghelp:: uncommit