evolve: fix content-divergence resolution when p1 is null (issue6201)
Before this fix, in cases like in the added test, the revision number -1 of the
parent was misinterpreted to mean the tipmost revision instead of the null
revision, causing the content-divergence resolution to fail.
$ cat >> $HGRCPATH <<EOF
> [extensions]
> EOF
$ echo "evolve=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/" >> $HGRCPATH
Test outputting version number
$ hg version -v
Mercurial Distributed SCM (version *) (glob)
(see https://mercurial-scm.org for more information)
Copyright (C) 2005-* Matt Mackall and others (glob)
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
Enabled extensions:
evolve external * (glob)
Test install
TODO: fix warning
$ "$PYTHON" "$TESTDIR/../setup.py" install --root "$TESTTMP/installtest" > /dev/null
*/distutils/dist.py:*: UserWarning: Unknown distribution option: 'python_requires' (glob)
warnings.warn(msg)