tests: add test about aborting content-divergence when multiple parents
This patch adds tests for --abort flag of hg evolve command when we are
resolving content-divergence which are on different parents and parent of one of
them is the gca of both of them.
The tests shows that we are doing good and we should advertise the flag during
conflicts.
#require test-repo
$ checkflake8() {
> if ! (which flake8 > /dev/null); then
> echo skipped: missing tool: flake8;
> exit 80;
> fi;
> };
$ checkflake8
Copied from Mercurial core (60ee2593a270)
$ cd "`dirname "$TESTDIR"`"
run flake8 if it exists; if it doesn't, then just skip
$ hg files -0 'set:(**.py or grep("^#!.*python")) - removed()' \
> -X hgext3rd/evolve/thirdparty \
> 2>/dev/null \
> | xargs -0 flake8