evolve: abort if deciding resolution parent is ambiguous
While solving content-divergence, it could be hard to decide
which cset should be treated as a resolution parent if there
are multiple successors of divergent cset. i.e split case.
But we are planning to make some update in handling this split
case:
1) consider highest one if all splitted csets are in a single
topological branch
2) still need to decide if 1) doesn't apply
#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