rewriteutil: allow rewriting merge commits (issue4561)
This patch simply allows rewriteutil.rewrite() to work with commits with
multiple parents (i.e. merges). That function is used in such commands as fold,
metaedit, touch, rewind.
The issue 4561 is marked as easy, the limitation is called unnecessary, no
tests fail after this change. What can go wrong.
#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