topics: add some noise to rewrittent changeset to prevent hash cycle
If we have a changeset with topic `x`, we change it's topic to `y`, fine.
When we change it's topic back again to `x`, we get the hash of the the
obsoleted changeset which had the topic `x` initially. The same happens for few
more cases like clearing the topic of a changeset which initially had no topic.
This approach is influenced from cmdutil.amend and other commands (rebase, histedit, etc…)
#require test-repo
Enable obsolescence to avoid the warning issue when obsmarker are found
$ cat << EOF >> $HGRCPATH
> [experimental]
> evolution=all
> EOF
Go back in the hg repo
$ cd $TESTDIR/..
$ for node in `hg log --rev 'not public() and ::. and not desc("# no-check-commit")' --template '{node|short}\n'`; do
> hg export $node | ${RUNTESTDIR}/../contrib/check-commit > ${TESTTMP}/check-commit.out
> if [ $? -ne 0 ]; then
> echo "Revision $node does not comply with rules"
> echo '------------------------------------------------------'
> cat ${TESTTMP}/check-commit.out
> echo
> fi
> done