convert: add a mode where mercurial_sink skips empty revisions. The getchanges function of some converter_source classes can return some false positives. I.e. they sometimes claim that a file "foo" was changed in some revision, even though its contents are still the same. convert_svn is particularly bad, but I think this can also happen with convert_cvs and, at least in theory, with mercurial_source. For regular conversions this is not really a problem - as long as getfile returns the right contents, we'll get a converted revision with the right contents. But when we use --filemap, this could lead to superfluous revisions being converted. Instead of fixing every converter_source, I decided to change mercurial_sink to work around this problem. When --filemap is used, we're interested only in revisions that touch some specific files. If a revision doesn't change any of these files, then we're not interested in it (at least for revisions with a single parent; merges are special). For mercurial_sink, we abuse this property and rollback a commit if the manifest text hasn't changed. This avoids duplicating the logic from localrepo.filecommit to detect unchanged files.

#!/bin/sh

mkdir test
cd test
hg init
for i in 0 1 2 3 4 5 6 7 8; do
	echo $i >> foo
	hg commit -A -m $i -d "1000000 0"
done
hg verify
hg serve -p 20059 -d --pid-file=hg.pid
cat hg.pid >> $DAEMON_PIDS
cd ..

hg init new
# http incoming
http_proxy= hg -R new incoming http://localhost:20059/
http_proxy= hg -R new incoming -r 4 http://localhost:20059/
# local incoming
hg -R new incoming test
hg -R new incoming -r 4 test

# test with --bundle
http_proxy= hg -R new incoming --bundle test.hg http://localhost:20059/
hg -R new incoming --bundle test2.hg test

# test the resulting bundles
hg init temp
hg init temp2
hg -R temp unbundle test.hg
hg -R temp2 unbundle test2.hg
hg -R temp tip
hg -R temp2 tip

rm -r temp temp2 new

# test outgoing
hg clone test test-dev
cd test-dev
for i in 9 10 11 12 13; do
	echo $i >> foo
	hg commit -A -m $i -d "1000000 0"
done
hg verify
cd ..
hg -R test-dev outgoing test
http_proxy= hg -R test-dev outgoing http://localhost:20059/
http_proxy= hg -R test-dev outgoing -r 11 http://localhost:20059/