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
cp "$TESTDIR"/../contrib/simplemerge .
echo base > base
echo local > local
cat base >> local
cp local orig
cat base > other
echo other >> other
echo '% changing local directly'
python simplemerge local base other && echo "merge succeeded"
cat local
cp orig local
echo '% printing to stdout'
python simplemerge -p local base other
echo ' local:'
cat local
echo '% conflicts'
cp base conflict-local
cp other conflict-other
echo not other >> conflict-local
echo end >> conflict-local
echo end >> conflict-other
python simplemerge -p conflict-local base conflict-other || echo "merge failed"
echo '% --no-minimal'
python simplemerge -p --no-minimal conflict-local base conflict-other
echo '% 1 label'
python simplemerge -p -L foo conflict-local base conflict-other
echo '% 2 labels'
python simplemerge -p -L foo -L bar conflict-local base conflict-other
echo '% too many labels'
python simplemerge -p -L foo -L bar -L baz conflict-local base conflict-other
echo '% binary file'
python -c "f = file('binary-local', 'w'); f.write('\x00'); f.close()"
cat orig >> binary-local
python simplemerge -p binary-local base other
echo '% binary file --text'
python simplemerge -a -p binary-local base other
echo '% help'
python simplemerge --help
echo '% wrong number of arguments'
python simplemerge
echo '% bad option'
python simplemerge --foo -p local base other
exit 0