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
hg init
echo a > a
hg add a
hg commit -m "test" -d "1000000 0"
hg history
hg tag -d "1000000 0" "bleah"
hg history
echo foo >> .hgtags
hg tag -d "1000000 0" "bleah2" || echo "failed"
hg tag -d "1000000 0" -r 0 "bleah2" 1 || echo "failed"
hg revert .hgtags
hg tag -d "1000000 0" -r 0 "bleah0"
hg tag -l -d "1000000 0" "bleah1" 1
cat .hgtags
cat .hg/localtags
hg update 0
hg tag -d "1000000 0" "foobar"
cat .hgtags
cat .hg/localtags
hg tag -l 'xx
newline'
hg tag -l 'xx:xx'
echo % issue 601
python << EOF
f = file('.hg/localtags'); last = f.readlines()[-1][:-1]; f.close()
f = file('.hg/localtags', 'w'); f.write(last); f.close()
EOF
cat .hg/localtags
hg tag -l localnewline
cat .hg/localtags
python << EOF
f = file('.hgtags'); last = f.readlines()[-1][:-1]; f.close()
f = file('.hgtags', 'w'); f.write(last); f.close()
EOF
hg ci -d '1000000 0' -m'broken manual edit of .hgtags'
cat .hgtags
hg tag -d '1000000 0' newline
cat .hgtags