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.
adding a
adding b
adding dir.h/foo
adding t.h
adding t/b
adding t/e.h
adding t/x
hg locate a
a
locate succeeded
hg locate NONEXISTENT
locate failed
hg locate
a
b
dir.h/foo
t.h
t/b
t/e.h
t/x
hg locate a
hg locate NONEXISTENT
hg locate relpath:NONEXISTENT
hg locate
b
dir.h/foo
t.h
t/b
t/e.h
t/x
hg locate -r 0 a
a
hg locate -r 0 NONEXISTENT
hg locate -r 0 relpath:NONEXISTENT
hg locate -r 0
a
b
dir.h/foo
t.h
t/b
t/e.h
t/x
% -I/-X with relative path should work
hg locate
b
dir.h/foo
t.h
t/b
t/e.h
t/x
hg locate -I ../t
t/b
t/e.h
t/x
hg locate t/**
t/b
t/e.h
t/x
hg locate b
../b
../t/b
hg locate *.h
../t.h
../t/e.h
hg locate path:t/x
../t/x
hg locate re:.*\.h$
../t.h
../t/e.h
hg locate -r 0 b
../b
../t/b
hg locate -r 0 *.h
../t.h
../t/e.h
hg locate -r 0 path:t/x
../t/x
hg locate -r 0 re:.*\.h$
../t.h
../t/e.h