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
0: a
hg: unknown command 'an'
Mercurial Distributed SCM
basic commands:
add add the specified files on the next commit
annotate show changeset information per file line
clone make a copy of an existing repository
commit commit the specified files or all outstanding changes
diff diff repository (or selected files)
export dump the header and diffs for one or more changesets
init create a new repository in the given directory
log show revision history of entire repository or files
merge merge working directory with another revision
parents show the parents of the working dir or revision
pull pull changes from the specified source
push push changes to the specified destination
remove remove the specified files on the next commit
revert revert files or dirs to their states as of some revision
serve export the repository via HTTP
status show changed files in the working directory
update update working directory
use "hg help" for the full list of commands or "hg -v" for details
0: a
% should succeed - up is an alias, not an abbreviation
0 files updated, 0 files merged, 0 files removed, 0 files unresolved