convert: readd --filemap To handle merges correctly, this revision adds a filemap_source class that wraps a converter_source and does the work necessary to calculate the subgraph we're interested in. The wrapped converter_source must provide a new getchangedfiles method that, given a revision rev, and an index N, returns the list of files that are different in rev and its Nth parent. The implementation depends on the ability to skip some revisions and to change the parents field of the commit objects that we returned earlier. To make the conversion restartable, we assume the revisons in the revmapfile are topologically sorted.

adding foo
Patch queue now empty
applying patch1
applying patch2
applying bad-patch
transaction abort!
rollback completed
cleaning up working directory...done
abort: decoding near 'é': 'ascii' codec can't decode byte 0xe9 in position 0: ordinal not in range(128)!
changeset:   0:bbd179dfa0a7
tag:         tip
user:        test
date:        Thu Jan 01 00:00:00 1970 +0000
summary:     add foo

% bar should be gone; other unknown/ignored files should still be around
? untracked-file
I .hgignore
C foo