I believe rsrc files are included under the xml umbrella.
Why would they be? There is no overlap in their formats. xml is a pure text representation; a rsrc file is anything but. rsrc files date back to the Lisa (1983); xml was first described in 1997 and adopted by w3c in 1998.
rsrc files are in the sort of arcane ad hoc binary format that the xml founders were rebelling against.
The only reason the comment says "e.g. plist and xml files", calling out plist in addition to xml, is that xml is only one of the four formats that can be used for plist files. (The other three formats are NEXTSTEP (deprecated), bplist, and JSON (new with Lion).) They want to make it clear that plist files in the bplist format (at least) will also be checked.
Not that it would be hard to check a rsrc file. The
RezDet tool will do all the heavy lifting for you.
