The mercurial package seems to contain only : - A python script (hg) - A shell script (hgmerge) - Python .py, .pyc and .pyo files - Templates - Docs - Man pages I see no reason why not add "BuildArch: noarch" to the spec file, nor do I see any indication inside the spec file that this might have been omitted on purpose.
There are a couple of bits that are implemented in C... rpm -ql mercurial |grep so :-)
oops, indeed, I completely missed the two libraries drowned in the python files... sorry for the noise!