Regarding Octave's test feature to add a bug number in assert statements and alike (xtests), where is this properly documented? Neither in this mailing-list, manual , nor the wiki  I can find an explanation of the best practices or the feature in general. An example:
%!assert <*44334> (isequal (st, st))
%!assert <44498> (not (isscalar (st)))
To my knowledge, the number makes it an XFail, and the asterisk marks the bug as fixed, and makes it a regression in case of an failure.