Adapted behaviour of ui.username() to documentation and mention it explicitly:
Searched in this order: $HGUSER, [ui] section of hgrcs, $EMAIL
and stop searching if one of these is set.
Abort if found username is an empty string to force specifying
the commit user elsewhere, e.g. with line option or repo hgrc.
If not found, use $LOGNAME or $USERNAME +"@full.hostname".
include hg
recursive-include mercurial *.py
include hgweb.cgi hgwebdir.cgi
include hgeditor rewrite-log
include tests/README tests/run-tests tests/test-*[a-z0-9] tests/*.out
prune tests/*.err
include *.txt
include templates/map templates/map-*[a-z0-9]
include templates/*.tmpl
include doc/README doc/Makefile doc/*.txt doc/*.html doc/*.[0-9]
recursive-include contrib *
include README
include CONTRIBUTORS
include COPYING
include Makefile
include MANIFEST.in