'--- tests added 16feb20 after pm#11113014 post ---',
'"failing" (i.e., no transformation) tests',
[ '' => '', ],
[ '*' => '*', ],
[ '*_/' => '*_/', ],
[ ' * _ / ' => ' * _ / ', ],
[ '*fail/' => '*fail/', ],
[ ' * fail / ' => ' * fail / ', ],
'possibly questionable transformations',
[ '__' => '', ],
[ ' __ ' => ' ', ],
[ '__ __' => ' ', ],
[ ' __ __ ' => ' ', ],
[ '____' => '', '???' ],
[ ' ____ ' => ' ', '???' ],
[ '______' => '', '???' ],
[ ' ______ ' => ' ', '???' ],
[ '________' => '', '???' ],
[ ' ________ ' => ' ', '???' ],
[ '__ __ __ __' => ' ', ],
[ ' __ __ __ __ ' => ' ', ],