No weight defined: auto
Two numbers: 100 200
Two numbers reversed: 200 100
Two keywords: bold normal
Two keywords reversed: normal bold
Number and keyword: normal 700
Number and keyword reversed: 700 normal
Number and keyword again: bold 300
Number and keyword again reversed: 300 bold
Two numbers filling the range: 1 1000
Invalid too many: auto
Invalid relative lighter: auto
Invalid relative bolder: auto
Invalid relative: auto
Invalid out of range: auto