sparse return same: true
sparse: e,<hole>,c,<hole>,a keys=0|2|4|length
one-sided: <hole>,<hole>,b,<hole> keys=2|length
coerced length: d,c,b,a keys=0|1|2|3|length
apply return same: true
apply: z,y,x,w keys=0|1|2|3|length
delete missing source: <hole>,<hole>,a keys=2|length
delete has: false true
null receiver: TypeError
undefined receiver: TypeError
string abc receiver: TypeError
string one: object 1 "a"
string empty: object 0 ""
