No check for unnecessary nil check on a map followed by a len check of the same map

[ChrisHines]

Considering staticcheck identifies unnecessary nil checks for slices followed by a len check, I am surprised it doesn’t seem to do the same for maps.

I was just reviewing some code that is essentially:

type obj struct {
    m map[uint64]bool
}

func (o *obj) method() {
    if o.m != nil && len(o.m) > 0 {
        // start goroutine to process elements of `o.m`
    }
}

I was expecting staticcheck to flag the o.m != nil part as unnecessary, but it isn’t.