function ValidityBitmap()

in src/arraytypes/arraytypes.jl [204:233]

• 30 lines of code
• 6 McCabe index (conditional complexity)

function ValidityBitmap(x)
    T = eltype(x)
    if !(T >: Missing)
        return ValidityBitmap(UInt8[], 1, length(x), 0)
    end
    len = length(x)
    blen = cld(len, 8)
    bytes = Vector{UInt8}(undef, blen)
    st = iterate(x)
    nc = 0
    b = 0xff
    j = k = 1
    for y in x
        if y === missing
            nc += 1
            b = setbit(b, false, j)
        end
        j += 1
        if j == 9
            @inbounds bytes[k] = b
            b = 0xff
            j = 1
            k += 1
        end
    end
    if j > 1
        bytes[k] = b
    end
    return ValidityBitmap(nc == 0 ? UInt8[] : bytes, 1, nc == 0 ? 0 : len, nc)
end