SparseMatrixCSC{Float} * Vector{SVector}

General Usage
1

Julia allows me to multiply Matrix{Float} * Vector{SVector} :

using StaticArrays 
A = rand(10,10)
x = rand(SVector{3, Float64}, 10)
A * x

but not a SparseMatrixCSC{Float} * Vector{SVector} :

using SparseArrays, StaticArrays 
B = sprand(10,10, 0.1)
x = rand(SVector{3, Float64}, 10)
B * x

I get the following error:

julia> B * x
ERROR: MethodError: no method matching one(::Type{Any})
Closest candidates are:
  one(::Type{Union{Missing, T}}) where T at missing.jl:87
  one(::BitArray{2}) at bitarray.jl:400
  one(::Missing) at missing.jl:83
  ...
Stacktrace:
 [1] one(::Type{Any}) at ./missing.jl:87
 [2] *(::SparseMatrixCSC{Float64,Int64}, ::Array{SArray{Tuple{3},Float64,1,3},1}) at /Users/ortner/gits/julia11/usr/share/julia/stdlib/v1.1/SparseArrays/src/linalg.jl:53
 [3] top-level scope at none:0

The relevant line numbers are

*(A::SparseMatrixCSC{TA,S}, x::StridedVector{Tx}) where {TA,S,Tx} =
    (T = promote_type(TA, Tx); mul!(similar(x, T, A.m), A, x, one(T), zero(T)))

So I first need to define promote_type for TA = T, Tx = SVector{T}. Then I need to define one for SVector{T}. But even then it doesn’t work because mul! expects numbers:

function mul!(C::StridedVecOrMat, A::SparseMatrixCSC, B::StridedVecOrMat, α::Number, β::Number)
...

Maybe this is typed too strictly?

Would it be worthwhile opening issues in both StaticArrays.jl as well as SparseArrays about these, or is this just too specialised?

Are there any potential problems defining promote_type and one as I envision?