fix recursive_unitless_eltype for general StaticArrays

Author: ranocha

Project.toml

@@ -29,7 +29,7 @@ FillArrays = "0.11, 0.12, 0.13"
 GPUArraysCore = "0.1"
 IteratorInterfaceExtensions = "1"
 RecipesBase = "0.7, 0.8, 1.0"
-StaticArraysCore = "1"
+StaticArraysCore = "1.1"
 Tables = "1"
 ZygoteRules = "0.2"
 julia = "1.6"

src/utils.jl

@@ -210,13 +210,7 @@ ones has a `Array{Array{Float64,N},N}`, this will return `Array{Float64,N}`.
 recursive_unitless_eltype(a) = recursive_unitless_eltype(eltype(a))
 recursive_unitless_eltype(a::Type{Any}) = Any
 
-# Should be:
-# recursive_unitless_eltype(a::Type{T}) where {T<:StaticArray} = similar_type(a,recursive_unitless_eltype(eltype(a)))
-# But missing from StaticArraysCore
-recursive_unitless_eltype(a::Type{StaticArraysCore.SArray{S, T, N, L}}) where {S, T, N, L} = StaticArraysCore.SArray{S, typeof(one(T)), N, L}
-recursive_unitless_eltype(a::Type{StaticArraysCore.MArray{S, T, N, L}}) where {S, T, N, L} = StaticArraysCore.MArray{S, typeof(one(T)), N, L}
-recursive_unitless_eltype(a::Type{StaticArraysCore.SizedArray{S, T, N, M, TData}}) where {
-                          S, T, N, M, TData} = StaticArraysCore.SizedArray{S, typeof(one(T)), N, M, TData}
+recursive_unitless_eltype(a::Type{T}) where {T<:StaticArraysCore.StaticArray} = StaticArraysCore.similar_type(a, recursive_unitless_eltype(eltype(a)))
 
 recursive_unitless_eltype(a::Type{T}) where {T<:Array} = Array{recursive_unitless_eltype(eltype(a)),ndims(a)}
 recursive_unitless_eltype(a::Type{T}) where {T<:Number} = typeof(one(eltype(a)))

test/copy_static_array_test.jl

@@ -13,6 +13,7 @@ end
 # Immutable FieldVector
 vec = ImmutableFV(1.,2.)
 a = [vec]
+@test recursive_unitless_eltype(a) == ImmutableFV
 b = zero(a)
 recursivecopy!(b, a)
 @test a[1] == b[1]
@@ -25,6 +26,7 @@ copyat_or_push!(a, 2, b[1])
 # Mutable FieldVector
 vec = MutableFV(1.,2.)
 a = [vec]
+@test recursive_unitless_eltype(a) == MutableFV
 b = zero(a)
 recursivecopy!(b, a)
 @test a[1] == b[1]