Type stabilization of ProductArray (#247)

* type stabilization of ProductArray

* formatting

* new test for ProducteArray

* version bumped

Project.toml

@@ -1,7 +1,7 @@
 name = "Manifolds"
 uuid = "1cead3c2-87b3-11e9-0ccd-23c62b72b94e"
 authors = ["Seth Axen <[email protected]>", "Mateusz Baran <[email protected]>", "Ronny Bergmann <[email protected]>", "Antoine Levitt <[email protected]>"]
-version = "0.4.4"
+version = "0.4.5"
 
 [deps]
 Distributions = "31c24e10-a181-5473-b8eb-7969acd0382f"

src/manifolds/VectorBundle.jl

@@ -918,8 +918,7 @@ function `f` for representing an operation with result in the vector space `fibe
 for manifold `M` on given arguments (passed at a tuple).
 """
 function allocate_result_type(::VectorBundleFibers, f, args::NTuple{N,Any}) where {N}
-    T = typeof(reduce(+, one(number_eltype(eti)) for eti in args))
-    return T
+    return typeof(mapreduce(eti -> one(number_eltype(eti)), +, args))
 end
 
 Base.size(x::FVector) = size(x.data)

src/product_representations.jl

@@ -269,7 +269,8 @@ function Base.:*(
     return ProductArray(ShapeSpec, a * v.data, v.reshapers)
 end
 
-number_eltype(::Type{ProductArray{TM,TData,TV}}) where {TM,TData,TV} = eltype(TData)
+number_eltype(a::ProductArray) = number_eltype(a.data)
+number_eltype(::Type{TPA}) where {TM,TData,TPA<:ProductArray{TM,TData}} = eltype(TData)
 
 function _show_component(io::IO, v; pre = "", head = "")
     sx = sprint(show, "text/plain", v, context = io, sizehint = 0)

test/product_manifold.jl

@@ -2,6 +2,13 @@ include("utils.jl")
 
 struct NotImplementedReshaper <: Manifolds.AbstractReshaper end
 
+function parray(M, x)
+    return Manifolds.ProductArray(
+        Manifolds.ShapeSpecification(Manifolds.StaticReshaper(), M.manifolds...),
+        x,
+    )
+end
+
 @testset "Product manifold" begin
     @test_throws MethodError ProductManifold()
     M1 = Sphere(2)
@@ -422,6 +429,15 @@ struct NotImplementedReshaper <: Manifolds.AbstractReshaper end
         @test submanifold_component(pts[1], Val(1)) === pts[1].parts[1]
         @test submanifold_components(Mse, pts[1]) === pts[1].parts
         @test submanifold_components(pts[1]) === pts[1].parts
+
+        p_inf = parray(Mse, randn(5))
+        @test (@inferred ManifoldsBase.allocate_result_type(
+            Mse,
+            Manifolds.log,
+            (p_inf, p_inf),
+        )) === Float64
+        @test (@inferred number_eltype(typeof(p_inf))) === Float64
+        @test pts_prod[1] .+ fill(1.0, 5) == pts_prod[1] .+ 1.0
     end
 
     @testset "ProductRepr" begin