Fix allocation on nested power manifold (#153)

Project.toml

@@ -1,7 +1,7 @@
 name = "ManifoldsBase"
 uuid = "3362f125-f0bb-47a3-aa74-596ffd7ef2fb"
 authors = ["Seth Axen <[email protected]>", "Mateusz Baran <[email protected]>", "Ronny Bergmann <[email protected]>", "Antoine Levitt <[email protected]>"]
-version = "0.14.2"
+version = "0.14.3"
 
 [deps]
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"

src/PowerManifold.jl

@@ -148,13 +148,25 @@ function Base.:^(
     return PowerManifold(M, size...)
 end
 
+"""
+    _allocate_access_nested(M::PowerManifoldNested, y, i)
+
+Helper function for `allocate_result` on `PowerManifoldNested`. In allocation `y` can be
+a number in which case `_access_nested` wouldn't work.
+"""
+_allocate_access_nested(M::PowerManifoldNested, y, i) = _access_nested(M, y, i)
+_allocate_access_nested(::PowerManifoldNested, y::Number, i) = y
+
 function allocate_result(M::PowerManifoldNested, f, x...)
     if representation_size(M.manifold) === () && length(x) > 0
         return allocate(M, x[1])
     else
         return [
-            allocate_result(M.manifold, f, map(y -> _access_nested(M, y, i), x)...) for
-            i in get_iterator(M)
+            allocate_result(
+                M.manifold,
+                f,
+                map(y -> _allocate_access_nested(M, y, i), x)...,
+            ) for i in get_iterator(M)
         ]
     end
 end

test/power.jl

@@ -120,6 +120,7 @@ struct TestArrayRepresentation <: AbstractPowerRepresentation end
                 @testset "specific functions" begin
                     @test distance(N, p, q) == sqrt(sum(distance.(Ref(M), p, q) .^ 2))
                     @test exp(N, p, q) == p .+ q
+                    @test exp(N, p, q, 2) == p .+ 2 .* q
 
                     @test retract(N, p, q) == p .+ q
                     @test retract(N, p, q, ExponentialRetraction()) == p .+ q