Add reverse for SArray and MArray (#910)

* Reverse for SArray and MArray

* fix test on older julia versions

* define reverse for StaticArrays

* version bump to v1.2.1

Author: jishnub

Project.toml

@@ -1,6 +1,6 @@
 name = "StaticArrays"
 uuid = "90137ffa-7385-5640-81b9-e52037218182"
-version = "1.2.0"
+version = "1.2.1"
 
 [deps]
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"

src/abstractarray.jl

@@ -209,10 +209,11 @@ reshape(a::Array, ::Size{S}) where {S} = SizedArray{Tuple{S...}}(a)
 @inline copy(a::StaticArray) = typeof(a)(Tuple(a))
 @inline copy(a::SizedArray) = typeof(a)(copy(a.data))
 
-@inline reverse(v::StaticVector) = typeof(v)(_reverse(v))
+@inline reverse(v::StaticArray) = typeof(v)(_reverse(v))
 
-@generated function _reverse(v::StaticVector{N,T}) where {N,T}
-    return Expr(:tuple, (:(v[$i]) for i = N:(-1):1)...)
+@generated function _reverse(v::StaticArray{N}) where {N}
+    L = tuple_prod(N)
+    return Expr(:tuple, (:(v[$i]) for i = L:(-1):1)...)
 end
 
 @generated function Base.rot180(A::SMatrix{M,N}) where {M,N}

test/MMatrix.jl

@@ -91,6 +91,8 @@
         @test size(typeof(m), 2) === 2
 
         @test length(m) === 4
+
+        @test reverse(m) == reverse(reverse(collect(m), dims = 2), dims = 1)
     end
 
     @testset "setindex!" begin

test/MVector.jl

@@ -71,6 +71,8 @@
         @test size(typeof(v), 2) === 1
 
         @test length(v) === 3
+
+        @test reverse(v) == reverse(collect(v), dims = 1)
     end
 
     @testset "setindex!" begin

test/SArray.jl

@@ -149,6 +149,8 @@
         @test (@inferred view(m, CartesianIndex(1, 1))) === Scalar(m[1, 1])
         @test (@inferred view(m, CartesianIndex(1, 1, 1))) === Scalar(m[1, 1])
         @test (@inferred view(m, 1, 1, CartesianIndex(1))) === Scalar(m[1, 1])
+
+        @test reverse(m) == reverse(reverse(collect(m), dims = 2), dims = 1)
     end
 
     @testset "promotion" begin

test/SMatrix.jl

@@ -108,5 +108,7 @@
         @test length(m) === 4
 
         @test_throws Exception m[1] = 1
+
+        @test reverse(m) == reverse(reverse(collect(m), dims = 2), dims = 1)
     end
 end

test/SVector.jl

@@ -90,6 +90,8 @@
         @test (@inferred view(v, 1, CartesianIndex(1))) === Scalar(v[1])
         @test (@inferred view(v, SVector{2,Int}(1,2))) === @SArray [11, 12]
         @test (@inferred view(v, SOneTo(2))) === @SArray [11, 12]
+
+        @test reverse(v) == reverse(collect(v), dims = 1)
     end
 
     @testset "CartesianIndex" begin

test/SizedArray.jl

@@ -234,6 +234,11 @@
         @test isa(x5, SizedArray{Tuple{24},Float64,1,1,<:SubArray{Float64,1}})
         @test x5 == view(Array(x5), :)
     end
+
+    @testset "reverse" begin
+        x = SizedArray{Tuple{4,3,2}}(rand(4, 3, 2))
+        @test reverse(x) == reverse(reverse(reverse(collect(x), dims = 3), dims = 2), dims = 1)
+    end
 end
 
 struct OVector <: AbstractVector{Int} end