[ITensors] Extension implementing VectorInterface.jl for ITensors (#1373)

Author: mtfishman

test/test_NDTensorsNamedDimsArraysExt.jl

@@ -0,0 +1,33 @@
+@eval module $(gensym())
+using NDTensors.NamedDimsArrays: NamedDimsArray, dimnames
+using NDTensors: NDTensors
+using Test: @test, @testset
+
+@testset "NDTensorsNamedDimsArraysExt" begin
+  elt = Float64
+
+  a = NamedDimsArray(randn(elt, 2, 2), ("i", "j"))
+  b = NDTensors.similar(a)
+  @test b isa NamedDimsArray{elt}
+  @test eltype(b) === elt
+  @test dimnames(b) == ("i", "j")
+  @test size(b) == (2, 2)
+
+  a = NamedDimsArray(randn(elt, 2, 2), ("i", "j"))
+  b = NDTensors.similar(a, Float32)
+  @test b isa NamedDimsArray{Float32}
+  @test eltype(b) === Float32
+  @test dimnames(b) == ("i", "j")
+  @test size(b) == (2, 2)
+
+  a = NamedDimsArray(randn(elt, 2, 2), ("i", "j"))
+  b = copy(a)
+  α = randn(elt)
+  b = NDTensors.fill!!(b, α)
+  @test b isa NamedDimsArray{elt}
+  @test eltype(b) === elt
+  @test dimnames(b) == ("i", "j")
+  @test size(b) == (2, 2)
+  @test all(==(α), b)
+end
+end