diff --git a/test/test_blockarraysext.jl b/test/test_blockarraysext.jl
index 7c22cf5..2e1b843 100644
--- a/test/test_blockarraysext.jl
+++ b/test/test_blockarraysext.jl
@@ -5,6 +5,7 @@ using Test: @test, @testset
 
 @testset "NamedDimsArraysBlockArraysExt" begin
   elt = Float64
+
   a = BlockSparseArray{elt}([2, 3], [2, 3])
   a[Block(2, 1)] = randn(elt, 3, 2)
   a[Block(1, 2)] = randn(elt, 2, 3)
@@ -18,4 +19,16 @@ using Test: @test, @testset
   @test dename(n[i[Block.(1:2)], j[Block(1)]]) == a[Block.(1:2), Block(1)]
   @test dename(n[Block.(1:2), Block(1)]) == a[Block.(1:2), Block(1)]
   @test dename(n[Block.(1:2), Block.(1:2)]) == a[Block.(1:2), Block.(1:2)]
+
+  a = BlockSparseArray{elt}([2, 3], [2, 3])
+  a[Block(2, 1)] = randn(elt, 3, 2)
+  a[Block(1, 2)] = randn(elt, 2, 3)
+  b = BlockSparseArray{elt}([2, 3], [2, 3])
+  b[Block(2, 1)] = randn(elt, 3, 2)
+  b[Block(1, 2)] = randn(elt, 2, 3)
+  na = nameddimsarray(a, ("i", "j"))
+  nb = nameddimsarray(b, ("j", "i"))
+  nc = na .+ 2 .* nb
+  c = a + 2 * permutedims(b, (2, 1))
+  @test dename(nc, ("i", "j")) ≈ c
 end