--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/LazyTensors/lazy_array_test.jl	Sat Feb 20 20:59:32 2021 +0100
@@ -0,0 +1,102 @@
+using Test
+using Sbplib.LazyTensors
+using Sbplib.RegionIndices
+
+
+@testset "LazyArray" begin
+    @testset "LazyConstantArray" begin
+        @test LazyTensors.LazyConstantArray(3,(3,2)) isa LazyArray{Int,2}
+
+        lca = LazyTensors.LazyConstantArray(3.0,(3,2))
+        @test eltype(lca) == Float64
+        @test ndims(lca) == 2
+        @test size(lca) == (3,2)
+        @test lca[2] == 3.0
+    end
+    struct DummyArray{T,D, T1<:AbstractArray{T,D}} <: LazyArray{T,D}
+        data::T1
+    end
+    Base.size(v::DummyArray) = size(v.data)
+    Base.getindex(v::DummyArray{T,D}, I::Vararg{Int,D}) where {T,D} = v.data[I...]
+
+    # Test lazy operations
+    v1 = [1, 2.3, 4]
+    v2 = [1., 2, 3]
+    s = 3.4
+    r_add_v = v1 .+ v2
+    r_sub_v = v1 .- v2
+    r_times_v = v1 .* v2
+    r_div_v = v1 ./ v2
+    r_add_s = v1 .+ s
+    r_sub_s = v1 .- s
+    r_times_s = v1 .* s
+    r_div_s = v1 ./ s
+    @test isa(v1 +̃ v2, LazyArray)
+    @test isa(v1 -̃ v2, LazyArray)
+    @test isa(v1 *̃ v2, LazyArray)
+    @test isa(v1 /̃ v2, LazyArray)
+    @test isa(v1 +̃ s, LazyArray)
+    @test isa(v1 -̃ s, LazyArray)
+    @test isa(v1 *̃ s, LazyArray)
+    @test isa(v1 /̃ s, LazyArray)
+    @test isa(s +̃ v1, LazyArray)
+    @test isa(s -̃ v1, LazyArray)
+    @test isa(s *̃ v1, LazyArray)
+    @test isa(s /̃ v1, LazyArray)
+    for i ∈ eachindex(v1)
+        @test (v1 +̃ v2)[i] == r_add_v[i]
+        @test (v1 -̃ v2)[i] == r_sub_v[i]
+        @test (v1 *̃ v2)[i] == r_times_v[i]
+        @test (v1 /̃ v2)[i] == r_div_v[i]
+        @test (v1 +̃ s)[i] == r_add_s[i]
+        @test (v1 -̃ s)[i] == r_sub_s[i]
+        @test (v1 *̃ s)[i] == r_times_s[i]
+        @test (v1 /̃ s)[i] == r_div_s[i]
+        @test (s +̃ v1)[i] == r_add_s[i]
+        @test (s -̃ v1)[i] == -r_sub_s[i]
+        @test (s *̃ v1)[i] == r_times_s[i]
+        @test (s /̃ v1)[i] == 1/r_div_s[i]
+    end
+    @test_throws BoundsError (v1 +̃  v2)[4]
+    v2 = [1., 2, 3, 4]
+    # Test that size of arrays is asserted when not specified inbounds
+    # TODO: Replace these errors with SizeMismatch
+    @test_throws DimensionMismatch v1 +̃ v2
+
+    # Test operations on LazyArray
+    v1 = DummyArray([1, 2.3, 4])
+    v2 = [1., 2, 3]
+    @test isa(v1 + v2, LazyArray)
+    @test isa(v2 + v1, LazyArray)
+    @test isa(v1 - v2, LazyArray)
+    @test isa(v2 - v1, LazyArray)
+    for i ∈ eachindex(v2)
+        @test (v1 + v2)[i] == (v2 + v1)[i] == r_add_v[i]
+        @test (v1 - v2)[i] == -(v2 - v1)[i] == r_sub_v[i]
+    end
+    @test_throws BoundsError (v1 + v2)[4]
+    v2 = [1., 2, 3, 4]
+    # Test that size of arrays is asserted when not specified inbounds
+    # TODO: Replace these errors with SizeMismatch
+    @test_throws DimensionMismatch v1 + v2
+end
+
+
+@testset "LazyFunctionArray" begin
+    @test LazyFunctionArray(i->i^2, (3,)) == [1,4,9]
+    @test LazyFunctionArray((i,j)->i*j, (3,2)) == [
+        1 2;
+        2 4;
+        3 6;
+    ]
+
+    @test size(LazyFunctionArray(i->i^2, (3,))) == (3,)
+    @test size(LazyFunctionArray((i,j)->i*j, (3,2))) == (3,2)
+
+    @inferred LazyFunctionArray(i->i^2, (3,))[2]
+
+    @test_throws BoundsError LazyFunctionArray(i->i^2, (3,))[4]
+    @test_throws BoundsError LazyFunctionArray((i,j)->i*j, (3,2))[4,2]
+    @test_throws BoundsError LazyFunctionArray((i,j)->i*j, (3,2))[2,3]
+
+end