Merge pull request #1220 from ChrisRackauckas-Claude/add-subarray-support-test

Add downstream test for SubArray support

Author: ChrisRackauckas

test/downstream/subarray_support.jl

@@ -0,0 +1,89 @@
+using OrdinaryDiffEq
+using Test
+
+# Test for SubArray support with ODEProblem
+# Regression test for https://github.com/SciML/OrdinaryDiffEq.jl/issues/2900
+# Fixed in https://github.com/SciML/DiffEqBase.jl/pull/1219
+
+@testset "SubArray as initial conditions" begin
+    # Test 1: Simple ODE with SubArray initial conditions
+    @testset "Basic ODE with SubArray" begin
+        f(du, u, p, t) = du .= u
+        u0_full = ones(10)
+        u0 = @view u0_full[1:5]
+
+        # This should not throw NoFunctionWrapperFoundError
+        prob = ODEProblem(f, u0, (0.0, 1.0))
+        sol = solve(prob, Tsit5())
+
+        @test sol.retcode == ReturnCode.Success
+        @test length(sol[end]) == 5
+    end
+
+    # Test 2: Simple pendulum with SubArray initial conditions
+    @testset "Simple pendulum with SubArray" begin
+        g = 9.81
+        L = 1.00
+
+        # Initial Conditions as SubArray
+        u₀ = @view [0, π / 60][:]  # Initial speed and initial angle
+        tspan = (0.0, 6.3)
+
+        # Define the pendulum problem
+        function simplependulum(du, u, p, t)
+            θ = u[1]
+            dθ = u[2]
+            du[1] = dθ
+            du[2] = -(g / L) * θ
+        end
+
+        # This should not throw NoFunctionWrapperFoundError
+        prob = ODEProblem(simplependulum, u₀, tspan)
+        integrator = init(prob, Tsit5(); reltol = 1e-6)
+
+        @test integrator !== nothing
+
+        # Solve and verify the solution
+        sol = solve(prob, Tsit5(); reltol = 1e-6)
+        @test sol.retcode == ReturnCode.Success
+        @test length(sol[end]) == 2
+    end
+
+    # Test 3: Various SubArray slicing patterns
+    @testset "Different SubArray patterns" begin
+        f(du, u, p, t) = du .= 2u
+
+        # Test different ways to create SubArrays
+        @testset "range slice" begin
+            arr = [1.0, 2.0, 3.0]
+            u0 = @view arr[1:2]
+            prob = ODEProblem(f, u0, (0.0, 1.0))
+            sol = solve(prob, Tsit5())
+            @test sol.retcode == ReturnCode.Success
+        end
+
+        @testset "colon slice" begin
+            arr = [1.0, 2.0, 3.0]
+            u0 = @view arr[:]
+            prob = ODEProblem(f, u0, (0.0, 1.0))
+            sol = solve(prob, Tsit5())
+            @test sol.retcode == ReturnCode.Success
+        end
+
+        @testset "offset range" begin
+            arr = [1.0, 2.0, 3.0]
+            u0 = @view arr[2:3]
+            prob = ODEProblem(f, u0, (0.0, 1.0))
+            sol = solve(prob, Tsit5())
+            @test sol.retcode == ReturnCode.Success
+        end
+
+        @testset "view of constructed array" begin
+            arr = ones(5)
+            u0 = @view arr[1:3]
+            prob = ODEProblem(f, u0, (0.0, 1.0))
+            sol = solve(prob, Tsit5())
+            @test sol.retcode == ReturnCode.Success
+        end
+    end
+end

test/runtests.jl

@@ -59,6 +59,7 @@ end
         @time @safetestset "Callback Merging Tests" include("downstream/callback_merging.jl")
         @time @safetestset "LabelledArrays Tests" include("downstream/labelledarrays.jl")
         @time @safetestset "GTPSA Tests" include("downstream/gtpsa.jl")
+        @time @safetestset "SubArray Support" include("downstream/subarray_support.jl")
     end
 
     if !is_APPVEYOR && GROUP == "Static"