Fix default algorithm adjoint

.github/workflows/CI.yml

@@ -24,6 +24,7 @@ jobs:
           - Core5
           - Core6
           - Core7
+          - DiffEq
           - SDE1
           - SDE2
           - SDE3

src/adjoint_common.jl

@@ -104,7 +104,7 @@ function adjointdiffcache(g::G, sensealg, discrete, sol, dgdu::DG1, dgdp::DG2, f
     if !needs_jac && !issemiexplicitdae && !(autojacvec isa Bool)
         J = nothing
     else
-        if SciMLBase.forwarddiffs_model_time(alg)
+        if alg === nothing || SciMLBase.forwarddiffs_model_time(alg)
             # 1 chunk is fine because it's only t
             J = dualcache(similar(u0, numindvar, numindvar),
                 ForwardDiff.pickchunksize(length(u0)))

test/diffeq/Project.toml

@@ -0,0 +1,5 @@
+[deps]
+DifferentialEquations = "0c46a032-eb83-5123-abaf-570d42b7fbaa"
+
+[compat]
+DifferentialEquations = "7"

test/diffeq/default_alg_diff.jl

@@ -0,0 +1,21 @@
+using ComponentArrays, DifferentialEquations, Lux, Random, SciMLSensitivity, Zygote
+
+function f(du, u, p, t)
+    du .= first(nn(u, p, st))
+    nothing
+end
+
+nn = Dense(8, 8, tanh)
+ps, st = Lux.setup(Random.default_rng(), nn)
+ps = ComponentArray(ps)
+
+r = rand(Float32, 8, 64)
+
+function f2(x)
+    prob = ODEProblem(f, r, (0.0f0, 1.0f0), x)
+    sol = solve(prob; sensealg = InterpolatingAdjoint(; autodiff = true, autojacvec = true))
+    sum(last(sol.u))
+end
+
+f2(ps)
+Zygote.gradient(f2, ps)

test/runtests.jl

@@ -9,6 +9,12 @@ function activate_gpu_env()
     Pkg.instantiate()
 end
 
+function activate_diffeq_env()
+    Pkg.activate("diffeq")
+    Pkg.develop(PackageSpec(path = dirname(@__DIR__)))
+    Pkg.instantiate()
+end
+
 @time @testset "SciMLSensitivity" begin
     if GROUP == "All" || GROUP == "Core1" || GROUP == "Downstream"
         @testset "Core1" begin
@@ -144,6 +150,13 @@ end
         end
     end
 
+    if GROUP == "DiffEq"
+        @testset "DiffEq" begin
+            activate_gpu_env()
+            @time @safetestset "Default DiffEq Alg" include("diffeq/default_alg_diff.jl")
+        end
+    end
+
     if GROUP == "GPU"
         @testset "GPU" begin
             activate_gpu_env()