Add cache stripping to solution stripping

lib/OrdinaryDiffEqCore/src/interp_func.jl

@@ -59,3 +59,29 @@ function InterpolationData(id::InterpolationData, f)
         id.differential_vars,
         id.sensitivitymode)
 end
+
+# strip interpolation of function information
+function SciMLBase.strip_interpolation(id::InterpolationData)
+
+    cache = strip_cache(id.cache)
+
+    InterpolationData(nothing, id.timeseries,
+        id.ts,
+        id.ks,
+        id.alg_choice,
+        id.dense,
+        cache,
+        id.differential_vars,
+        id.sensitivitymode)
+end
+
+function strip_cache(cache)
+    if hasfield(typeof(cache), :jac_config) || hasfield(typeof(cache), :grad_config)
+        fieldnums = length(fieldnames(typeof(cache)))
+        noth_list = fill(nothing,fieldnums)
+        cache_type_name = Base.typename(typeof(cache)).wrapper
+        cache_type_name(noth_list...)
+    else
+        cache
+    end
+end

src/OrdinaryDiffEq.jl

@@ -58,7 +58,7 @@ import OrdinaryDiffEqCore: trivial_limiter!, CompositeAlgorithm, alg_order,
                            _change_t_via_interpolation!, ODEIntegrator, _ode_interpolant!,
                            current_interpolant, resize_nlsolver!, _ode_interpolant,
                            handle_tstop!, _postamble!, update_uprev!, resize_J_W!,
-                           DAEAlgorithm, get_fsalfirstlast
+                           DAEAlgorithm, get_fsalfirstlast, strip_cache, strip_interpolation
 
 export CompositeAlgorithm, ShampineCollocationInit, BrownFullBasicInit, NoInit
 AutoSwitch

test/interface/ode_strip_test.jl

@@ -0,0 +1,17 @@
+using OrdinaryDiffEq, Test
+import SciMLBase
+
+function lorenz!(du, u, p, t)
+    du[1] = 10.0 * (u[2] - u[1])
+    du[2] = u[1] * (28.0 - u[3]) - u[2]
+    du[3] = u[1] * u[2] - (8 / 3) * u[3]
+end
+
+u0 = [1.0; 0.0; 0.0]
+tspan = (0.0, 0.5)
+prob = ODEProblem(lorenz!, u0, tspan)
+
+sol = solve(prob, Rosenbrock23())
+
+@test isnothing(SciMLBase.strip_interpolation(sol.interp).f)
+@test isnothing(SciMLBase.strip_interpolation(sol.interp).cache.jac_config)

test/runtests.jl

@@ -56,6 +56,7 @@ end
         @time @safetestset "Inplace Interpolation Tests" include("interface/inplace_interpolation.jl")
         @time @safetestset "Algebraic Interpolation Tests" include("interface/algebraic_interpolation.jl")
         @time @safetestset "Default Solver Tests" include("interface/default_solver_tests.jl")
+        @time @safetestset "Interpolation and Cache Stripping Tests" include("interface/ode_strip_test.jl")
     end
 
     if !is_APPVEYOR && (GROUP == "All" || GROUP == "InterfaceII" || GROUP == "Interface")