add tests for large sparse jacobians

Author: jClugstor

test/interface/autosparse_detection_tests.jl

@@ -1,6 +1,6 @@
-using Test, OrdinaryDiffEq, LinearSolve, ADTypes, ForwardDiff, SparseConnectivityTracer, SparseMatrixColorings
+using Test, OrdinaryDiffEq, LinearSolve, ADTypes, ForwardDiff, SparseConnectivityTracer,
+      SparseMatrixColorings
 import ODEProblemLibrary: prob_ode_2Dlinear
-                    
 
 ad = AutoSparse(AutoForwardDiff(), sparsity_detector = TracerSparsityDetector(),
     coloring_algorithm = GreedyColoringAlgorithm())
@@ -9,5 +9,12 @@ prob = prob_ode_2Dlinear
 
 @test_nowarn solve(prob, Rodas5(autodiff = ad))
 
-@test_nowarn solve(prob, Rodas5(autodiff = ad, linsolve = LinearSolve.KrylovJL()))
+@test_nowarn solve(prob, Rodas5(autodiff = ad, linsolve = LinearSolve.KrylovJL_GMRES()))
 
+# Test that no dense matrices are made sparse
+diag_prob = ODEProblem((du, u, p, t) -> 1.0 .* u, rand(Int(1e7)), (0, 100.0))
+
+@test_nowarn solve(diag_prob, Rodas5P(autodiff = ad))
+
+@test_nowarn solve(
+    diag_prob, Rodas5P(autodiff = ad, linsolve = LinearSolve.KrylovJL_GMRES()))