add test

Author: oscardssmith

test/interface/ode_initdt_tests.jl

@@ -64,3 +64,9 @@ sol = solve(prob, Rodas5())
 # test that dtmin is set based on timespan
 prob = ODEProblem((u, p, t) -> 1e20 * sin(1e20 * t), 0.1, (0, 1e-19))
 @test solve(prob, Tsit5()).retcode == ReturnCode.Success
+
+#test that we are robust to u0=0, t0!=0
+integ = init(ODEProblem(((u,p,t)->u), 0f0, (20f0, 0f0)), Tsit5())
+@test abs(integ.dt) > eps(integ.t)
+integ = init(ODEProblem(((du,u,p,t)->du.=u), [0f0], (20f0, 0f0)), Tsit5())
+@test abs(integ.dt) > eps(integ.t)