Merge pull request #2695 from SciML/ChrisRackauckas-patch-2

Don't double recurse init with default algorithm

Author: ChrisRackauckas

lib/OrdinaryDiffEqDefault/src/default_alg.jl

@@ -40,12 +40,12 @@ function isdefaultalg(alg::CompositeAlgorithm{
 end
 
 function DiffEqBase.__init(prob::ODEProblem, ::Nothing, args...; kwargs...)
-    DiffEqBase.init(
+    DiffEqBase.__init(
         prob, DefaultODEAlgorithm(autodiff = AutoFiniteDiff()),
         args...; wrap = Val(false), kwargs...)
 end
 function DiffEqBase.__solve(prob::ODEProblem, ::Nothing, args...; kwargs...)
-    DiffEqBase.solve(
+    DiffEqBase.__solve(
         prob, DefaultODEAlgorithm(autodiff = AutoFiniteDiff()),
         args...; wrap = Val(false), kwargs...)
 end

lib/OrdinaryDiffEqDefault/test/default_solver_tests.jl

@@ -124,3 +124,12 @@ schrod_eq(state, time, s) = -im * time * H(s) * state
 prob_complex = ODEProblem(schrod_eq, complex([1, -1] / sqrt(2)), (0, 1), 100)
 complex_sol = solve(prob_complex)
 @test complex_sol.retcode == ReturnCode.Success
+
+# Make sure callback doesn't recurse init, which would cause iniitalize to be hit twice
+counter = Ref{Int}(0)
+cb = DiscreteCallback((u,t,integ)->false, (integ)->nothing;
+    initialize = (c,u,t,integ)->counter[]+=1)
+
+prob = ODEProblem((u,p,t)->[0.0], [0.0], (0.0,1.0))
+sol = solve(prob, callback=cb)
+@test counter[] == 1