make initialization_data for IMplicitDIscreteFunction, fix bad initialization test

Author: vyudu

src/systems/discrete_system/implicit_discrete_system.jl

@@ -334,8 +334,10 @@ function SciMLBase.ImplicitDiscreteProblem(
 
     u0map = to_varmap(u0map, dvs)
     u0map = shift_u0map_forward(sys, u0map, defaults(sys))
+    @show u0map
     f, u0, p = process_SciMLProblem(
         ImplicitDiscreteFunction, sys, u0map, parammap; eval_expression, eval_module, kwargs...)
+    @show u0
 
     kwargs = filter_kwargs(kwargs)
     ImplicitDiscreteProblem(f, u0, tspan, p; kwargs...)
@@ -388,7 +390,8 @@ function SciMLBase.ImplicitDiscreteFunction{iip, specialize}(
     ImplicitDiscreteFunction{iip, specialize}(f;
         sys = sys,
         observed = observedfun,
-        analytic = analytic)
+        analytic = analytic,
+        kwargs...)
 end
 
 """

test/implicit_discrete_system.jl

@@ -53,7 +53,7 @@ end
     # Initialization is satisfied.
     prob = ImplicitDiscreteProblem(
         sys, [x(k - 1) => 0.3, x(k - 2) => 0.4], (0, 10), guesses = [y => 1])
-    @test (prob.u0[1] + prob.u0[2])^2 + prob.u0[3]^2 ≈ 1
+    @test length(equations(prob.f.initialization_data.initializeprob.f.sys)) == 1
 end
 
 @testset "Handle observables in function codegen" begin