Merge pull request #3252 from AayushSabharwal/as/initprob-resid-proto…

…type

fix: recalculate resid_prototype in remake_initialization_data

src/systems/nonlinear/initializesystem.jl

@@ -260,7 +260,16 @@ function SciMLBase.remake_initialization_data(sys::ODESystem, odefn, u0, t0, p,
             newp = remake_buffer(
                 oldinitprob.f.sys, parameter_values(oldinitprob), pidxs, pvals)
         end
-        initprob = remake(oldinitprob; u0 = newu0, p = newp)
+        if oldinitprob.f.resid_prototype === nothing
+            newf = oldinitprob.f
+        else
+            newf = NonlinearFunction{
+                SciMLBase.isinplace(oldinitprob.f), SciMLBase.specialization(oldinitprob.f)}(
+                oldinitprob.f;
+                resid_prototype = calculate_resid_prototype(
+                    length(oldinitprob.f.resid_prototype), newu0, newp))
+        end
+        initprob = remake(oldinitprob; f = newf, u0 = newu0, p = newp)
         return SciMLBase.OverrideInitData(initprob, odefn.update_initializeprob!,
             odefn.initializeprobmap, odefn.initializeprobpmap)
     end

src/systems/nonlinear/nonlinearsystem.jl

@@ -283,6 +283,16 @@ function hessian_sparsity(sys::NonlinearSystem)
          unknowns(sys)) for eq in equations(sys)]
 end
 
+function calculate_resid_prototype(N, u0, p)
+    u0ElType = u0 === nothing ? Float64 : eltype(u0)
+    if SciMLStructures.isscimlstructure(p)
+        u0ElType = promote_type(
+            eltype(SciMLStructures.canonicalize(SciMLStructures.Tunable(), p)[1]),
+            u0ElType)
+    end
+    return zeros(u0ElType, N)
+end
+
 """
 ```julia
 SciMLBase.NonlinearFunction{iip}(sys::NonlinearSystem, dvs = unknowns(sys),
@@ -337,13 +347,7 @@ function SciMLBase.NonlinearFunction{iip}(sys::NonlinearSystem, dvs = unknowns(s
     if length(dvs) == length(equations(sys))
         resid_prototype = nothing
     else
-        u0ElType = u0 === nothing ? Float64 : eltype(u0)
-        if SciMLStructures.isscimlstructure(p)
-            u0ElType = promote_type(
-                eltype(SciMLStructures.canonicalize(SciMLStructures.Tunable(), p)[1]),
-                u0ElType)
-        end
-        resid_prototype = zeros(u0ElType, length(equations(sys)))
+        resid_prototype = calculate_resid_prototype(length(equations(sys)), u0, p)
     end
 
     NonlinearFunction{iip}(f,

test/initializationsystem.jl

@@ -1032,3 +1032,20 @@ end
     @test prob3.f.initialization_data !== nothing
     @test init(prob3)[x] ≈ 0.5
 end
+
+@testset "Issue#3246: type promotion with parameter dependent initialization_eqs" begin
+    @variables x(t)=1 y(t)=1
+    @parameters a = 1
+    @named sys = ODESystem([D(x) ~ 0, D(y) ~ x + a], t; initialization_eqs = [y ~ a])
+
+    ssys = structural_simplify(sys)
+    prob = ODEProblem(ssys, [], (0, 1), [])
+
+    @test SciMLBase.successful_retcode(solve(prob))
+
+    seta = setsym_oop(prob, [a])
+    (newu0, newp) = seta(prob, ForwardDiff.Dual{ForwardDiff.Tag{:tag, Float64}}.([1.0], 1))
+    newprob = remake(prob, u0 = newu0, p = newp)
+
+    @test SciMLBase.successful_retcode(solve(newprob))
+end