feat: forwarddiff support for sundials

Author: avik-pal

Project.toml

@@ -44,6 +44,7 @@ NLSolvers = "337daf1e-9722-11e9-073e-8b9effe078ba"
 NLsolve = "2774e3e8-f4cf-5e23-947b-6d7e65073b56"
 SIAMFANLEquations = "084e46ad-d928-497d-ad5e-07fa361a48c4"
 SpeedMapping = "f1835b91-879b-4a3f-a438-e4baacf14412"
+Sundials = "c3572dad-4567-51f8-b174-8c6c989267f4"
 
 [extensions]
 NonlinearSolveBandedMatricesExt = "BandedMatrices"
@@ -55,6 +56,7 @@ NonlinearSolveNLSolversExt = "NLSolvers"
 NonlinearSolveNLsolveExt = ["NLsolve", "LineSearches"]
 NonlinearSolveSIAMFANLEquationsExt = "SIAMFANLEquations"
 NonlinearSolveSpeedMappingExt = "SpeedMapping"
+NonlinearSolveSundialsExt = "Sundials"
 
 [compat]
 ADTypes = "1.9"

ext/NonlinearSolveSundialsExt.jl

@@ -0,0 +1,16 @@
+module NonlinearSolveSundialsExt
+
+using NonlinearSolveBase: NonlinearSolveBase, nonlinearsolve_forwarddiff_solve,
+                          nonlinearsolve_dual_solution
+using NonlinearSolve: DualNonlinearProblem
+using SciMLBase: SciMLBase
+using Sundials: KINSOL
+
+function SciMLBase.__solve(prob::DualNonlinearProblem, alg::KINSOL, args...; kwargs...)
+    sol, partials = nonlinearsolve_forwarddiff_solve(prob, alg, args...; kwargs...)
+    dual_soln = nonlinearsolve_dual_solution(sol.u, partials, prob.p)
+    return SciMLBase.build_solution(
+        prob, alg, dual_soln, sol.resid; sol.retcode, sol.stats, sol.original)
+end
+
+end