Add a non-deprecating code path

Author: avik-pal

Project.toml

@@ -1,6 +1,6 @@
 name = "BoundaryValueDiffEq"
 uuid = "764a87c0-6b3e-53db-9096-fe964310641d"
-version = "6.0.0"
+version = "5.4.0"
 
 [deps]
 ADTypes = "47edcb42-4c32-4615-8424-f2b9edc5f35b"

src/algorithms.jl

@@ -15,7 +15,7 @@ Single shooting method, reduces BVP to an initial value problem and solves the I
 ## Keyword Arguments
 
   - `nlsolve`: Internal Nonlinear solver. Any solver which conforms to the SciML
-    `NonlinearProblem` interface can be used.Note that any autodiff argument for the solver
+    `NonlinearProblem` interface can be used. Note that any autodiff argument for the solver
     will be ignored and a custom jacobian algorithm will be used.
   - `jac_alg`: Jacobian Algorithm used for the nonlinear solver. Defaults to
     `BVPJacobianAlgorithm()`, which automatically decides the best algorithm to use based
@@ -39,12 +39,25 @@ function concretize_jacobian_algorithm(alg::Shooting, prob)
     return Shooting(alg.ode_alg, alg.nlsolve, BVPJacobianAlgorithm(diffmode))
 end
 
-function Shooting(ode_alg, nlsolve; jac_alg = BVPJacobianAlgorithm())
+function Shooting(ode_alg; nlsolve = NewtonRaphson(), jac_alg = nothing)
+    jac_alg === nothing && (jac_alg = __propagate_nlsolve_ad_to_jac_alg(nlsolve))
     return Shooting(ode_alg, nlsolve, jac_alg)
 end
 
-function Shooting(ode_alg; nlsolve = NewtonRaphson(), jac_alg = BVPJacobianAlgorithm())
-    return Shooting(ode_alg, nlsolve, jac_alg)
+Shooting(ode_alg, nlsolve; jac_alg = nothing) = Shooting(ode_alg; nlsolve, jac_alg)
+
+# This is a deprecation path. We forward the `ad` from nonlinear solver to `jac_alg`.
+# We will drop this function in
+function __propagate_nlsolve_ad_to_jac_alg(nlsolve::N) where {N}
+    # Defaults so no depwarn
+    nlsolve === nothing && return BVPJacobianAlgorithm()
+    ad = hasfield(N, :ad) ? nlsolve.ad : nothing
+    ad === nothing && return BVPJacobianAlgorithm()
+
+    Base.depwarn("Setting autodiff to the nonlinear solver in Shooting has been deprecated \
+                  and will have no effect from the next major release. Update to use \
+                  `BVPJacobianAlgorithm` directly", :Shooting)
+    return BVPJacobianAlgorithm(ad)
 end
 
 """

test/shooting/shooting_tests.jl

@@ -161,3 +161,12 @@ end
     bc_flow!(resid, sol_msshooting, p, sol_msshooting.t)
     @test norm(resid, Inf) < 1e-6
 end
+
+@testset "Testing Deprecations" begin
+    @test_deprecated Shooting(Tsit5();
+        nlsolve = NewtonRaphson(; autodiff = AutoForwardDiff(chunksize = 2)))
+
+    alg = Shooting(Tsit5();
+        nlsolve = NewtonRaphson(; autodiff = AutoForwardDiff(chunksize = 2)))
+    @test alg.jac_alg.diffmode == AutoForwardDiff(chunksize = 2)
+end