Restore isdiscretecache public API

Co-Authored-By: Chris Rackauckas <accounts@chrisrackauckas.com>

Author: ChrisRackauckas

docs/src/devtools/internals/public_api.md

@@ -132,6 +132,7 @@ OrdinaryDiffEqCore.has_stiff_interpolation
 OrdinaryDiffEqCore.allows_null_u0
 OrdinaryDiffEqCore.isaposteriori
 OrdinaryDiffEqCore.isdiscretealg
+OrdinaryDiffEqCore.isdiscretecache
 OrdinaryDiffEqCore.isdp8
 OrdinaryDiffEqCore.isesdirk
 OrdinaryDiffEqCore.isfirk

lib/OrdinaryDiffEqCore/src/OrdinaryDiffEqCore.jl

@@ -435,7 +435,7 @@ include("precompilation_setup.jl")
             :get_gamma, :get_new_W_γdt_cutoff, :get_qmax, :get_qmax_first_step, :get_qmin, :get_qsteady_max,
             :get_qsteady_min, :get_W, :GLM, :hermite_interpolant, :IController,
             :ImplicitSecondOrderAlgorithm, :increment_accept!, :increment_nf!, :increment_reject!, :InterpolationData, :isautoswitch,
-            :is_composite_algorithm, :isdefaultalg, :isdtchangeable, :isfirstcall,
+            :is_composite_algorithm, :isdefaultalg, :isdiscretecache, :isdtchangeable, :isfirstcall,
             :isfirststage, :isfsal, :isimplicit, :isJcurrent, :is_mass_matrix_alg, :ismultistep,
             :issplit, :isthreaded, :isWmethod, :MethodType, :NewtonAlgorithm, :nlsolve_f,
             :NLStatus, :NORDSIECK_MULTISTEP, :_ode_addsteps!, :ode_addsteps!, :ODEIntegrator, :_ode_interpolant,

lib/OrdinaryDiffEqCore/test/qa/qa.jl

@@ -4,6 +4,10 @@ using SciMLTesting, OrdinaryDiffEqCore, Test
 # ExplicitImports cannot statically analyze; allow it to be unanalyzable.
 const UNANALYZABLE = (OrdinaryDiffEqCore.Predictor,)
 
+@static if VERSION >= v"1.11.0-DEV.469"
+    @test Base.ispublic(OrdinaryDiffEqCore, :isdiscretecache)
+end
+
 run_qa(
     OrdinaryDiffEqCore;
     aqua_kwargs = (; piracies = false, unbound_args = false),