From 1c8978f8b8675bb373e5194e69ec78926666fc31 Mon Sep 17 00:00:00 2001
From: Aayush Sabharwal <aayush.sabharwal@juliahub.com>
Date: Thu, 25 Jan 2024 18:01:53 +0530
Subject: [PATCH] refactor: update for MTKv9

---
 Project.toml                               |  2 +-
 lib/OptimizationMOI/Project.toml           |  2 +-
 lib/OptimizationMOI/src/OptimizationMOI.jl |  8 ++---
 src/cache.jl                               | 37 ----------------------
 4 files changed, 6 insertions(+), 43 deletions(-)

diff --git a/Project.toml b/Project.toml
index ed6e47638..3c35803e0 100644
--- a/Project.toml
+++ b/Project.toml
@@ -51,7 +51,7 @@ ForwardDiff = "0.10.26"
 LinearAlgebra = "1.10"
 Logging = "1.10"
 LoggingExtras = "0.4, 1"
-ModelingToolkit = "8.74"
+ModelingToolkit = "8.74, 9"
 Pkg = "1"
 Printf = "1.10"
 ProgressLogging = "0.1"
diff --git a/lib/OptimizationMOI/Project.toml b/lib/OptimizationMOI/Project.toml
index 47a4585d3..aa27ad0af 100644
--- a/lib/OptimizationMOI/Project.toml
+++ b/lib/OptimizationMOI/Project.toml
@@ -17,7 +17,7 @@ Symbolics = "0c5d862f-8b57-4792-8d23-62f2024744c7"
 Ipopt_jll = "=300.1400.400"
 Juniper = "0.9"
 MathOptInterface = "1"
-ModelingToolkit = "8.74"
+ModelingToolkit = "9"
 Optimization = "3.21"
 Reexport = "1.2"
 SymbolicIndexingInterface = "0.3"
diff --git a/lib/OptimizationMOI/src/OptimizationMOI.jl b/lib/OptimizationMOI/src/OptimizationMOI.jl
index 6a30b7860..72f2cde17 100644
--- a/lib/OptimizationMOI/src/OptimizationMOI.jl
+++ b/lib/OptimizationMOI/src/OptimizationMOI.jl
@@ -6,7 +6,7 @@ using MathOptInterface
 using Optimization.SciMLBase
 using SymbolicIndexingInterface
 using SparseArrays
-import ModelingToolkit: parameters, states, varmap_to_vars, mergedefaults, toexpr
+import ModelingToolkit: parameters, unknowns, varmap_to_vars, mergedefaults, toexpr
 import ModelingToolkit
 const MTK = ModelingToolkit
 using Symbolics
@@ -182,12 +182,12 @@ end
 """
     convert_to_expr(eq, sys; expand_expr = false, pairs_arr = expr_map(sys))
 
-Converts the given symbolic expression to a Julia `Expr` and replaces all symbols, i.e. states and
+Converts the given symbolic expression to a Julia `Expr` and replaces all symbols, i.e. unknowns and
 parameters with `x[i]` and `p[i]`.
 
 # Arguments:
 - `eq`: Expression to convert
-- `sys`: Reference to the system holding the parameters and states
+- `sys`: Reference to the system holding the parameters and unknowns
 - `expand_expr=false`: If `true` the symbolic expression is expanded first.
 """
 function convert_to_expr(eq, expr_map; expand_expr = false)
@@ -206,7 +206,7 @@ function convert_to_expr(eq, expr_map; expand_expr = false)
 end
 
 function get_expr_map(sys)
-    dvs = ModelingToolkit.states(sys)
+    dvs = ModelingToolkit.unknowns(sys)
     ps = ModelingToolkit.parameters(sys)
     return vcat([ModelingToolkit.toexpr(_s) => Expr(:ref, :x, i)
                  for (i, _s) in enumerate(dvs)],
diff --git a/src/cache.jl b/src/cache.jl
index a7a856ba6..a638fac86 100644
--- a/src/cache.jl
+++ b/src/cache.jl
@@ -1,40 +1,3 @@
-
-function Base.getproperty(cache::SciMLBase.AbstractOptimizationCache, x::Symbol)
-    if x in (:u0, :p)
-        return getfield(cache.reinit_cache, x)
-    end
-    return getfield(cache, x)
-end
-
-SciMLBase.has_reinit(cache::SciMLBase.AbstractOptimizationCache) = true
-function SciMLBase.reinit!(cache::SciMLBase.AbstractOptimizationCache; p = missing,
-        u0 = missing)
-    if p === missing && u0 === missing
-        p, u0 = cache.p, cache.u0
-    else # at least one of them has a value
-        if p === missing
-            p = cache.p
-        end
-        if u0 === missing
-            u0 = cache.u0
-        end
-        if (eltype(p) <: Pair && !isempty(p)) || (eltype(u0) <: Pair && !isempty(u0)) # one is a non-empty symbolic map
-            hasproperty(cache.f, :sys) && hasfield(typeof(cache.f.sys), :ps) ||
-                throw(ArgumentError("This cache does not support symbolic maps with `remake`, i.e. it does not have a symbolic origin." *
-                                    " Please use `remake` with the `p` keyword argument as a vector of values, paying attention to parameter order."))
-            hasproperty(cache.f, :sys) && hasfield(typeof(cache.f.sys), :states) ||
-                throw(ArgumentError("This cache does not support symbolic maps with `remake`, i.e. it does not have a symbolic origin." *
-                                    " Please use `remake` with the `u0` keyword argument as a vector of values, paying attention to state order."))
-            p, u0 = SciMLBase.process_p_u0_symbolic(cache, p, u0)
-        end
-    end
-
-    cache.reinit_cache.p = p
-    cache.reinit_cache.u0 = u0
-
-    return cache
-end
-
 struct OptimizationCache{F, RC, LB, UB, LC, UC, S, O, D, P, C} <:
        SciMLBase.AbstractOptimizationCache
     f::F