From b656dd15d192cd94e95f21a509cd694929034da7 Mon Sep 17 00:00:00 2001
From: Blanca Luo <ql101@wellesley.edu>
Date: Mon, 11 Nov 2024 14:11:39 -0500
Subject: [PATCH] Apply hash consing to `Add`

---
 src/types.jl         |  4 +++-
 test/hash_consing.jl | 16 +++++++++++++++-
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/src/types.jl b/src/types.jl
index 81220ebd..f2b0cfa9 100644
--- a/src/types.jl
+++ b/src/types.jl
@@ -98,6 +98,7 @@ function ConstructionBase.setproperties(obj::BasicSymbolic{T}, patch::NamedTuple
     @compactified obj::BasicSymbolic begin
         Sym => Sym{T}(nt_new.name; nt_new...)
         Term => Term{T}(nt_new.f, nt_new.arguments; nt_new...)
+        Add => Add(T, nt_new.coeff, nt_new.dict; nt_new...)
         _ => Unityper.rt_constructor(obj){T}(;nt_new...)
     end
 end
@@ -418,7 +419,8 @@ function Add(::Type{T}, coeff, dict; metadata=NO_METADATA, kw...) where T
         end
     end
 
-    Add{T}(; coeff, dict, hash=Ref(UInt(0)), metadata, arguments=[], issorted=RefValue(false), kw...)
+    s = Add{T}(; coeff, dict, hash=Ref(UInt(0)), metadata, arguments=[], issorted=RefValue(false), kw...)
+    BasicSymbolic(s)
 end
 
 function Mul(T, a, b; metadata=NO_METADATA, kw...)
diff --git a/test/hash_consing.jl b/test/hash_consing.jl
index 82385736..ccb8c60f 100644
--- a/test/hash_consing.jl
+++ b/test/hash_consing.jl
@@ -1,5 +1,5 @@
 using SymbolicUtils, Test
-using SymbolicUtils: Term
+using SymbolicUtils: Term, Add
 
 struct Ctx1 end
 struct Ctx2 end
@@ -40,3 +40,17 @@ end
     tm1 = setmetadata(t1, Ctx1, "meta_1")
     @test t1 !== tm1
 end
+
+# @testset "Add" begin
+#     d1 = a + b
+#     d2 = b + a
+#     @test d1 === d2
+#     d3 = b - 2 + a
+#     d4 = a + b  - 2
+#     @test d3 === d4
+#     d5 = Add({Int},a,b)
+#     @test d5 !== d1
+
+#     dm1 = setmetadata(d1,Ctx1,"meta_1")
+#     @test d1 !== dm1
+# end