Add special case for frozen tables

Sources will now check if frozen tables are equal before updating
dependencies.

src/source.luau

@@ -15,7 +15,7 @@ local function source<T>(value: T): Source<T>
         if select("#", ...) == 0 then return get_value() end
 
         local v = ... :: T
-        if node.cache == v and type(v) ~= "table" then return v end
+        if node.cache == v and (type(v) ~= "table" or table.isfrozen(v)) then return v end
 
         set(node, v)
         return v

test/tests.luau

@@ -192,6 +192,27 @@ TEST("source()", function()
         state(state())
         CHECK(updates == 1)
     end
+
+    do CASE "does not update if same value is frozen table"
+        local a = table.freeze {}
+        local b = table.freeze {}
+
+        local state = source(a)
+
+        local updates = -1
+        watch(function()
+            state()
+            updates += 1
+        end)
+
+        CHECK(updates == 0)
+        state(a)
+        CHECK(updates == 0)
+        state(b)
+        CHECK(updates == 1)
+        state(b)
+        CHECK(updates == 1)
+    end
 end)
 
 TEST("derive()", function()

todo.md

@@ -14,5 +14,6 @@
   - [ ] untrack
   - [ ] batch
   - [ ] async/resource/loading/suspense
+  - [ ] stores
 - define order with nested properties
   - review alternative to nested properties, merge function