Implement Eq for Gd<T>

Author: Bromeon

godot-core/src/obj/gd.rs

@@ -626,6 +626,19 @@ impl<T: GodotClass> ToVariant for Gd<T> {
     }
 }
 
+impl<T: GodotClass> PartialEq for Gd<T> {
+    /// ⚠️ Returns whether two `Gd` pointers point to the same object.
+    ///
+    /// # Panics
+    /// When `self` or `other` is dead.
+    fn eq(&self, other: &Self) -> bool {
+        // Panics when one is dead
+        self.instance_id() == other.instance_id()
+    }
+}
+
+impl<T: GodotClass> Eq for Gd<T> {}
+
 impl<T> Display for Gd<T>
 where
     T: GodotClass<Declarer = dom::EngineDomain>,

itest/rust/src/object_test.rs

@@ -161,6 +161,35 @@ fn object_from_instance_id_unrelated_type() {
     node.free();
 }
 
+#[itest]
+fn object_user_eq() {
+    let value: i16 = 17943;
+    let a = ObjPayload { value };
+    let b = ObjPayload { value };
+
+    let a1 = Gd::new(a);
+    let a2 = a1.share();
+    let b1 = Gd::new(b);
+
+    assert_eq!(a1, a2);
+    assert_ne!(a1, b1);
+    assert_ne!(a2, b1);
+}
+
+#[itest]
+fn object_engine_eq() {
+    let a1 = Node3D::new_alloc();
+    let a2 = a1.share();
+    let b1 = Node3D::new_alloc();
+
+    assert_eq!(a1, a2);
+    assert_ne!(a1, b1);
+    assert_ne!(a2, b1);
+
+    a1.free();
+    b1.free();
+}
+
 #[itest]
 fn object_user_convert_variant() {
     let value: i16 = 17943;