roblox_emulator: implement IsAncestorOf & IsDescendantOf

lib/roblox_emulator/src/runner/instance/instance.rs

@@ -250,6 +250,18 @@ impl mlua::UserData for Instance{
 				Ok(children)
 			})
 		);
+		methods.add_method("IsAncestorOf",|lua,this,descendant:Instance|
+			dom_mut(lua,|dom|{
+				let instance=descendant.get(dom)?;
+				Ok(std::iter::successors(Some(instance),|inst|dom.get_by_ref(inst.parent())).any(|inst|inst.referent()==this.referent))
+			})
+		);
+		methods.add_method("IsDescendantOf",|lua,this,ancestor:Instance|
+			dom_mut(lua,|dom|{
+				let instance=this.get(dom)?;
+				Ok(std::iter::successors(Some(instance),|inst|dom.get_by_ref(inst.parent())).any(|inst|inst.referent()==ancestor.referent))
+			})
+		);
 		fn is_a(lua:&mlua::Lua,this:&Instance,classname:mlua::String)->mlua::Result<bool>{
 			dom_mut(lua,|dom|{
 				let instance=this.get(dom)?;