From 4062add8edd5c8f7c180fa78a508e7d898cfbb11 Mon Sep 17 00:00:00 2001
From: Sahan Fernando <sahan.h.fernando@gmail.com>
Date: Thu, 3 Dec 2020 22:44:00 +1100
Subject: [PATCH] LibGUI: Optimize GUI::Variant move constructor

---
 Libraries/LibGUI/Variant.cpp | 13 ++++++++++---
 Libraries/LibGUI/Variant.h   |  1 +
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/Libraries/LibGUI/Variant.cpp b/Libraries/LibGUI/Variant.cpp
index 3862870ddd..bd732f0130 100644
--- a/Libraries/LibGUI/Variant.cpp
+++ b/Libraries/LibGUI/Variant.cpp
@@ -26,6 +26,7 @@
 
 #include <AK/FlyString.h>
 #include <AK/JsonValue.h>
+#include <AK/RefPtr.h>
 #include <LibGUI/Variant.h>
 
 namespace GUI {
@@ -255,10 +256,8 @@ Variant& Variant::operator=(Variant&& other)
 {
     if (&other == this)
         return *this;
-    // FIXME: Move, not copy!
     clear();
-    copy_from(other);
-    other.clear();
+    move_from(AK::move(other));
     return *this;
 }
 
@@ -267,6 +266,14 @@ Variant::Variant(const Variant& other)
     copy_from(other);
 }
 
+void Variant::move_from(Variant&& other)
+{
+    m_type = other.m_type;
+    m_value = other.m_value;
+    other.m_type = Type::Invalid;
+    other.m_value.as_string = nullptr;
+}
+
 void Variant::copy_from(const Variant& other)
 {
     ASSERT(!is_valid());
diff --git a/Libraries/LibGUI/Variant.h b/Libraries/LibGUI/Variant.h
index 6e657e75f9..a04f7b2e17 100644
--- a/Libraries/LibGUI/Variant.h
+++ b/Libraries/LibGUI/Variant.h
@@ -250,6 +250,7 @@ public:
 
 private:
     void copy_from(const Variant&);
+    void move_from(Variant&&);
 
     struct RawPoint {
         int x;