From d00a6ca11f5c4fe23c87141e2de32db7a72002d1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?kleines=20Filmr=C3=B6llchen?= <filmroellchen@serenityos.org>
Date: Tue, 7 Feb 2023 21:10:15 +0100
Subject: [PATCH] AK+LibWeb: Implement Variant equality operator

And make use of it for CSS StyleValues.
---
 AK/Variant.h                                 |  9 ++++++
 Userland/Libraries/LibWeb/CSS/StyleValue.cpp | 34 ++------------------
 2 files changed, 12 insertions(+), 31 deletions(-)

diff --git a/AK/Variant.h b/AK/Variant.h
index ed477b7bd4..46ed67c48b 100644
--- a/AK/Variant.h
+++ b/AK/Variant.h
@@ -418,6 +418,15 @@ public:
         return index_of<T>() == m_index;
     }
 
+    bool operator==(Variant const& other) const
+    {
+        return this->visit([&]<typename T>(T const& self) {
+            if (auto const* p = other.get_pointer<T>())
+                return static_cast<T const&>(self) == static_cast<T const&>(*p);
+            return false;
+        });
+    }
+
     template<typename... Fs>
     ALWAYS_INLINE decltype(auto) visit(Fs&&... functions)
     {
diff --git a/Userland/Libraries/LibWeb/CSS/StyleValue.cpp b/Userland/Libraries/LibWeb/CSS/StyleValue.cpp
index e158482b6b..ca42cb4d2b 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleValue.cpp
+++ b/Userland/Libraries/LibWeb/CSS/StyleValue.cpp
@@ -1331,25 +1331,6 @@ static bool operator==(Filter::HueRotate const& a, Filter::HueRotate const& b)
     return a.angle == b.angle;
 }
 
-static bool variant_equals(auto const& a, auto const& b)
-{
-    return a.visit([&](auto const& held_value) {
-        using HeldType = AK::Detail::Decay<decltype(held_value)>;
-        bool other_holds_same_type = b.template has<HeldType>();
-        return other_holds_same_type && held_value == b.template get<HeldType>();
-    });
-}
-
-static bool operator==(Filter::HueRotate::AngleOrZero const& a, Filter::HueRotate::AngleOrZero const& b)
-{
-    return variant_equals(a, b);
-}
-
-static bool operator==(FilterFunction const& a, FilterFunction const& b)
-{
-    return variant_equals(a, b);
-}
-
 bool FilterValueListStyleValue::equals(StyleValue const& other) const
 {
     if (type() != other.type())
@@ -1867,15 +1848,6 @@ ErrorOr<String> LinearGradientStyleValue::to_string() const
     return builder.to_string();
 }
 
-static bool operator==(LinearGradientStyleValue::GradientDirection const& a, LinearGradientStyleValue::GradientDirection const& b)
-{
-    if (a.has<SideOrCorner>() && b.has<SideOrCorner>())
-        return a.get<SideOrCorner>() == b.get<SideOrCorner>();
-    if (a.has<Angle>() && b.has<Angle>())
-        return a.get<Angle>() == b.get<Angle>();
-    return false;
-}
-
 static bool operator==(EdgeRect const& a, EdgeRect const& b)
 {
     return a.top_edge == b.top_edge && a.right_edge == b.right_edge && a.bottom_edge == b.bottom_edge && a.left_edge == b.left_edge;
@@ -2043,8 +2015,8 @@ bool PositionValue::operator==(PositionValue const& other) const
     return (
         x_relative_to == other.x_relative_to
         && y_relative_to == other.y_relative_to
-        && variant_equals(horizontal_position, other.horizontal_position)
-        && variant_equals(vertical_position, other.vertical_position));
+        && horizontal_position == other.horizontal_position
+        && vertical_position == other.vertical_position);
 }
 
 ErrorOr<String> RadialGradientStyleValue::to_string() const
@@ -2240,7 +2212,7 @@ bool RadialGradientStyleValue::equals(StyleValue const& other) const
         return false;
     auto& other_gradient = other.as_radial_gradient();
     return (m_ending_shape == other_gradient.m_ending_shape
-        && variant_equals(m_size, other_gradient.m_size)
+        && m_size == other_gradient.m_size
         && m_position == other_gradient.m_position
         && m_color_stop_list == other_gradient.m_color_stop_list);
 }