From 52f89c95b9decf86b445f311b8c04412d8c1754f Mon Sep 17 00:00:00 2001
From: Oriol Brufau <obrufau@igalia.com>
Date: Fri, 13 Sep 2024 12:47:50 +0200
Subject: [PATCH] Fix inset box-shadow to use the padding box (#33433)

As specified in https://drafts.csswg.org/css-backgrounds-3/#shadow-shape

Signed-off-by: Oriol Brufau <obrufau@igalia.com>
---
 components/layout_2020/display_list/mod.rs               | 9 ++++-----
 .../wpt/meta/css/css-backgrounds/box-shadow-041.html.ini | 2 --
 .../wpt/meta/css/css-backgrounds/box-shadow-042.html.ini | 2 --
 .../box-shadow-inset-without-border-radius.html.ini      | 2 --
 tests/wpt/meta/css/css-tables/box-shadow-001.html.ini    | 2 --
 5 files changed, 4 insertions(+), 13 deletions(-)
 delete mode 100644 tests/wpt/meta/css/css-backgrounds/box-shadow-041.html.ini
 delete mode 100644 tests/wpt/meta/css/css-backgrounds/box-shadow-042.html.ini
 delete mode 100644 tests/wpt/meta/css/css-backgrounds/box-shadow-inset-without-border-radius.html.ini
 delete mode 100644 tests/wpt/meta/css/css-tables/box-shadow-001.html.ini

diff --git a/components/layout_2020/display_list/mod.rs b/components/layout_2020/display_list/mod.rs
index c89a6f272ac..dcc912ef903 100644
--- a/components/layout_2020/display_list/mod.rs
+++ b/components/layout_2020/display_list/mod.rs
@@ -1028,18 +1028,17 @@ impl<'a> BuilderForBoxFragment<'a> {
         }
 
         // NB: According to CSS-BACKGROUNDS, box shadows render in *reverse* order (front to back).
-        let border_rect = self.border_rect;
         let common = builder.common_properties(MaxRect::max_rect(), &self.fragment.style);
         for box_shadow in box_shadows.iter().rev() {
-            let clip_mode = if box_shadow.inset {
-                BoxShadowClipMode::Inset
+            let (rect, clip_mode) = if box_shadow.inset {
+                (*self.padding_rect(), BoxShadowClipMode::Inset)
             } else {
-                BoxShadowClipMode::Outset
+                (self.border_rect, BoxShadowClipMode::Outset)
             };
 
             builder.wr().push_box_shadow(
                 &common,
-                border_rect,
+                rect,
                 LayoutVector2D::new(
                     box_shadow.base.horizontal.px(),
                     box_shadow.base.vertical.px(),
diff --git a/tests/wpt/meta/css/css-backgrounds/box-shadow-041.html.ini b/tests/wpt/meta/css/css-backgrounds/box-shadow-041.html.ini
deleted file mode 100644
index 8cc89a20010..00000000000
--- a/tests/wpt/meta/css/css-backgrounds/box-shadow-041.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[box-shadow-041.html]
-  expected: FAIL
diff --git a/tests/wpt/meta/css/css-backgrounds/box-shadow-042.html.ini b/tests/wpt/meta/css/css-backgrounds/box-shadow-042.html.ini
deleted file mode 100644
index 85fe3c5242e..00000000000
--- a/tests/wpt/meta/css/css-backgrounds/box-shadow-042.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[box-shadow-042.html]
-  expected: FAIL
diff --git a/tests/wpt/meta/css/css-backgrounds/box-shadow-inset-without-border-radius.html.ini b/tests/wpt/meta/css/css-backgrounds/box-shadow-inset-without-border-radius.html.ini
deleted file mode 100644
index 0e7d21410ad..00000000000
--- a/tests/wpt/meta/css/css-backgrounds/box-shadow-inset-without-border-radius.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[box-shadow-inset-without-border-radius.html]
-  expected: FAIL
diff --git a/tests/wpt/meta/css/css-tables/box-shadow-001.html.ini b/tests/wpt/meta/css/css-tables/box-shadow-001.html.ini
deleted file mode 100644
index fc97f559495..00000000000
--- a/tests/wpt/meta/css/css-tables/box-shadow-001.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[box-shadow-001.html]
-  expected: FAIL