Paint background color of root element over the entire canvas

servo · ferjm · Feb 15, 2018 · Feb 19, 2018 · 778ed018747fa8d584a21971e3d67056781090b3
commit 778ed018747fa8d584a21971e3d67056781090b3
diff --git a/components/layout/display_list/builder.rs b/components/layout/display_list/builder.rs
@@ -463,7 +463,8 @@ impl<'a> DisplayListBuildState<'a> {
         // refer to the steps in CSS 2.1 Appendix E.
         // Steps 1 and 2: Borders and background for the root.
         while child_items.last().map_or(false, |child| {
-            child.section() == DisplayListSection::BackgroundAndBorders
+            (child.section() == DisplayListSection::BackgroundAndBorders) ||
+            (child.section() == DisplayListSection::BlockBackgroundsAndBorders)
         }) {
             list.push(child_items.pop().unwrap());
         }

diff --git a/tests/wpt/mozilla/meta/MANIFEST.json b/tests/wpt/mozilla/meta/MANIFEST.json
@@ -319,6 +319,18 @@
      {}
     ]
    ],
+   "css/background_color_root_zindex.html": [
+    [
+     "/_mozilla/css/background_color_root_zindex.html",
+     [
+      [
+       "/_mozilla/css/background_color_root_zindex_ref.html",
+       "=="
+      ]
+     ],
+     {}
+    ]
+   ],
    "css/background_external_stylesheet.html": [
     [
      "/_mozilla/css/background_external_stylesheet.html",
@@ -8040,6 +8052,11 @@
      {}
     ]
    ],
+   "css/background_color_root_zindex_ref.html": [
+    [
+     {}
+    ]
+   ],
    "css/background_image_position_ref.html": [
     [
      {}

    "0e41943f5e91d9828c3eed9f990bed2c0758c6b7",
    "support"
   ],
+  "css/background_color_root_zindex.html": [
+   "a51fdd92212ec73a4350a15d7a956efb21bff0fd",
+   "reftest"
+  ],
+  "css/background_color_root_zindex_ref.html": [
+   "4e701ec8909e82dd2358b71c39093d6cfab60f09",
+   "support"
+  ],
   "css/background_external_stylesheet.html": [
    "5b4310d6eac77edd8c182c4fe854241737a2fb8f",
    "reftest"
diff --git a/tests/wpt/mozilla/tests/css/background_color_root_zindex.html b/tests/wpt/mozilla/tests/css/background_color_root_zindex.html
@@ -0,0 +1,14 @@
+<!doctype html>
+<meta charset="utf-8">
+<title>Ensure that background colour of root element is drawn above elements with negative z-index</title>
+<link rel="match" href="background_color_root_zindex_ref.html">
+<style>
+html {
+  background-color: #7d2663;
+}
+h1 {
+  position: absolute;
+  z-index: -1;
+}
+</style>
+<h1>You should see this text<h1>
diff --git a/tests/wpt/mozilla/tests/css/background_color_root_zindex_ref.html b/tests/wpt/mozilla/tests/css/background_color_root_zindex_ref.html
@@ -0,0 +1,12 @@
+<!doctype html>
+<meta charset="utf-8">
+<title>Ensure that background colour of root element is drawn above elements with negative z-index</title>
+<style>
+html {
+  background-color: #7d2663;
+}
+h1 {
+  position: absolute;
+}
+</style>
+<h1>You should see this text<h1>