1 files changed, 129 insertions, 0 deletions
diff --git a/components/layout_2020/flow/root.rs b/components/layout_2020/flow/root.rs
new file mode 100644
index 00000000000..08a23397506
--- /dev/null
+++ b/components/layout_2020/flow/root.rs
@@ -0,0 +1,129 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use super::*;
+
+// FIXME
+// impl crate::dom::Document {
+//     pub(crate) fn layout(
+//         &self,
+//         viewport: crate::geom::Size<crate::geom::CssPx>,
+//     ) -> Vec<Fragment> {
+//         BoxTreeRoot::construct(self).layout(viewport)
+//     }
+// }
+
+struct BoxTreeRoot(BlockFormattingContext);
+
+// FIXME
+// impl BoxTreeRoot {
+//     pub fn construct(document: &dom::Document) -> Self {
+//         let author_styles = &document.parse_stylesheets();
+//         let context = Context {
+//             document,
+//             author_styles,
+//         };
+//         let root_element = document.root_element();
+//         let style = style_for_element(context.author_styles, context.document, root_element, None);
+//         let (contains_floats, boxes) = construct_for_root_element(&context, root_element, style);
+//         Self(BlockFormattingContext {
+//             contains_floats: contains_floats == ContainsFloats::Yes,
+//             contents: BlockContainer::BlockLevelBoxes(boxes),
+//         })
+//     }
+// }
+
+// fn construct_for_root_element(
+//     context: &Context,
+//     root_element: dom::NodeId,
+//     style: Arc<ComputedValues>,
+// ) -> (ContainsFloats, Vec<Arc<BlockLevelBox>>) {
+//     let replaced = ReplacedContent::for_element(root_element, context);
+
+//     let display_inside = match style.box_.display {
+//         Display::None => return (ContainsFloats::No, Vec::new()),
+//         Display::Contents if replaced.is_some() => {
+//             // 'display: contents' computes to 'none' for replaced elements
+//             return (ContainsFloats::No, Vec::new());
+//         }
+//         // https://drafts.csswg.org/css-display-3/#transformations
+//         Display::Contents => DisplayInside::Flow,
+//         // The root element is blockified, ignore DisplayOutside
+//         Display::GeneratingBox(DisplayGeneratingBox::OutsideInside { inside, .. }) => inside,
+//     };
+
+//     if let Some(replaced) = replaced {
+//         let _box = match replaced {};
+//         #[allow(unreachable_code)]
+//         {
+//             return (ContainsFloats::No, vec![Arc::new(_box)]);
+//         }
+//     }
+
+//     let contents = IndependentFormattingContext::construct(
+//         context,
+//         &style,
+//         display_inside,
+//         Contents::OfElement(root_element),
+//     );
+//     if style.box_.position.is_absolutely_positioned() {
+//         (
+//             ContainsFloats::No,
+//             vec![Arc::new(BlockLevelBox::OutOfFlowAbsolutelyPositionedBox(
+//                 AbsolutelyPositionedBox { style, contents },
+//             ))],
+//         )
+//     } else if style.box_.float.is_floating() {
+//         (
+//             ContainsFloats::Yes,
+//             vec![Arc::new(BlockLevelBox::OutOfFlowFloatBox(FloatBox {
+//                 contents,
+//                 style,
+//             }))],
+//         )
+//     } else {
+//         (
+//             ContainsFloats::No,
+//             vec![Arc::new(BlockLevelBox::Independent { style, contents })],
+//         )
+//     }
+// }
+
+// impl BoxTreeRoot {
+//     fn layout(&self, viewport: crate::geom::Size<crate::geom::CssPx>) -> Vec<Fragment> {
+//         let initial_containing_block_size = Vec2 {
+//             inline: Length { px: viewport.width },
+//             block: Length {
+//                 px: viewport.height,
+//             },
+//         };
+
+//         let initial_containing_block = ContainingBlock {
+//             inline_size: initial_containing_block_size.inline,
+//             block_size: LengthOrAuto::Length(initial_containing_block_size.block),
+//             // FIXME: use the document’s mode:
+//             // https://drafts.csswg.org/css-writing-modes/#principal-flow
+//             mode: (WritingMode::HorizontalTb, Direction::Ltr),
+//         };
+//         let dummy_tree_rank = 0;
+//         let mut absolutely_positioned_fragments = vec![];
+//         let mut fragments = self.0.layout(
+//             &initial_containing_block,
+//             &mut absolutely_positioned_fragments,
+//             dummy_tree_rank,
+//             &mut PlacementState::root(),
+//         );
+
+//         let initial_containing_block = DefiniteContainingBlock {
+//             size: initial_containing_block_size,
+//             mode: initial_containing_block.mode,
+//         };
+//         fragments.par_extend(
+//             absolutely_positioned_fragments
+//                 .par_iter()
+//                 .map(|a| a.layout(&initial_containing_block)),
+//         );
+//         fragments
+//     }
+// }