layout: Take into account display: table etc in offset* queries (#32448)

* layout: Take into account `display: table` etc in offset* queries

The specification says that for deciding whether an element should be
used for offset* queries, a browser should take into account whether the
element is a table cell or table. This change makes that happen.

Co-authored-by: Oriol Brufau <obrufau@igalia.com>

* Only tag HTML elements if they are in the HTML namespace

---------

Co-authored-by: Oriol Brufau <obrufau@igalia.com>
This commit is contained in:
Martin Robinson 2024-06-10 17:05:57 +02:00 committed by GitHub
parent 35bbcc0d95
commit f4c9b310d5
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
11 changed files with 60 additions and 127 deletions

View file

@ -89,14 +89,21 @@ where
});
let threadsafe_node = node.to_threadsafe();
let flags = match threadsafe_node.as_element() {
Some(element) if element.is_body_element_of_html_element_root() => {
FragmentFlags::IS_BODY_ELEMENT_OF_HTML_ELEMENT_ROOT
},
Some(element) if element.get_local_name() == &local_name!("br") => {
FragmentFlags::IS_BR_ELEMENT
},
_ => FragmentFlags::empty(),
let mut flags = FragmentFlags::empty();
if let Some(element) = threadsafe_node.as_html_element() {
if element.is_body_element_of_html_element_root() {
flags.insert(FragmentFlags::IS_BODY_ELEMENT_OF_HTML_ELEMENT_ROOT);
}
match element.get_local_name() {
&local_name!("br") => {
flags.insert(FragmentFlags::IS_BR_ELEMENT);
},
&local_name!("table") | &local_name!("th") | &local_name!("td") => {
flags.insert(FragmentFlags::IS_TABLE_TH_OR_TD_ELEMENT);
},
_ => {},
}
};
Self {

View file

@ -88,15 +88,19 @@ bitflags! {
const IS_BODY_ELEMENT_OF_HTML_ELEMENT_ROOT = 0b00000001;
/// Whether or not the node that created this Fragment is a `<br>` element.
const IS_BR_ELEMENT = 0b00000010;
/// Whether or not the node that created was a `<table>`, `<th>` or
/// `<td>` element. Note that this does *not* include elements with
/// `display: table` or `display: table-cell`.
const IS_TABLE_TH_OR_TD_ELEMENT = 0b00000100;
/// Whether or not this Fragment was created to contain a replaced element or is
/// a replaced element.
const IS_REPLACED = 0b00000100;
const IS_REPLACED = 0b00001000;
/// Whether or not this Fragment was created to contain a list item marker
/// with a used value of `list-style-position: outside`.
const IS_OUTSIDE_LIST_ITEM_MARKER = 0b00001000;
const IS_OUTSIDE_LIST_ITEM_MARKER = 0b00010000;
/// Avoid painting the fragment, this is used for empty table cells when 'empty-cells' is 'hide'.
/// This flag doesn't avoid hit-testing.
const DO_NOT_PAINT = 0b00010000;
const DO_NOT_PAINT = 0b00100000;
}
}

View file

@ -31,7 +31,7 @@ use style::traversal::resolve_style;
use style::values::generics::font::LineHeight;
use style_traits::{ParsingMode, ToCss};
use crate::fragment_tree::{Fragment, FragmentFlags, FragmentTree, Tag};
use crate::fragment_tree::{BoxFragment, Fragment, FragmentFlags, FragmentTree, Tag};
pub fn process_content_box_request(
requested_node: OpaqueNode,
@ -428,24 +428,7 @@ fn process_offset_parent_query_inner(
// Record the paths of the nodes being traversed.
let parent_node_address = match fragment {
Fragment::Box(fragment) | Fragment::Float(fragment) => {
let is_eligible_parent =
match (is_body_element, fragment.style.get_box().position) {
// Spec says the element is eligible as `offsetParent` if any of
// these are true:
// 1) Is the body element
// 2) Is static position *and* is a table or table cell
// 3) Is not static position
// TODO: Handle case 2
(true, _) |
(false, Position::Absolute) |
(false, Position::Fixed) |
(false, Position::Relative) |
(false, Position::Sticky) => true,
// Otherwise, it's not a valid parent
(false, Position::Static) => false,
};
let is_eligible_parent = is_eligible_parent(fragment);
match base.tag {
Some(tag) if is_eligible_parent && !tag.is_pseudo() => Some(tag.node),
_ => None,
@ -531,6 +514,29 @@ fn process_offset_parent_query_inner(
})
}
/// Returns whether or not the element with the given style and body element determination
/// is eligible to be a parent element for offset* queries.
///
/// From <https://www.w3.org/TR/cssom-view-1/#dom-htmlelement-offsetparent>:
/// >
/// > Return the nearest ancestor element of the element for which at least one of the following is
/// > true and terminate this algorithm if such an ancestor is found:
/// > 1. The computed value of the position property is not static.
/// > 2. It is the HTML body element.
/// > 3. The computed value of the position property of the element is static and the ancestor is
/// > one of the following HTML elements: td, th, or table.
fn is_eligible_parent(fragment: &BoxFragment) -> bool {
fragment
.base
.flags
.contains(FragmentFlags::IS_BODY_ELEMENT_OF_HTML_ELEMENT_ROOT) ||
fragment.style.get_box().position != Position::Static ||
fragment
.base
.flags
.contains(FragmentFlags::IS_TABLE_TH_OR_TD_ELEMENT)
}
// https://html.spec.whatwg.org/multipage/#the-innertext-idl-attribute
pub fn process_element_inner_text_query<'dom>(_node: impl LayoutNode<'dom>) -> String {
"".to_owned()