summaryrefslogtreecommitdiffstats
path: root/servo/components/style_traits/dom.rs
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 17:32:43 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 17:32:43 +0000
commit6bf0a5cb5034a7e684dcc3500e841785237ce2dd (patch)
treea68f146d7fa01f0134297619fbe7e33db084e0aa /servo/components/style_traits/dom.rs
parentInitial commit. (diff)
downloadthunderbird-6bf0a5cb5034a7e684dcc3500e841785237ce2dd.tar.xz
thunderbird-6bf0a5cb5034a7e684dcc3500e841785237ce2dd.zip
Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'servo/components/style_traits/dom.rs')
-rw-r--r--servo/components/style_traits/dom.rs26
1 files changed, 26 insertions, 0 deletions
diff --git a/servo/components/style_traits/dom.rs b/servo/components/style_traits/dom.rs
new file mode 100644
index 0000000000..03d5264abf
--- /dev/null
+++ b/servo/components/style_traits/dom.rs
@@ -0,0 +1,26 @@
+/* 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/. */
+
+//! Types used to access the DOM from style calculation.
+
+/// An opaque handle to a node, which, unlike UnsafeNode, cannot be transformed
+/// back into a non-opaque representation. The only safe operation that can be
+/// performed on this node is to compare it to another opaque handle or to another
+/// OpaqueNode.
+///
+/// Layout and Graphics use this to safely represent nodes for comparison purposes.
+/// Because the script task's GC does not trace layout, node data cannot be safely stored in layout
+/// data structures. Also, layout code tends to be faster when the DOM is not being accessed, for
+/// locality reasons. Using `OpaqueNode` enforces this invariant.
+#[derive(Clone, Copy, Debug, Eq, Hash, MallocSizeOf, PartialEq)]
+#[cfg_attr(feature = "servo", derive(Deserialize, Serialize))]
+pub struct OpaqueNode(pub usize);
+
+impl OpaqueNode {
+ /// Returns the address of this node, for debugging purposes.
+ #[inline]
+ pub fn id(&self) -> usize {
+ self.0
+ }
+}