fix(layout): adapt WPT input to explicit published snapshots

moli-layout/src/layout_tree/tree.rs

@@ -117,6 +117,30 @@ impl<N> FrozenLayoutTree<N>
 where
     N: Copy + Debug + Eq + Hash,
 {
+    /// Retains a published viewport for an embedded Document without a root
+    /// element. The document identity is its source, and no box can receive
+    /// input or provide element geometry until a later layout is published.
+    pub fn empty_viewport(source_root: N, viewport: LayoutViewport) -> Self {
+        Self::new(
+            source_root,
+            viewport,
+            LayoutPoint::ZERO,
+            LayoutSize::new(viewport.css_width as f32, viewport.css_height as f32),
+            LayoutOutputBoxId::from_index(0),
+            Vec::new(),
+            Vec::new(),
+            Vec::new(),
+            FrozenCoordinateSpace {
+                owner: None,
+                local_to_viewport: super::model::LayoutTransform2D::IDENTITY,
+                local_to_viewport_ignoring_css_transforms:
+                    super::model::LayoutTransform2D::IDENTITY,
+            },
+            Vec::new(),
+            Vec::new(),
+        )
+    }
+
     /// Source root whose complete layout projection this member tree owns.
     pub const fn source_root(&self) -> N {
         self.source_root

moli-protocol/src/domains/page/tests/same_document_history/hyperlink_navigation.rs

@@ -14,6 +14,7 @@ async fn activate(
     ))
     .await;
     if matches!(mode, "trusted" | "location" | "nested-click") {
+        page.command("Page.captureScreenshot", json!({})).await;
         for (kind, buttons) in [("mousePressed", 1), ("mouseReleased", 0)] {
             page.command("Input.dispatchMouseEvent", json!({
                 "type": kind, "x": 20, "y": 20, "button": "left", "buttons": buttons, "clickCount": 1,

moli-protocol/src/domains/page/tests/same_document_history/navigation_focus.rs

@@ -162,6 +162,7 @@ async fn navigation_focus_reset_respects_document_policy_and_manual_focus() {
             .await;
             // Establish the parent's focus with real input even though its
             // policy also denies script-initiated focus without activation.
+            page.command("Page.captureScreenshot", json!({})).await;
             for (kind, buttons) in [("mousePressed", 1), ("mouseReleased", 0)] {
                 page.command("Input.dispatchMouseEvent", json!({
                     "type": kind, "x": 310, "y": 10, "button": "left", "buttons": buttons, "clickCount": 1,
@@ -201,6 +202,7 @@ async fn navigation_focus_reset_preserves_trusted_initiation_after_activation_ex
         "{PROBE}\nsetupNavigationFocusProbe(true, \"'none'\")"
     ))
     .await;
+    page.command("Page.captureScreenshot", json!({})).await;
     for (kind, buttons) in [("mousePressed", 1), ("mouseReleased", 0)] {
         page.command("Input.dispatchMouseEvent", json!({
             "type": kind, "x": 20, "y": 20, "button": "left", "buttons": buttons, "clickCount": 1,

moli-renderer-v8/src/context_bootstrap/range_algorithms/text.rs

@@ -2,8 +2,7 @@ use super::ordering::point_order_handles;
 use super::*;
 use crate::native_bridge::document::XHTML_NS;
 use crate::native_bridge::element::{
-    StyleMode, observable_sources_with_fragments,
-    style_property_value,
+    StyleMode, observable_sources_with_fragments, style_property_value,
 };
 use crate::util::string_from_utf16_units_lossy;
 use std::{cmp::Ordering, collections::HashSet};

moli-renderer-v8/src/layout_renderer/mod.rs

@@ -108,7 +108,13 @@ impl EmbeddedFrameRenderer<DomHandle> for NativeEmbeddedFrameRenderer<'_> {
             .dom()
             .document_element_handle_for_document(document)
         else {
-            return Ok(None);
+            return Ok(Some(moli_layout::EmbeddedFrameSnapshot::new(
+                moli_layout::FrozenLayoutTree::empty_viewport(document, viewport),
+                self.capture_paint.then(|| {
+                    moli_layout::PaintSnapshot::new(viewport, moli_layout::PaintColor::TRANSPARENT)
+                }),
+                Vec::new(),
+            )));
         };
         let mut services = self
             .embedded_document_services

moli-renderer-v8/src/native_bridge/context_host/layout.rs

@@ -477,12 +477,13 @@ impl JsContextHost {
         let root = self
             .dom_host()
             .dom()
-            .document_element_handle_for_document(document);
+            .document_element_handle_for_document(document)
+            .unwrap_or(document);
         let state = self.document_layout_state.borrow();
         state
             .latest_layout(document)
-            .or_else(|| root.and_then(|root| state.latest_layout_for_root(root)))
-            .filter(|tree| Some(tree.source_root()) == root)
+            .or_else(|| state.latest_layout_for_root(root))
+            .filter(|tree| tree.source_root() == root)
             .map(inspect)
     }
 

moli-renderer-v8/src/native_bridge/document/hit_test.rs

@@ -558,7 +558,6 @@ fn element_at_point(
             document,
             moli_layout::LayoutPoint::new(x as f32, y as f32),
             false,
-            moli_layout::LayoutFlushReason::HitTest,
         )?;
         if let Some(element) = hits.into_iter().find_map(|hit| {
             let element = element_for_hit_source(runtime, hit.source)?;

moli-renderer-v8/src/native_bridge/element/activation/default_action.rs

@@ -24,13 +24,11 @@ use super::super::forms::{
 use super::super::{
     NodePublicEventDispatchOutcome, TextEditInputType, cache_input_files_from_selected_files,
     closed_details_ancestors_to_reveal, construct_click_event_with_detail_and_modifiers,
-    construct_command_event,
-    construct_input_event, construct_simple_event, contenteditable_editing_host,
-    dispatch_beforeinput, dispatch_popover_hide_events, dispatch_popover_show_events,
-    dispatch_popover_toggle_events,
-    dispatch_public_event, element_attribute, element_has_attribute, form_associated_form_owner,
-    is_disabled_form_control, is_focusable, is_valid_submit_button,
-    label_activation_control_handle,
+    construct_command_event, construct_input_event, construct_simple_event,
+    contenteditable_editing_host, dispatch_beforeinput, dispatch_popover_hide_events,
+    dispatch_popover_show_events, dispatch_popover_toggle_events, dispatch_public_event,
+    element_attribute, element_has_attribute, form_associated_form_owner, is_disabled_form_control,
+    is_focusable, is_valid_submit_button, label_activation_control_handle,
     perform_popover_invoker_default_action, perform_summary_click_default_action,
     replace_text_control_selection, resolve_url_like_attribute,
     resolved_reflected_element_attribute_handle, scroll_node_into_view_at_start,

moli-renderer-v8/src/native_bridge/element/content.rs

@@ -13,7 +13,7 @@ use super::super::{
     JsContextHost, document::set_detached_text_replacement_value,
     node::node_runtime_and_handle_from_object_or_detached, throw_dom_exception,
 };
-use super::geometry::observable_client_rects;
+use super::geometry::read_client_rects;
 use super::{
     html_element_getter_receiver, html_element_setter_receiver, observable_sources_with_fragments,
     property_string_value,
@@ -832,12 +832,7 @@ fn node_inner_text(
         && rendered_state
             .target_style()
             .is_some_and(|style| style.display != ComputedDisplayKind::Contents)
-        && observable_client_rects(
-            runtime,
-            handle,
-            moli_layout::LayoutFlushReason::SynchronousGeometry,
-        )?
-        .is_empty()
+        && read_client_rects(runtime, handle)?.is_empty()
     {
         return Ok(node.text_content(runtime.dom_host().dom()));
     }

moli-renderer-v8/src/native_bridge/element/forms/text_control.rs

@@ -8,8 +8,7 @@ pub(crate) use events::{
     dispatch_text_control_event, queue_text_control_document_selection_change_event,
 };
 pub(crate) use selection::{
-    replace_text_control_selection,
-    text_control_set_selection_range_internal,
+    replace_text_control_selection, text_control_set_selection_range_internal,
     text_control_set_selection_range_with_direction_internal,
 };
 pub(in crate::native_bridge) use selection::{

moli-renderer-v8/src/native_bridge/element/geometry.rs

@@ -11,8 +11,8 @@ pub use client_rect::ClientRect;
 #[cfg(test)]
 pub(crate) use hit_test::observable_scrollbar_hit_test;
 pub(crate) use hit_test::{
-    element_is_inert_for_hit_testing, InputSurfaceHit, input_surface_hit_test, observable_deep_hit_test, observable_hit_test,
-    observable_input_hit_test,
+    InputSurfaceHit, element_is_inert_for_hit_testing, input_surface_hit_test,
+    observable_deep_hit_test, observable_hit_test, observable_input_hit_test,
 };
 pub(in crate::native_bridge) use metrics::{
     node_client_height_getter_function, node_client_left_getter_function,

moli-renderer-v8/src/native_bridge/element/geometry/hit_test.rs

@@ -1,6 +1,7 @@
 use moli_layout::{
     FrozenLayoutTree, LayoutControlSurfaceHit, LayoutError, LayoutHit, LayoutPaintedSurfaceHit,
-    LayoutPoint, LayoutQuery, LayoutQueryAnswer, LayoutQueryBatch, LayoutTransform2D, LayoutViewport,
+    LayoutPoint, LayoutQuery, LayoutQueryAnswer, LayoutQueryBatch, LayoutTransform2D,
+    LayoutViewport,
 };
 
 #[cfg(test)]
@@ -114,11 +115,9 @@ pub(crate) fn observable_scrollbar_hit_test(
     document: DomHandle,
     point: LayoutPoint,
 ) -> Result<Option<LayoutScrollbarHit<DomHandle>>, LayoutError> {
-    input_surface_hit_test(runtime, document, point, false, true).map(|hit| {
-        match hit.control {
-            Some(LayoutControlSurfaceHit::Scrollbar(scrollbar)) => Some(scrollbar),
-            Some(LayoutControlSurfaceHit::ScrollbarCorner(_)) | None => None,
-        }
+    input_surface_hit_test(runtime, document, point, false, true).map(|hit| match hit.control {
+        Some(LayoutControlSurfaceHit::Scrollbar(scrollbar)) => Some(scrollbar),
+        Some(LayoutControlSurfaceHit::ScrollbarCorner(_)) | None => None,
     })
 }
 
@@ -165,13 +164,7 @@ pub(crate) fn observable_deep_hit_test(
     point: LayoutPoint,
     ignore_pointer_events_none: bool,
 ) -> Result<Option<DomHandle>, LayoutError> {
-    let hit = input_surface_hit_test(
-        runtime,
-        document,
-        point,
-        ignore_pointer_events_none,
-        false,
-    )?;
+    let hit = input_surface_hit_test(runtime, document, point, ignore_pointer_events_none, false)?;
     Ok(hit.document_or_element().map(|input| input.handle))
 }
 
@@ -322,7 +315,8 @@ fn input_surface_hit_test_in_tree(
         .dom_host()
         .dom()
         .document_element_handle_for_document(child_document)
-        != Some(child_tree.source_root())
+        .unwrap_or(child_document)
+        != child_tree.source_root()
     {
         return Err(LayoutError::NoLayoutSnapshot);
     }

moli-renderer-v8/src/script_vm/input_dispatch.rs

@@ -25,9 +25,9 @@ use crate::native_bridge::element::{
     construct_pointer_event_with_related_target_and_modifiers, construct_simple_event,
     construct_touch_event, construct_touch_event_with_points, construct_wheel_event,
     contenteditable_editing_host, dispatch_public_event, input_surface_hit_test, is_text_control,
-    observable_input_hit_test, perform_auxiliary_link_default_action, perform_drop_default_action,
+    observable_input_hit_test, perform_auxiliary_link_default_action,
+    perform_clipboard_key_default_action, perform_drop_default_action,
     perform_implicit_submission_from_control, perform_mouse_focus_default_action,
-    perform_clipboard_key_default_action,
     perform_scrollbar_scroll_default_action, perform_wheel_scroll_default_action,
     replace_contenteditable_selection, replace_text_control_selection,
     select_contenteditable_contents, text_control_set_selection_range_internal,

moli-renderer-v8/src/script_vm/tests/browser_api/clipboard_exec_copy.rs

@@ -18,6 +18,7 @@ navigator.clipboard.writeText('seed');'ready'
 }
 
 fn activated_copy_eval(vm: &mut StandaloneScriptVmHarness, script: &str) -> String {
+    vm.publish_layout_for_test().unwrap();
     vm._context_host
         .borrow_mut()
         .begin_protocol_user_gesture_activation();

moli-renderer-v8/src/script_vm/tests/close_watchers.rs

@@ -338,6 +338,7 @@ fn close_watcher_mouse_and_touch_activate_at_their_respective_input_phases() {
         setup_close_watcher_input_document(&mut vm);
         vm.eval("record('first').oncancel = e => e.preventDefault()")
             .unwrap();
+        vm.publish_layout_for_test().unwrap();
         if touch {
             vm.dispatch_touch_event_at_point(10.0, 11.0, "touchstart", false)
                 .unwrap();

moli-renderer-v8/src/script_vm/tests/dom_elements/dom_surface/extracted/geometry_and_scrolling.rs

@@ -1425,6 +1425,7 @@ fn single_line_text_input_preserves_programmatic_scroll_across_select() {
     )
     .expect("the previous text input should be replaced");
 
+    refresh_layout_for_test(&mut vm);
     vm.eval("__scrollInput.scrollLeft = 33")
         .expect("text input should accept a programmatic scroll");
     refresh_layout_for_test(&mut vm);

moli-renderer-v8/src/script_vm/tests/dom_elements/viewport_input.rs

@@ -15,7 +15,6 @@ fn viewport_input_vm() -> StandaloneScriptVmHarness {
         ..Default::default()
     }))
     .unwrap();
-    vm.force_fresh_layout_reads_for_test();
     vm.eval(
         r#"
         if (!document.documentElement) document.appendChild(document.createElement('html'));
@@ -37,6 +36,7 @@ fn viewport_input_vm() -> StandaloneScriptVmHarness {
 }
 
 fn click_viewport(vm: &mut StandaloneScriptVmHarness, x: f64, y: f64) {
+    vm.publish_layout_for_test().unwrap();
     for (event, button, buttons) in [("mousemove", -1, 0), ("mousedown", 0, 1), ("mouseup", 0, 0)] {
         vm.dispatch_mouse_event_at_point(x, y, event, button, Some(buttons), 0.0, 0.0)
             .unwrap();
@@ -240,6 +240,7 @@ fn viewport_root_input_wheel_keeps_child_target_and_chains_at_boundaries() {
         )
         .unwrap();
         vm.eval(setup).unwrap();
+        vm.publish_layout_for_test().unwrap();
         vm.dispatch_mouse_event_at_point(80.0, 80.0, "wheel", -1, Some(0), 0.0, 120.0)
             .unwrap();
         let actual = vm
@@ -256,3 +257,46 @@ fn viewport_root_input_wheel_keeps_child_target_and_chains_at_boundaries() {
         );
     }
 }
+
+#[test]
+fn viewport_root_input_requires_republication_when_an_empty_child_gains_a_root() {
+    let mut vm = viewport_input_vm();
+    vm.eval(
+        r#"
+        globalThis.frame = document.createElement('iframe');
+        frame.style.cssText = 'position:fixed;left:40px;top:40px;width:200px;height:50px;border:4px solid black';
+        document.body.appendChild(frame);
+        frame.contentDocument.documentElement.remove();
+        recordViewportClicks(frame.contentWindow, 'child');
+        "#,
+    )
+    .unwrap();
+    click_viewport(&mut vm, 80.0, 80.0);
+    assert_eq!(vm.eval("viewportClicks.length").unwrap(), "0");
+
+    vm.eval(
+        r#"
+        const child = frame.contentDocument;
+        const root = child.createElement('html');
+        root.style.cssText = 'margin:0;padding:0;height:0';
+        child.appendChild(root);
+        "#,
+    )
+    .unwrap();
+    let before = vm.layout_pass_observability_for_test().1;
+    let error = vm
+        .dispatch_mouse_event_at_point(80.0, 80.0, "mousedown", 0, Some(1), 0.0, 0.0)
+        .unwrap_err();
+    assert_eq!(
+        error.downcast_ref::<moli_layout::LayoutError>(),
+        Some(&moli_layout::LayoutError::NoLayoutSnapshot)
+    );
+    assert_eq!(vm.layout_pass_observability_for_test().1, before);
+    assert_eq!(vm.pressed_mouse_buttons, 0);
+    assert!(vm.pending_mouse_press.is_none());
+    click_viewport(&mut vm, 80.0, 80.0);
+    assert_eq!(
+        vm.eval("JSON.stringify(viewportClicks)").unwrap(),
+        r#"[["child","HTML",36,36,true]]"#
+    );
+}

moli-renderer-v8/src/script_vm/tests/dom_xhr/dom/dom_parser.rs

@@ -618,6 +618,7 @@ html, body { margin: 0; }
 <div id="under"></div><div id="container"><div id="target"></div></div>"#,
     );
 
+    vm.publish_layout_for_test().unwrap();
     let result = vm
         .eval(
             r#"
@@ -635,13 +636,32 @@ html, body { margin: 0; }
   container.inert = false;
   values.push(top() === target);
 
-  const svg = document.createElementNS('http://www.w3.org/2000/svg', 'svg');
+  return values.join('|');
+})()
+"#,
+        )
+        .expect("dynamic inert point-query probe should evaluate");
+    assert_eq!(result, "true|under|under,html|true");
+
+    vm.eval(
+        r#"
+  globalThis.svg = document.createElementNS('http://www.w3.org/2000/svg', 'svg');
   svg.setAttribute('style', 'position:fixed;inset:0;width:100px;height:100px');
   const rect = document.createElementNS(svg.namespaceURI, 'rect');
   rect.setAttribute('width', '100');
   rect.setAttribute('height', '100');
   svg.appendChild(rect);
   document.body.appendChild(svg);
+"#,
+    )
+    .unwrap();
+    vm.publish_layout_for_test().unwrap();
+    let result = vm
+        .eval(
+            r#"(() => {
+  const top = () => document.elementFromPoint(1, 1);
+  const target = document.getElementById('target');
+  const values = [];
   const svgHit = top();
   svg.setAttribute('inert', '');
   values.push(top() === svgHit);
@@ -657,5 +677,5 @@ html, body { margin: 0; }
         )
         .expect("dynamic inert point-query probe should evaluate");
 
-    assert_eq!(result, "true|under|under,html|true|true|true");
+    assert_eq!(result, "true|true");
 }

moli-renderer-v8/src/script_vm/tests/dom_xhr/misc.rs

@@ -1955,6 +1955,8 @@ fn dom_rect_list_has_readonly_indexed_semantics_and_rejects_structured_clone() {
         "<!doctype html><body><div id='node'>text</div></body>",
     );
 
+    vm.publish_layout_for_test().unwrap();
+
     let result = vm
         .eval(
             r#"

moli-renderer-v8/src/script_vm/tests/element_click.rs

@@ -19,7 +19,7 @@ fn native_element_click_initializes_layout_once() {
 }
 
 #[test]
-fn native_element_click_refreshes_stale_layout_after_dom_and_style_changes() {
+fn native_element_click_reads_explicitly_republished_layout_after_dom_and_style_changes() {
     for mutation in [
         "target.style.left='300px'",
         "const veil=document.createElement('div');veil.style.cssText='position:fixed;inset:0;z-index:999';document.body.appendChild(veil)",
@@ -55,11 +55,18 @@ fn native_element_click_refreshes_stale_layout_after_dom_and_style_changes() {
                 "(()=>{{const target=document.getElementById('target');{mutation}}})()"
             ))
             .expect("mutate live DOM/style before preparing another click");
+            let _ = vm.prepare_element_click(target);
+            assert_eq!(
+                vm.layout_pass_observability_for_test().1,
+                before + 1,
+                "click preparation must not publish changed DOM or style"
+            );
+            publish_layout_for_test(&mut vm);
             let prepared = vm.prepare_element_click(target);
             let prepared_passes = vm.layout_pass_observability_for_test().1;
             assert!(
                 prepared_passes > before + 1,
-                "a changed DOM or style must refresh the shared geometry snapshot: {mutation}"
+                "explicit publication must refresh the shared geometry snapshot: {mutation}"
             );
             if mutation != "target.style.left='300px'" {
                 assert!(
@@ -107,8 +114,8 @@ fn native_element_click_refreshes_stale_layout_after_dom_and_style_changes() {
             }
             let passes = vm.layout_pass_observability_for_test().1 - before;
             assert_eq!(
-                passes, 1,
-                "the entire mouse sequence must reuse one snapshot: {mutation}"
+                passes, 2,
+                "the entire mouse sequence must reuse the republished snapshot: {mutation}"
             );
             let events = vm.eval("JSON.stringify([clicks,events])").unwrap();
             if let Some((existing_passes, existing_events)) = &reference {