Auto merge of #19805 - emilio:doc-state-fix, r=xidorn

style: Handle correctly document state invalidation inside negation.

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components/selectors/context.rs

@@ -127,6 +127,9 @@ where
     /// MatchingContext immutable again.
     nesting_level: usize,
 
+    /// Whether we're inside a negation or not.
+    in_negation: bool,
+
     /// An optional hook function for checking whether a pseudo-element
     /// should match when matching_mode is ForStatelessPseudoElement.
     pub pseudo_element_matching_fn: Option<&'a Fn(&Impl::PseudoElement) -> bool>,
@@ -176,6 +179,7 @@ where
             classes_and_ids_case_sensitivity: quirks_mode.classes_and_ids_case_sensitivity(),
             scope_element: None,
             nesting_level: 0,
+            in_negation: false,
             pseudo_element_matching_fn: None,
             extra_data: Default::default(),
             _impl: ::std::marker::PhantomData,
@@ -188,6 +192,12 @@ where
         self.nesting_level != 0
     }
 
+    /// Whether we're matching inside a :not(..) selector.
+    #[inline]
+    pub fn in_negation(&self) -> bool {
+        self.in_negation
+    }
+
     /// The quirks mode of the document.
     #[inline]
     pub fn quirks_mode(&self) -> QuirksMode {
@@ -212,6 +222,23 @@ where
         result
     }
 
+    /// Runs F with a deeper nesting level, and marking ourselves in a negation,
+    /// for a :not(..) selector, for example.
+    #[inline]
+    pub fn nest_for_negation<F, R>(&mut self, f: F) -> R
+    where
+        F: FnOnce(&mut Self) -> R,
+    {
+        debug_assert!(
+            !self.in_negation,
+            "Someone messed up parsing?"
+        );
+        self.in_negation = true;
+        let result = self.nest(f);
+        self.in_negation = false;
+        result
+    }
+
     #[inline]
     pub fn visited_handling(&self) -> VisitedHandlingMode {
         self.visited_handling

components/selectors/matching.rs

@@ -625,6 +625,8 @@ where
     E: Element,
     F: FnMut(&E, ElementSelectorFlags),
 {
+    debug_assert!(context.shared.is_nested() || !context.shared.in_negation());
+
     match *selector {
         Component::Combinator(_) => unreachable!(),
         Component::Slotted(ref selector) => {
@@ -777,7 +779,7 @@ where
             matches_generic_nth_child(element, context, 0, 1, true, true, flags_setter)
         }
         Component::Negation(ref negated) => {
-            context.shared.nest(|context| {
+            context.shared.nest_for_negation(|context| {
                 let mut local_context = LocalMatchingContext {
                     matches_hover_and_active_quirk: MatchesHoverAndActiveQuirk::No,
                     shared: context,

components/style/gecko/generated/bindings.rs

@@ -1151,6 +1151,8 @@ extern "C" {
  pub fn Servo_Element_IsDisplayNone ( element : RawGeckoElementBorrowed , ) -> bool ; 
 } extern "C" {
  pub fn Servo_Element_IsPrimaryStyleReusedViaRuleNode ( element : RawGeckoElementBorrowed , ) -> bool ; 
+} extern "C" {
+ pub fn Servo_InvalidateStyleForDocStateChanges ( root : RawGeckoElementBorrowed , sets : * const nsTArray < RawServoStyleSetBorrowed > , aStatesChanged : u64 , ) ; 
 } extern "C" {
  pub fn Servo_StyleSheet_FromUTF8Bytes ( loader : * mut Loader , gecko_stylesheet : * mut ServoStyleSheet , data : * const u8 , data_len : usize , parsing_mode : SheetParsingMode , extra_data : * mut RawGeckoURLExtraData , line_number_offset : u32 , quirks_mode : nsCompatibility , reusable_sheets : * mut LoaderReusableStyleSheets , ) -> RawServoStyleSheetContentsStrong ; 
 } extern "C" {
@@ -1595,4 +1597,4 @@ extern "C" {
  pub fn Gecko_IsInServoTraversal ( ) -> bool ; 
 } extern "C" {
  pub fn Gecko_IsMainThread ( ) -> bool ; 
-}
+}

components/style/gecko/wrapper.rs

@@ -2111,7 +2111,7 @@ impl<'le> ::selectors::Element for GeckoElement<'le> {
             NonTSPseudoClass::MozWindowInactive => {
                 let state_bit = DocumentState::NS_DOCUMENT_STATE_WINDOW_INACTIVE;
                 if context.extra_data.document_state.intersects(state_bit) {
-                    return true;
+                    return !context.in_negation();
                 }
 
                 self.document_state().contains(state_bit)
@@ -2132,7 +2132,7 @@ impl<'le> ::selectors::Element for GeckoElement<'le> {
                 if context.extra_data.document_state.intersects(state_bit) {
                     // NOTE(emilio): We could still return false for
                     // Direction::Other(..), but we don't bother.
-                    return true;
+                    return !context.in_negation();
                 }
 
                 let doc_is_rtl = self.document_state().contains(state_bit);

ports/geckolib/tests/build.rs

@@ -39,6 +39,21 @@ fn main() {
         for line in r.lines() {
             let s = line.unwrap();
             for cap in matcher.captures_iter(&s) {
+                // This causes a mismatch in old libclangs (the ones that are
+                // used in linux32 mozilla-central) because it generates:
+                //
+                //   *const nsTArray<*const RawServoStyleSet>
+                //
+                // Instead of:
+                //
+                //   *const nsTArray<RawServoStyleSetBorrowed>
+                //
+                // Which is not a problem, but would cause this to not compile.
+                //
+                // Skip this until libclang is updated there.
+                if &cap[1] == "InvalidateStyleForDocStateChanges" {
+                    continue;
+                }
                 w.write_all(format!("    [ Servo_{0}, bindings::Servo_{0} ];\n", &cap[1]).as_bytes()).unwrap();
             }
         }