Revert as many changes to selectors from upstream as possible (#31365)

This is part of the preparation for splitting stylo into a separate
crate. We have made various changes to selectors includings:

 1. Bumping the rust edition
 2. Fixing typos and updating links

In addition to reverting those changes, this PR pulls in some changes to
selectors we seem to have missed in the process of updates.

1 files changed, 22 insertions, 39 deletions

diff --git a/components/selectors/parser.rs b/components/selectors/parser.rs
index f9017b95b9b..2c44da8018e 100644
--- a/components/selectors/parser.rs
+++ b/components/selectors/parser.rs
@@ -14,21 +14,17 @@ use crate::sink::Push;
 use crate::visitor::SelectorListKind;
 pub use crate::visitor::SelectorVisitor;
 use bitflags::bitflags;
-use cssparser::{match_ignore_ascii_case, parse_nth};
+use cssparser::parse_nth;
 use cssparser::{BasicParseError, BasicParseErrorKind, ParseError, ParseErrorKind};
 use cssparser::{CowRcStr, Delimiter, SourceLocation};
 use cssparser::{Parser as CssParser, ToCss, Token};
-use debug_unreachable::debug_unreachable;
 use precomputed_hash::PrecomputedHash;
 use servo_arc::{HeaderWithLength, ThinArc, UniqueArc};
-use size_of_test::size_of_test;
 use smallvec::SmallVec;
 use std::borrow::{Borrow, Cow};
 use std::fmt::{self, Debug};
 use std::iter::Rev;
 use std::slice;
-#[cfg(feature = "shmem")]
-use to_shmem_derive::ToShmem;
 
 /// A trait that represents a pseudo-element.
 pub trait PseudoElement: Sized + ToCss {
@@ -168,8 +164,6 @@ impl SelectorParsingState {
 
 pub type SelectorParseError<'i> = ParseError<'i, SelectorParseErrorKind<'i>>;
 
-size_of_test!(SelectorParseError, 48);
-
 #[derive(Clone, Debug, PartialEq)]
 pub enum SelectorParseErrorKind<'i> {
     NoQualifiedNameInAttributeSelector(Token<'i>),
@@ -194,8 +188,6 @@ pub enum SelectorParseErrorKind<'i> {
     ClassNeedsIdent(Token<'i>),
 }
 
-size_of_test!(SelectorParseErrorKind, 40);
-
 macro_rules! with_all_bounds {
     (
         [ $( $InSelector: tt )* ]
@@ -298,9 +290,6 @@ pub trait Parser<'i> {
         true
     }
 
-    /// Parses non-tree-structural pseudo-classes. Tree structural pseudo-classes,
-    /// like `:first-child`, are built into this library.
-    ///
     /// This function can return an "Err" pseudo-element in order to support CSS2.1
     /// pseudo-elements.
     fn parse_non_ts_pseudo_class(
@@ -363,11 +352,10 @@ pub trait Parser<'i> {
     }
 }
 
-#[derive(Clone, Debug, Eq, PartialEq)]
-#[cfg_attr(feature = "shmem", derive(ToShmem))]
-#[cfg_attr(feature = "shmem", shmem(no_bounds))]
+#[derive(Clone, Debug, Eq, PartialEq, ToShmem)]
+#[shmem(no_bounds)]
 pub struct SelectorList<Impl: SelectorImpl>(
-    #[cfg_attr(feature = "shmem", shmem(field_bound))] pub SmallVec<[Selector<Impl>; 1]>,
+    #[shmem(field_bound)] pub SmallVec<[Selector<Impl>; 1]>,
 );
 
 /// Whether or not we're using forgiving parsing mode
@@ -643,12 +631,10 @@ pub fn namespace_empty_string<Impl: SelectorImpl>() -> Impl::NamespaceUrl {
 ///
 /// This reordering doesn't change the semantics of selector matching, and we
 /// handle it in to_css to make it invisible to serialization.
-#[derive(Clone, Eq, PartialEq)]
-#[cfg_attr(feature = "shmem", derive(ToShmem))]
-#[cfg_attr(feature = "shmem", shmem(no_bounds))]
+#[derive(Clone, Eq, PartialEq, ToShmem)]
+#[shmem(no_bounds)]
 pub struct Selector<Impl: SelectorImpl>(
-    #[cfg_attr(feature = "shmem", shmem(field_bound))]
-    ThinArc<SpecificityAndFlags, Component<Impl>>,
+    #[shmem(field_bound)] ThinArc<SpecificityAndFlags, Component<Impl>>,
 );
 
 impl<Impl: SelectorImpl> Selector<Impl> {
@@ -1299,8 +1285,7 @@ impl<'a, Impl: SelectorImpl> Iterator for AncestorIter<'a, Impl> {
     }
 }
 
-#[derive(Clone, Copy, Debug, Eq, PartialEq)]
-#[cfg_attr(feature = "shmem", derive(ToShmem))]
+#[derive(Clone, Copy, Debug, Eq, PartialEq, ToShmem)]
 pub enum Combinator {
     Child,        //  >
     Descendant,   // space
@@ -1541,10 +1526,10 @@ impl CombinatorComposition {
         for combinator in CombinatorIter::new(inner_selector.iter_skip_relative_selector_anchor()) {
             match combinator {
                 Combinator::Descendant | Combinator::Child => {
-                    result.insert(CombinatorComposition::DESCENDANTS);
+                    result.insert(Self::DESCENDANTS);
                 },
                 Combinator::NextSibling | Combinator::LaterSibling => {
-                    result.insert(CombinatorComposition::SIBLINGS);
+                    result.insert(Self::SIBLINGS);
                 },
                 Combinator::Part | Combinator::PseudoElement | Combinator::SlotAssignment => {
                     continue
@@ -1637,17 +1622,16 @@ impl<Impl: SelectorImpl> RelativeSelector<Impl> {
 /// optimal packing and cache performance, see [1].
 ///
 /// [1] https://bugzilla.mozilla.org/show_bug.cgi?id=1357973
-#[derive(Clone, Eq, PartialEq)]
-#[cfg_attr(feature = "shmem", derive(ToShmem))]
-#[cfg_attr(feature = "shmem", shmem(no_bounds))]
+#[derive(Clone, Eq, PartialEq, ToShmem)]
+#[shmem(no_bounds)]
 pub enum Component<Impl: SelectorImpl> {
     LocalName(LocalName<Impl>),
 
-    ID(#[cfg_attr(feature = "shmem", shmem(field_bound))] Impl::Identifier),
-    Class(#[cfg_attr(feature = "shmem", shmem(field_bound))] Impl::Identifier),
+    ID(#[shmem(field_bound)] Impl::Identifier),
+    Class(#[shmem(field_bound)] Impl::Identifier),
 
     AttributeInNoNamespaceExists {
-        #[cfg_attr(feature = "shmem", shmem(field_bound))]
+        #[shmem(field_bound)]
         local_name: Impl::LocalName,
         local_name_lower: Impl::LocalName,
     },
@@ -1655,7 +1639,7 @@ pub enum Component<Impl: SelectorImpl> {
     AttributeInNoNamespace {
         local_name: Impl::LocalName,
         operator: AttrSelectorOperator,
-        #[cfg_attr(feature = "shmem", shmem(field_bound))]
+        #[shmem(field_bound)]
         value: Impl::AttrValue,
         case_sensitivity: ParsedCaseSensitivity,
     },
@@ -1680,7 +1664,7 @@ pub enum Component<Impl: SelectorImpl> {
     ParentSelector,
     Nth(NthSelectorData),
     NthOf(NthOfSelectorData<Impl>),
-    NonTSPseudoClass(#[cfg_attr(feature = "shmem", shmem(field_bound))] Impl::NonTSPseudoClass),
+    NonTSPseudoClass(#[shmem(field_bound)] Impl::NonTSPseudoClass),
     /// The ::slotted() pseudo-element:
     ///
     /// https://drafts.csswg.org/css-scoping/#slotted-pseudo
@@ -1695,7 +1679,7 @@ pub enum Component<Impl: SelectorImpl> {
     Slotted(Selector<Impl>),
     /// The `::part` pseudo-element.
     ///   https://drafts.csswg.org/css-shadow-parts/#part
-    Part(#[cfg_attr(feature = "shmem", shmem(field_bound))] Box<[Impl::Identifier]>),
+    Part(#[shmem(field_bound)] Box<[Impl::Identifier]>),
     /// The `:host` pseudo-class:
     ///
     /// https://drafts.csswg.org/css-scoping/#host-selector
@@ -1726,7 +1710,7 @@ pub enum Component<Impl: SelectorImpl> {
     /// Same comment as above re. the argument.
     Has(Box<[RelativeSelector<Impl>]>),
     /// An implementation-dependent pseudo-element selector.
-    PseudoElement(#[cfg_attr(feature = "shmem", shmem(field_bound))] Impl::PseudoElement),
+    PseudoElement(#[shmem(field_bound)] Impl::PseudoElement),
 
     Combinator(Combinator),
 
@@ -1886,11 +1870,10 @@ impl<Impl: SelectorImpl> Component<Impl> {
     }
 }
 
-#[derive(Clone, Eq, PartialEq)]
-#[cfg_attr(feature = "shmem", derive(ToShmem))]
-#[cfg_attr(feature = "shmem", shmem(no_bounds))]
+#[derive(Clone, Eq, PartialEq, ToShmem)]
+#[shmem(no_bounds)]
 pub struct LocalName<Impl: SelectorImpl> {
-    #[cfg_attr(feature = "shmem", shmem(field_bound))]
+    #[shmem(field_bound)]
     pub name: Impl::LocalName,
     pub lower_name: Impl::LocalName,
 }