3 files changed, 958 insertions, 0 deletions

diff --git a/vendor/syn/tests/common/eq.rs b/vendor/syn/tests/common/eq.rs
new file mode 100644
index 0000000..8ecbe46
--- /dev/null
+++ b/vendor/syn/tests/common/eq.rs
@@ -0,0 +1,879 @@
+#![allow(unused_macro_rules)]
+
+extern crate rustc_ast;
+extern crate rustc_data_structures;
+extern crate rustc_driver;
+extern crate rustc_span;
+extern crate thin_vec;
+
+use rustc_ast::ast::AngleBracketedArg;
+use rustc_ast::ast::AngleBracketedArgs;
+use rustc_ast::ast::AnonConst;
+use rustc_ast::ast::Arm;
+use rustc_ast::ast::AssocConstraint;
+use rustc_ast::ast::AssocConstraintKind;
+use rustc_ast::ast::AssocItemKind;
+use rustc_ast::ast::AttrArgs;
+use rustc_ast::ast::AttrArgsEq;
+use rustc_ast::ast::AttrId;
+use rustc_ast::ast::AttrItem;
+use rustc_ast::ast::AttrKind;
+use rustc_ast::ast::AttrStyle;
+use rustc_ast::ast::Attribute;
+use rustc_ast::ast::BareFnTy;
+use rustc_ast::ast::BinOpKind;
+use rustc_ast::ast::BindingAnnotation;
+use rustc_ast::ast::Block;
+use rustc_ast::ast::BlockCheckMode;
+use rustc_ast::ast::BorrowKind;
+use rustc_ast::ast::BoundConstness;
+use rustc_ast::ast::BoundPolarity;
+use rustc_ast::ast::ByRef;
+use rustc_ast::ast::CaptureBy;
+use rustc_ast::ast::Closure;
+use rustc_ast::ast::ClosureBinder;
+use rustc_ast::ast::Const;
+use rustc_ast::ast::ConstItem;
+use rustc_ast::ast::CoroutineKind;
+use rustc_ast::ast::Crate;
+use rustc_ast::ast::Defaultness;
+use rustc_ast::ast::DelimArgs;
+use rustc_ast::ast::EnumDef;
+use rustc_ast::ast::Expr;
+use rustc_ast::ast::ExprField;
+use rustc_ast::ast::ExprKind;
+use rustc_ast::ast::Extern;
+use rustc_ast::ast::FieldDef;
+use rustc_ast::ast::FloatTy;
+use rustc_ast::ast::Fn;
+use rustc_ast::ast::FnDecl;
+use rustc_ast::ast::FnHeader;
+use rustc_ast::ast::FnRetTy;
+use rustc_ast::ast::FnSig;
+use rustc_ast::ast::ForLoopKind;
+use rustc_ast::ast::ForeignItemKind;
+use rustc_ast::ast::ForeignMod;
+use rustc_ast::ast::FormatAlignment;
+use rustc_ast::ast::FormatArgPosition;
+use rustc_ast::ast::FormatArgPositionKind;
+use rustc_ast::ast::FormatArgs;
+use rustc_ast::ast::FormatArgsPiece;
+use rustc_ast::ast::FormatArgument;
+use rustc_ast::ast::FormatArgumentKind;
+use rustc_ast::ast::FormatArguments;
+use rustc_ast::ast::FormatCount;
+use rustc_ast::ast::FormatDebugHex;
+use rustc_ast::ast::FormatOptions;
+use rustc_ast::ast::FormatPlaceholder;
+use rustc_ast::ast::FormatSign;
+use rustc_ast::ast::FormatTrait;
+use rustc_ast::ast::GenBlockKind;
+use rustc_ast::ast::GenericArg;
+use rustc_ast::ast::GenericArgs;
+use rustc_ast::ast::GenericBound;
+use rustc_ast::ast::GenericParam;
+use rustc_ast::ast::GenericParamKind;
+use rustc_ast::ast::Generics;
+use rustc_ast::ast::Impl;
+use rustc_ast::ast::ImplPolarity;
+use rustc_ast::ast::Inline;
+use rustc_ast::ast::InlineAsm;
+use rustc_ast::ast::InlineAsmOperand;
+use rustc_ast::ast::InlineAsmOptions;
+use rustc_ast::ast::InlineAsmRegOrRegClass;
+use rustc_ast::ast::InlineAsmSym;
+use rustc_ast::ast::InlineAsmTemplatePiece;
+use rustc_ast::ast::IntTy;
+use rustc_ast::ast::IsAuto;
+use rustc_ast::ast::Item;
+use rustc_ast::ast::ItemKind;
+use rustc_ast::ast::Label;
+use rustc_ast::ast::Lifetime;
+use rustc_ast::ast::LitFloatType;
+use rustc_ast::ast::LitIntType;
+use rustc_ast::ast::LitKind;
+use rustc_ast::ast::Local;
+use rustc_ast::ast::LocalKind;
+use rustc_ast::ast::MacCall;
+use rustc_ast::ast::MacCallStmt;
+use rustc_ast::ast::MacStmtStyle;
+use rustc_ast::ast::MacroDef;
+use rustc_ast::ast::MetaItemLit;
+use rustc_ast::ast::MethodCall;
+use rustc_ast::ast::ModKind;
+use rustc_ast::ast::ModSpans;
+use rustc_ast::ast::Movability;
+use rustc_ast::ast::MutTy;
+use rustc_ast::ast::Mutability;
+use rustc_ast::ast::NodeId;
+use rustc_ast::ast::NormalAttr;
+use rustc_ast::ast::Param;
+use rustc_ast::ast::ParenthesizedArgs;
+use rustc_ast::ast::Pat;
+use rustc_ast::ast::PatField;
+use rustc_ast::ast::PatFieldsRest;
+use rustc_ast::ast::PatKind;
+use rustc_ast::ast::Path;
+use rustc_ast::ast::PathSegment;
+use rustc_ast::ast::PolyTraitRef;
+use rustc_ast::ast::QSelf;
+use rustc_ast::ast::RangeEnd;
+use rustc_ast::ast::RangeLimits;
+use rustc_ast::ast::RangeSyntax;
+use rustc_ast::ast::StaticItem;
+use rustc_ast::ast::Stmt;
+use rustc_ast::ast::StmtKind;
+use rustc_ast::ast::StrLit;
+use rustc_ast::ast::StrStyle;
+use rustc_ast::ast::StructExpr;
+use rustc_ast::ast::StructRest;
+use rustc_ast::ast::Term;
+use rustc_ast::ast::Trait;
+use rustc_ast::ast::TraitBoundModifiers;
+use rustc_ast::ast::TraitObjectSyntax;
+use rustc_ast::ast::TraitRef;
+use rustc_ast::ast::Ty;
+use rustc_ast::ast::TyAlias;
+use rustc_ast::ast::TyAliasWhereClause;
+use rustc_ast::ast::TyKind;
+use rustc_ast::ast::UintTy;
+use rustc_ast::ast::UnOp;
+use rustc_ast::ast::Unsafe;
+use rustc_ast::ast::UnsafeSource;
+use rustc_ast::ast::UseTree;
+use rustc_ast::ast::UseTreeKind;
+use rustc_ast::ast::Variant;
+use rustc_ast::ast::VariantData;
+use rustc_ast::ast::Visibility;
+use rustc_ast::ast::VisibilityKind;
+use rustc_ast::ast::WhereBoundPredicate;
+use rustc_ast::ast::WhereClause;
+use rustc_ast::ast::WhereEqPredicate;
+use rustc_ast::ast::WherePredicate;
+use rustc_ast::ast::WhereRegionPredicate;
+use rustc_ast::ptr::P;
+use rustc_ast::token::{self, CommentKind, Delimiter, Lit, Nonterminal, Token, TokenKind};
+use rustc_ast::tokenstream::{
+    AttrTokenStream, AttrTokenTree, AttributesData, DelimSpacing, DelimSpan, LazyAttrTokenStream,
+    Spacing, TokenStream, TokenTree,
+};
+use rustc_data_structures::sync::Lrc;
+use rustc_span::source_map::Spanned;
+use rustc_span::symbol::{sym, Ident};
+use rustc_span::{ErrorGuaranteed, Span, Symbol, SyntaxContext, DUMMY_SP};
+use std::collections::HashMap;
+use std::hash::{BuildHasher, Hash};
+use thin_vec::ThinVec;
+
+pub trait SpanlessEq {
+    fn eq(&self, other: &Self) -> bool;
+}
+
+impl<T: ?Sized + SpanlessEq> SpanlessEq for Box<T> {
+    fn eq(&self, other: &Self) -> bool {
+        SpanlessEq::eq(&**self, &**other)
+    }
+}
+
+impl<T: ?Sized + SpanlessEq> SpanlessEq for P<T> {
+    fn eq(&self, other: &Self) -> bool {
+        SpanlessEq::eq(&**self, &**other)
+    }
+}
+
+impl<T: ?Sized + SpanlessEq> SpanlessEq for Lrc<T> {
+    fn eq(&self, other: &Self) -> bool {
+        SpanlessEq::eq(&**self, &**other)
+    }
+}
+
+impl<T: SpanlessEq> SpanlessEq for Option<T> {
+    fn eq(&self, other: &Self) -> bool {
+        match (self, other) {
+            (None, None) => true,
+            (Some(this), Some(other)) => SpanlessEq::eq(this, other),
+            _ => false,
+        }
+    }
+}
+
+impl<T: SpanlessEq, E: SpanlessEq> SpanlessEq for Result<T, E> {
+    fn eq(&self, other: &Self) -> bool {
+        match (self, other) {
+            (Ok(this), Ok(other)) => SpanlessEq::eq(this, other),
+            (Err(this), Err(other)) => SpanlessEq::eq(this, other),
+            _ => false,
+        }
+    }
+}
+
+impl<T: SpanlessEq> SpanlessEq for [T] {
+    fn eq(&self, other: &Self) -> bool {
+        self.len() == other.len() && self.iter().zip(other).all(|(a, b)| SpanlessEq::eq(a, b))
+    }
+}
+
+impl<T: SpanlessEq> SpanlessEq for Vec<T> {
+    fn eq(&self, other: &Self) -> bool {
+        <[T] as SpanlessEq>::eq(self, other)
+    }
+}
+
+impl<T: SpanlessEq> SpanlessEq for ThinVec<T> {
+    fn eq(&self, other: &Self) -> bool {
+        self.len() == other.len()
+            && self
+                .iter()
+                .zip(other.iter())
+                .all(|(a, b)| SpanlessEq::eq(a, b))
+    }
+}
+
+impl<K: Eq + Hash, V: SpanlessEq, S: BuildHasher> SpanlessEq for HashMap<K, V, S> {
+    fn eq(&self, other: &Self) -> bool {
+        self.len() == other.len()
+            && self.iter().all(|(key, this_v)| {
+                other
+                    .get(key)
+                    .map_or(false, |other_v| SpanlessEq::eq(this_v, other_v))
+            })
+    }
+}
+
+impl<T: SpanlessEq> SpanlessEq for Spanned<T> {
+    fn eq(&self, other: &Self) -> bool {
+        SpanlessEq::eq(&self.node, &other.node)
+    }
+}
+
+impl<A: SpanlessEq, B: SpanlessEq> SpanlessEq for (A, B) {
+    fn eq(&self, other: &Self) -> bool {
+        SpanlessEq::eq(&self.0, &other.0) && SpanlessEq::eq(&self.1, &other.1)
+    }
+}
+
+impl<A: SpanlessEq, B: SpanlessEq, C: SpanlessEq> SpanlessEq for (A, B, C) {
+    fn eq(&self, other: &Self) -> bool {
+        SpanlessEq::eq(&self.0, &other.0)
+            && SpanlessEq::eq(&self.1, &other.1)
+            && SpanlessEq::eq(&self.2, &other.2)
+    }
+}
+
+macro_rules! spanless_eq_true {
+    ($name:ty) => {
+        impl SpanlessEq for $name {
+            fn eq(&self, _other: &Self) -> bool {
+                true
+            }
+        }
+    };
+}
+
+spanless_eq_true!(Span);
+spanless_eq_true!(DelimSpan);
+spanless_eq_true!(AttrId);
+spanless_eq_true!(NodeId);
+spanless_eq_true!(SyntaxContext);
+spanless_eq_true!(Spacing);
+
+macro_rules! spanless_eq_partial_eq {
+    ($name:ty) => {
+        impl SpanlessEq for $name {
+            fn eq(&self, other: &Self) -> bool {
+                PartialEq::eq(self, other)
+            }
+        }
+    };
+}
+
+spanless_eq_partial_eq!(bool);
+spanless_eq_partial_eq!(u8);
+spanless_eq_partial_eq!(u16);
+spanless_eq_partial_eq!(u32);
+spanless_eq_partial_eq!(u128);
+spanless_eq_partial_eq!(usize);
+spanless_eq_partial_eq!(char);
+spanless_eq_partial_eq!(String);
+spanless_eq_partial_eq!(Symbol);
+spanless_eq_partial_eq!(CommentKind);
+spanless_eq_partial_eq!(Delimiter);
+spanless_eq_partial_eq!(InlineAsmOptions);
+spanless_eq_partial_eq!(token::LitKind);
+spanless_eq_partial_eq!(ErrorGuaranteed);
+
+macro_rules! spanless_eq_struct {
+    {
+        $($name:ident)::+ $(<$param:ident>)?
+        $([$field:tt $this:ident $other:ident])*
+        $(![$ignore:tt])*;
+    } => {
+        impl $(<$param: SpanlessEq>)* SpanlessEq for $($name)::+ $(<$param>)* {
+            fn eq(&self, other: &Self) -> bool {
+                let $($name)::+ { $($field: $this,)* $($ignore: _,)* } = self;
+                let $($name)::+ { $($field: $other,)* $($ignore: _,)* } = other;
+                true $(&& SpanlessEq::eq($this, $other))*
+            }
+        }
+    };
+
+    {
+        $($name:ident)::+ $(<$param:ident>)?
+        $([$field:tt $this:ident $other:ident])*
+        $(![$ignore:tt])*;
+        !$next:tt
+        $($rest:tt)*
+    } => {
+        spanless_eq_struct! {
+            $($name)::+ $(<$param>)*
+            $([$field $this $other])*
+            $(![$ignore])*
+            ![$next];
+            $($rest)*
+        }
+    };
+
+    {
+        $($name:ident)::+ $(<$param:ident>)?
+        $([$field:tt $this:ident $other:ident])*
+        $(![$ignore:tt])*;
+        $next:tt
+        $($rest:tt)*
+    } => {
+        spanless_eq_struct! {
+            $($name)::+ $(<$param>)*
+            $([$field $this $other])*
+            [$next this other]
+            $(![$ignore])*;
+            $($rest)*
+        }
+    };
+}
+
+macro_rules! spanless_eq_enum {
+    {
+        $($name:ident)::+;
+        $([$($variant:ident)::+; $([$field:tt $this:ident $other:ident])* $(![$ignore:tt])*])*
+    } => {
+        impl SpanlessEq for $($name)::+ {
+            fn eq(&self, other: &Self) -> bool {
+                match self {
+                    $(
+                        $($variant)::+ { .. } => {}
+                    )*
+                }
+                #[allow(unreachable_patterns)]
+                match (self, other) {
+                    $(
+                        (
+                            $($variant)::+ { $($field: $this,)* $($ignore: _,)* },
+                            $($variant)::+ { $($field: $other,)* $($ignore: _,)* },
+                        ) => {
+                            true $(&& SpanlessEq::eq($this, $other))*
+                        }
+                    )*
+                    _ => false,
+                }
+            }
+        }
+    };
+
+    {
+        $($name:ident)::+;
+        $([$($variant:ident)::+; $($fields:tt)*])*
+        $next:ident [$([$($named:tt)*])* $(![$ignore:tt])*] (!$i:tt $($field:tt)*)
+        $($rest:tt)*
+    } => {
+        spanless_eq_enum! {
+            $($name)::+;
+            $([$($variant)::+; $($fields)*])*
+            $next [$([$($named)*])* $(![$ignore])* ![$i]] ($($field)*)
+            $($rest)*
+        }
+    };
+
+    {
+        $($name:ident)::+;
+        $([$($variant:ident)::+; $($fields:tt)*])*
+        $next:ident [$([$($named:tt)*])* $(![$ignore:tt])*] ($i:tt $($field:tt)*)
+        $($rest:tt)*
+    } => {
+        spanless_eq_enum! {
+            $($name)::+;
+            $([$($variant)::+; $($fields)*])*
+            $next [$([$($named)*])* [$i this other] $(![$ignore])*] ($($field)*)
+            $($rest)*
+        }
+    };
+
+    {
+        $($name:ident)::+;
+        $([$($variant:ident)::+; $($fields:tt)*])*
+        $next:ident [$($named:tt)*] ()
+        $($rest:tt)*
+    } => {
+        spanless_eq_enum! {
+            $($name)::+;
+            $([$($variant)::+; $($fields)*])*
+            [$($name)::+::$next; $($named)*]
+            $($rest)*
+        }
+    };
+
+    {
+        $($name:ident)::+;
+        $([$($variant:ident)::+; $($fields:tt)*])*
+        $next:ident ($($field:tt)*)
+        $($rest:tt)*
+    } => {
+        spanless_eq_enum! {
+            $($name)::+;
+            $([$($variant)::+; $($fields)*])*
+            $next [] ($($field)*)
+            $($rest)*
+        }
+    };
+
+    {
+        $($name:ident)::+;
+        $([$($variant:ident)::+; $($fields:tt)*])*
+        $next:ident
+        $($rest:tt)*
+    } => {
+        spanless_eq_enum! {
+            $($name)::+;
+            $([$($variant)::+; $($fields)*])*
+            [$($name)::+::$next;]
+            $($rest)*
+        }
+    };
+}
+
+spanless_eq_struct!(AngleBracketedArgs; span args);
+spanless_eq_struct!(AnonConst; id value);
+spanless_eq_struct!(Arm; attrs pat guard body span id is_placeholder);
+spanless_eq_struct!(AssocConstraint; id ident gen_args kind span);
+spanless_eq_struct!(AttrItem; path args tokens);
+spanless_eq_struct!(AttrTokenStream; 0);
+spanless_eq_struct!(Attribute; kind id style span);
+spanless_eq_struct!(AttributesData; attrs tokens);
+spanless_eq_struct!(BareFnTy; unsafety ext generic_params decl decl_span);
+spanless_eq_struct!(BindingAnnotation; 0 1);
+spanless_eq_struct!(Block; stmts id rules span tokens could_be_bare_literal);
+spanless_eq_struct!(Closure; binder capture_clause constness coroutine_kind movability fn_decl body !fn_decl_span !fn_arg_span);
+spanless_eq_struct!(ConstItem; defaultness generics ty expr);
+spanless_eq_struct!(Crate; attrs items spans id is_placeholder);
+spanless_eq_struct!(DelimArgs; dspan delim tokens);
+spanless_eq_struct!(DelimSpacing; open close);
+spanless_eq_struct!(EnumDef; variants);
+spanless_eq_struct!(Expr; id kind span attrs !tokens);
+spanless_eq_struct!(ExprField; attrs id span ident expr is_shorthand is_placeholder);
+spanless_eq_struct!(FieldDef; attrs id span vis ident ty is_placeholder);
+spanless_eq_struct!(Fn; defaultness generics sig body);
+spanless_eq_struct!(FnDecl; inputs output);
+spanless_eq_struct!(FnHeader; constness coroutine_kind unsafety ext);
+spanless_eq_struct!(FnSig; header decl span);
+spanless_eq_struct!(ForeignMod; unsafety abi items);
+spanless_eq_struct!(FormatArgPosition; index kind span);
+spanless_eq_struct!(FormatArgs; span template arguments);
+spanless_eq_struct!(FormatArgument; kind expr);
+spanless_eq_struct!(FormatOptions; width precision alignment fill sign alternate zero_pad debug_hex);
+spanless_eq_struct!(FormatPlaceholder; argument span format_trait format_options);
+spanless_eq_struct!(GenericParam; id ident attrs bounds is_placeholder kind !colon_span);
+spanless_eq_struct!(Generics; params where_clause span);
+spanless_eq_struct!(Impl; defaultness unsafety generics constness polarity of_trait self_ty items);
+spanless_eq_struct!(InlineAsm; template template_strs operands clobber_abis options line_spans);
+spanless_eq_struct!(InlineAsmSym; id qself path);
+spanless_eq_struct!(Item<K>; attrs id span vis ident kind !tokens);
+spanless_eq_struct!(Label; ident);
+spanless_eq_struct!(Lifetime; id ident);
+spanless_eq_struct!(Lit; kind symbol suffix);
+spanless_eq_struct!(Local; pat ty kind id span attrs !tokens);
+spanless_eq_struct!(MacCall; path args);
+spanless_eq_struct!(MacCallStmt; mac style attrs tokens);
+spanless_eq_struct!(MacroDef; body macro_rules);
+spanless_eq_struct!(MetaItemLit; symbol suffix kind span);
+spanless_eq_struct!(MethodCall; seg receiver args !span);
+spanless_eq_struct!(ModSpans; !inner_span !inject_use_span);
+spanless_eq_struct!(MutTy; ty mutbl);
+spanless_eq_struct!(NormalAttr; item tokens);
+spanless_eq_struct!(ParenthesizedArgs; span inputs inputs_span output);
+spanless_eq_struct!(Pat; id kind span tokens);
+spanless_eq_struct!(PatField; ident pat is_shorthand attrs id span is_placeholder);
+spanless_eq_struct!(Path; span segments tokens);
+spanless_eq_struct!(PathSegment; ident id args);
+spanless_eq_struct!(PolyTraitRef; bound_generic_params trait_ref span);
+spanless_eq_struct!(QSelf; ty path_span position);
+spanless_eq_struct!(StaticItem; ty mutability expr);
+spanless_eq_struct!(Stmt; id kind span);
+spanless_eq_struct!(StrLit; symbol suffix symbol_unescaped style span);
+spanless_eq_struct!(StructExpr; qself path fields rest);
+spanless_eq_struct!(Token; kind span);
+spanless_eq_struct!(Trait; unsafety is_auto generics bounds items);
+spanless_eq_struct!(TraitBoundModifiers; constness polarity);
+spanless_eq_struct!(TraitRef; path ref_id);
+spanless_eq_struct!(Ty; id kind span tokens);
+spanless_eq_struct!(TyAlias; defaultness generics where_clauses !where_predicates_split bounds ty);
+spanless_eq_struct!(TyAliasWhereClause; !0 1);
+spanless_eq_struct!(UseTree; prefix kind span);
+spanless_eq_struct!(Variant; attrs id span !vis ident data disr_expr is_placeholder);
+spanless_eq_struct!(Visibility; kind span tokens);
+spanless_eq_struct!(WhereBoundPredicate; span bound_generic_params bounded_ty bounds);
+spanless_eq_struct!(WhereClause; has_where_token predicates span);
+spanless_eq_struct!(WhereEqPredicate; span lhs_ty rhs_ty);
+spanless_eq_struct!(WhereRegionPredicate; span lifetime bounds);
+spanless_eq_enum!(AngleBracketedArg; Arg(0) Constraint(0));
+spanless_eq_enum!(AssocConstraintKind; Equality(term) Bound(bounds));
+spanless_eq_enum!(AssocItemKind; Const(0) Fn(0) Type(0) MacCall(0));
+spanless_eq_enum!(AttrArgs; Empty Delimited(0) Eq(0 1));
+spanless_eq_enum!(AttrArgsEq; Ast(0) Hir(0));
+spanless_eq_enum!(AttrStyle; Outer Inner);
+spanless_eq_enum!(AttrTokenTree; Token(0 1) Delimited(0 1 2 3) Attributes(0));
+spanless_eq_enum!(BinOpKind; Add Sub Mul Div Rem And Or BitXor BitAnd BitOr Shl Shr Eq Lt Le Ne Ge Gt);
+spanless_eq_enum!(BlockCheckMode; Default Unsafe(0));
+spanless_eq_enum!(BorrowKind; Ref Raw);
+spanless_eq_enum!(BoundConstness; Never Always(0) Maybe(0));
+spanless_eq_enum!(BoundPolarity; Positive Negative(0) Maybe(0));
+spanless_eq_enum!(ByRef; Yes No);
+spanless_eq_enum!(CaptureBy; Value(move_kw) Ref);
+spanless_eq_enum!(ClosureBinder; NotPresent For(span generic_params));
+spanless_eq_enum!(Const; Yes(0) No);
+spanless_eq_enum!(Defaultness; Default(0) Final);
+spanless_eq_enum!(Extern; None Implicit(0) Explicit(0 1));
+spanless_eq_enum!(FloatTy; F32 F64);
+spanless_eq_enum!(FnRetTy; Default(0) Ty(0));
+spanless_eq_enum!(ForLoopKind; For ForAwait);
+spanless_eq_enum!(ForeignItemKind; Static(0 1 2) Fn(0) TyAlias(0) MacCall(0));
+spanless_eq_enum!(FormatAlignment; Left Right Center);
+spanless_eq_enum!(FormatArgPositionKind; Implicit Number Named);
+spanless_eq_enum!(FormatArgsPiece; Literal(0) Placeholder(0));
+spanless_eq_enum!(FormatArgumentKind; Normal Named(0) Captured(0));
+spanless_eq_enum!(FormatCount; Literal(0) Argument(0));
+spanless_eq_enum!(FormatDebugHex; Lower Upper);
+spanless_eq_enum!(FormatSign; Plus Minus);
+spanless_eq_enum!(FormatTrait; Display Debug LowerExp UpperExp Octal Pointer Binary LowerHex UpperHex);
+spanless_eq_enum!(GenBlockKind; Async Gen AsyncGen);
+spanless_eq_enum!(GenericArg; Lifetime(0) Type(0) Const(0));
+spanless_eq_enum!(GenericArgs; AngleBracketed(0) Parenthesized(0));
+spanless_eq_enum!(GenericBound; Trait(0 1) Outlives(0));
+spanless_eq_enum!(GenericParamKind; Lifetime Type(default) Const(ty kw_span default));
+spanless_eq_enum!(ImplPolarity; Positive Negative(0));
+spanless_eq_enum!(Inline; Yes No);
+spanless_eq_enum!(InlineAsmRegOrRegClass; Reg(0) RegClass(0));
+spanless_eq_enum!(InlineAsmTemplatePiece; String(0) Placeholder(operand_idx modifier span));
+spanless_eq_enum!(IntTy; Isize I8 I16 I32 I64 I128);
+spanless_eq_enum!(IsAuto; Yes No);
+spanless_eq_enum!(LitFloatType; Suffixed(0) Unsuffixed);
+spanless_eq_enum!(LitIntType; Signed(0) Unsigned(0) Unsuffixed);
+spanless_eq_enum!(LocalKind; Decl Init(0) InitElse(0 1));
+spanless_eq_enum!(MacStmtStyle; Semicolon Braces NoBraces);
+spanless_eq_enum!(ModKind; Loaded(0 1 2) Unloaded);
+spanless_eq_enum!(Movability; Static Movable);
+spanless_eq_enum!(Mutability; Mut Not);
+spanless_eq_enum!(PatFieldsRest; Rest None);
+spanless_eq_enum!(RangeEnd; Included(0) Excluded);
+spanless_eq_enum!(RangeLimits; HalfOpen Closed);
+spanless_eq_enum!(StmtKind; Local(0) Item(0) Expr(0) Semi(0) Empty MacCall(0));
+spanless_eq_enum!(StrStyle; Cooked Raw(0));
+spanless_eq_enum!(StructRest; Base(0) Rest(0) None);
+spanless_eq_enum!(Term; Ty(0) Const(0));
+spanless_eq_enum!(TokenTree; Token(0 1) Delimited(0 1 2 3));
+spanless_eq_enum!(TraitObjectSyntax; Dyn DynStar None);
+spanless_eq_enum!(UintTy; Usize U8 U16 U32 U64 U128);
+spanless_eq_enum!(UnOp; Deref Not Neg);
+spanless_eq_enum!(Unsafe; Yes(0) No);
+spanless_eq_enum!(UnsafeSource; CompilerGenerated UserProvided);
+spanless_eq_enum!(UseTreeKind; Simple(0) Nested(0) Glob);
+spanless_eq_enum!(VariantData; Struct(fields recovered) Tuple(0 1) Unit(0));
+spanless_eq_enum!(VisibilityKind; Public Restricted(path id shorthand) Inherited);
+spanless_eq_enum!(WherePredicate; BoundPredicate(0) RegionPredicate(0) EqPredicate(0));
+spanless_eq_enum!(CoroutineKind; Async(span closure_id return_impl_trait_id)
+    Gen(span closure_id return_impl_trait_id)
+    AsyncGen(span closure_id return_impl_trait_id));
+spanless_eq_enum!(ExprKind; Array(0) ConstBlock(0) Call(0 1) MethodCall(0)
+    Tup(0) Binary(0 1 2) Unary(0 1) Lit(0) Cast(0 1) Type(0 1) Let(0 1 2 3)
+    If(0 1 2) While(0 1 2) ForLoop(pat iter body label kind) Loop(0 1 2)
+    Match(0 1) Closure(0) Block(0 1) Gen(0 1 2) Await(0 1) TryBlock(0)
+    Assign(0 1 2) AssignOp(0 1 2) Field(0 1) Index(0 1 2) Underscore
+    Range(0 1 2) Path(0 1) AddrOf(0 1 2) Break(0 1) Continue(0) Ret(0)
+    InlineAsm(0) OffsetOf(0 1) MacCall(0) Struct(0) Repeat(0 1) Paren(0) Try(0)
+    Yield(0) Yeet(0) Become(0) IncludedBytes(0) FormatArgs(0) Err);
+spanless_eq_enum!(InlineAsmOperand; In(reg expr) Out(reg late expr)
+    InOut(reg late expr) SplitInOut(reg late in_expr out_expr) Const(anon_const)
+    Sym(sym));
+spanless_eq_enum!(ItemKind; ExternCrate(0) Use(0) Static(0) Const(0) Fn(0)
+    Mod(0 1) ForeignMod(0) GlobalAsm(0) TyAlias(0) Enum(0 1) Struct(0 1)
+    Union(0 1) Trait(0) TraitAlias(0 1) Impl(0) MacCall(0) MacroDef(0));
+spanless_eq_enum!(LitKind; Str(0 1) ByteStr(0 1) CStr(0 1) Byte(0) Char(0)
+    Int(0 1) Float(0 1) Bool(0) Err);
+spanless_eq_enum!(PatKind; Wild Ident(0 1 2) Struct(0 1 2 3) TupleStruct(0 1 2)
+    Or(0) Path(0 1) Tuple(0) Box(0) Ref(0 1) Lit(0) Range(0 1 2) Slice(0) Rest
+    Never Paren(0) MacCall(0));
+spanless_eq_enum!(TyKind; Slice(0) Array(0 1) Ptr(0) Ref(0 1) BareFn(0) Never
+    Tup(0) AnonStruct(0) AnonUnion(0) Path(0 1) TraitObject(0 1) ImplTrait(0 1)
+    Paren(0) Typeof(0) Infer ImplicitSelf MacCall(0) Err CVarArgs);
+
+impl SpanlessEq for Ident {
+    fn eq(&self, other: &Self) -> bool {
+        self.as_str() == other.as_str()
+    }
+}
+
+impl SpanlessEq for RangeSyntax {
+    fn eq(&self, _other: &Self) -> bool {
+        match self {
+            RangeSyntax::DotDotDot | RangeSyntax::DotDotEq => true,
+        }
+    }
+}
+
+impl SpanlessEq for Param {
+    fn eq(&self, other: &Self) -> bool {
+        let Param {
+            attrs,
+            ty,
+            pat,
+            id,
+            span: _,
+            is_placeholder,
+        } = self;
+        let Param {
+            attrs: attrs2,
+            ty: ty2,
+            pat: pat2,
+            id: id2,
+            span: _,
+            is_placeholder: is_placeholder2,
+        } = other;
+        SpanlessEq::eq(id, id2)
+            && SpanlessEq::eq(is_placeholder, is_placeholder2)
+            && (matches!(ty.kind, TyKind::Err)
+                || matches!(ty2.kind, TyKind::Err)
+                || SpanlessEq::eq(attrs, attrs2)
+                    && SpanlessEq::eq(ty, ty2)
+                    && SpanlessEq::eq(pat, pat2))
+    }
+}
+
+impl SpanlessEq for TokenKind {
+    fn eq(&self, other: &Self) -> bool {
+        match (self, other) {
+            (TokenKind::Literal(this), TokenKind::Literal(other)) => SpanlessEq::eq(this, other),
+            (TokenKind::DotDotEq | TokenKind::DotDotDot, _) => match other {
+                TokenKind::DotDotEq | TokenKind::DotDotDot => true,
+                _ => false,
+            },
+            (TokenKind::Interpolated(this), TokenKind::Interpolated(other)) => {
+                let (this, this_span) = this.as_ref();
+                let (other, other_span) = other.as_ref();
+                SpanlessEq::eq(this_span, other_span)
+                    && match (this, other) {
+                        (Nonterminal::NtExpr(this), Nonterminal::NtExpr(other)) => {
+                            SpanlessEq::eq(this, other)
+                        }
+                        _ => this == other,
+                    }
+            }
+            _ => self == other,
+        }
+    }
+}
+
+impl SpanlessEq for TokenStream {
+    fn eq(&self, other: &Self) -> bool {
+        let mut this_trees = self.trees();
+        let mut other_trees = other.trees();
+        loop {
+            let this = match this_trees.next() {
+                None => return other_trees.next().is_none(),
+                Some(tree) => tree,
+            };
+            let other = match other_trees.next() {
+                None => return false,
+                Some(tree) => tree,
+            };
+            if SpanlessEq::eq(this, other) {
+                continue;
+            }
+            if let (TokenTree::Token(this, _), TokenTree::Token(other, _)) = (this, other) {
+                if match (&this.kind, &other.kind) {
+                    (TokenKind::Literal(this), TokenKind::Literal(other)) => {
+                        SpanlessEq::eq(this, other)
+                    }
+                    (TokenKind::DocComment(_kind, style, symbol), TokenKind::Pound) => {
+                        doc_comment(*style, *symbol, &mut other_trees)
+                    }
+                    (TokenKind::Pound, TokenKind::DocComment(_kind, style, symbol)) => {
+                        doc_comment(*style, *symbol, &mut this_trees)
+                    }
+                    _ => false,
+                } {
+                    continue;
+                }
+            }
+            return false;
+        }
+    }
+}
+
+fn doc_comment<'a>(
+    style: AttrStyle,
+    unescaped: Symbol,
+    trees: &mut impl Iterator<Item = &'a TokenTree>,
+) -> bool {
+    if match style {
+        AttrStyle::Outer => false,
+        AttrStyle::Inner => true,
+    } {
+        match trees.next() {
+            Some(TokenTree::Token(
+                Token {
+                    kind: TokenKind::Not,
+                    span: _,
+                },
+                _spacing,
+            )) => {}
+            _ => return false,
+        }
+    }
+    let stream = match trees.next() {
+        Some(TokenTree::Delimited(_span, _spacing, Delimiter::Bracket, stream)) => stream,
+        _ => return false,
+    };
+    let mut trees = stream.trees();
+    match trees.next() {
+        Some(TokenTree::Token(
+            Token {
+                kind: TokenKind::Ident(symbol, false),
+                span: _,
+            },
+            _spacing,
+        )) if *symbol == sym::doc => {}
+        _ => return false,
+    }
+    match trees.next() {
+        Some(TokenTree::Token(
+            Token {
+                kind: TokenKind::Eq,
+                span: _,
+            },
+            _spacing,
+        )) => {}
+        _ => return false,
+    }
+    match trees.next() {
+        Some(TokenTree::Token(token, _spacing)) => {
+            is_escaped_literal_token(token, unescaped) && trees.next().is_none()
+        }
+        _ => false,
+    }
+}
+
+fn is_escaped_literal_token(token: &Token, unescaped: Symbol) -> bool {
+    match token {
+        Token {
+            kind: TokenKind::Literal(lit),
+            span: _,
+        } => match MetaItemLit::from_token_lit(*lit, DUMMY_SP) {
+            Ok(lit) => is_escaped_literal_meta_item_lit(&lit, unescaped),
+            Err(_) => false,
+        },
+        Token {
+            kind: TokenKind::Interpolated(nonterminal),
+            span: _,
+        } => match &nonterminal.0 {
+            Nonterminal::NtExpr(expr) => match &expr.kind {
+                ExprKind::Lit(lit) => is_escaped_lit(lit, unescaped),
+                _ => false,
+            },
+            _ => false,
+        },
+        _ => false,
+    }
+}
+
+fn is_escaped_literal_attr_args(value: &AttrArgsEq, unescaped: Symbol) -> bool {
+    match value {
+        AttrArgsEq::Ast(expr) => match &expr.kind {
+            ExprKind::Lit(lit) => is_escaped_lit(lit, unescaped),
+            _ => false,
+        },
+        AttrArgsEq::Hir(lit) => is_escaped_literal_meta_item_lit(lit, unescaped),
+    }
+}
+
+fn is_escaped_literal_meta_item_lit(lit: &MetaItemLit, unescaped: Symbol) -> bool {
+    match lit {
+        MetaItemLit {
+            symbol: _,
+            suffix: None,
+            kind,
+            span: _,
+        } => is_escaped_lit_kind(kind, unescaped),
+        _ => false,
+    }
+}
+
+fn is_escaped_lit(lit: &Lit, unescaped: Symbol) -> bool {
+    match lit {
+        Lit {
+            kind: token::LitKind::Str,
+            symbol: _,
+            suffix: None,
+        } => match LitKind::from_token_lit(*lit) {
+            Ok(lit_kind) => is_escaped_lit_kind(&lit_kind, unescaped),
+            _ => false,
+        },
+        _ => false,
+    }
+}
+
+fn is_escaped_lit_kind(kind: &LitKind, unescaped: Symbol) -> bool {
+    match kind {
+        LitKind::Str(symbol, StrStyle::Cooked) => {
+            symbol.as_str().replace('\r', "") == unescaped.as_str().replace('\r', "")
+        }
+        _ => false,
+    }
+}
+
+impl SpanlessEq for LazyAttrTokenStream {
+    fn eq(&self, other: &Self) -> bool {
+        let this = self.to_attr_token_stream();
+        let other = other.to_attr_token_stream();
+        SpanlessEq::eq(&this, &other)
+    }
+}
+
+impl SpanlessEq for AttrKind {
+    fn eq(&self, other: &Self) -> bool {
+        match (self, other) {
+            (AttrKind::Normal(normal), AttrKind::Normal(normal2)) => {
+                SpanlessEq::eq(normal, normal2)
+            }
+            (AttrKind::DocComment(kind, symbol), AttrKind::DocComment(kind2, symbol2)) => {
+                SpanlessEq::eq(kind, kind2) && SpanlessEq::eq(symbol, symbol2)
+            }
+            (AttrKind::DocComment(kind, unescaped), AttrKind::Normal(normal2)) => {
+                match kind {
+                    CommentKind::Line | CommentKind::Block => {}
+                }
+                let path = Path::from_ident(Ident::with_dummy_span(sym::doc));
+                SpanlessEq::eq(&path, &normal2.item.path)
+                    && match &normal2.item.args {
+                        AttrArgs::Empty | AttrArgs::Delimited(_) => false,
+                        AttrArgs::Eq(_span, value) => {
+                            is_escaped_literal_attr_args(value, *unescaped)
+                        }
+                    }
+            }
+            (AttrKind::Normal(_), AttrKind::DocComment(..)) => SpanlessEq::eq(other, self),
+        }
+    }
+}
+
+impl SpanlessEq for FormatArguments {
+    fn eq(&self, other: &Self) -> bool {
+        SpanlessEq::eq(self.all_args(), other.all_args())
+    }
+}
diff --git a/vendor/syn/tests/common/mod.rs b/vendor/syn/tests/common/mod.rs
new file mode 100644
index 0000000..2156530
--- /dev/null
+++ b/vendor/syn/tests/common/mod.rs
@@ -0,0 +1,28 @@
+#![allow(dead_code)]
+#![allow(clippy::module_name_repetitions, clippy::shadow_unrelated)]
+
+use rayon::ThreadPoolBuilder;
+use std::env;
+
+pub mod eq;
+pub mod parse;
+
+/// Read the `ABORT_AFTER_FAILURE` environment variable, and parse it.
+pub fn abort_after() -> usize {
+    match env::var("ABORT_AFTER_FAILURE") {
+        Ok(s) => s.parse().expect("failed to parse ABORT_AFTER_FAILURE"),
+        Err(_) => usize::max_value(),
+    }
+}
+
+/// Configure Rayon threadpool.
+pub fn rayon_init() {
+    let stack_size = match env::var("RUST_MIN_STACK") {
+        Ok(s) => s.parse().expect("failed to parse RUST_MIN_STACK"),
+        Err(_) => 20 * 1024 * 1024,
+    };
+    ThreadPoolBuilder::new()
+        .stack_size(stack_size)
+        .build_global()
+        .unwrap();
+}
diff --git a/vendor/syn/tests/common/parse.rs b/vendor/syn/tests/common/parse.rs
new file mode 100644
index 0000000..73be101
--- /dev/null
+++ b/vendor/syn/tests/common/parse.rs
@@ -0,0 +1,51 @@
+extern crate rustc_ast;
+extern crate rustc_driver;
+extern crate rustc_expand;
+extern crate rustc_parse as parse;
+extern crate rustc_session;
+extern crate rustc_span;
+
+use rustc_ast::ast;
+use rustc_ast::ptr::P;
+use rustc_session::parse::ParseSess;
+use rustc_span::source_map::FilePathMapping;
+use rustc_span::FileName;
+use std::panic;
+
+pub fn librustc_expr(input: &str) -> Option<P<ast::Expr>> {
+    match panic::catch_unwind(|| {
+        let locale_resources = rustc_driver::DEFAULT_LOCALE_RESOURCES.to_vec();
+        let file_path_mapping = FilePathMapping::empty();
+        let sess = ParseSess::new(locale_resources, file_path_mapping);
+        let e = parse::new_parser_from_source_str(
+            &sess,
+            FileName::Custom("test_precedence".to_string()),
+            input.to_string(),
+        )
+        .parse_expr();
+        match e {
+            Ok(expr) => Some(expr),
+            Err(mut diagnostic) => {
+                diagnostic.emit();
+                None
+            }
+        }
+    }) {
+        Ok(Some(e)) => Some(e),
+        Ok(None) => None,
+        Err(_) => {
+            errorf!("librustc panicked\n");
+            None
+        }
+    }
+}
+
+pub fn syn_expr(input: &str) -> Option<syn::Expr> {
+    match syn::parse_str(input) {
+        Ok(e) => Some(e),
+        Err(msg) => {
+            errorf!("syn failed to parse\n{:?}\n", msg);
+            None
+        }
+    }
+}