1 extern crate rustc_ast;
2 extern crate rustc_data_structures;
3 extern crate rustc_span;
4 extern crate rustc_target;
5 
6 use rustc_ast::ast::{
7     AngleBracketedArg, AngleBracketedArgs, AnonConst, Arm, AssocItemKind, AssocTyConstraint,
8     AssocTyConstraintKind, Async, AttrId, AttrItem, AttrKind, AttrStyle, Attribute, BareFnTy,
9     BinOpKind, BindingMode, Block, BlockCheckMode, BorrowKind, CaptureBy, Const, Crate, CrateSugar,
10     Defaultness, EnumDef, Expr, ExprKind, Extern, Field, FieldPat, FloatTy, FnDecl, FnHeader,
11     FnRetTy, FnSig, ForeignItemKind, ForeignMod, GenericArg, GenericArgs, GenericBound,
12     GenericParam, GenericParamKind, Generics, GlobalAsm, ImplPolarity, InlineAsm, InlineAsmOperand,
13     InlineAsmOptions, InlineAsmRegOrRegClass, InlineAsmTemplatePiece, IntTy, IsAuto, Item,
14     ItemKind, Label, Lifetime, Lit, LitFloatType, LitIntType, LitKind, LlvmAsmDialect,
15     LlvmInlineAsm, LlvmInlineAsmOutput, Local, MacArgs, MacCall, MacCallStmt, MacDelimiter,
16     MacStmtStyle, MacroDef, Mod, Movability, MutTy, Mutability, NodeId, Param, ParenthesizedArgs,
17     Pat, PatKind, Path, PathSegment, PolyTraitRef, QSelf, RangeEnd, RangeLimits, RangeSyntax, Stmt,
18     StmtKind, StrLit, StrStyle, StructField, TraitBoundModifier, TraitObjectSyntax, TraitRef, Ty,
19     TyKind, UintTy, UnOp, Unsafe, UnsafeSource, UseTree, UseTreeKind, Variant, VariantData,
20     Visibility, VisibilityKind, WhereBoundPredicate, WhereClause, WhereEqPredicate, WherePredicate,
21     WhereRegionPredicate,
22 };
23 use rustc_ast::ptr::P;
24 use rustc_ast::token::{self, CommentKind, DelimToken, Token, TokenKind};
25 use rustc_ast::tokenstream::{DelimSpan, LazyTokenStream, TokenStream, TokenTree};
26 use rustc_data_structures::sync::Lrc;
27 use rustc_data_structures::thin_vec::ThinVec;
28 use rustc_span::source_map::Spanned;
29 use rustc_span::symbol::Ident;
30 use rustc_span::{Span, Symbol, SyntaxContext};
31 use std::mem;
32 
33 pub trait SpanlessEq {
eq(&self, other: &Self) -> bool34     fn eq(&self, other: &Self) -> bool;
35 }
36 
37 impl<T: SpanlessEq> SpanlessEq for P<T> {
eq(&self, other: &Self) -> bool38     fn eq(&self, other: &Self) -> bool {
39         SpanlessEq::eq(&**self, &**other)
40     }
41 }
42 
43 impl<T: ?Sized + SpanlessEq> SpanlessEq for Lrc<T> {
eq(&self, other: &Self) -> bool44     fn eq(&self, other: &Self) -> bool {
45         SpanlessEq::eq(&**self, &**other)
46     }
47 }
48 
49 impl<T: SpanlessEq> SpanlessEq for Option<T> {
eq(&self, other: &Self) -> bool50     fn eq(&self, other: &Self) -> bool {
51         match (self, other) {
52             (None, None) => true,
53             (Some(this), Some(other)) => SpanlessEq::eq(this, other),
54             _ => false,
55         }
56     }
57 }
58 
59 impl<T: SpanlessEq> SpanlessEq for [T] {
eq(&self, other: &Self) -> bool60     fn eq(&self, other: &Self) -> bool {
61         self.len() == other.len() && self.iter().zip(other).all(|(a, b)| SpanlessEq::eq(a, b))
62     }
63 }
64 
65 impl<T: SpanlessEq> SpanlessEq for Vec<T> {
eq(&self, other: &Self) -> bool66     fn eq(&self, other: &Self) -> bool {
67         <[T] as SpanlessEq>::eq(self, other)
68     }
69 }
70 
71 impl<T: SpanlessEq> SpanlessEq for ThinVec<T> {
eq(&self, other: &Self) -> bool72     fn eq(&self, other: &Self) -> bool {
73         self.len() == other.len()
74             && self
75                 .iter()
76                 .zip(other.iter())
77                 .all(|(a, b)| SpanlessEq::eq(a, b))
78     }
79 }
80 
81 impl<T: SpanlessEq> SpanlessEq for Spanned<T> {
eq(&self, other: &Self) -> bool82     fn eq(&self, other: &Self) -> bool {
83         SpanlessEq::eq(&self.node, &other.node)
84     }
85 }
86 
87 impl<A: SpanlessEq, B: SpanlessEq> SpanlessEq for (A, B) {
eq(&self, other: &Self) -> bool88     fn eq(&self, other: &Self) -> bool {
89         SpanlessEq::eq(&self.0, &other.0) && SpanlessEq::eq(&self.1, &other.1)
90     }
91 }
92 
93 macro_rules! spanless_eq_true {
94     ($name:ident) => {
95         impl SpanlessEq for $name {
96             fn eq(&self, _other: &Self) -> bool {
97                 true
98             }
99         }
100     };
101 }
102 
103 spanless_eq_true!(Span);
104 spanless_eq_true!(DelimSpan);
105 spanless_eq_true!(AttrId);
106 spanless_eq_true!(NodeId);
107 spanless_eq_true!(SyntaxContext);
108 
109 macro_rules! spanless_eq_partial_eq {
110     ($name:ident) => {
111         impl SpanlessEq for $name {
112             fn eq(&self, other: &Self) -> bool {
113                 PartialEq::eq(self, other)
114             }
115         }
116     };
117 }
118 
119 spanless_eq_partial_eq!(bool);
120 spanless_eq_partial_eq!(u8);
121 spanless_eq_partial_eq!(u16);
122 spanless_eq_partial_eq!(u128);
123 spanless_eq_partial_eq!(usize);
124 spanless_eq_partial_eq!(char);
125 spanless_eq_partial_eq!(String);
126 spanless_eq_partial_eq!(Symbol);
127 spanless_eq_partial_eq!(CommentKind);
128 spanless_eq_partial_eq!(DelimToken);
129 spanless_eq_partial_eq!(InlineAsmOptions);
130 
131 macro_rules! spanless_eq_struct {
132     {
133         $name:ident $(<$param:ident>)?;
134         $([$field:ident $other:ident])*
135         $(![$ignore:ident])*
136     } => {
137         impl $(<$param: SpanlessEq>)* SpanlessEq for $name $(<$param>)* {
138             fn eq(&self, other: &Self) -> bool {
139                 let $name { $($field,)* $($ignore: _,)* } = self;
140                 let $name { $($field: $other,)* $($ignore: _,)* } = other;
141                 $(SpanlessEq::eq($field, $other))&&*
142             }
143         }
144     };
145 
146     {
147         $name:ident $(<$param:ident>)?;
148         $([$field:ident $other:ident])*
149         $next:ident
150         $($rest:ident)*
151         $(!$ignore:ident)*
152     } => {
153         spanless_eq_struct! {
154             $name $(<$param>)*;
155             $([$field $other])*
156             [$next other]
157             $($rest)*
158             $(!$ignore)*
159         }
160     };
161 
162     {
163         $name:ident $(<$param:ident>)?;
164         $([$field:ident $other:ident])*
165         $(![$ignore:ident])*
166         !$next:ident
167         $(!$rest:ident)*
168     } => {
169         spanless_eq_struct! {
170             $name $(<$param>)*;
171             $([$field $other])*
172             $(![$ignore])*
173             ![$next]
174             $(!$rest)*
175         }
176     };
177 }
178 
179 macro_rules! spanless_eq_enum {
180     {
181         $name:ident;
182         $([$variant:ident $([$field:tt $this:ident $other:ident])*])*
183     } => {
184         impl SpanlessEq for $name {
185             fn eq(&self, other: &Self) -> bool {
186                 match self {
187                     $(
188                         $name::$variant { .. } => {}
189                     )*
190                 }
191                 #[allow(unreachable_patterns)]
192                 match (self, other) {
193                     $(
194                         (
195                             $name::$variant { $($field: $this),* },
196                             $name::$variant { $($field: $other),* },
197                         ) => {
198                             true $(&& SpanlessEq::eq($this, $other))*
199                         }
200                     )*
201                     _ => false,
202                 }
203             }
204         }
205     };
206 
207     {
208         $name:ident;
209         $([$variant:ident $($fields:tt)*])*
210         $next:ident [$($named:tt)*] ( $i:tt $($field:tt)* )
211         $($rest:tt)*
212     } => {
213         spanless_eq_enum! {
214             $name;
215             $([$variant $($fields)*])*
216             $next [$($named)* [$i this other]] ( $($field)* )
217             $($rest)*
218         }
219     };
220 
221     {
222         $name:ident;
223         $([$variant:ident $($fields:tt)*])*
224         $next:ident [$($named:tt)*] ()
225         $($rest:tt)*
226     } => {
227         spanless_eq_enum! {
228             $name;
229             $([$variant $($fields)*])*
230             [$next $($named)*]
231             $($rest)*
232         }
233     };
234 
235     {
236         $name:ident;
237         $([$variant:ident $($fields:tt)*])*
238         $next:ident ( $($field:tt)* )
239         $($rest:tt)*
240     } => {
241         spanless_eq_enum! {
242             $name;
243             $([$variant $($fields)*])*
244             $next [] ( $($field)* )
245             $($rest)*
246         }
247     };
248 
249     {
250         $name:ident;
251         $([$variant:ident $($fields:tt)*])*
252         $next:ident
253         $($rest:tt)*
254     } => {
255         spanless_eq_enum! {
256             $name;
257             $([$variant $($fields)*])*
258             [$next]
259             $($rest)*
260         }
261     };
262 }
263 
264 spanless_eq_struct!(AngleBracketedArgs; span args);
265 spanless_eq_struct!(AnonConst; id value);
266 spanless_eq_struct!(Arm; attrs pat guard body span id is_placeholder);
267 spanless_eq_struct!(AssocTyConstraint; id ident kind span);
268 spanless_eq_struct!(AttrItem; path args tokens);
269 spanless_eq_struct!(Attribute; kind id style span);
270 spanless_eq_struct!(BareFnTy; unsafety ext generic_params decl);
271 spanless_eq_struct!(Block; stmts id rules span tokens);
272 spanless_eq_struct!(Crate; module attrs span proc_macros);
273 spanless_eq_struct!(EnumDef; variants);
274 spanless_eq_struct!(Expr; id kind span attrs !tokens);
275 spanless_eq_struct!(Field; attrs id span ident expr is_shorthand is_placeholder);
276 spanless_eq_struct!(FieldPat; ident pat is_shorthand attrs id span is_placeholder);
277 spanless_eq_struct!(FnDecl; inputs output);
278 spanless_eq_struct!(FnHeader; constness asyncness unsafety ext);
279 spanless_eq_struct!(FnSig; header decl span);
280 spanless_eq_struct!(ForeignMod; unsafety abi items);
281 spanless_eq_struct!(GenericParam; id ident attrs bounds is_placeholder kind);
282 spanless_eq_struct!(Generics; params where_clause span);
283 spanless_eq_struct!(GlobalAsm; asm);
284 spanless_eq_struct!(InlineAsm; template operands options line_spans);
285 spanless_eq_struct!(Item<K>; attrs id span vis ident kind !tokens);
286 spanless_eq_struct!(Label; ident);
287 spanless_eq_struct!(Lifetime; id ident);
288 spanless_eq_struct!(Lit; token kind span);
289 spanless_eq_struct!(LlvmInlineAsm; asm asm_str_style outputs inputs clobbers volatile alignstack dialect);
290 spanless_eq_struct!(LlvmInlineAsmOutput; constraint expr is_rw is_indirect);
291 spanless_eq_struct!(Local; pat ty init id span attrs);
292 spanless_eq_struct!(MacCall; path args prior_type_ascription);
293 spanless_eq_struct!(MacCallStmt; mac style attrs);
294 spanless_eq_struct!(MacroDef; body macro_rules);
295 spanless_eq_struct!(Mod; inner unsafety items inline);
296 spanless_eq_struct!(MutTy; ty mutbl);
297 spanless_eq_struct!(Param; attrs ty pat id span is_placeholder);
298 spanless_eq_struct!(ParenthesizedArgs; span inputs output);
299 spanless_eq_struct!(Pat; id kind span tokens);
300 spanless_eq_struct!(Path; span segments tokens);
301 spanless_eq_struct!(PathSegment; ident id args);
302 spanless_eq_struct!(PolyTraitRef; bound_generic_params trait_ref span);
303 spanless_eq_struct!(QSelf; ty path_span position);
304 spanless_eq_struct!(Stmt; id kind span tokens);
305 spanless_eq_struct!(StrLit; style symbol suffix span symbol_unescaped);
306 spanless_eq_struct!(StructField; attrs id span vis ident ty is_placeholder);
307 spanless_eq_struct!(Token; kind span);
308 spanless_eq_struct!(TraitRef; path ref_id);
309 spanless_eq_struct!(Ty; id kind span tokens);
310 spanless_eq_struct!(UseTree; prefix kind span);
311 spanless_eq_struct!(Variant; attrs id span vis ident data disr_expr is_placeholder);
312 spanless_eq_struct!(Visibility; kind span tokens);
313 spanless_eq_struct!(WhereBoundPredicate; span bound_generic_params bounded_ty bounds);
314 spanless_eq_struct!(WhereClause; has_where_token predicates span);
315 spanless_eq_struct!(WhereEqPredicate; id span lhs_ty rhs_ty);
316 spanless_eq_struct!(WhereRegionPredicate; span lifetime bounds);
317 spanless_eq_enum!(AngleBracketedArg; Arg(0) Constraint(0));
318 spanless_eq_enum!(AssocItemKind; Const(0 1 2) Fn(0 1 2 3) TyAlias(0 1 2 3) MacCall(0));
319 spanless_eq_enum!(AssocTyConstraintKind; Equality(ty) Bound(bounds));
320 spanless_eq_enum!(Async; Yes(span closure_id return_impl_trait_id) No);
321 spanless_eq_enum!(AttrKind; Normal(0) DocComment(0 1));
322 spanless_eq_enum!(AttrStyle; Outer Inner);
323 spanless_eq_enum!(BinOpKind; Add Sub Mul Div Rem And Or BitXor BitAnd BitOr Shl Shr Eq Lt Le Ne Ge Gt);
324 spanless_eq_enum!(BindingMode; ByRef(0) ByValue(0));
325 spanless_eq_enum!(BlockCheckMode; Default Unsafe(0));
326 spanless_eq_enum!(BorrowKind; Ref Raw);
327 spanless_eq_enum!(CaptureBy; Value Ref);
328 spanless_eq_enum!(Const; Yes(0) No);
329 spanless_eq_enum!(CrateSugar; PubCrate JustCrate);
330 spanless_eq_enum!(Defaultness; Default(0) Final);
331 spanless_eq_enum!(Extern; None Implicit Explicit(0));
332 spanless_eq_enum!(FloatTy; F32 F64);
333 spanless_eq_enum!(FnRetTy; Default(0) Ty(0));
334 spanless_eq_enum!(ForeignItemKind; Static(0 1 2) Fn(0 1 2 3) TyAlias(0 1 2 3) MacCall(0));
335 spanless_eq_enum!(GenericArg; Lifetime(0) Type(0) Const(0));
336 spanless_eq_enum!(GenericArgs; AngleBracketed(0) Parenthesized(0));
337 spanless_eq_enum!(GenericBound; Trait(0 1) Outlives(0));
338 spanless_eq_enum!(GenericParamKind; Lifetime Type(default) Const(ty kw_span));
339 spanless_eq_enum!(ImplPolarity; Positive Negative(0));
340 spanless_eq_enum!(InlineAsmRegOrRegClass; Reg(0) RegClass(0));
341 spanless_eq_enum!(InlineAsmTemplatePiece; String(0) Placeholder(operand_idx modifier span));
342 spanless_eq_enum!(IntTy; Isize I8 I16 I32 I64 I128);
343 spanless_eq_enum!(IsAuto; Yes No);
344 spanless_eq_enum!(LitFloatType; Suffixed(0) Unsuffixed);
345 spanless_eq_enum!(LitIntType; Signed(0) Unsigned(0) Unsuffixed);
346 spanless_eq_enum!(LlvmAsmDialect; Att Intel);
347 spanless_eq_enum!(MacArgs; Empty Delimited(0 1 2) Eq(0 1));
348 spanless_eq_enum!(MacDelimiter; Parenthesis Bracket Brace);
349 spanless_eq_enum!(MacStmtStyle; Semicolon Braces NoBraces);
350 spanless_eq_enum!(Movability; Static Movable);
351 spanless_eq_enum!(Mutability; Mut Not);
352 spanless_eq_enum!(RangeEnd; Included(0) Excluded);
353 spanless_eq_enum!(RangeLimits; HalfOpen Closed);
354 spanless_eq_enum!(StmtKind; Local(0) Item(0) Expr(0) Semi(0) Empty MacCall(0));
355 spanless_eq_enum!(StrStyle; Cooked Raw(0));
356 spanless_eq_enum!(TokenTree; Token(0) Delimited(0 1 2));
357 spanless_eq_enum!(TraitBoundModifier; None Maybe MaybeConst MaybeConstMaybe);
358 spanless_eq_enum!(TraitObjectSyntax; Dyn None);
359 spanless_eq_enum!(UintTy; Usize U8 U16 U32 U64 U128);
360 spanless_eq_enum!(UnOp; Deref Not Neg);
361 spanless_eq_enum!(Unsafe; Yes(0) No);
362 spanless_eq_enum!(UnsafeSource; CompilerGenerated UserProvided);
363 spanless_eq_enum!(UseTreeKind; Simple(0 1 2) Nested(0) Glob);
364 spanless_eq_enum!(VariantData; Struct(0 1) Tuple(0 1) Unit(0));
365 spanless_eq_enum!(VisibilityKind; Public Crate(0) Restricted(path id) Inherited);
366 spanless_eq_enum!(WherePredicate; BoundPredicate(0) RegionPredicate(0) EqPredicate(0));
367 spanless_eq_enum!(ExprKind; Box(0) Array(0) ConstBlock(0) Call(0 1)
368     MethodCall(0 1 2) Tup(0) Binary(0 1 2) Unary(0 1) Lit(0) Cast(0 1) Type(0 1)
369     Let(0 1) If(0 1 2) While(0 1 2) ForLoop(0 1 2 3) Loop(0 1) Match(0 1)
370     Closure(0 1 2 3 4 5) Block(0 1) Async(0 1 2) Await(0) TryBlock(0)
371     Assign(0 1 2) AssignOp(0 1 2) Field(0 1) Index(0 1) Range(0 1 2) Path(0 1)
372     AddrOf(0 1 2) Break(0 1) Continue(0) Ret(0) InlineAsm(0) LlvmInlineAsm(0)
373     MacCall(0) Struct(0 1 2) Repeat(0 1) Paren(0) Try(0) Yield(0) Err);
374 spanless_eq_enum!(InlineAsmOperand; In(reg expr) Out(reg late expr)
375     InOut(reg late expr) SplitInOut(reg late in_expr out_expr) Const(expr)
376     Sym(expr));
377 spanless_eq_enum!(ItemKind; ExternCrate(0) Use(0) Static(0 1 2) Const(0 1 2)
378     Fn(0 1 2 3) Mod(0) ForeignMod(0) GlobalAsm(0) TyAlias(0 1 2 3) Enum(0 1)
379     Struct(0 1) Union(0 1) Trait(0 1 2 3 4) TraitAlias(0 1)
380     Impl(unsafety polarity defaultness constness generics of_trait self_ty items)
381     MacCall(0) MacroDef(0));
382 spanless_eq_enum!(LitKind; Str(0 1) ByteStr(0) Byte(0) Char(0) Int(0 1)
383     Float(0 1) Bool(0) Err(0));
384 spanless_eq_enum!(PatKind; Wild Ident(0 1 2) Struct(0 1 2) TupleStruct(0 1)
385     Or(0) Path(0 1) Tuple(0) Box(0) Ref(0 1) Lit(0) Range(0 1 2) Slice(0) Rest
386     Paren(0) MacCall(0));
387 spanless_eq_enum!(TyKind; Slice(0) Array(0 1) Ptr(0) Rptr(0 1) BareFn(0) Never
388     Tup(0) Path(0 1) TraitObject(0 1) ImplTrait(0 1) Paren(0) Typeof(0) Infer
389     ImplicitSelf MacCall(0) Err CVarArgs);
390 
391 impl SpanlessEq for Ident {
eq(&self, other: &Self) -> bool392     fn eq(&self, other: &Self) -> bool {
393         self.as_str() == other.as_str()
394     }
395 }
396 
397 // Give up on comparing literals inside of macros because there are so many
398 // equivalent representations of the same literal; they are tested elsewhere
399 impl SpanlessEq for token::Lit {
eq(&self, other: &Self) -> bool400     fn eq(&self, other: &Self) -> bool {
401         mem::discriminant(self) == mem::discriminant(other)
402     }
403 }
404 
405 impl SpanlessEq for RangeSyntax {
eq(&self, _other: &Self) -> bool406     fn eq(&self, _other: &Self) -> bool {
407         match self {
408             RangeSyntax::DotDotDot | RangeSyntax::DotDotEq => true,
409         }
410     }
411 }
412 
413 impl SpanlessEq for TokenKind {
eq(&self, other: &Self) -> bool414     fn eq(&self, other: &Self) -> bool {
415         match (self, other) {
416             (TokenKind::Literal(this), TokenKind::Literal(other)) => SpanlessEq::eq(this, other),
417             (TokenKind::DotDotEq, _) | (TokenKind::DotDotDot, _) => match other {
418                 TokenKind::DotDotEq | TokenKind::DotDotDot => true,
419                 _ => false,
420             },
421             _ => self == other,
422         }
423     }
424 }
425 
426 impl SpanlessEq for TokenStream {
eq(&self, other: &Self) -> bool427     fn eq(&self, other: &Self) -> bool {
428         let mut this = self.clone().into_trees();
429         let mut other = other.clone().into_trees();
430         loop {
431             let this = match this.next() {
432                 None => return other.next().is_none(),
433                 Some(val) => val,
434             };
435             let other = match other.next() {
436                 None => return false,
437                 Some(val) => val,
438             };
439             if !SpanlessEq::eq(&this, &other) {
440                 return false;
441             }
442         }
443     }
444 }
445 
446 impl SpanlessEq for LazyTokenStream {
eq(&self, other: &Self) -> bool447     fn eq(&self, other: &Self) -> bool {
448         let this = self.into_token_stream();
449         let other = other.into_token_stream();
450         SpanlessEq::eq(&this, &other)
451     }
452 }
453