1 #![deny(rustc::untranslatable_diagnostic)]
4 ArgumentNotAttributes
, AttrNoArguments
, AttributeMetaItem
, AttributeSingleWord
,
5 AttributesWrongForm
, CannotBeNameOfMacro
, ExpectedCommaInList
, HelperAttributeNameInvalid
,
6 MacroBodyStability
, MacroConstStability
, NotAMetaItem
, OnlyOneArgument
, OnlyOneWord
,
7 ResolveRelativePath
, TakesNoArguments
,
9 use crate::expand
::{self, AstFragment, Invocation}
;
10 use crate::module
::DirOwnership
;
12 use rustc_ast
::attr
::MarkedAttrs
;
13 use rustc_ast
::ptr
::P
;
14 use rustc_ast
::token
::{self, Nonterminal}
;
15 use rustc_ast
::tokenstream
::TokenStream
;
16 use rustc_ast
::visit
::{AssocCtxt, Visitor}
;
17 use rustc_ast
::{self as ast, AttrVec, Attribute, HasAttrs, Item, NodeId, PatKind}
;
18 use rustc_attr
::{self as attr, Deprecation, Stability}
;
19 use rustc_data_structures
::fx
::{FxHashSet, FxIndexMap}
;
20 use rustc_data_structures
::sync
::{self, Lrc}
;
22 Applicability
, DiagnosticBuilder
, ErrorGuaranteed
, IntoDiagnostic
, MultiSpan
, PResult
,
24 use rustc_lint_defs
::builtin
::PROC_MACRO_BACK_COMPAT
;
25 use rustc_lint_defs
::{BufferedEarlyLint, BuiltinLintDiagnostics}
;
26 use rustc_parse
::{self, parser, MACRO_ARGUMENTS}
;
27 use rustc_session
::errors
::report_lit_error
;
28 use rustc_session
::{parse::ParseSess, Limit, Session}
;
29 use rustc_span
::def_id
::{CrateNum, DefId, LocalDefId}
;
30 use rustc_span
::edition
::Edition
;
31 use rustc_span
::hygiene
::{AstPass, ExpnData, ExpnKind, LocalExpnId}
;
32 use rustc_span
::source_map
::SourceMap
;
33 use rustc_span
::symbol
::{kw, sym, Ident, Symbol}
;
34 use rustc_span
::{BytePos, FileName, Span, DUMMY_SP}
;
35 use smallvec
::{smallvec, SmallVec}
;
38 use std
::path
::{Path, PathBuf}
;
41 pub(crate) use rustc_span
::hygiene
::MacroKind
;
43 // When adding new variants, make sure to
44 // adjust the `visit_*` / `flat_map_*` calls in `InvocationCollector`
45 // to use `assign_id!`
46 #[derive(Debug, Clone)]
47 pub enum Annotatable
{
49 TraitItem(P
<ast
::AssocItem
>),
50 ImplItem(P
<ast
::AssocItem
>),
51 ForeignItem(P
<ast
::ForeignItem
>),
55 ExprField(ast
::ExprField
),
56 PatField(ast
::PatField
),
57 GenericParam(ast
::GenericParam
),
59 FieldDef(ast
::FieldDef
),
60 Variant(ast
::Variant
),
65 pub fn span(&self) -> Span
{
67 Annotatable
::Item(item
) => item
.span
,
68 Annotatable
::TraitItem(trait_item
) => trait_item
.span
,
69 Annotatable
::ImplItem(impl_item
) => impl_item
.span
,
70 Annotatable
::ForeignItem(foreign_item
) => foreign_item
.span
,
71 Annotatable
::Stmt(stmt
) => stmt
.span
,
72 Annotatable
::Expr(expr
) => expr
.span
,
73 Annotatable
::Arm(arm
) => arm
.span
,
74 Annotatable
::ExprField(field
) => field
.span
,
75 Annotatable
::PatField(fp
) => fp
.pat
.span
,
76 Annotatable
::GenericParam(gp
) => gp
.ident
.span
,
77 Annotatable
::Param(p
) => p
.span
,
78 Annotatable
::FieldDef(sf
) => sf
.span
,
79 Annotatable
::Variant(v
) => v
.span
,
80 Annotatable
::Crate(c
) => c
.spans
.inner_span
,
84 pub fn visit_attrs(&mut self, f
: impl FnOnce(&mut AttrVec
)) {
86 Annotatable
::Item(item
) => item
.visit_attrs(f
),
87 Annotatable
::TraitItem(trait_item
) => trait_item
.visit_attrs(f
),
88 Annotatable
::ImplItem(impl_item
) => impl_item
.visit_attrs(f
),
89 Annotatable
::ForeignItem(foreign_item
) => foreign_item
.visit_attrs(f
),
90 Annotatable
::Stmt(stmt
) => stmt
.visit_attrs(f
),
91 Annotatable
::Expr(expr
) => expr
.visit_attrs(f
),
92 Annotatable
::Arm(arm
) => arm
.visit_attrs(f
),
93 Annotatable
::ExprField(field
) => field
.visit_attrs(f
),
94 Annotatable
::PatField(fp
) => fp
.visit_attrs(f
),
95 Annotatable
::GenericParam(gp
) => gp
.visit_attrs(f
),
96 Annotatable
::Param(p
) => p
.visit_attrs(f
),
97 Annotatable
::FieldDef(sf
) => sf
.visit_attrs(f
),
98 Annotatable
::Variant(v
) => v
.visit_attrs(f
),
99 Annotatable
::Crate(c
) => c
.visit_attrs(f
),
103 pub fn visit_with
<'a
, V
: Visitor
<'a
>>(&'a
self, visitor
: &mut V
) {
105 Annotatable
::Item(item
) => visitor
.visit_item(item
),
106 Annotatable
::TraitItem(item
) => visitor
.visit_assoc_item(item
, AssocCtxt
::Trait
),
107 Annotatable
::ImplItem(item
) => visitor
.visit_assoc_item(item
, AssocCtxt
::Impl
),
108 Annotatable
::ForeignItem(foreign_item
) => visitor
.visit_foreign_item(foreign_item
),
109 Annotatable
::Stmt(stmt
) => visitor
.visit_stmt(stmt
),
110 Annotatable
::Expr(expr
) => visitor
.visit_expr(expr
),
111 Annotatable
::Arm(arm
) => visitor
.visit_arm(arm
),
112 Annotatable
::ExprField(field
) => visitor
.visit_expr_field(field
),
113 Annotatable
::PatField(fp
) => visitor
.visit_pat_field(fp
),
114 Annotatable
::GenericParam(gp
) => visitor
.visit_generic_param(gp
),
115 Annotatable
::Param(p
) => visitor
.visit_param(p
),
116 Annotatable
::FieldDef(sf
) => visitor
.visit_field_def(sf
),
117 Annotatable
::Variant(v
) => visitor
.visit_variant(v
),
118 Annotatable
::Crate(c
) => visitor
.visit_crate(c
),
122 pub fn to_tokens(&self) -> TokenStream
{
124 Annotatable
::Item(node
) => TokenStream
::from_ast(node
),
125 Annotatable
::TraitItem(node
) | Annotatable
::ImplItem(node
) => {
126 TokenStream
::from_ast(node
)
128 Annotatable
::ForeignItem(node
) => TokenStream
::from_ast(node
),
129 Annotatable
::Stmt(node
) => {
130 assert
!(!matches
!(node
.kind
, ast
::StmtKind
::Empty
));
131 TokenStream
::from_ast(node
)
133 Annotatable
::Expr(node
) => TokenStream
::from_ast(node
),
135 | Annotatable
::ExprField(..)
136 | Annotatable
::PatField(..)
137 | Annotatable
::GenericParam(..)
138 | Annotatable
::Param(..)
139 | Annotatable
::FieldDef(..)
140 | Annotatable
::Variant(..)
141 | Annotatable
::Crate(..) => panic
!("unexpected annotatable"),
145 pub fn expect_item(self) -> P
<ast
::Item
> {
147 Annotatable
::Item(i
) => i
,
148 _
=> panic
!("expected Item"),
152 pub fn expect_trait_item(self) -> P
<ast
::AssocItem
> {
154 Annotatable
::TraitItem(i
) => i
,
155 _
=> panic
!("expected Item"),
159 pub fn expect_impl_item(self) -> P
<ast
::AssocItem
> {
161 Annotatable
::ImplItem(i
) => i
,
162 _
=> panic
!("expected Item"),
166 pub fn expect_foreign_item(self) -> P
<ast
::ForeignItem
> {
168 Annotatable
::ForeignItem(i
) => i
,
169 _
=> panic
!("expected foreign item"),
173 pub fn expect_stmt(self) -> ast
::Stmt
{
175 Annotatable
::Stmt(stmt
) => stmt
.into_inner(),
176 _
=> panic
!("expected statement"),
180 pub fn expect_expr(self) -> P
<ast
::Expr
> {
182 Annotatable
::Expr(expr
) => expr
,
183 _
=> panic
!("expected expression"),
187 pub fn expect_arm(self) -> ast
::Arm
{
189 Annotatable
::Arm(arm
) => arm
,
190 _
=> panic
!("expected match arm"),
194 pub fn expect_expr_field(self) -> ast
::ExprField
{
196 Annotatable
::ExprField(field
) => field
,
197 _
=> panic
!("expected field"),
201 pub fn expect_pat_field(self) -> ast
::PatField
{
203 Annotatable
::PatField(fp
) => fp
,
204 _
=> panic
!("expected field pattern"),
208 pub fn expect_generic_param(self) -> ast
::GenericParam
{
210 Annotatable
::GenericParam(gp
) => gp
,
211 _
=> panic
!("expected generic parameter"),
215 pub fn expect_param(self) -> ast
::Param
{
217 Annotatable
::Param(param
) => param
,
218 _
=> panic
!("expected parameter"),
222 pub fn expect_field_def(self) -> ast
::FieldDef
{
224 Annotatable
::FieldDef(sf
) => sf
,
225 _
=> panic
!("expected struct field"),
229 pub fn expect_variant(self) -> ast
::Variant
{
231 Annotatable
::Variant(v
) => v
,
232 _
=> panic
!("expected variant"),
236 pub fn expect_crate(self) -> ast
::Crate
{
238 Annotatable
::Crate(krate
) => krate
,
239 _
=> panic
!("expected krate"),
244 /// Result of an expansion that may need to be retried.
245 /// Consider using this for non-`MultiItemModifier` expanders as well.
246 pub enum ExpandResult
<T
, U
> {
247 /// Expansion produced a result (possibly dummy).
249 /// Expansion could not produce a result and needs to be retried.
253 pub trait MultiItemModifier
{
254 /// `meta_item` is the attribute, and `item` is the item being modified.
257 ecx
: &mut ExtCtxt
<'_
>,
259 meta_item
: &ast
::MetaItem
,
261 is_derive_const
: bool
,
262 ) -> ExpandResult
<Vec
<Annotatable
>, Annotatable
>;
265 impl<F
> MultiItemModifier
for F
267 F
: Fn(&mut ExtCtxt
<'_
>, Span
, &ast
::MetaItem
, Annotatable
) -> Vec
<Annotatable
>,
271 ecx
: &mut ExtCtxt
<'_
>,
273 meta_item
: &ast
::MetaItem
,
275 _is_derive_const
: bool
,
276 ) -> ExpandResult
<Vec
<Annotatable
>, Annotatable
> {
277 ExpandResult
::Ready(self(ecx
, span
, meta_item
, item
))
281 pub trait BangProcMacro
{
284 ecx
: &'cx
mut ExtCtxt
<'_
>,
287 ) -> Result
<TokenStream
, ErrorGuaranteed
>;
290 impl<F
> BangProcMacro
for F
292 F
: Fn(TokenStream
) -> TokenStream
,
296 _ecx
: &'cx
mut ExtCtxt
<'_
>,
299 ) -> Result
<TokenStream
, ErrorGuaranteed
> {
300 // FIXME setup implicit context in TLS before calling self.
305 pub trait AttrProcMacro
{
308 ecx
: &'cx
mut ExtCtxt
<'_
>,
310 annotation
: TokenStream
,
311 annotated
: TokenStream
,
312 ) -> Result
<TokenStream
, ErrorGuaranteed
>;
315 impl<F
> AttrProcMacro
for F
317 F
: Fn(TokenStream
, TokenStream
) -> TokenStream
,
321 _ecx
: &'cx
mut ExtCtxt
<'_
>,
323 annotation
: TokenStream
,
324 annotated
: TokenStream
,
325 ) -> Result
<TokenStream
, ErrorGuaranteed
> {
326 // FIXME setup implicit context in TLS before calling self.
327 Ok(self(annotation
, annotated
))
331 /// Represents a thing that maps token trees to Macro Results
332 pub trait TTMacroExpander
{
335 ecx
: &'cx
mut ExtCtxt
<'_
>,
338 ) -> Box
<dyn MacResult
+ 'cx
>;
341 pub type MacroExpanderFn
=
342 for<'cx
> fn(&'cx
mut ExtCtxt
<'_
>, Span
, TokenStream
) -> Box
<dyn MacResult
+ 'cx
>;
344 impl<F
> TTMacroExpander
for F
346 F
: for<'cx
> Fn(&'cx
mut ExtCtxt
<'_
>, Span
, TokenStream
) -> Box
<dyn MacResult
+ 'cx
>,
350 ecx
: &'cx
mut ExtCtxt
<'_
>,
353 ) -> Box
<dyn MacResult
+ 'cx
> {
354 self(ecx
, span
, input
)
358 // Use a macro because forwarding to a simple function has type system issues
359 macro_rules
! make_stmts_default
{
361 $me
.make_expr().map(|e
| {
362 smallvec
![ast
::Stmt
{
363 id
: ast
::DUMMY_NODE_ID
,
365 kind
: ast
::StmtKind
::Expr(e
),
371 /// The result of a macro expansion. The return values of the various
372 /// methods are spliced into the AST at the callsite of the macro.
373 pub trait MacResult
{
374 /// Creates an expression.
375 fn make_expr(self: Box
<Self>) -> Option
<P
<ast
::Expr
>> {
379 /// Creates zero or more items.
380 fn make_items(self: Box
<Self>) -> Option
<SmallVec
<[P
<ast
::Item
>; 1]>> {
384 /// Creates zero or more impl items.
385 fn make_impl_items(self: Box
<Self>) -> Option
<SmallVec
<[P
<ast
::AssocItem
>; 1]>> {
389 /// Creates zero or more trait items.
390 fn make_trait_items(self: Box
<Self>) -> Option
<SmallVec
<[P
<ast
::AssocItem
>; 1]>> {
394 /// Creates zero or more items in an `extern {}` block
395 fn make_foreign_items(self: Box
<Self>) -> Option
<SmallVec
<[P
<ast
::ForeignItem
>; 1]>> {
399 /// Creates a pattern.
400 fn make_pat(self: Box
<Self>) -> Option
<P
<ast
::Pat
>> {
404 /// Creates zero or more statements.
406 /// By default this attempts to create an expression statement,
407 /// returning None if that fails.
408 fn make_stmts(self: Box
<Self>) -> Option
<SmallVec
<[ast
::Stmt
; 1]>> {
409 make_stmts_default
!(self)
412 fn make_ty(self: Box
<Self>) -> Option
<P
<ast
::Ty
>> {
416 fn make_arms(self: Box
<Self>) -> Option
<SmallVec
<[ast
::Arm
; 1]>> {
420 fn make_expr_fields(self: Box
<Self>) -> Option
<SmallVec
<[ast
::ExprField
; 1]>> {
424 fn make_pat_fields(self: Box
<Self>) -> Option
<SmallVec
<[ast
::PatField
; 1]>> {
428 fn make_generic_params(self: Box
<Self>) -> Option
<SmallVec
<[ast
::GenericParam
; 1]>> {
432 fn make_params(self: Box
<Self>) -> Option
<SmallVec
<[ast
::Param
; 1]>> {
436 fn make_field_defs(self: Box
<Self>) -> Option
<SmallVec
<[ast
::FieldDef
; 1]>> {
440 fn make_variants(self: Box
<Self>) -> Option
<SmallVec
<[ast
::Variant
; 1]>> {
444 fn make_crate(self: Box
<Self>) -> Option
<ast
::Crate
> {
445 // Fn-like macros cannot produce a crate.
450 macro_rules
! make_MacEager
{
451 ( $
( $fld
:ident
: $t
:ty
, )* ) => {
452 /// `MacResult` implementation for the common case where you've already
453 /// built each form of AST that you might return.
455 pub struct MacEager
{
457 pub $fld
: Option
<$t
>,
463 pub fn $
fld(v
: $t
) -> Box
<dyn MacResult
> {
477 items
: SmallVec
<[P
<ast
::Item
>; 1]>,
478 impl_items
: SmallVec
<[P
<ast
::AssocItem
>; 1]>,
479 trait_items
: SmallVec
<[P
<ast
::AssocItem
>; 1]>,
480 foreign_items
: SmallVec
<[P
<ast
::ForeignItem
>; 1]>,
481 stmts
: SmallVec
<[ast
::Stmt
; 1]>,
485 impl MacResult
for MacEager
{
486 fn make_expr(self: Box
<Self>) -> Option
<P
<ast
::Expr
>> {
490 fn make_items(self: Box
<Self>) -> Option
<SmallVec
<[P
<ast
::Item
>; 1]>> {
494 fn make_impl_items(self: Box
<Self>) -> Option
<SmallVec
<[P
<ast
::AssocItem
>; 1]>> {
498 fn make_trait_items(self: Box
<Self>) -> Option
<SmallVec
<[P
<ast
::AssocItem
>; 1]>> {
502 fn make_foreign_items(self: Box
<Self>) -> Option
<SmallVec
<[P
<ast
::ForeignItem
>; 1]>> {
506 fn make_stmts(self: Box
<Self>) -> Option
<SmallVec
<[ast
::Stmt
; 1]>> {
507 match self.stmts
.as_ref().map_or(0, |s
| s
.len()) {
508 0 => make_stmts_default
!(self),
513 fn make_pat(self: Box
<Self>) -> Option
<P
<ast
::Pat
>> {
514 if let Some(p
) = self.pat
{
517 if let Some(e
) = self.expr
{
518 if matches
!(e
.kind
, ast
::ExprKind
::Lit(_
) | ast
::ExprKind
::IncludedBytes(_
)) {
519 return Some(P(ast
::Pat
{
520 id
: ast
::DUMMY_NODE_ID
,
522 kind
: PatKind
::Lit(e
),
530 fn make_ty(self: Box
<Self>) -> Option
<P
<ast
::Ty
>> {
535 /// Fill-in macro expansion result, to allow compilation to continue
536 /// after hitting errors.
537 #[derive(Copy, Clone)]
538 pub struct DummyResult
{
544 /// Creates a default MacResult that can be anything.
546 /// Use this as a return value after hitting any errors and
547 /// calling `span_err`.
548 pub fn any(span
: Span
) -> Box
<dyn MacResult
+ '
static> {
549 Box
::new(DummyResult { is_error: true, span }
)
552 /// Same as `any`, but must be a valid fragment, not error.
553 pub fn any_valid(span
: Span
) -> Box
<dyn MacResult
+ '
static> {
554 Box
::new(DummyResult { is_error: false, span }
)
557 /// A plain dummy expression.
558 pub fn raw_expr(sp
: Span
, is_error
: bool
) -> P
<ast
::Expr
> {
560 id
: ast
::DUMMY_NODE_ID
,
561 kind
: if is_error { ast::ExprKind::Err }
else { ast::ExprKind::Tup(Vec::new()) }
,
563 attrs
: ast
::AttrVec
::new(),
568 /// A plain dummy pattern.
569 pub fn raw_pat(sp
: Span
) -> ast
::Pat
{
570 ast
::Pat { id: ast::DUMMY_NODE_ID, kind: PatKind::Wild, span: sp, tokens: None }
573 /// A plain dummy type.
574 pub fn raw_ty(sp
: Span
, is_error
: bool
) -> P
<ast
::Ty
> {
576 id
: ast
::DUMMY_NODE_ID
,
577 kind
: if is_error { ast::TyKind::Err }
else { ast::TyKind::Tup(Vec::new()) }
,
584 impl MacResult
for DummyResult
{
585 fn make_expr(self: Box
<DummyResult
>) -> Option
<P
<ast
::Expr
>> {
586 Some(DummyResult
::raw_expr(self.span
, self.is_error
))
589 fn make_pat(self: Box
<DummyResult
>) -> Option
<P
<ast
::Pat
>> {
590 Some(P(DummyResult
::raw_pat(self.span
)))
593 fn make_items(self: Box
<DummyResult
>) -> Option
<SmallVec
<[P
<ast
::Item
>; 1]>> {
594 Some(SmallVec
::new())
597 fn make_impl_items(self: Box
<DummyResult
>) -> Option
<SmallVec
<[P
<ast
::AssocItem
>; 1]>> {
598 Some(SmallVec
::new())
601 fn make_trait_items(self: Box
<DummyResult
>) -> Option
<SmallVec
<[P
<ast
::AssocItem
>; 1]>> {
602 Some(SmallVec
::new())
605 fn make_foreign_items(self: Box
<Self>) -> Option
<SmallVec
<[P
<ast
::ForeignItem
>; 1]>> {
606 Some(SmallVec
::new())
609 fn make_stmts(self: Box
<DummyResult
>) -> Option
<SmallVec
<[ast
::Stmt
; 1]>> {
610 Some(smallvec
![ast
::Stmt
{
611 id
: ast
::DUMMY_NODE_ID
,
612 kind
: ast
::StmtKind
::Expr(DummyResult
::raw_expr(self.span
, self.is_error
)),
617 fn make_ty(self: Box
<DummyResult
>) -> Option
<P
<ast
::Ty
>> {
618 Some(DummyResult
::raw_ty(self.span
, self.is_error
))
621 fn make_arms(self: Box
<DummyResult
>) -> Option
<SmallVec
<[ast
::Arm
; 1]>> {
622 Some(SmallVec
::new())
625 fn make_expr_fields(self: Box
<DummyResult
>) -> Option
<SmallVec
<[ast
::ExprField
; 1]>> {
626 Some(SmallVec
::new())
629 fn make_pat_fields(self: Box
<DummyResult
>) -> Option
<SmallVec
<[ast
::PatField
; 1]>> {
630 Some(SmallVec
::new())
633 fn make_generic_params(self: Box
<DummyResult
>) -> Option
<SmallVec
<[ast
::GenericParam
; 1]>> {
634 Some(SmallVec
::new())
637 fn make_params(self: Box
<DummyResult
>) -> Option
<SmallVec
<[ast
::Param
; 1]>> {
638 Some(SmallVec
::new())
641 fn make_field_defs(self: Box
<DummyResult
>) -> Option
<SmallVec
<[ast
::FieldDef
; 1]>> {
642 Some(SmallVec
::new())
645 fn make_variants(self: Box
<DummyResult
>) -> Option
<SmallVec
<[ast
::Variant
; 1]>> {
646 Some(SmallVec
::new())
650 /// A syntax extension kind.
651 pub enum SyntaxExtensionKind
{
652 /// A token-based function-like macro.
654 /// An expander with signature TokenStream -> TokenStream.
655 Box
<dyn BangProcMacro
+ sync
::Sync
+ sync
::Send
>,
658 /// An AST-based function-like macro.
660 /// An expander with signature TokenStream -> AST.
661 Box
<dyn TTMacroExpander
+ sync
::Sync
+ sync
::Send
>,
664 /// A token-based attribute macro.
666 /// An expander with signature (TokenStream, TokenStream) -> TokenStream.
667 /// The first TokenSteam is the attribute itself, the second is the annotated item.
668 /// The produced TokenSteam replaces the input TokenSteam.
669 Box
<dyn AttrProcMacro
+ sync
::Sync
+ sync
::Send
>,
672 /// An AST-based attribute macro.
674 /// An expander with signature (AST, AST) -> AST.
675 /// The first AST fragment is the attribute itself, the second is the annotated item.
676 /// The produced AST fragment replaces the input AST fragment.
677 Box
<dyn MultiItemModifier
+ sync
::Sync
+ sync
::Send
>,
680 /// A trivial attribute "macro" that does nothing,
681 /// only keeps the attribute and marks it as inert,
682 /// thus making it ineligible for further expansion.
685 /// A token-based derive macro.
687 /// An expander with signature TokenStream -> TokenStream.
688 /// The produced TokenSteam is appended to the input TokenSteam.
690 /// FIXME: The text above describes how this should work. Currently it
691 /// is handled identically to `LegacyDerive`. It should be migrated to
692 /// a token-based representation like `Bang` and `Attr`, instead of
693 /// using `MultiItemModifier`.
694 Box
<dyn MultiItemModifier
+ sync
::Sync
+ sync
::Send
>,
697 /// An AST-based derive macro.
699 /// An expander with signature AST -> AST.
700 /// The produced AST fragment is appended to the input AST fragment.
701 Box
<dyn MultiItemModifier
+ sync
::Sync
+ sync
::Send
>,
705 /// A struct representing a macro definition in "lowered" form ready for expansion.
706 pub struct SyntaxExtension
{
707 /// A syntax extension kind.
708 pub kind
: SyntaxExtensionKind
,
709 /// Span of the macro definition.
711 /// List of unstable features that are treated as stable inside this macro.
712 pub allow_internal_unstable
: Option
<Lrc
<[Symbol
]>>,
713 /// The macro's stability info.
714 pub stability
: Option
<Stability
>,
715 /// The macro's deprecation info.
716 pub deprecation
: Option
<Deprecation
>,
717 /// Names of helper attributes registered by this macro.
718 pub helper_attrs
: Vec
<Symbol
>,
719 /// Edition of the crate in which this macro is defined.
720 pub edition
: Edition
,
721 /// Built-in macros have a couple of special properties like availability
722 /// in `#[no_implicit_prelude]` modules, so we have to keep this flag.
723 pub builtin_name
: Option
<Symbol
>,
724 /// Suppresses the `unsafe_code` lint for code produced by this macro.
725 pub allow_internal_unsafe
: bool
,
726 /// Enables the macro helper hack (`ident!(...)` -> `$crate::ident!(...)`) for this macro.
727 pub local_inner_macros
: bool
,
728 /// Should debuginfo for the macro be collapsed to the outermost expansion site (in other
729 /// words, was the macro definition annotated with `#[collapse_debuginfo]`)?
730 pub collapse_debuginfo
: bool
,
733 impl SyntaxExtension
{
734 /// Returns which kind of macro calls this syntax extension.
735 pub fn macro_kind(&self) -> MacroKind
{
737 SyntaxExtensionKind
::Bang(..) | SyntaxExtensionKind
::LegacyBang(..) => MacroKind
::Bang
,
738 SyntaxExtensionKind
::Attr(..)
739 | SyntaxExtensionKind
::LegacyAttr(..)
740 | SyntaxExtensionKind
::NonMacroAttr
=> MacroKind
::Attr
,
741 SyntaxExtensionKind
::Derive(..) | SyntaxExtensionKind
::LegacyDerive(..) => {
747 /// Constructs a syntax extension with default properties.
748 pub fn default(kind
: SyntaxExtensionKind
, edition
: Edition
) -> SyntaxExtension
{
751 allow_internal_unstable
: None
,
754 helper_attrs
: Vec
::new(),
758 allow_internal_unsafe
: false,
759 local_inner_macros
: false,
760 collapse_debuginfo
: false,
764 /// Constructs a syntax extension with the given properties
765 /// and other properties converted from attributes.
768 kind
: SyntaxExtensionKind
,
770 helper_attrs
: Vec
<Symbol
>,
773 attrs
: &[ast
::Attribute
],
774 ) -> SyntaxExtension
{
775 let allow_internal_unstable
=
776 attr
::allow_internal_unstable(sess
, &attrs
).collect
::<Vec
<Symbol
>>();
778 let allow_internal_unsafe
= sess
.contains_name(attrs
, sym
::allow_internal_unsafe
);
779 let local_inner_macros
= sess
780 .find_by_name(attrs
, sym
::macro_export
)
781 .and_then(|macro_export
| macro_export
.meta_item_list())
782 .map_or(false, |l
| attr
::list_contains_name(&l
, sym
::local_inner_macros
));
783 let collapse_debuginfo
= sess
.contains_name(attrs
, sym
::collapse_debuginfo
);
784 tracing
::debug
!(?local_inner_macros
, ?collapse_debuginfo
, ?allow_internal_unsafe
);
786 let (builtin_name
, helper_attrs
) = sess
787 .find_by_name(attrs
, sym
::rustc_builtin_macro
)
789 // Override `helper_attrs` passed above if it's a built-in macro,
790 // marking `proc_macro_derive` macros as built-in is not a realistic use case.
791 parse_macro_name_and_helper_attrs(sess
.diagnostic(), attr
, "built-in").map_or_else(
792 || (Some(name
), Vec
::new()),
793 |(name
, helper_attrs
)| (Some(name
), helper_attrs
),
796 .unwrap_or_else(|| (None
, helper_attrs
));
797 let (stability
, const_stability
, body_stability
) = attr
::find_stability(&sess
, attrs
, span
);
798 if let Some((_
, sp
)) = const_stability
{
799 sess
.emit_err(MacroConstStability
{
801 head_span
: sess
.source_map().guess_head_span(span
),
804 if let Some((_
, sp
)) = body_stability
{
805 sess
.emit_err(MacroBodyStability
{
807 head_span
: sess
.source_map().guess_head_span(span
),
814 allow_internal_unstable
: (!allow_internal_unstable
.is_empty())
815 .then(|| allow_internal_unstable
.into()),
816 stability
: stability
.map(|(s
, _
)| s
),
817 deprecation
: attr
::find_deprecation(&sess
, attrs
).map(|(d
, _
)| d
),
821 allow_internal_unsafe
,
827 pub fn dummy_bang(edition
: Edition
) -> SyntaxExtension
{
829 _
: &'cx
mut ExtCtxt
<'_
>,
832 ) -> Box
<dyn MacResult
+ 'cx
> {
833 DummyResult
::any(span
)
835 SyntaxExtension
::default(SyntaxExtensionKind
::LegacyBang(Box
::new(expander
)), edition
)
838 pub fn dummy_derive(edition
: Edition
) -> SyntaxExtension
{
844 ) -> Vec
<Annotatable
> {
847 SyntaxExtension
::default(SyntaxExtensionKind
::Derive(Box
::new(expander
)), edition
)
850 pub fn non_macro_attr(edition
: Edition
) -> SyntaxExtension
{
851 SyntaxExtension
::default(SyntaxExtensionKind
::NonMacroAttr
, edition
)
859 macro_def_id
: Option
<DefId
>,
860 parent_module
: Option
<DefId
>,
863 ExpnKind
::Macro(self.macro_kind(), descr
),
867 self.allow_internal_unstable
.clone(),
871 self.allow_internal_unsafe
,
872 self.local_inner_macros
,
873 self.collapse_debuginfo
,
878 /// Error type that denotes indeterminacy.
879 pub struct Indeterminate
;
881 pub type DeriveResolutions
= Vec
<(ast
::Path
, Annotatable
, Option
<Lrc
<SyntaxExtension
>>, bool
)>;
883 pub trait ResolverExpand
{
884 fn next_node_id(&mut self) -> NodeId
;
885 fn invocation_parent(&self, id
: LocalExpnId
) -> LocalDefId
;
887 fn resolve_dollar_crates(&mut self);
888 fn visit_ast_fragment_with_placeholders(
890 expn_id
: LocalExpnId
,
891 fragment
: &AstFragment
,
893 fn register_builtin_macro(&mut self, name
: Symbol
, ext
: SyntaxExtensionKind
);
895 fn expansion_for_ast_pass(
900 parent_module_id
: Option
<NodeId
>,
903 fn resolve_imports(&mut self);
905 fn resolve_macro_invocation(
908 eager_expansion_root
: LocalExpnId
,
910 ) -> Result
<Lrc
<SyntaxExtension
>, Indeterminate
>;
912 fn record_macro_rule_usage(&mut self, mac_id
: NodeId
, rule_index
: usize);
914 fn check_unused_macros(&mut self);
916 // Resolver interfaces for specific built-in macros.
917 /// Does `#[derive(...)]` attribute with the given `ExpnId` have built-in `Copy` inside it?
918 fn has_derive_copy(&self, expn_id
: LocalExpnId
) -> bool
;
919 /// Resolve paths inside the `#[derive(...)]` attribute with the given `ExpnId`.
922 expn_id
: LocalExpnId
,
924 derive_paths
: &dyn Fn() -> DeriveResolutions
,
925 ) -> Result
<(), Indeterminate
>;
926 /// Take resolutions for paths inside the `#[derive(...)]` attribute with the given `ExpnId`
927 /// back from resolver.
928 fn take_derive_resolutions(&mut self, expn_id
: LocalExpnId
) -> Option
<DeriveResolutions
>;
929 /// Path resolution logic for `#[cfg_accessible(path)]`.
932 expn_id
: LocalExpnId
,
934 ) -> Result
<bool
, Indeterminate
>;
936 /// Decodes the proc-macro quoted span in the specified crate, with the specified id.
937 /// No caching is performed.
938 fn get_proc_macro_quoted_span(&self, krate
: CrateNum
, id
: usize) -> Span
;
940 /// The order of items in the HIR is unrelated to the order of
941 /// items in the AST. However, we generate proc macro harnesses
942 /// based on the AST order, and later refer to these harnesses
943 /// from the HIR. This field keeps track of the order in which
944 /// we generated proc macros harnesses, so that we can map
945 /// HIR proc macros items back to their harness items.
946 fn declare_proc_macro(&mut self, id
: NodeId
);
948 /// Tools registered with `#![register_tool]` and used by tool attributes and lints.
949 fn registered_tools(&self) -> &FxHashSet
<Ident
>;
952 pub trait LintStoreExpand
{
953 fn pre_expansion_lint(
956 registered_tools
: &FxHashSet
<Ident
>,
964 type LintStoreExpandDyn
<'a
> = Option
<&'
a (dyn LintStoreExpand
+ 'a
)>;
966 #[derive(Clone, Default)]
967 pub struct ModuleData
{
968 /// Path to the module starting from the crate name, like `my_crate::foo::bar`.
969 pub mod_path
: Vec
<Ident
>,
970 /// Stack of paths to files loaded by out-of-line module items,
971 /// used to detect and report recursive module inclusions.
972 pub file_path_stack
: Vec
<PathBuf
>,
973 /// Directory to search child module files in,
974 /// often (but not necessarily) the parent of the top file path on the `file_path_stack`.
975 pub dir_path
: PathBuf
,
979 pub fn with_dir_path(&self, dir_path
: PathBuf
) -> ModuleData
{
981 mod_path
: self.mod_path
.clone(),
982 file_path_stack
: self.file_path_stack
.clone(),
989 pub struct ExpansionData
{
992 pub module
: Rc
<ModuleData
>,
993 pub dir_ownership
: DirOwnership
,
994 pub prior_type_ascription
: Option
<(Span
, bool
)>,
995 /// Some parent node that is close to this macro call
996 pub lint_node_id
: NodeId
,
997 pub is_trailing_mac
: bool
,
1000 /// One of these is made during expansion and incrementally updated as we go;
1001 /// when a macro expansion occurs, the resulting nodes have the `backtrace()
1002 /// -> expn_data` of their expansion context stored into their span.
1003 pub struct ExtCtxt
<'a
> {
1004 pub sess
: &'a Session
,
1005 pub ecfg
: expand
::ExpansionConfig
<'a
>,
1006 pub reduced_recursion_limit
: Option
<Limit
>,
1007 pub root_path
: PathBuf
,
1008 pub resolver
: &'a
mut dyn ResolverExpand
,
1009 pub current_expansion
: ExpansionData
,
1010 /// Error recovery mode entered when expansion is stuck
1011 /// (or during eager expansion, but that's a hack).
1012 pub force_mode
: bool
,
1013 pub expansions
: FxIndexMap
<Span
, Vec
<String
>>,
1014 /// Used for running pre-expansion lints on freshly loaded modules.
1015 pub(super) lint_store
: LintStoreExpandDyn
<'a
>,
1016 /// Used for storing lints generated during expansion, like `NAMED_ARGUMENTS_USED_POSITIONALLY`
1017 pub buffered_early_lint
: Vec
<BufferedEarlyLint
>,
1018 /// When we 'expand' an inert attribute, we leave it
1019 /// in the AST, but insert it here so that we know
1020 /// not to expand it again.
1021 pub(super) expanded_inert_attrs
: MarkedAttrs
,
1024 impl<'a
> ExtCtxt
<'a
> {
1027 ecfg
: expand
::ExpansionConfig
<'a
>,
1028 resolver
: &'a
mut dyn ResolverExpand
,
1029 lint_store
: LintStoreExpandDyn
<'a
>,
1034 reduced_recursion_limit
: None
,
1037 root_path
: PathBuf
::new(),
1038 current_expansion
: ExpansionData
{
1039 id
: LocalExpnId
::ROOT
,
1041 module
: Default
::default(),
1042 dir_ownership
: DirOwnership
::Owned { relative: None }
,
1043 prior_type_ascription
: None
,
1044 lint_node_id
: ast
::CRATE_NODE_ID
,
1045 is_trailing_mac
: false,
1048 expansions
: FxIndexMap
::default(),
1049 expanded_inert_attrs
: MarkedAttrs
::new(),
1050 buffered_early_lint
: vec
![],
1054 /// Returns a `Folder` for deeply expanding all macros in an AST node.
1055 pub fn expander
<'b
>(&'b
mut self) -> expand
::MacroExpander
<'b
, 'a
> {
1056 expand
::MacroExpander
::new(self, false)
1059 /// Returns a `Folder` that deeply expands all macros and assigns all `NodeId`s in an AST node.
1060 /// Once `NodeId`s are assigned, the node may not be expanded, removed, or otherwise modified.
1061 pub fn monotonic_expander
<'b
>(&'b
mut self) -> expand
::MacroExpander
<'b
, 'a
> {
1062 expand
::MacroExpander
::new(self, true)
1064 pub fn new_parser_from_tts(&self, stream
: TokenStream
) -> parser
::Parser
<'a
> {
1065 rustc_parse
::stream_to_parser(&self.sess
.parse_sess
, stream
, MACRO_ARGUMENTS
)
1067 pub fn source_map(&self) -> &'a SourceMap
{
1068 self.sess
.parse_sess
.source_map()
1070 pub fn parse_sess(&self) -> &'a ParseSess
{
1071 &self.sess
.parse_sess
1073 pub fn call_site(&self) -> Span
{
1074 self.current_expansion
.id
.expn_data().call_site
1077 /// Returns the current expansion kind's description.
1078 pub(crate) fn expansion_descr(&self) -> String
{
1079 let expn_data
= self.current_expansion
.id
.expn_data();
1080 expn_data
.kind
.descr()
1083 /// Equivalent of `Span::def_site` from the proc macro API,
1084 /// except that the location is taken from the span passed as an argument.
1085 pub fn with_def_site_ctxt(&self, span
: Span
) -> Span
{
1086 span
.with_def_site_ctxt(self.current_expansion
.id
.to_expn_id())
1089 /// Equivalent of `Span::call_site` from the proc macro API,
1090 /// except that the location is taken from the span passed as an argument.
1091 pub fn with_call_site_ctxt(&self, span
: Span
) -> Span
{
1092 span
.with_call_site_ctxt(self.current_expansion
.id
.to_expn_id())
1095 /// Equivalent of `Span::mixed_site` from the proc macro API,
1096 /// except that the location is taken from the span passed as an argument.
1097 pub fn with_mixed_site_ctxt(&self, span
: Span
) -> Span
{
1098 span
.with_mixed_site_ctxt(self.current_expansion
.id
.to_expn_id())
1101 /// Returns span for the macro which originally caused the current expansion to happen.
1103 /// Stops backtracing at include! boundary.
1104 pub fn expansion_cause(&self) -> Option
<Span
> {
1105 self.current_expansion
.id
.expansion_cause()
1108 #[rustc_lint_diagnostics]
1109 pub fn struct_span_err
<S
: Into
<MultiSpan
>>(
1113 ) -> DiagnosticBuilder
<'a
, ErrorGuaranteed
> {
1114 self.sess
.parse_sess
.span_diagnostic
.struct_span_err(sp
, msg
)
1119 err
: impl IntoDiagnostic
<'a
>,
1120 ) -> DiagnosticBuilder
<'a
, ErrorGuaranteed
> {
1121 self.sess
.create_err(err
)
1124 pub fn emit_err(&self, err
: impl IntoDiagnostic
<'a
>) -> ErrorGuaranteed
{
1125 self.sess
.emit_err(err
)
1128 /// Emit `msg` attached to `sp`, without immediately stopping
1131 /// Compilation will be stopped in the near future (at the end of
1132 /// the macro expansion phase).
1133 #[rustc_lint_diagnostics]
1134 pub fn span_err
<S
: Into
<MultiSpan
>>(&self, sp
: S
, msg
: &str) {
1135 self.sess
.parse_sess
.span_diagnostic
.span_err(sp
, msg
);
1137 #[rustc_lint_diagnostics]
1138 pub fn span_warn
<S
: Into
<MultiSpan
>>(&self, sp
: S
, msg
: &str) {
1139 self.sess
.parse_sess
.span_diagnostic
.span_warn(sp
, msg
);
1141 pub fn span_bug
<S
: Into
<MultiSpan
>>(&self, sp
: S
, msg
: &str) -> ! {
1142 self.sess
.parse_sess
.span_diagnostic
.span_bug(sp
, msg
);
1144 pub fn trace_macros_diag(&mut self) {
1145 for (sp
, notes
) in self.expansions
.iter() {
1146 let mut db
= self.sess
.parse_sess
.span_diagnostic
.span_note_diag(*sp
, "trace_macro");
1152 // Fixme: does this result in errors?
1153 self.expansions
.clear();
1155 pub fn bug(&self, msg
: &str) -> ! {
1156 self.sess
.parse_sess
.span_diagnostic
.bug(msg
);
1158 pub fn trace_macros(&self) -> bool
{
1161 pub fn set_trace_macros(&mut self, x
: bool
) {
1162 self.ecfg
.trace_mac
= x
1164 pub fn std_path(&self, components
: &[Symbol
]) -> Vec
<Ident
> {
1165 let def_site
= self.with_def_site_ctxt(DUMMY_SP
);
1166 iter
::once(Ident
::new(kw
::DollarCrate
, def_site
))
1167 .chain(components
.iter().map(|&s
| Ident
::with_dummy_span(s
)))
1170 pub fn def_site_path(&self, components
: &[Symbol
]) -> Vec
<Ident
> {
1171 let def_site
= self.with_def_site_ctxt(DUMMY_SP
);
1172 components
.iter().map(|&s
| Ident
::new(s
, def_site
)).collect()
1175 pub fn check_unused_macros(&mut self) {
1176 self.resolver
.check_unused_macros();
1180 /// Resolves a `path` mentioned inside Rust code, returning an absolute path.
1182 /// This unifies the logic used for resolving `include_X!`.
1183 pub fn resolve_path(
1184 parse_sess
: &ParseSess
,
1185 path
: impl Into
<PathBuf
>,
1187 ) -> PResult
<'_
, PathBuf
> {
1188 let path
= path
.into();
1190 // Relative paths are resolved relative to the file in which they are found
1191 // after macro expansion (that is, they are unhygienic).
1192 if !path
.is_absolute() {
1193 let callsite
= span
.source_callsite();
1194 let mut result
= match parse_sess
.source_map().span_to_filename(callsite
) {
1195 FileName
::Real(name
) => name
1197 .expect("attempting to resolve a file path in an external file"),
1198 FileName
::DocTest(path
, _
) => path
,
1200 return Err(ResolveRelativePath
{
1202 path
: parse_sess
.source_map().filename_for_diagnostics(&other
).to_string(),
1204 .into_diagnostic(&parse_sess
.span_diagnostic
));
1215 /// Extracts a string literal from the macro expanded version of `expr`,
1216 /// returning a diagnostic error of `err_msg` if `expr` is not a string literal.
1217 /// The returned bool indicates whether an applicable suggestion has already been
1218 /// added to the diagnostic to avoid emitting multiple suggestions. `Err(None)`
1219 /// indicates that an ast error was encountered.
1220 // FIXME(Nilstrieb) Make this function setup translatable
1221 #[allow(rustc::untranslatable_diagnostic)]
1222 pub fn expr_to_spanned_string
<'a
>(
1223 cx
: &'a
mut ExtCtxt
<'_
>,
1226 ) -> Result
<(Symbol
, ast
::StrStyle
, Span
), Option
<(DiagnosticBuilder
<'a
, ErrorGuaranteed
>, bool
)>> {
1227 // Perform eager expansion on the expression.
1228 // We want to be able to handle e.g., `concat!("foo", "bar")`.
1229 let expr
= cx
.expander().fully_expand_fragment(AstFragment
::Expr(expr
)).make_expr();
1231 Err(match expr
.kind
{
1232 ast
::ExprKind
::Lit(token_lit
) => match ast
::LitKind
::from_token_lit(token_lit
) {
1233 Ok(ast
::LitKind
::Str(s
, style
)) => return Ok((s
, style
, expr
.span
)),
1234 Ok(ast
::LitKind
::ByteStr(..)) => {
1235 let mut err
= cx
.struct_span_err(expr
.span
, err_msg
);
1236 let span
= expr
.span
.shrink_to_lo();
1237 err
.span_suggestion(
1238 span
.with_hi(span
.lo() + BytePos(1)),
1239 "consider removing the leading `b`",
1241 Applicability
::MaybeIncorrect
,
1245 Ok(ast
::LitKind
::Err
) => None
,
1247 report_lit_error(&cx
.sess
.parse_sess
, err
, token_lit
, expr
.span
);
1250 _
=> Some((cx
.struct_span_err(expr
.span
, err_msg
), false)),
1252 ast
::ExprKind
::Err
=> None
,
1253 _
=> Some((cx
.struct_span_err(expr
.span
, err_msg
), false)),
1257 /// Extracts a string literal from the macro expanded version of `expr`,
1258 /// emitting `err_msg` if `expr` is not a string literal. This does not stop
1259 /// compilation on error, merely emits a non-fatal error and returns `None`.
1260 pub fn expr_to_string(
1261 cx
: &mut ExtCtxt
<'_
>,
1264 ) -> Option
<(Symbol
, ast
::StrStyle
)> {
1265 expr_to_spanned_string(cx
, expr
, err_msg
)
1267 err
.map(|(mut err
, _
)| {
1272 .map(|(symbol
, style
, _
)| (symbol
, style
))
1275 /// Non-fatally assert that `tts` is empty. Note that this function
1276 /// returns even when `tts` is non-empty, macros that *need* to stop
1277 /// compilation should call
1278 /// `cx.parse_sess.span_diagnostic.abort_if_errors()` (this should be
1279 /// done as rarely as possible).
1280 pub fn check_zero_tts(cx
: &ExtCtxt
<'_
>, span
: Span
, tts
: TokenStream
, name
: &str) {
1281 if !tts
.is_empty() {
1282 cx
.emit_err(TakesNoArguments { span, name }
);
1286 /// Parse an expression. On error, emit it, advancing to `Eof`, and return `None`.
1287 pub fn parse_expr(p
: &mut parser
::Parser
<'_
>) -> Option
<P
<ast
::Expr
>> {
1288 match p
.parse_expr() {
1289 Ok(e
) => return Some(e
),
1294 while p
.token
!= token
::Eof
{
1300 /// Interpreting `tts` as a comma-separated sequence of expressions,
1301 /// expect exactly one string literal, or emit an error and return `None`.
1302 pub fn get_single_str_from_tts(
1303 cx
: &mut ExtCtxt
<'_
>,
1307 ) -> Option
<Symbol
> {
1308 let mut p
= cx
.new_parser_from_tts(tts
);
1309 if p
.token
== token
::Eof
{
1310 cx
.emit_err(OnlyOneArgument { span, name }
);
1313 let ret
= parse_expr(&mut p
)?
;
1314 let _
= p
.eat(&token
::Comma
);
1316 if p
.token
!= token
::Eof
{
1317 cx
.emit_err(OnlyOneArgument { span, name }
);
1319 expr_to_string(cx
, ret
, "argument must be a string literal").map(|(s
, _
)| s
)
1322 /// Extracts comma-separated expressions from `tts`.
1323 /// On error, emit it, and return `None`.
1324 pub fn get_exprs_from_tts(cx
: &mut ExtCtxt
<'_
>, tts
: TokenStream
) -> Option
<Vec
<P
<ast
::Expr
>>> {
1325 let mut p
= cx
.new_parser_from_tts(tts
);
1326 let mut es
= Vec
::new();
1327 while p
.token
!= token
::Eof
{
1328 let expr
= parse_expr(&mut p
)?
;
1330 // Perform eager expansion on the expression.
1331 // We want to be able to handle e.g., `concat!("foo", "bar")`.
1332 let expr
= cx
.expander().fully_expand_fragment(AstFragment
::Expr(expr
)).make_expr();
1335 if p
.eat(&token
::Comma
) {
1338 if p
.token
!= token
::Eof
{
1339 cx
.emit_err(ExpectedCommaInList { span: p.token.span }
);
1346 pub fn parse_macro_name_and_helper_attrs(
1347 diag
: &rustc_errors
::Handler
,
1350 ) -> Option
<(Symbol
, Vec
<Symbol
>)> {
1351 // Once we've located the `#[proc_macro_derive]` attribute, verify
1352 // that it's of the form `#[proc_macro_derive(Foo)]` or
1353 // `#[proc_macro_derive(Foo, attributes(A, ..))]`
1354 let list
= attr
.meta_item_list()?
;
1355 if list
.len() != 1 && list
.len() != 2 {
1356 diag
.emit_err(AttrNoArguments { span: attr.span }
);
1359 let Some(trait_attr
) = list
[0].meta_item() else {
1360 diag
.emit_err(NotAMetaItem {span: list[0].span()}
);
1363 let trait_ident
= match trait_attr
.ident() {
1364 Some(trait_ident
) if trait_attr
.is_word() => trait_ident
,
1366 diag
.emit_err(OnlyOneWord { span: trait_attr.span }
);
1371 if !trait_ident
.name
.can_be_raw() {
1372 diag
.emit_err(CannotBeNameOfMacro { span: trait_attr.span, trait_ident, macro_type }
);
1375 let attributes_attr
= list
.get(1);
1376 let proc_attrs
: Vec
<_
> = if let Some(attr
) = attributes_attr
{
1377 if !attr
.has_name(sym
::attributes
) {
1378 diag
.emit_err(ArgumentNotAttributes { span: attr.span() }
);
1380 attr
.meta_item_list()
1381 .unwrap_or_else(|| {
1382 diag
.emit_err(AttributesWrongForm { span: attr.span() }
);
1386 .filter_map(|attr
| {
1387 let Some(attr
) = attr
.meta_item() else {
1388 diag
.emit_err(AttributeMetaItem { span: attr.span() }
);
1392 let ident
= match attr
.ident() {
1393 Some(ident
) if attr
.is_word() => ident
,
1395 diag
.emit_err(AttributeSingleWord { span: attr.span }
);
1399 if !ident
.name
.can_be_raw() {
1400 diag
.emit_err(HelperAttributeNameInvalid { span: attr.span, name: ident }
);
1410 Some((trait_ident
.name
, proc_attrs
))
1413 /// This nonterminal looks like some specific enums from
1414 /// `proc-macro-hack` and `procedural-masquerade` crates.
1415 /// We need to maintain some special pretty-printing behavior for them due to incorrect
1416 /// asserts in old versions of those crates and their wide use in the ecosystem.
1417 /// See issue #73345 for more details.
1418 /// FIXME(#73933): Remove this eventually.
1419 fn pretty_printing_compatibility_hack(item
: &Item
, sess
: &ParseSess
) -> bool
{
1420 let name
= item
.ident
.name
;
1421 if name
== sym
::ProceduralMasqueradeDummyType
{
1422 if let ast
::ItemKind
::Enum(enum_def
, _
) = &item
.kind
{
1423 if let [variant
] = &*enum_def
.variants
{
1424 if variant
.ident
.name
== sym
::Input
{
1425 let filename
= sess
.source_map().span_to_filename(item
.ident
.span
);
1426 if let FileName
::Real(real
) = filename
{
1427 if let Some(c
) = real
1429 .unwrap_or(Path
::new(""))
1431 .flat_map(|c
| c
.as_os_str().to_str())
1432 .find(|c
| c
.starts_with("rental") || c
.starts_with("allsorts-rental"))
1434 let crate_matches
= if c
.starts_with("allsorts-rental") {
1437 let mut version
= c
.trim_start_matches("rental-").split('
.'
);
1438 version
.next() == Some("0")
1439 && version
.next() == Some("5")
1442 .and_then(|c
| c
.parse
::<u32>().ok())
1443 .map_or(false, |v
| v
< 6)
1447 sess
.buffer_lint_with_diagnostic(
1448 &PROC_MACRO_BACK_COMPAT
,
1451 "using an old version of `rental`",
1452 BuiltinLintDiagnostics
::ProcMacroBackCompat(
1453 "older versions of the `rental` crate will stop compiling in future versions of Rust; \
1454 please update to `rental` v0.5.6, or switch to one of the `rental` alternatives".to_string()
1468 pub(crate) fn ann_pretty_printing_compatibility_hack(ann
: &Annotatable
, sess
: &ParseSess
) -> bool
{
1469 let item
= match ann
{
1470 Annotatable
::Item(item
) => item
,
1471 Annotatable
::Stmt(stmt
) => match &stmt
.kind
{
1472 ast
::StmtKind
::Item(item
) => item
,
1477 pretty_printing_compatibility_hack(item
, sess
)
1480 pub(crate) fn nt_pretty_printing_compatibility_hack(nt
: &Nonterminal
, sess
: &ParseSess
) -> bool
{
1481 let item
= match nt
{
1482 Nonterminal
::NtItem(item
) => item
,
1483 Nonterminal
::NtStmt(stmt
) => match &stmt
.kind
{
1484 ast
::StmtKind
::Item(item
) => item
,
1489 pretty_printing_compatibility_hack(item
, sess
)