1 // Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 //! A Folder represents an AST->AST fold; it accepts an AST piece,
12 //! and returns a piece of the same type. So, for instance, macro
13 //! expansion is a Folder that walks over an AST and produces another
16 //! Note: using a Folder (other than the MacroExpander Folder) on
17 //! an AST before macro expansion is probably a bad idea. For instance,
18 //! a folder renaming item names in a module will miss all of those
19 //! that are created by the expansion of a macro.
24 use codemap
::{Spanned, respan}
;
25 use parse
::token
::{self, Token}
;
29 use util
::small_vector
::SmallVector
;
30 use util
::move_map
::MoveMap
;
32 use rustc_data_structures
::sync
::Lrc
;
34 pub trait Folder
: Sized
{
35 // Any additions to this trait should happen in form
36 // of a call to a public `noop_*` function that only calls
37 // out to the folder again, not other `noop_*` functions.
39 // This is a necessary API workaround to the problem of not
40 // being able to call out to the super default method
41 // in an overridden default method.
43 fn fold_crate(&mut self, c
: Crate
) -> Crate
{
44 noop_fold_crate(c
, self)
47 fn fold_meta_items(&mut self, meta_items
: Vec
<MetaItem
>) -> Vec
<MetaItem
> {
48 noop_fold_meta_items(meta_items
, self)
51 fn fold_meta_list_item(&mut self, list_item
: NestedMetaItem
) -> NestedMetaItem
{
52 noop_fold_meta_list_item(list_item
, self)
55 fn fold_meta_item(&mut self, meta_item
: MetaItem
) -> MetaItem
{
56 noop_fold_meta_item(meta_item
, self)
59 fn fold_use_tree(&mut self, use_tree
: UseTree
) -> UseTree
{
60 noop_fold_use_tree(use_tree
, self)
63 fn fold_foreign_item(&mut self, ni
: ForeignItem
) -> SmallVector
<ForeignItem
> {
64 noop_fold_foreign_item(ni
, self)
67 fn fold_foreign_item_simple(&mut self, ni
: ForeignItem
) -> ForeignItem
{
68 noop_fold_foreign_item_simple(ni
, self)
71 fn fold_item(&mut self, i
: P
<Item
>) -> SmallVector
<P
<Item
>> {
72 noop_fold_item(i
, self)
75 fn fold_item_simple(&mut self, i
: Item
) -> Item
{
76 noop_fold_item_simple(i
, self)
79 fn fold_struct_field(&mut self, sf
: StructField
) -> StructField
{
80 noop_fold_struct_field(sf
, self)
83 fn fold_item_kind(&mut self, i
: ItemKind
) -> ItemKind
{
84 noop_fold_item_kind(i
, self)
87 fn fold_trait_item(&mut self, i
: TraitItem
) -> SmallVector
<TraitItem
> {
88 noop_fold_trait_item(i
, self)
91 fn fold_impl_item(&mut self, i
: ImplItem
) -> SmallVector
<ImplItem
> {
92 noop_fold_impl_item(i
, self)
95 fn fold_fn_decl(&mut self, d
: P
<FnDecl
>) -> P
<FnDecl
> {
96 noop_fold_fn_decl(d
, self)
99 fn fold_block(&mut self, b
: P
<Block
>) -> P
<Block
> {
100 noop_fold_block(b
, self)
103 fn fold_stmt(&mut self, s
: Stmt
) -> SmallVector
<Stmt
> {
104 noop_fold_stmt(s
, self)
107 fn fold_arm(&mut self, a
: Arm
) -> Arm
{
108 noop_fold_arm(a
, self)
111 fn fold_pat(&mut self, p
: P
<Pat
>) -> P
<Pat
> {
112 noop_fold_pat(p
, self)
115 fn fold_expr(&mut self, e
: P
<Expr
>) -> P
<Expr
> {
116 e
.map(|e
| noop_fold_expr(e
, self))
119 fn fold_range_end(&mut self, re
: RangeEnd
) -> RangeEnd
{
120 noop_fold_range_end(re
, self)
123 fn fold_opt_expr(&mut self, e
: P
<Expr
>) -> Option
<P
<Expr
>> {
124 noop_fold_opt_expr(e
, self)
127 fn fold_exprs(&mut self, es
: Vec
<P
<Expr
>>) -> Vec
<P
<Expr
>> {
128 noop_fold_exprs(es
, self)
131 fn fold_ty(&mut self, t
: P
<Ty
>) -> P
<Ty
> {
132 noop_fold_ty(t
, self)
135 fn fold_ty_binding(&mut self, t
: TypeBinding
) -> TypeBinding
{
136 noop_fold_ty_binding(t
, self)
139 fn fold_mod(&mut self, m
: Mod
) -> Mod
{
140 noop_fold_mod(m
, self)
143 fn fold_foreign_mod(&mut self, nm
: ForeignMod
) -> ForeignMod
{
144 noop_fold_foreign_mod(nm
, self)
147 fn fold_global_asm(&mut self, ga
: P
<GlobalAsm
>) -> P
<GlobalAsm
> {
148 noop_fold_global_asm(ga
, self)
151 fn fold_variant(&mut self, v
: Variant
) -> Variant
{
152 noop_fold_variant(v
, self)
155 fn fold_ident(&mut self, i
: Ident
) -> Ident
{
156 noop_fold_ident(i
, self)
159 fn fold_usize(&mut self, i
: usize) -> usize {
160 noop_fold_usize(i
, self)
163 fn fold_path(&mut self, p
: Path
) -> Path
{
164 noop_fold_path(p
, self)
167 fn fold_path_parameters(&mut self, p
: PathParameters
) -> PathParameters
{
168 noop_fold_path_parameters(p
, self)
171 fn fold_angle_bracketed_parameter_data(&mut self, p
: AngleBracketedParameterData
)
172 -> AngleBracketedParameterData
174 noop_fold_angle_bracketed_parameter_data(p
, self)
177 fn fold_parenthesized_parameter_data(&mut self, p
: ParenthesizedParameterData
)
178 -> ParenthesizedParameterData
180 noop_fold_parenthesized_parameter_data(p
, self)
183 fn fold_local(&mut self, l
: P
<Local
>) -> P
<Local
> {
184 noop_fold_local(l
, self)
187 fn fold_mac(&mut self, _mac
: Mac
) -> Mac
{
188 panic
!("fold_mac disabled by default");
189 // NB: see note about macros above.
190 // if you really want a folder that
191 // works on macros, use this
192 // definition in your trait impl:
193 // fold::noop_fold_mac(_mac, self)
196 fn fold_macro_def(&mut self, def
: MacroDef
) -> MacroDef
{
197 noop_fold_macro_def(def
, self)
200 fn fold_label(&mut self, label
: Label
) -> Label
{
201 noop_fold_label(label
, self)
204 fn fold_lifetime(&mut self, l
: Lifetime
) -> Lifetime
{
205 noop_fold_lifetime(l
, self)
208 fn fold_lifetime_def(&mut self, l
: LifetimeDef
) -> LifetimeDef
{
209 noop_fold_lifetime_def(l
, self)
212 fn fold_attribute(&mut self, at
: Attribute
) -> Option
<Attribute
> {
213 noop_fold_attribute(at
, self)
216 fn fold_arg(&mut self, a
: Arg
) -> Arg
{
217 noop_fold_arg(a
, self)
220 fn fold_generics(&mut self, generics
: Generics
) -> Generics
{
221 noop_fold_generics(generics
, self)
224 fn fold_trait_ref(&mut self, p
: TraitRef
) -> TraitRef
{
225 noop_fold_trait_ref(p
, self)
228 fn fold_poly_trait_ref(&mut self, p
: PolyTraitRef
) -> PolyTraitRef
{
229 noop_fold_poly_trait_ref(p
, self)
232 fn fold_variant_data(&mut self, vdata
: VariantData
) -> VariantData
{
233 noop_fold_variant_data(vdata
, self)
236 fn fold_lifetimes(&mut self, lts
: Vec
<Lifetime
>) -> Vec
<Lifetime
> {
237 noop_fold_lifetimes(lts
, self)
240 fn fold_lifetime_defs(&mut self, lts
: Vec
<LifetimeDef
>) -> Vec
<LifetimeDef
> {
241 noop_fold_lifetime_defs(lts
, self)
244 fn fold_ty_param(&mut self, tp
: TyParam
) -> TyParam
{
245 noop_fold_ty_param(tp
, self)
248 fn fold_generic_param(&mut self, param
: GenericParam
) -> GenericParam
{
249 noop_fold_generic_param(param
, self)
252 fn fold_generic_params(&mut self, params
: Vec
<GenericParam
>) -> Vec
<GenericParam
> {
253 noop_fold_generic_params(params
, self)
256 fn fold_tt(&mut self, tt
: TokenTree
) -> TokenTree
{
257 noop_fold_tt(tt
, self)
260 fn fold_tts(&mut self, tts
: TokenStream
) -> TokenStream
{
261 noop_fold_tts(tts
, self)
264 fn fold_token(&mut self, t
: token
::Token
) -> token
::Token
{
265 noop_fold_token(t
, self)
268 fn fold_interpolated(&mut self, nt
: token
::Nonterminal
) -> token
::Nonterminal
{
269 noop_fold_interpolated(nt
, self)
272 fn fold_opt_lifetime(&mut self, o_lt
: Option
<Lifetime
>) -> Option
<Lifetime
> {
273 noop_fold_opt_lifetime(o_lt
, self)
276 fn fold_opt_bounds(&mut self, b
: Option
<TyParamBounds
>)
277 -> Option
<TyParamBounds
> {
278 noop_fold_opt_bounds(b
, self)
281 fn fold_bounds(&mut self, b
: TyParamBounds
)
283 noop_fold_bounds(b
, self)
286 fn fold_ty_param_bound(&mut self, tpb
: TyParamBound
) -> TyParamBound
{
287 noop_fold_ty_param_bound(tpb
, self)
290 fn fold_mt(&mut self, mt
: MutTy
) -> MutTy
{
291 noop_fold_mt(mt
, self)
294 fn fold_field(&mut self, field
: Field
) -> Field
{
295 noop_fold_field(field
, self)
298 fn fold_where_clause(&mut self, where_clause
: WhereClause
)
300 noop_fold_where_clause(where_clause
, self)
303 fn fold_where_predicate(&mut self, where_predicate
: WherePredicate
)
305 noop_fold_where_predicate(where_predicate
, self)
308 fn fold_vis(&mut self, vis
: Visibility
) -> Visibility
{
309 noop_fold_vis(vis
, self)
312 fn new_id(&mut self, i
: NodeId
) -> NodeId
{
316 fn new_span(&mut self, sp
: Span
) -> Span
{
321 pub fn noop_fold_meta_items
<T
: Folder
>(meta_items
: Vec
<MetaItem
>, fld
: &mut T
) -> Vec
<MetaItem
> {
322 meta_items
.move_map(|x
| fld
.fold_meta_item(x
))
325 pub fn noop_fold_use_tree
<T
: Folder
>(use_tree
: UseTree
, fld
: &mut T
) -> UseTree
{
327 span
: fld
.new_span(use_tree
.span
),
328 prefix
: fld
.fold_path(use_tree
.prefix
),
329 kind
: match use_tree
.kind
{
330 UseTreeKind
::Simple(rename
) =>
331 UseTreeKind
::Simple(rename
.map(|ident
| fld
.fold_ident(ident
))),
332 UseTreeKind
::Glob
=> UseTreeKind
::Glob
,
333 UseTreeKind
::Nested(items
) => UseTreeKind
::Nested(items
.move_map(|(tree
, id
)| {
334 (fld
.fold_use_tree(tree
), fld
.new_id(id
))
340 pub fn fold_attrs
<T
: Folder
>(attrs
: Vec
<Attribute
>, fld
: &mut T
) -> Vec
<Attribute
> {
341 attrs
.move_flat_map(|x
| fld
.fold_attribute(x
))
344 pub fn fold_thin_attrs
<T
: Folder
>(attrs
: ThinVec
<Attribute
>, fld
: &mut T
) -> ThinVec
<Attribute
> {
345 fold_attrs(attrs
.into(), fld
).into()
348 pub fn noop_fold_arm
<T
: Folder
>(Arm {attrs, pats, guard, body}
: Arm
,
349 fld
: &mut T
) -> Arm
{
351 attrs
: fold_attrs(attrs
, fld
),
352 pats
: pats
.move_map(|x
| fld
.fold_pat(x
)),
353 guard
: guard
.map(|x
| fld
.fold_expr(x
)),
354 body
: fld
.fold_expr(body
),
358 pub fn noop_fold_ty_binding
<T
: Folder
>(b
: TypeBinding
, fld
: &mut T
) -> TypeBinding
{
360 id
: fld
.new_id(b
.id
),
361 ident
: fld
.fold_ident(b
.ident
),
362 ty
: fld
.fold_ty(b
.ty
),
363 span
: fld
.new_span(b
.span
),
367 pub fn noop_fold_ty
<T
: Folder
>(t
: P
<Ty
>, fld
: &mut T
) -> P
<Ty
> {
368 t
.map(|Ty {id, node, span}
| Ty
{
371 TyKind
::Infer
| TyKind
::ImplicitSelf
| TyKind
::Err
=> node
,
372 TyKind
::Slice(ty
) => TyKind
::Slice(fld
.fold_ty(ty
)),
373 TyKind
::Ptr(mt
) => TyKind
::Ptr(fld
.fold_mt(mt
)),
374 TyKind
::Rptr(region
, mt
) => {
375 TyKind
::Rptr(fld
.fold_opt_lifetime(region
), fld
.fold_mt(mt
))
377 TyKind
::BareFn(f
) => {
378 TyKind
::BareFn(f
.map(|BareFnTy {generic_params, unsafety, abi, decl}
| BareFnTy
{
379 generic_params
: fld
.fold_generic_params(generic_params
),
382 decl
: fld
.fold_fn_decl(decl
)
385 TyKind
::Never
=> node
,
386 TyKind
::Tup(tys
) => TyKind
::Tup(tys
.move_map(|ty
| fld
.fold_ty(ty
))),
387 TyKind
::Paren(ty
) => TyKind
::Paren(fld
.fold_ty(ty
)),
388 TyKind
::Path(qself
, path
) => {
389 let qself
= qself
.map(|QSelf { ty, position }
| {
395 TyKind
::Path(qself
, fld
.fold_path(path
))
397 TyKind
::Array(ty
, e
) => {
398 TyKind
::Array(fld
.fold_ty(ty
), fld
.fold_expr(e
))
400 TyKind
::Typeof(expr
) => {
401 TyKind
::Typeof(fld
.fold_expr(expr
))
403 TyKind
::TraitObject(bounds
, syntax
) => {
404 TyKind
::TraitObject(bounds
.move_map(|b
| fld
.fold_ty_param_bound(b
)), syntax
)
406 TyKind
::ImplTrait(bounds
) => {
407 TyKind
::ImplTrait(bounds
.move_map(|b
| fld
.fold_ty_param_bound(b
)))
409 TyKind
::Mac(mac
) => {
410 TyKind
::Mac(fld
.fold_mac(mac
))
413 span
: fld
.new_span(span
)
417 pub fn noop_fold_foreign_mod
<T
: Folder
>(ForeignMod {abi, items}
: ForeignMod
,
418 fld
: &mut T
) -> ForeignMod
{
421 items
: items
.move_flat_map(|x
| fld
.fold_foreign_item(x
)),
425 pub fn noop_fold_global_asm
<T
: Folder
>(ga
: P
<GlobalAsm
>,
426 _
: &mut T
) -> P
<GlobalAsm
> {
430 pub fn noop_fold_variant
<T
: Folder
>(v
: Variant
, fld
: &mut T
) -> Variant
{
433 ident
: fld
.fold_ident(v
.node
.ident
),
434 attrs
: fold_attrs(v
.node
.attrs
, fld
),
435 data
: fld
.fold_variant_data(v
.node
.data
),
436 disr_expr
: v
.node
.disr_expr
.map(|e
| fld
.fold_expr(e
)),
438 span
: fld
.new_span(v
.span
),
442 pub fn noop_fold_ident
<T
: Folder
>(ident
: Ident
, fld
: &mut T
) -> Ident
{
443 Ident
::new(ident
.name
, fld
.new_span(ident
.span
))
446 pub fn noop_fold_usize
<T
: Folder
>(i
: usize, _
: &mut T
) -> usize {
450 pub fn noop_fold_path
<T
: Folder
>(Path { segments, span }
: Path
, fld
: &mut T
) -> Path
{
452 segments
: segments
.move_map(|PathSegment {ident, parameters}
| PathSegment
{
453 ident
: fld
.fold_ident(ident
),
454 parameters
: parameters
.map(|ps
| ps
.map(|ps
| fld
.fold_path_parameters(ps
))),
456 span
: fld
.new_span(span
)
460 pub fn noop_fold_path_parameters
<T
: Folder
>(path_parameters
: PathParameters
, fld
: &mut T
)
463 match path_parameters
{
464 PathParameters
::AngleBracketed(data
) =>
465 PathParameters
::AngleBracketed(fld
.fold_angle_bracketed_parameter_data(data
)),
466 PathParameters
::Parenthesized(data
) =>
467 PathParameters
::Parenthesized(fld
.fold_parenthesized_parameter_data(data
)),
471 pub fn noop_fold_angle_bracketed_parameter_data
<T
: Folder
>(data
: AngleBracketedParameterData
,
473 -> AngleBracketedParameterData
475 let AngleBracketedParameterData { lifetimes, types, bindings, span }
= data
;
476 AngleBracketedParameterData
{ lifetimes
: fld
.fold_lifetimes(lifetimes
),
477 types
: types
.move_map(|ty
| fld
.fold_ty(ty
)),
478 bindings
: bindings
.move_map(|b
| fld
.fold_ty_binding(b
)),
479 span
: fld
.new_span(span
) }
482 pub fn noop_fold_parenthesized_parameter_data
<T
: Folder
>(data
: ParenthesizedParameterData
,
484 -> ParenthesizedParameterData
486 let ParenthesizedParameterData { inputs, output, span }
= data
;
487 ParenthesizedParameterData
{ inputs
: inputs
.move_map(|ty
| fld
.fold_ty(ty
)),
488 output
: output
.map(|ty
| fld
.fold_ty(ty
)),
489 span
: fld
.new_span(span
) }
492 pub fn noop_fold_local
<T
: Folder
>(l
: P
<Local
>, fld
: &mut T
) -> P
<Local
> {
493 l
.map(|Local {id, pat, ty, init, span, attrs}
| Local
{
495 pat
: fld
.fold_pat(pat
),
496 ty
: ty
.map(|t
| fld
.fold_ty(t
)),
497 init
: init
.map(|e
| fld
.fold_expr(e
)),
498 span
: fld
.new_span(span
),
499 attrs
: fold_attrs(attrs
.into(), fld
).into(),
503 pub fn noop_fold_attribute
<T
: Folder
>(attr
: Attribute
, fld
: &mut T
) -> Option
<Attribute
> {
507 path
: fld
.fold_path(attr
.path
),
508 tokens
: fld
.fold_tts(attr
.tokens
),
509 is_sugared_doc
: attr
.is_sugared_doc
,
510 span
: fld
.new_span(attr
.span
),
514 pub fn noop_fold_mac
<T
: Folder
>(Spanned {node, span}
: Mac
, fld
: &mut T
) -> Mac
{
517 tts
: fld
.fold_tts(node
.stream()).into(),
518 path
: fld
.fold_path(node
.path
),
520 span
: fld
.new_span(span
)
524 pub fn noop_fold_macro_def
<T
: Folder
>(def
: MacroDef
, fld
: &mut T
) -> MacroDef
{
526 tokens
: fld
.fold_tts(def
.tokens
.into()).into(),
531 pub fn noop_fold_meta_list_item
<T
: Folder
>(li
: NestedMetaItem
, fld
: &mut T
)
534 node
: match li
.node
{
535 NestedMetaItemKind
::MetaItem(mi
) => {
536 NestedMetaItemKind
::MetaItem(fld
.fold_meta_item(mi
))
538 NestedMetaItemKind
::Literal(lit
) => NestedMetaItemKind
::Literal(lit
)
540 span
: fld
.new_span(li
.span
)
544 pub fn noop_fold_meta_item
<T
: Folder
>(mi
: MetaItem
, fld
: &mut T
) -> MetaItem
{
547 node
: match mi
.node
{
548 MetaItemKind
::Word
=> MetaItemKind
::Word
,
549 MetaItemKind
::List(mis
) => {
550 MetaItemKind
::List(mis
.move_map(|e
| fld
.fold_meta_list_item(e
)))
552 MetaItemKind
::NameValue(s
) => MetaItemKind
::NameValue(s
),
554 span
: fld
.new_span(mi
.span
)
558 pub fn noop_fold_arg
<T
: Folder
>(Arg {id, pat, ty}
: Arg
, fld
: &mut T
) -> Arg
{
561 pat
: fld
.fold_pat(pat
),
566 pub fn noop_fold_tt
<T
: Folder
>(tt
: TokenTree
, fld
: &mut T
) -> TokenTree
{
568 TokenTree
::Token(span
, tok
) =>
569 TokenTree
::Token(fld
.new_span(span
), fld
.fold_token(tok
)),
570 TokenTree
::Delimited(span
, delimed
) => TokenTree
::Delimited(fld
.new_span(span
), Delimited
{
571 tts
: fld
.fold_tts(delimed
.stream()).into(),
572 delim
: delimed
.delim
,
577 pub fn noop_fold_tts
<T
: Folder
>(tts
: TokenStream
, fld
: &mut T
) -> TokenStream
{
578 tts
.map(|tt
| fld
.fold_tt(tt
))
581 // apply ident folder if it's an ident, apply other folds to interpolated nodes
582 pub fn noop_fold_token
<T
: Folder
>(t
: token
::Token
, fld
: &mut T
) -> token
::Token
{
584 token
::Ident(id
, is_raw
) => token
::Ident(fld
.fold_ident(id
), is_raw
),
585 token
::Lifetime(id
) => token
::Lifetime(fld
.fold_ident(id
)),
586 token
::Interpolated(nt
) => {
587 let nt
= match Lrc
::try_unwrap(nt
) {
589 Err(nt
) => (*nt
).clone(),
591 Token
::interpolated(fld
.fold_interpolated(nt
.0))
597 /// apply folder to elements of interpolated nodes
599 // NB: this can occur only when applying a fold to partially expanded code, where
600 // parsed pieces have gotten implanted ito *other* macro invocations. This is relevant
601 // for macro hygiene, but possibly not elsewhere.
603 // One problem here occurs because the types for fold_item, fold_stmt, etc. allow the
604 // folder to return *multiple* items; this is a problem for the nodes here, because
605 // they insist on having exactly one piece. One solution would be to mangle the fold
606 // trait to include one-to-many and one-to-one versions of these entry points, but that
607 // would probably confuse a lot of people and help very few. Instead, I'm just going
608 // to put in dynamic checks. I think the performance impact of this will be pretty much
609 // nonexistent. The danger is that someone will apply a fold to a partially expanded
610 // node, and will be confused by the fact that their "fold_item" or "fold_stmt" isn't
611 // getting called on NtItem or NtStmt nodes. Hopefully they'll wind up reading this
612 // comment, and doing something appropriate.
614 // BTW, design choice: I considered just changing the type of, e.g., NtItem to contain
615 // multiple items, but decided against it when I looked at parse_item_or_view_item and
616 // tried to figure out what I would do with multiple items there....
617 pub fn noop_fold_interpolated
<T
: Folder
>(nt
: token
::Nonterminal
, fld
: &mut T
)
618 -> token
::Nonterminal
{
620 token
::NtItem(item
) =>
621 token
::NtItem(fld
.fold_item(item
)
622 // this is probably okay, because the only folds likely
623 // to peek inside interpolated nodes will be renamings/markings,
624 // which map single items to single items
625 .expect_one("expected fold to produce exactly one item")),
626 token
::NtBlock(block
) => token
::NtBlock(fld
.fold_block(block
)),
627 token
::NtStmt(stmt
) =>
628 token
::NtStmt(fld
.fold_stmt(stmt
)
629 // this is probably okay, because the only folds likely
630 // to peek inside interpolated nodes will be renamings/markings,
631 // which map single items to single items
632 .expect_one("expected fold to produce exactly one statement")),
633 token
::NtPat(pat
) => token
::NtPat(fld
.fold_pat(pat
)),
634 token
::NtExpr(expr
) => token
::NtExpr(fld
.fold_expr(expr
)),
635 token
::NtTy(ty
) => token
::NtTy(fld
.fold_ty(ty
)),
636 token
::NtIdent(ident
, is_raw
) => token
::NtIdent(fld
.fold_ident(ident
), is_raw
),
637 token
::NtLifetime(ident
) => token
::NtLifetime(fld
.fold_ident(ident
)),
638 token
::NtMeta(meta
) => token
::NtMeta(fld
.fold_meta_item(meta
)),
639 token
::NtPath(path
) => token
::NtPath(fld
.fold_path(path
)),
640 token
::NtTT(tt
) => token
::NtTT(fld
.fold_tt(tt
)),
641 token
::NtArm(arm
) => token
::NtArm(fld
.fold_arm(arm
)),
642 token
::NtImplItem(item
) =>
643 token
::NtImplItem(fld
.fold_impl_item(item
)
644 .expect_one("expected fold to produce exactly one item")),
645 token
::NtTraitItem(item
) =>
646 token
::NtTraitItem(fld
.fold_trait_item(item
)
647 .expect_one("expected fold to produce exactly one item")),
648 token
::NtGenerics(generics
) => token
::NtGenerics(fld
.fold_generics(generics
)),
649 token
::NtWhereClause(where_clause
) =>
650 token
::NtWhereClause(fld
.fold_where_clause(where_clause
)),
651 token
::NtArg(arg
) => token
::NtArg(fld
.fold_arg(arg
)),
652 token
::NtVis(vis
) => token
::NtVis(fld
.fold_vis(vis
)),
653 token
::NtForeignItem(ni
) =>
654 token
::NtForeignItem(fld
.fold_foreign_item(ni
)
655 // see reasoning above
656 .expect_one("expected fold to produce exactly one item")),
660 pub fn noop_fold_fn_decl
<T
: Folder
>(decl
: P
<FnDecl
>, fld
: &mut T
) -> P
<FnDecl
> {
661 decl
.map(|FnDecl {inputs, output, variadic}
| FnDecl
{
662 inputs
: inputs
.move_map(|x
| fld
.fold_arg(x
)),
663 output
: match output
{
664 FunctionRetTy
::Ty(ty
) => FunctionRetTy
::Ty(fld
.fold_ty(ty
)),
665 FunctionRetTy
::Default(span
) => FunctionRetTy
::Default(fld
.new_span(span
)),
671 pub fn noop_fold_ty_param_bound
<T
>(tpb
: TyParamBound
, fld
: &mut T
)
675 TraitTyParamBound(ty
, modifier
) => TraitTyParamBound(fld
.fold_poly_trait_ref(ty
), modifier
),
676 RegionTyParamBound(lifetime
) => RegionTyParamBound(fld
.fold_lifetime(lifetime
)),
680 pub fn noop_fold_ty_param
<T
: Folder
>(tp
: TyParam
, fld
: &mut T
) -> TyParam
{
681 let TyParam {attrs, id, ident, bounds, default}
= tp
;
682 let attrs
: Vec
<_
> = attrs
.into();
684 attrs
: attrs
.into_iter()
685 .flat_map(|x
| fld
.fold_attribute(x
).into_iter())
689 ident
: fld
.fold_ident(ident
),
690 bounds
: fld
.fold_bounds(bounds
),
691 default: default.map(|x
| fld
.fold_ty(x
)),
695 pub fn noop_fold_generic_param
<T
: Folder
>(param
: GenericParam
, fld
: &mut T
) -> GenericParam
{
697 GenericParam
::Lifetime(l
) => GenericParam
::Lifetime(fld
.fold_lifetime_def(l
)),
698 GenericParam
::Type(t
) => GenericParam
::Type(fld
.fold_ty_param(t
)),
702 pub fn noop_fold_generic_params
<T
: Folder
>(
703 params
: Vec
<GenericParam
>,
705 ) -> Vec
<GenericParam
> {
706 params
.move_map(|p
| fld
.fold_generic_param(p
))
709 pub fn noop_fold_label
<T
: Folder
>(label
: Label
, fld
: &mut T
) -> Label
{
711 ident
: fld
.fold_ident(label
.ident
),
715 pub fn noop_fold_lifetime
<T
: Folder
>(l
: Lifetime
, fld
: &mut T
) -> Lifetime
{
717 id
: fld
.new_id(l
.id
),
718 ident
: fld
.fold_ident(l
.ident
),
722 pub fn noop_fold_lifetime_def
<T
: Folder
>(l
: LifetimeDef
, fld
: &mut T
)
724 let attrs
: Vec
<_
> = l
.attrs
.into();
726 attrs
: attrs
.into_iter()
727 .flat_map(|x
| fld
.fold_attribute(x
).into_iter())
730 lifetime
: fld
.fold_lifetime(l
.lifetime
),
731 bounds
: fld
.fold_lifetimes(l
.bounds
),
735 pub fn noop_fold_lifetimes
<T
: Folder
>(lts
: Vec
<Lifetime
>, fld
: &mut T
) -> Vec
<Lifetime
> {
736 lts
.move_map(|l
| fld
.fold_lifetime(l
))
739 pub fn noop_fold_lifetime_defs
<T
: Folder
>(lts
: Vec
<LifetimeDef
>, fld
: &mut T
)
740 -> Vec
<LifetimeDef
> {
741 lts
.move_map(|l
| fld
.fold_lifetime_def(l
))
744 pub fn noop_fold_opt_lifetime
<T
: Folder
>(o_lt
: Option
<Lifetime
>, fld
: &mut T
)
745 -> Option
<Lifetime
> {
746 o_lt
.map(|lt
| fld
.fold_lifetime(lt
))
749 pub fn noop_fold_generics
<T
: Folder
>(Generics { params, where_clause, span }
: Generics
,
750 fld
: &mut T
) -> Generics
{
752 params
: fld
.fold_generic_params(params
),
753 where_clause
: fld
.fold_where_clause(where_clause
),
754 span
: fld
.new_span(span
),
758 pub fn noop_fold_where_clause
<T
: Folder
>(
759 WhereClause {id, predicates, span}
: WhereClause
,
764 predicates
: predicates
.move_map(|predicate
| {
765 fld
.fold_where_predicate(predicate
)
771 pub fn noop_fold_where_predicate
<T
: Folder
>(
772 pred
: WherePredicate
,
776 ast
::WherePredicate
::BoundPredicate(ast
::WhereBoundPredicate
{bound_generic_params
,
780 ast
::WherePredicate
::BoundPredicate(ast
::WhereBoundPredicate
{
781 bound_generic_params
: fld
.fold_generic_params(bound_generic_params
),
782 bounded_ty
: fld
.fold_ty(bounded_ty
),
783 bounds
: bounds
.move_map(|x
| fld
.fold_ty_param_bound(x
)),
784 span
: fld
.new_span(span
)
787 ast
::WherePredicate
::RegionPredicate(ast
::WhereRegionPredicate
{lifetime
,
790 ast
::WherePredicate
::RegionPredicate(ast
::WhereRegionPredicate
{
791 span
: fld
.new_span(span
),
792 lifetime
: fld
.fold_lifetime(lifetime
),
793 bounds
: bounds
.move_map(|bound
| fld
.fold_lifetime(bound
))
796 ast
::WherePredicate
::EqPredicate(ast
::WhereEqPredicate
{id
,
800 ast
::WherePredicate
::EqPredicate(ast
::WhereEqPredicate
{
802 lhs_ty
: fld
.fold_ty(lhs_ty
),
803 rhs_ty
: fld
.fold_ty(rhs_ty
),
804 span
: fld
.new_span(span
)
810 pub fn noop_fold_variant_data
<T
: Folder
>(vdata
: VariantData
, fld
: &mut T
) -> VariantData
{
812 ast
::VariantData
::Struct(fields
, id
) => {
813 ast
::VariantData
::Struct(fields
.move_map(|f
| fld
.fold_struct_field(f
)),
816 ast
::VariantData
::Tuple(fields
, id
) => {
817 ast
::VariantData
::Tuple(fields
.move_map(|f
| fld
.fold_struct_field(f
)),
820 ast
::VariantData
::Unit(id
) => ast
::VariantData
::Unit(fld
.new_id(id
))
824 pub fn noop_fold_trait_ref
<T
: Folder
>(p
: TraitRef
, fld
: &mut T
) -> TraitRef
{
825 let id
= fld
.new_id(p
.ref_id
);
831 path
: fld
.fold_path(path
),
836 pub fn noop_fold_poly_trait_ref
<T
: Folder
>(p
: PolyTraitRef
, fld
: &mut T
) -> PolyTraitRef
{
838 bound_generic_params
: fld
.fold_generic_params(p
.bound_generic_params
),
839 trait_ref
: fld
.fold_trait_ref(p
.trait_ref
),
840 span
: fld
.new_span(p
.span
),
844 pub fn noop_fold_struct_field
<T
: Folder
>(f
: StructField
, fld
: &mut T
) -> StructField
{
846 span
: fld
.new_span(f
.span
),
847 id
: fld
.new_id(f
.id
),
848 ident
: f
.ident
.map(|ident
| fld
.fold_ident(ident
)),
849 vis
: fld
.fold_vis(f
.vis
),
850 ty
: fld
.fold_ty(f
.ty
),
851 attrs
: fold_attrs(f
.attrs
, fld
),
855 pub fn noop_fold_field
<T
: Folder
>(f
: Field
, folder
: &mut T
) -> Field
{
857 ident
: folder
.fold_ident(f
.ident
),
858 expr
: folder
.fold_expr(f
.expr
),
859 span
: folder
.new_span(f
.span
),
860 is_shorthand
: f
.is_shorthand
,
861 attrs
: fold_thin_attrs(f
.attrs
, folder
),
865 pub fn noop_fold_mt
<T
: Folder
>(MutTy {ty, mutbl}
: MutTy
, folder
: &mut T
) -> MutTy
{
867 ty
: folder
.fold_ty(ty
),
872 pub fn noop_fold_opt_bounds
<T
: Folder
>(b
: Option
<TyParamBounds
>, folder
: &mut T
)
873 -> Option
<TyParamBounds
> {
874 b
.map(|bounds
| folder
.fold_bounds(bounds
))
877 fn noop_fold_bounds
<T
: Folder
>(bounds
: TyParamBounds
, folder
: &mut T
)
879 bounds
.move_map(|bound
| folder
.fold_ty_param_bound(bound
))
882 pub fn noop_fold_block
<T
: Folder
>(b
: P
<Block
>, folder
: &mut T
) -> P
<Block
> {
883 b
.map(|Block {id, stmts, rules, span, recovered}
| Block
{
884 id
: folder
.new_id(id
),
885 stmts
: stmts
.move_flat_map(|s
| folder
.fold_stmt(s
).into_iter()),
887 span
: folder
.new_span(span
),
892 pub fn noop_fold_item_kind
<T
: Folder
>(i
: ItemKind
, folder
: &mut T
) -> ItemKind
{
894 ItemKind
::ExternCrate(orig_name
) => ItemKind
::ExternCrate(orig_name
),
895 ItemKind
::Use(use_tree
) => {
896 ItemKind
::Use(use_tree
.map(|tree
| folder
.fold_use_tree(tree
)))
898 ItemKind
::Static(t
, m
, e
) => {
899 ItemKind
::Static(folder
.fold_ty(t
), m
, folder
.fold_expr(e
))
901 ItemKind
::Const(t
, e
) => {
902 ItemKind
::Const(folder
.fold_ty(t
), folder
.fold_expr(e
))
904 ItemKind
::Fn(decl
, unsafety
, constness
, abi
, generics
, body
) => {
905 let generics
= folder
.fold_generics(generics
);
906 let decl
= folder
.fold_fn_decl(decl
);
907 let body
= folder
.fold_block(body
);
908 ItemKind
::Fn(decl
, unsafety
, constness
, abi
, generics
, body
)
910 ItemKind
::Mod(m
) => ItemKind
::Mod(folder
.fold_mod(m
)),
911 ItemKind
::ForeignMod(nm
) => ItemKind
::ForeignMod(folder
.fold_foreign_mod(nm
)),
912 ItemKind
::GlobalAsm(ga
) => ItemKind
::GlobalAsm(folder
.fold_global_asm(ga
)),
913 ItemKind
::Ty(t
, generics
) => {
914 ItemKind
::Ty(folder
.fold_ty(t
), folder
.fold_generics(generics
))
916 ItemKind
::Enum(enum_definition
, generics
) => {
917 let generics
= folder
.fold_generics(generics
);
918 let variants
= enum_definition
.variants
.move_map(|x
| folder
.fold_variant(x
));
919 ItemKind
::Enum(ast
::EnumDef { variants: variants }
, generics
)
921 ItemKind
::Struct(struct_def
, generics
) => {
922 let generics
= folder
.fold_generics(generics
);
923 ItemKind
::Struct(folder
.fold_variant_data(struct_def
), generics
)
925 ItemKind
::Union(struct_def
, generics
) => {
926 let generics
= folder
.fold_generics(generics
);
927 ItemKind
::Union(folder
.fold_variant_data(struct_def
), generics
)
929 ItemKind
::Impl(unsafety
,
935 impl_items
) => ItemKind
::Impl(
939 folder
.fold_generics(generics
),
940 ifce
.map(|trait_ref
| folder
.fold_trait_ref(trait_ref
.clone())),
942 impl_items
.move_flat_map(|item
| folder
.fold_impl_item(item
)),
944 ItemKind
::Trait(is_auto
, unsafety
, generics
, bounds
, items
) => ItemKind
::Trait(
947 folder
.fold_generics(generics
),
948 folder
.fold_bounds(bounds
),
949 items
.move_flat_map(|item
| folder
.fold_trait_item(item
)),
951 ItemKind
::TraitAlias(generics
, bounds
) => ItemKind
::TraitAlias(
952 folder
.fold_generics(generics
),
953 folder
.fold_bounds(bounds
)),
954 ItemKind
::Mac(m
) => ItemKind
::Mac(folder
.fold_mac(m
)),
955 ItemKind
::MacroDef(def
) => ItemKind
::MacroDef(folder
.fold_macro_def(def
)),
959 pub fn noop_fold_trait_item
<T
: Folder
>(i
: TraitItem
, folder
: &mut T
)
960 -> SmallVector
<TraitItem
> {
961 SmallVector
::one(TraitItem
{
962 id
: folder
.new_id(i
.id
),
963 ident
: folder
.fold_ident(i
.ident
),
964 attrs
: fold_attrs(i
.attrs
, folder
),
965 generics
: folder
.fold_generics(i
.generics
),
967 TraitItemKind
::Const(ty
, default) => {
968 TraitItemKind
::Const(folder
.fold_ty(ty
),
969 default.map(|x
| folder
.fold_expr(x
)))
971 TraitItemKind
::Method(sig
, body
) => {
972 TraitItemKind
::Method(noop_fold_method_sig(sig
, folder
),
973 body
.map(|x
| folder
.fold_block(x
)))
975 TraitItemKind
::Type(bounds
, default) => {
976 TraitItemKind
::Type(folder
.fold_bounds(bounds
),
977 default.map(|x
| folder
.fold_ty(x
)))
979 ast
::TraitItemKind
::Macro(mac
) => {
980 TraitItemKind
::Macro(folder
.fold_mac(mac
))
983 span
: folder
.new_span(i
.span
),
988 pub fn noop_fold_impl_item
<T
: Folder
>(i
: ImplItem
, folder
: &mut T
)
989 -> SmallVector
<ImplItem
> {
990 SmallVector
::one(ImplItem
{
991 id
: folder
.new_id(i
.id
),
992 vis
: folder
.fold_vis(i
.vis
),
993 ident
: folder
.fold_ident(i
.ident
),
994 attrs
: fold_attrs(i
.attrs
, folder
),
995 generics
: folder
.fold_generics(i
.generics
),
996 defaultness
: i
.defaultness
,
998 ast
::ImplItemKind
::Const(ty
, expr
) => {
999 ast
::ImplItemKind
::Const(folder
.fold_ty(ty
), folder
.fold_expr(expr
))
1001 ast
::ImplItemKind
::Method(sig
, body
) => {
1002 ast
::ImplItemKind
::Method(noop_fold_method_sig(sig
, folder
),
1003 folder
.fold_block(body
))
1005 ast
::ImplItemKind
::Type(ty
) => ast
::ImplItemKind
::Type(folder
.fold_ty(ty
)),
1006 ast
::ImplItemKind
::Macro(mac
) => ast
::ImplItemKind
::Macro(folder
.fold_mac(mac
))
1008 span
: folder
.new_span(i
.span
),
1013 pub fn noop_fold_mod
<T
: Folder
>(Mod {inner, items}
: Mod
, folder
: &mut T
) -> Mod
{
1015 inner
: folder
.new_span(inner
),
1016 items
: items
.move_flat_map(|x
| folder
.fold_item(x
)),
1020 pub fn noop_fold_crate
<T
: Folder
>(Crate {module, attrs, span}
: Crate
,
1021 folder
: &mut T
) -> Crate
{
1022 let mut items
= folder
.fold_item(P(ast
::Item
{
1023 ident
: keywords
::Invalid
.ident(),
1025 id
: ast
::DUMMY_NODE_ID
,
1026 vis
: respan(span
.shrink_to_lo(), ast
::VisibilityKind
::Public
),
1028 node
: ast
::ItemKind
::Mod(module
),
1032 let (module
, attrs
, span
) = match items
.next() {
1034 assert
!(items
.next().is_none(),
1035 "a crate cannot expand to more than one item");
1036 item
.and_then(|ast
::Item { attrs, span, node, .. }
| {
1038 ast
::ItemKind
::Mod(m
) => (m
, attrs
, span
),
1039 _
=> panic
!("fold converted a module to not a module"),
1056 // fold one item into possibly many items
1057 pub fn noop_fold_item
<T
: Folder
>(i
: P
<Item
>, folder
: &mut T
) -> SmallVector
<P
<Item
>> {
1058 SmallVector
::one(i
.map(|i
| folder
.fold_item_simple(i
)))
1061 // fold one item into exactly one item
1062 pub fn noop_fold_item_simple
<T
: Folder
>(Item {id, ident, attrs, node, vis, span, tokens}
: Item
,
1063 folder
: &mut T
) -> Item
{
1065 id
: folder
.new_id(id
),
1066 vis
: folder
.fold_vis(vis
),
1067 ident
: folder
.fold_ident(ident
),
1068 attrs
: fold_attrs(attrs
, folder
),
1069 node
: folder
.fold_item_kind(node
),
1070 span
: folder
.new_span(span
),
1072 // FIXME: if this is replaced with a call to `folder.fold_tts` it causes
1073 // an ICE during resolve... odd!
1078 pub fn noop_fold_foreign_item
<T
: Folder
>(ni
: ForeignItem
, folder
: &mut T
)
1079 -> SmallVector
<ForeignItem
> {
1080 SmallVector
::one(folder
.fold_foreign_item_simple(ni
))
1083 pub fn noop_fold_foreign_item_simple
<T
: Folder
>(ni
: ForeignItem
, folder
: &mut T
) -> ForeignItem
{
1085 id
: folder
.new_id(ni
.id
),
1086 vis
: folder
.fold_vis(ni
.vis
),
1087 ident
: folder
.fold_ident(ni
.ident
),
1088 attrs
: fold_attrs(ni
.attrs
, folder
),
1089 node
: match ni
.node
{
1090 ForeignItemKind
::Fn(fdec
, generics
) => {
1091 ForeignItemKind
::Fn(folder
.fold_fn_decl(fdec
), folder
.fold_generics(generics
))
1093 ForeignItemKind
::Static(t
, m
) => {
1094 ForeignItemKind
::Static(folder
.fold_ty(t
), m
)
1096 ForeignItemKind
::Ty
=> ForeignItemKind
::Ty
,
1097 ForeignItemKind
::Macro(mac
) => ForeignItemKind
::Macro(folder
.fold_mac(mac
)),
1099 span
: folder
.new_span(ni
.span
)
1103 pub fn noop_fold_method_sig
<T
: Folder
>(sig
: MethodSig
, folder
: &mut T
) -> MethodSig
{
1106 unsafety
: sig
.unsafety
,
1107 constness
: sig
.constness
,
1108 decl
: folder
.fold_fn_decl(sig
.decl
)
1112 pub fn noop_fold_pat
<T
: Folder
>(p
: P
<Pat
>, folder
: &mut T
) -> P
<Pat
> {
1113 p
.map(|Pat {id, node, span}
| Pat
{
1114 id
: folder
.new_id(id
),
1116 PatKind
::Wild
=> PatKind
::Wild
,
1117 PatKind
::Ident(binding_mode
, ident
, sub
) => {
1118 PatKind
::Ident(binding_mode
,
1119 folder
.fold_ident(ident
),
1120 sub
.map(|x
| folder
.fold_pat(x
)))
1122 PatKind
::Lit(e
) => PatKind
::Lit(folder
.fold_expr(e
)),
1123 PatKind
::TupleStruct(pth
, pats
, ddpos
) => {
1124 PatKind
::TupleStruct(folder
.fold_path(pth
),
1125 pats
.move_map(|x
| folder
.fold_pat(x
)), ddpos
)
1127 PatKind
::Path(opt_qself
, pth
) => {
1128 let opt_qself
= opt_qself
.map(|qself
| {
1129 QSelf { ty: folder.fold_ty(qself.ty), position: qself.position }
1131 PatKind
::Path(opt_qself
, folder
.fold_path(pth
))
1133 PatKind
::Struct(pth
, fields
, etc
) => {
1134 let pth
= folder
.fold_path(pth
);
1135 let fs
= fields
.move_map(|f
| {
1136 Spanned
{ span
: folder
.new_span(f
.span
),
1137 node
: ast
::FieldPat
{
1138 ident
: folder
.fold_ident(f
.node
.ident
),
1139 pat
: folder
.fold_pat(f
.node
.pat
),
1140 is_shorthand
: f
.node
.is_shorthand
,
1141 attrs
: fold_attrs(f
.node
.attrs
.into(), folder
).into()
1144 PatKind
::Struct(pth
, fs
, etc
)
1146 PatKind
::Tuple(elts
, ddpos
) => {
1147 PatKind
::Tuple(elts
.move_map(|x
| folder
.fold_pat(x
)), ddpos
)
1149 PatKind
::Box(inner
) => PatKind
::Box(folder
.fold_pat(inner
)),
1150 PatKind
::Ref(inner
, mutbl
) => PatKind
::Ref(folder
.fold_pat(inner
), mutbl
),
1151 PatKind
::Range(e1
, e2
, end
) => {
1152 PatKind
::Range(folder
.fold_expr(e1
),
1153 folder
.fold_expr(e2
),
1154 folder
.fold_range_end(end
))
1156 PatKind
::Slice(before
, slice
, after
) => {
1157 PatKind
::Slice(before
.move_map(|x
| folder
.fold_pat(x
)),
1158 slice
.map(|x
| folder
.fold_pat(x
)),
1159 after
.move_map(|x
| folder
.fold_pat(x
)))
1161 PatKind
::Paren(inner
) => PatKind
::Paren(folder
.fold_pat(inner
)),
1162 PatKind
::Mac(mac
) => PatKind
::Mac(folder
.fold_mac(mac
))
1164 span
: folder
.new_span(span
)
1168 pub fn noop_fold_range_end
<T
: Folder
>(end
: RangeEnd
, _folder
: &mut T
) -> RangeEnd
{
1172 pub fn noop_fold_expr
<T
: Folder
>(Expr {id, node, span, attrs}
: Expr
, folder
: &mut T
) -> Expr
{
1175 ExprKind
::Box(e
) => {
1176 ExprKind
::Box(folder
.fold_expr(e
))
1178 ExprKind
::ObsoleteInPlace(a
, b
) => {
1179 ExprKind
::ObsoleteInPlace(folder
.fold_expr(a
), folder
.fold_expr(b
))
1181 ExprKind
::Array(exprs
) => {
1182 ExprKind
::Array(folder
.fold_exprs(exprs
))
1184 ExprKind
::Repeat(expr
, count
) => {
1185 ExprKind
::Repeat(folder
.fold_expr(expr
), folder
.fold_expr(count
))
1187 ExprKind
::Tup(exprs
) => ExprKind
::Tup(folder
.fold_exprs(exprs
)),
1188 ExprKind
::Call(f
, args
) => {
1189 ExprKind
::Call(folder
.fold_expr(f
),
1190 folder
.fold_exprs(args
))
1192 ExprKind
::MethodCall(seg
, args
) => {
1193 ExprKind
::MethodCall(
1195 ident
: folder
.fold_ident(seg
.ident
),
1196 parameters
: seg
.parameters
.map(|ps
| {
1197 ps
.map(|ps
| folder
.fold_path_parameters(ps
))
1200 folder
.fold_exprs(args
))
1202 ExprKind
::Binary(binop
, lhs
, rhs
) => {
1203 ExprKind
::Binary(binop
,
1204 folder
.fold_expr(lhs
),
1205 folder
.fold_expr(rhs
))
1207 ExprKind
::Unary(binop
, ohs
) => {
1208 ExprKind
::Unary(binop
, folder
.fold_expr(ohs
))
1210 ExprKind
::Lit(l
) => ExprKind
::Lit(l
),
1211 ExprKind
::Cast(expr
, ty
) => {
1212 ExprKind
::Cast(folder
.fold_expr(expr
), folder
.fold_ty(ty
))
1214 ExprKind
::Type(expr
, ty
) => {
1215 ExprKind
::Type(folder
.fold_expr(expr
), folder
.fold_ty(ty
))
1217 ExprKind
::AddrOf(m
, ohs
) => ExprKind
::AddrOf(m
, folder
.fold_expr(ohs
)),
1218 ExprKind
::If(cond
, tr
, fl
) => {
1219 ExprKind
::If(folder
.fold_expr(cond
),
1220 folder
.fold_block(tr
),
1221 fl
.map(|x
| folder
.fold_expr(x
)))
1223 ExprKind
::IfLet(pats
, expr
, tr
, fl
) => {
1224 ExprKind
::IfLet(pats
.move_map(|pat
| folder
.fold_pat(pat
)),
1225 folder
.fold_expr(expr
),
1226 folder
.fold_block(tr
),
1227 fl
.map(|x
| folder
.fold_expr(x
)))
1229 ExprKind
::While(cond
, body
, opt_label
) => {
1230 ExprKind
::While(folder
.fold_expr(cond
),
1231 folder
.fold_block(body
),
1232 opt_label
.map(|label
| folder
.fold_label(label
)))
1234 ExprKind
::WhileLet(pats
, expr
, body
, opt_label
) => {
1235 ExprKind
::WhileLet(pats
.move_map(|pat
| folder
.fold_pat(pat
)),
1236 folder
.fold_expr(expr
),
1237 folder
.fold_block(body
),
1238 opt_label
.map(|label
| folder
.fold_label(label
)))
1240 ExprKind
::ForLoop(pat
, iter
, body
, opt_label
) => {
1241 ExprKind
::ForLoop(folder
.fold_pat(pat
),
1242 folder
.fold_expr(iter
),
1243 folder
.fold_block(body
),
1244 opt_label
.map(|label
| folder
.fold_label(label
)))
1246 ExprKind
::Loop(body
, opt_label
) => {
1247 ExprKind
::Loop(folder
.fold_block(body
),
1248 opt_label
.map(|label
| folder
.fold_label(label
)))
1250 ExprKind
::Match(expr
, arms
) => {
1251 ExprKind
::Match(folder
.fold_expr(expr
),
1252 arms
.move_map(|x
| folder
.fold_arm(x
)))
1254 ExprKind
::Closure(capture_clause
, movability
, decl
, body
, span
) => {
1255 ExprKind
::Closure(capture_clause
,
1257 folder
.fold_fn_decl(decl
),
1258 folder
.fold_expr(body
),
1259 folder
.new_span(span
))
1261 ExprKind
::Block(blk
) => ExprKind
::Block(folder
.fold_block(blk
)),
1262 ExprKind
::Assign(el
, er
) => {
1263 ExprKind
::Assign(folder
.fold_expr(el
), folder
.fold_expr(er
))
1265 ExprKind
::AssignOp(op
, el
, er
) => {
1266 ExprKind
::AssignOp(op
,
1267 folder
.fold_expr(el
),
1268 folder
.fold_expr(er
))
1270 ExprKind
::Field(el
, ident
) => {
1271 ExprKind
::Field(folder
.fold_expr(el
), folder
.fold_ident(ident
))
1273 ExprKind
::Index(el
, er
) => {
1274 ExprKind
::Index(folder
.fold_expr(el
), folder
.fold_expr(er
))
1276 ExprKind
::Range(e1
, e2
, lim
) => {
1277 ExprKind
::Range(e1
.map(|x
| folder
.fold_expr(x
)),
1278 e2
.map(|x
| folder
.fold_expr(x
)),
1281 ExprKind
::Path(qself
, path
) => {
1282 let qself
= qself
.map(|QSelf { ty, position }
| {
1284 ty
: folder
.fold_ty(ty
),
1288 ExprKind
::Path(qself
, folder
.fold_path(path
))
1290 ExprKind
::Break(opt_label
, opt_expr
) => {
1291 ExprKind
::Break(opt_label
.map(|label
| folder
.fold_label(label
)),
1292 opt_expr
.map(|e
| folder
.fold_expr(e
)))
1294 ExprKind
::Continue(opt_label
) => {
1295 ExprKind
::Continue(opt_label
.map(|label
| folder
.fold_label(label
)))
1297 ExprKind
::Ret(e
) => ExprKind
::Ret(e
.map(|x
| folder
.fold_expr(x
))),
1298 ExprKind
::InlineAsm(asm
) => ExprKind
::InlineAsm(asm
.map(|asm
| {
1300 inputs
: asm
.inputs
.move_map(|(c
, input
)| {
1301 (c
, folder
.fold_expr(input
))
1303 outputs
: asm
.outputs
.move_map(|out
| {
1305 constraint
: out
.constraint
,
1306 expr
: folder
.fold_expr(out
.expr
),
1308 is_indirect
: out
.is_indirect
,
1314 ExprKind
::Mac(mac
) => ExprKind
::Mac(folder
.fold_mac(mac
)),
1315 ExprKind
::Struct(path
, fields
, maybe_expr
) => {
1316 ExprKind
::Struct(folder
.fold_path(path
),
1317 fields
.move_map(|x
| folder
.fold_field(x
)),
1318 maybe_expr
.map(|x
| folder
.fold_expr(x
)))
1320 ExprKind
::Paren(ex
) => {
1321 let sub_expr
= folder
.fold_expr(ex
);
1323 // Nodes that are equal modulo `Paren` sugar no-ops should have the same ids.
1325 node
: ExprKind
::Paren(sub_expr
),
1326 span
: folder
.new_span(span
),
1327 attrs
: fold_attrs(attrs
.into(), folder
).into(),
1330 ExprKind
::Yield(ex
) => ExprKind
::Yield(ex
.map(|x
| folder
.fold_expr(x
))),
1331 ExprKind
::Try(ex
) => ExprKind
::Try(folder
.fold_expr(ex
)),
1332 ExprKind
::Catch(body
) => ExprKind
::Catch(folder
.fold_block(body
)),
1334 id
: folder
.new_id(id
),
1335 span
: folder
.new_span(span
),
1336 attrs
: fold_attrs(attrs
.into(), folder
).into(),
1340 pub fn noop_fold_opt_expr
<T
: Folder
>(e
: P
<Expr
>, folder
: &mut T
) -> Option
<P
<Expr
>> {
1341 Some(folder
.fold_expr(e
))
1344 pub fn noop_fold_exprs
<T
: Folder
>(es
: Vec
<P
<Expr
>>, folder
: &mut T
) -> Vec
<P
<Expr
>> {
1345 es
.move_flat_map(|e
| folder
.fold_opt_expr(e
))
1348 pub fn noop_fold_stmt
<T
: Folder
>(Stmt {node, span, id}
: Stmt
, folder
: &mut T
) -> SmallVector
<Stmt
> {
1349 let id
= folder
.new_id(id
);
1350 let span
= folder
.new_span(span
);
1351 noop_fold_stmt_kind(node
, folder
).into_iter().map(|node
| {
1352 Stmt { id: id, node: node, span: span }
1356 pub fn noop_fold_stmt_kind
<T
: Folder
>(node
: StmtKind
, folder
: &mut T
) -> SmallVector
<StmtKind
> {
1358 StmtKind
::Local(local
) => SmallVector
::one(StmtKind
::Local(folder
.fold_local(local
))),
1359 StmtKind
::Item(item
) => folder
.fold_item(item
).into_iter().map(StmtKind
::Item
).collect(),
1360 StmtKind
::Expr(expr
) => {
1361 folder
.fold_opt_expr(expr
).into_iter().map(StmtKind
::Expr
).collect()
1363 StmtKind
::Semi(expr
) => {
1364 folder
.fold_opt_expr(expr
).into_iter().map(StmtKind
::Semi
).collect()
1366 StmtKind
::Mac(mac
) => SmallVector
::one(StmtKind
::Mac(mac
.map(|(mac
, semi
, attrs
)| {
1367 (folder
.fold_mac(mac
), semi
, fold_attrs(attrs
.into(), folder
).into())
1372 pub fn noop_fold_vis
<T
: Folder
>(vis
: Visibility
, folder
: &mut T
) -> Visibility
{
1374 VisibilityKind
::Restricted { path, id }
=> {
1375 respan(vis
.span
, VisibilityKind
::Restricted
{
1376 path
: path
.map(|path
| folder
.fold_path(path
)),
1377 id
: folder
.new_id(id
),
1387 use ast
::{self, Ident}
;
1388 use util
::parser_testing
::{string_to_crate, matches_codepattern}
;
1394 // this version doesn't care about getting comments or docstrings in.
1395 fn fake_print_crate(s
: &mut pprust
::State
,
1396 krate
: &ast
::Crate
) -> io
::Result
<()> {
1397 s
.print_mod(&krate
.module
, &krate
.attrs
)
1400 // change every identifier to "zz"
1401 struct ToZzIdentFolder
;
1403 impl Folder
for ToZzIdentFolder
{
1404 fn fold_ident(&mut self, _
: ast
::Ident
) -> ast
::Ident
{
1405 Ident
::from_str("zz")
1407 fn fold_mac(&mut self, mac
: ast
::Mac
) -> ast
::Mac
{
1408 fold
::noop_fold_mac(mac
, self)
1412 // maybe add to expand.rs...
1413 macro_rules
! assert_pred
{
1414 ($pred
:expr
, $predname
:expr
, $a
:expr
, $b
:expr
) => (
1416 let pred_val
= $pred
;
1419 if !(pred_val(&a_val
, &b_val
)) {
1420 panic
!("expected args satisfying {}, got {} and {}",
1421 $predname
, a_val
, b_val
);
1427 // make sure idents get transformed everywhere
1428 #[test] fn ident_transformation () {
1430 let mut zz_fold
= ToZzIdentFolder
;
1431 let ast
= string_to_crate(
1432 "#[a] mod b {fn c (d : e, f : g) {h!(i,j,k);l;m}}".to_string());
1433 let folded_crate
= zz_fold
.fold_crate(ast
);
1435 matches_codepattern
,
1436 "matches_codepattern",
1437 pprust
::to_string(|s
| fake_print_crate(s
, &folded_crate
)),
1438 "#[zz]mod zz{fn zz(zz:zz,zz:zz){zz!(zz,zz,zz);zz;zz}}".to_string());
1442 // even inside macro defs....
1443 #[test] fn ident_transformation_in_defs () {
1445 let mut zz_fold
= ToZzIdentFolder
;
1446 let ast
= string_to_crate(
1447 "macro_rules! a {(b $c:expr $(d $e:token)f+ => \
1448 (g $(d $d $e)+))} ".to_string());
1449 let folded_crate
= zz_fold
.fold_crate(ast
);
1451 matches_codepattern
,
1452 "matches_codepattern",
1453 pprust
::to_string(|s
| fake_print_crate(s
, &folded_crate
)),
1454 "macro_rules! zz((zz$zz:zz$(zz $zz:zz)zz+=>(zz$(zz$zz$zz)+)));".to_string());