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
;
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_view_path(&mut self, view_path
: P
<ViewPath
>) -> P
<ViewPath
> {
60 noop_fold_view_path(view_path
, self)
63 fn fold_foreign_item(&mut self, ni
: ForeignItem
) -> ForeignItem
{
64 noop_fold_foreign_item(ni
, self)
67 fn fold_item(&mut self, i
: P
<Item
>) -> SmallVector
<P
<Item
>> {
68 noop_fold_item(i
, self)
71 fn fold_item_simple(&mut self, i
: Item
) -> Item
{
72 noop_fold_item_simple(i
, self)
75 fn fold_struct_field(&mut self, sf
: StructField
) -> StructField
{
76 noop_fold_struct_field(sf
, self)
79 fn fold_item_kind(&mut self, i
: ItemKind
) -> ItemKind
{
80 noop_fold_item_kind(i
, self)
83 fn fold_trait_item(&mut self, i
: TraitItem
) -> SmallVector
<TraitItem
> {
84 noop_fold_trait_item(i
, self)
87 fn fold_impl_item(&mut self, i
: ImplItem
) -> SmallVector
<ImplItem
> {
88 noop_fold_impl_item(i
, self)
91 fn fold_fn_decl(&mut self, d
: P
<FnDecl
>) -> P
<FnDecl
> {
92 noop_fold_fn_decl(d
, self)
95 fn fold_block(&mut self, b
: P
<Block
>) -> P
<Block
> {
96 noop_fold_block(b
, self)
99 fn fold_stmt(&mut self, s
: Stmt
) -> SmallVector
<Stmt
> {
100 noop_fold_stmt(s
, self)
103 fn fold_arm(&mut self, a
: Arm
) -> Arm
{
104 noop_fold_arm(a
, self)
107 fn fold_pat(&mut self, p
: P
<Pat
>) -> P
<Pat
> {
108 noop_fold_pat(p
, self)
111 fn fold_expr(&mut self, e
: P
<Expr
>) -> P
<Expr
> {
112 e
.map(|e
| noop_fold_expr(e
, self))
115 fn fold_range_end(&mut self, re
: RangeEnd
) -> RangeEnd
{
116 noop_fold_range_end(re
, self)
119 fn fold_opt_expr(&mut self, e
: P
<Expr
>) -> Option
<P
<Expr
>> {
120 noop_fold_opt_expr(e
, self)
123 fn fold_exprs(&mut self, es
: Vec
<P
<Expr
>>) -> Vec
<P
<Expr
>> {
124 noop_fold_exprs(es
, self)
127 fn fold_ty(&mut self, t
: P
<Ty
>) -> P
<Ty
> {
128 noop_fold_ty(t
, self)
131 fn fold_ty_binding(&mut self, t
: TypeBinding
) -> TypeBinding
{
132 noop_fold_ty_binding(t
, self)
135 fn fold_mod(&mut self, m
: Mod
) -> Mod
{
136 noop_fold_mod(m
, self)
139 fn fold_foreign_mod(&mut self, nm
: ForeignMod
) -> ForeignMod
{
140 noop_fold_foreign_mod(nm
, self)
143 fn fold_global_asm(&mut self, ga
: P
<GlobalAsm
>) -> P
<GlobalAsm
> {
144 noop_fold_global_asm(ga
, self)
147 fn fold_variant(&mut self, v
: Variant
) -> Variant
{
148 noop_fold_variant(v
, self)
151 fn fold_ident(&mut self, i
: Ident
) -> Ident
{
152 noop_fold_ident(i
, self)
155 fn fold_usize(&mut self, i
: usize) -> usize {
156 noop_fold_usize(i
, self)
159 fn fold_path(&mut self, p
: Path
) -> Path
{
160 noop_fold_path(p
, self)
163 fn fold_path_parameters(&mut self, p
: PathParameters
) -> PathParameters
{
164 noop_fold_path_parameters(p
, self)
167 fn fold_angle_bracketed_parameter_data(&mut self, p
: AngleBracketedParameterData
)
168 -> AngleBracketedParameterData
170 noop_fold_angle_bracketed_parameter_data(p
, self)
173 fn fold_parenthesized_parameter_data(&mut self, p
: ParenthesizedParameterData
)
174 -> ParenthesizedParameterData
176 noop_fold_parenthesized_parameter_data(p
, self)
179 fn fold_local(&mut self, l
: P
<Local
>) -> P
<Local
> {
180 noop_fold_local(l
, self)
183 fn fold_mac(&mut self, _mac
: Mac
) -> Mac
{
184 panic
!("fold_mac disabled by default");
185 // NB: see note about macros above.
186 // if you really want a folder that
187 // works on macros, use this
188 // definition in your trait impl:
189 // fold::noop_fold_mac(_mac, self)
192 fn fold_macro_def(&mut self, def
: MacroDef
) -> MacroDef
{
193 noop_fold_macro_def(def
, self)
196 fn fold_lifetime(&mut self, l
: Lifetime
) -> Lifetime
{
197 noop_fold_lifetime(l
, self)
200 fn fold_lifetime_def(&mut self, l
: LifetimeDef
) -> LifetimeDef
{
201 noop_fold_lifetime_def(l
, self)
204 fn fold_attribute(&mut self, at
: Attribute
) -> Option
<Attribute
> {
205 noop_fold_attribute(at
, self)
208 fn fold_arg(&mut self, a
: Arg
) -> Arg
{
209 noop_fold_arg(a
, self)
212 fn fold_generics(&mut self, generics
: Generics
) -> Generics
{
213 noop_fold_generics(generics
, self)
216 fn fold_trait_ref(&mut self, p
: TraitRef
) -> TraitRef
{
217 noop_fold_trait_ref(p
, self)
220 fn fold_poly_trait_ref(&mut self, p
: PolyTraitRef
) -> PolyTraitRef
{
221 noop_fold_poly_trait_ref(p
, self)
224 fn fold_variant_data(&mut self, vdata
: VariantData
) -> VariantData
{
225 noop_fold_variant_data(vdata
, self)
228 fn fold_lifetimes(&mut self, lts
: Vec
<Lifetime
>) -> Vec
<Lifetime
> {
229 noop_fold_lifetimes(lts
, self)
232 fn fold_lifetime_defs(&mut self, lts
: Vec
<LifetimeDef
>) -> Vec
<LifetimeDef
> {
233 noop_fold_lifetime_defs(lts
, self)
236 fn fold_ty_param(&mut self, tp
: TyParam
) -> TyParam
{
237 noop_fold_ty_param(tp
, self)
240 fn fold_ty_params(&mut self, tps
: Vec
<TyParam
>) -> Vec
<TyParam
> {
241 noop_fold_ty_params(tps
, self)
244 fn fold_tt(&mut self, tt
: TokenTree
) -> TokenTree
{
245 noop_fold_tt(tt
, self)
248 fn fold_tts(&mut self, tts
: TokenStream
) -> TokenStream
{
249 noop_fold_tts(tts
, self)
252 fn fold_token(&mut self, t
: token
::Token
) -> token
::Token
{
253 noop_fold_token(t
, self)
256 fn fold_interpolated(&mut self, nt
: token
::Nonterminal
) -> token
::Nonterminal
{
257 noop_fold_interpolated(nt
, self)
260 fn fold_opt_lifetime(&mut self, o_lt
: Option
<Lifetime
>) -> Option
<Lifetime
> {
261 noop_fold_opt_lifetime(o_lt
, self)
264 fn fold_opt_bounds(&mut self, b
: Option
<TyParamBounds
>)
265 -> Option
<TyParamBounds
> {
266 noop_fold_opt_bounds(b
, self)
269 fn fold_bounds(&mut self, b
: TyParamBounds
)
271 noop_fold_bounds(b
, self)
274 fn fold_ty_param_bound(&mut self, tpb
: TyParamBound
) -> TyParamBound
{
275 noop_fold_ty_param_bound(tpb
, self)
278 fn fold_mt(&mut self, mt
: MutTy
) -> MutTy
{
279 noop_fold_mt(mt
, self)
282 fn fold_field(&mut self, field
: Field
) -> Field
{
283 noop_fold_field(field
, self)
286 fn fold_where_clause(&mut self, where_clause
: WhereClause
)
288 noop_fold_where_clause(where_clause
, self)
291 fn fold_where_predicate(&mut self, where_predicate
: WherePredicate
)
293 noop_fold_where_predicate(where_predicate
, self)
296 fn fold_vis(&mut self, vis
: Visibility
) -> Visibility
{
297 noop_fold_vis(vis
, self)
300 fn new_id(&mut self, i
: NodeId
) -> NodeId
{
304 fn new_span(&mut self, sp
: Span
) -> Span
{
309 pub fn noop_fold_meta_items
<T
: Folder
>(meta_items
: Vec
<MetaItem
>, fld
: &mut T
) -> Vec
<MetaItem
> {
310 meta_items
.move_map(|x
| fld
.fold_meta_item(x
))
313 pub fn noop_fold_view_path
<T
: Folder
>(view_path
: P
<ViewPath
>, fld
: &mut T
) -> P
<ViewPath
> {
314 view_path
.map(|Spanned {node, span}
| Spanned
{
316 ViewPathSimple(ident
, path
) => {
317 ViewPathSimple(fld
.fold_ident(ident
), fld
.fold_path(path
))
319 ViewPathGlob(path
) => {
320 ViewPathGlob(fld
.fold_path(path
))
322 ViewPathList(path
, path_list_idents
) => {
323 let path
= fld
.fold_path(path
);
324 let path_list_idents
= path_list_idents
.move_map(|path_list_ident
| Spanned
{
325 node
: PathListItem_
{
326 id
: fld
.new_id(path_list_ident
.node
.id
),
327 rename
: path_list_ident
.node
.rename
.map(|ident
| fld
.fold_ident(ident
)),
328 name
: fld
.fold_ident(path_list_ident
.node
.name
),
330 span
: fld
.new_span(path_list_ident
.span
)
332 ViewPathList(path
, path_list_idents
)
335 span
: fld
.new_span(span
)
339 pub fn fold_attrs
<T
: Folder
>(attrs
: Vec
<Attribute
>, fld
: &mut T
) -> Vec
<Attribute
> {
340 attrs
.move_flat_map(|x
| fld
.fold_attribute(x
))
343 pub fn fold_thin_attrs
<T
: Folder
>(attrs
: ThinVec
<Attribute
>, fld
: &mut T
) -> ThinVec
<Attribute
> {
344 fold_attrs(attrs
.into(), fld
).into()
347 pub fn noop_fold_arm
<T
: Folder
>(Arm {attrs, pats, guard, body}
: Arm
, fld
: &mut T
) -> Arm
{
349 attrs
: fold_attrs(attrs
, fld
),
350 pats
: pats
.move_map(|x
| fld
.fold_pat(x
)),
351 guard
: guard
.map(|x
| fld
.fold_expr(x
)),
352 body
: fld
.fold_expr(body
),
356 pub fn noop_fold_ty_binding
<T
: Folder
>(b
: TypeBinding
, fld
: &mut T
) -> TypeBinding
{
358 id
: fld
.new_id(b
.id
),
359 ident
: fld
.fold_ident(b
.ident
),
360 ty
: fld
.fold_ty(b
.ty
),
361 span
: fld
.new_span(b
.span
),
365 pub fn noop_fold_ty
<T
: Folder
>(t
: P
<Ty
>, fld
: &mut T
) -> P
<Ty
> {
366 t
.map(|Ty {id, node, span}
| Ty
{
369 TyKind
::Infer
| TyKind
::ImplicitSelf
| TyKind
::Err
=> node
,
370 TyKind
::Slice(ty
) => TyKind
::Slice(fld
.fold_ty(ty
)),
371 TyKind
::Ptr(mt
) => TyKind
::Ptr(fld
.fold_mt(mt
)),
372 TyKind
::Rptr(region
, mt
) => {
373 TyKind
::Rptr(fld
.fold_opt_lifetime(region
), fld
.fold_mt(mt
))
375 TyKind
::BareFn(f
) => {
376 TyKind
::BareFn(f
.map(|BareFnTy {lifetimes, unsafety, abi, decl}
| BareFnTy
{
377 lifetimes
: fld
.fold_lifetime_defs(lifetimes
),
380 decl
: fld
.fold_fn_decl(decl
)
383 TyKind
::Never
=> node
,
384 TyKind
::Tup(tys
) => TyKind
::Tup(tys
.move_map(|ty
| fld
.fold_ty(ty
))),
385 TyKind
::Paren(ty
) => TyKind
::Paren(fld
.fold_ty(ty
)),
386 TyKind
::Path(qself
, path
) => {
387 let qself
= qself
.map(|QSelf { ty, position }
| {
393 TyKind
::Path(qself
, fld
.fold_path(path
))
395 TyKind
::Array(ty
, e
) => {
396 TyKind
::Array(fld
.fold_ty(ty
), fld
.fold_expr(e
))
398 TyKind
::Typeof(expr
) => {
399 TyKind
::Typeof(fld
.fold_expr(expr
))
401 TyKind
::TraitObject(bounds
) => {
402 TyKind
::TraitObject(bounds
.move_map(|b
| fld
.fold_ty_param_bound(b
)))
404 TyKind
::ImplTrait(bounds
) => {
405 TyKind
::ImplTrait(bounds
.move_map(|b
| fld
.fold_ty_param_bound(b
)))
407 TyKind
::Mac(mac
) => {
408 TyKind
::Mac(fld
.fold_mac(mac
))
411 span
: fld
.new_span(span
)
415 pub fn noop_fold_foreign_mod
<T
: Folder
>(ForeignMod {abi, items}
: ForeignMod
,
416 fld
: &mut T
) -> ForeignMod
{
419 items
: items
.move_map(|x
| fld
.fold_foreign_item(x
)),
423 pub fn noop_fold_global_asm
<T
: Folder
>(ga
: P
<GlobalAsm
>,
424 _
: &mut T
) -> P
<GlobalAsm
> {
428 pub fn noop_fold_variant
<T
: Folder
>(v
: Variant
, fld
: &mut T
) -> Variant
{
431 name
: fld
.fold_ident(v
.node
.name
),
432 attrs
: fold_attrs(v
.node
.attrs
, fld
),
433 data
: fld
.fold_variant_data(v
.node
.data
),
434 disr_expr
: v
.node
.disr_expr
.map(|e
| fld
.fold_expr(e
)),
436 span
: fld
.new_span(v
.span
),
440 pub fn noop_fold_ident
<T
: Folder
>(i
: Ident
, _
: &mut T
) -> Ident
{
444 pub fn noop_fold_usize
<T
: Folder
>(i
: usize, _
: &mut T
) -> usize {
448 pub fn noop_fold_path
<T
: Folder
>(Path { segments, span }
: Path
, fld
: &mut T
) -> Path
{
450 segments
: segments
.move_map(|PathSegment {identifier, span, parameters}
| PathSegment
{
451 identifier
: fld
.fold_ident(identifier
),
452 span
: fld
.new_span(span
),
453 parameters
: parameters
.map(|ps
| ps
.map(|ps
| fld
.fold_path_parameters(ps
))),
455 span
: fld
.new_span(span
)
459 pub fn noop_fold_path_parameters
<T
: Folder
>(path_parameters
: PathParameters
, fld
: &mut T
)
462 match path_parameters
{
463 PathParameters
::AngleBracketed(data
) =>
464 PathParameters
::AngleBracketed(fld
.fold_angle_bracketed_parameter_data(data
)),
465 PathParameters
::Parenthesized(data
) =>
466 PathParameters
::Parenthesized(fld
.fold_parenthesized_parameter_data(data
)),
470 pub fn noop_fold_angle_bracketed_parameter_data
<T
: Folder
>(data
: AngleBracketedParameterData
,
472 -> AngleBracketedParameterData
474 let AngleBracketedParameterData { lifetimes, types, bindings, span }
= data
;
475 AngleBracketedParameterData
{ lifetimes
: fld
.fold_lifetimes(lifetimes
),
476 types
: types
.move_map(|ty
| fld
.fold_ty(ty
)),
477 bindings
: bindings
.move_map(|b
| fld
.fold_ty_binding(b
)),
478 span
: fld
.new_span(span
) }
481 pub fn noop_fold_parenthesized_parameter_data
<T
: Folder
>(data
: ParenthesizedParameterData
,
483 -> ParenthesizedParameterData
485 let ParenthesizedParameterData { inputs, output, span }
= data
;
486 ParenthesizedParameterData
{ inputs
: inputs
.move_map(|ty
| fld
.fold_ty(ty
)),
487 output
: output
.map(|ty
| fld
.fold_ty(ty
)),
488 span
: fld
.new_span(span
) }
491 pub fn noop_fold_local
<T
: Folder
>(l
: P
<Local
>, fld
: &mut T
) -> P
<Local
> {
492 l
.map(|Local {id, pat, ty, init, span, attrs}
| Local
{
494 pat
: fld
.fold_pat(pat
),
495 ty
: ty
.map(|t
| fld
.fold_ty(t
)),
496 init
: init
.map(|e
| fld
.fold_expr(e
)),
497 span
: fld
.new_span(span
),
498 attrs
: fold_attrs(attrs
.into(), fld
).into(),
502 pub fn noop_fold_attribute
<T
: Folder
>(attr
: Attribute
, fld
: &mut T
) -> Option
<Attribute
> {
506 path
: fld
.fold_path(attr
.path
),
507 tokens
: fld
.fold_tts(attr
.tokens
),
508 is_sugared_doc
: attr
.is_sugared_doc
,
509 span
: fld
.new_span(attr
.span
),
513 pub fn noop_fold_mac
<T
: Folder
>(Spanned {node, span}
: Mac
, fld
: &mut T
) -> Mac
{
516 tts
: fld
.fold_tts(node
.stream()).into(),
517 path
: fld
.fold_path(node
.path
),
519 span
: fld
.new_span(span
)
523 pub fn noop_fold_macro_def
<T
: Folder
>(def
: MacroDef
, fld
: &mut T
) -> MacroDef
{
525 tokens
: fld
.fold_tts(def
.tokens
.into()).into(),
530 pub fn noop_fold_meta_list_item
<T
: Folder
>(li
: NestedMetaItem
, fld
: &mut T
)
533 node
: match li
.node
{
534 NestedMetaItemKind
::MetaItem(mi
) => {
535 NestedMetaItemKind
::MetaItem(fld
.fold_meta_item(mi
))
537 NestedMetaItemKind
::Literal(lit
) => NestedMetaItemKind
::Literal(lit
)
539 span
: fld
.new_span(li
.span
)
543 pub fn noop_fold_meta_item
<T
: Folder
>(mi
: MetaItem
, fld
: &mut T
) -> MetaItem
{
546 node
: match mi
.node
{
547 MetaItemKind
::Word
=> MetaItemKind
::Word
,
548 MetaItemKind
::List(mis
) => {
549 MetaItemKind
::List(mis
.move_map(|e
| fld
.fold_meta_list_item(e
)))
551 MetaItemKind
::NameValue(s
) => MetaItemKind
::NameValue(s
),
553 span
: fld
.new_span(mi
.span
)
557 pub fn noop_fold_arg
<T
: Folder
>(Arg {id, pat, ty}
: Arg
, fld
: &mut T
) -> Arg
{
560 pat
: fld
.fold_pat(pat
),
565 pub fn noop_fold_tt
<T
: Folder
>(tt
: TokenTree
, fld
: &mut T
) -> TokenTree
{
567 TokenTree
::Token(span
, tok
) =>
568 TokenTree
::Token(fld
.new_span(span
), fld
.fold_token(tok
)),
569 TokenTree
::Delimited(span
, delimed
) => TokenTree
::Delimited(fld
.new_span(span
), Delimited
{
570 tts
: fld
.fold_tts(delimed
.stream()).into(),
571 delim
: delimed
.delim
,
576 pub fn noop_fold_tts
<T
: Folder
>(tts
: TokenStream
, fld
: &mut T
) -> TokenStream
{
577 tts
.map(|tt
| fld
.fold_tt(tt
))
580 // apply ident folder if it's an ident, apply other folds to interpolated nodes
581 pub fn noop_fold_token
<T
: Folder
>(t
: token
::Token
, fld
: &mut T
) -> token
::Token
{
583 token
::Ident(id
) => token
::Ident(fld
.fold_ident(id
)),
584 token
::Lifetime(id
) => token
::Lifetime(fld
.fold_ident(id
)),
585 token
::Interpolated(nt
) => {
586 let nt
= match Rc
::try_unwrap(nt
) {
588 Err(nt
) => (*nt
).clone(),
590 Token
::interpolated(fld
.fold_interpolated(nt
.0))
596 /// apply folder to elements of interpolated nodes
598 // NB: this can occur only when applying a fold to partially expanded code, where
599 // parsed pieces have gotten implanted ito *other* macro invocations. This is relevant
600 // for macro hygiene, but possibly not elsewhere.
602 // One problem here occurs because the types for fold_item, fold_stmt, etc. allow the
603 // folder to return *multiple* items; this is a problem for the nodes here, because
604 // they insist on having exactly one piece. One solution would be to mangle the fold
605 // trait to include one-to-many and one-to-one versions of these entry points, but that
606 // would probably confuse a lot of people and help very few. Instead, I'm just going
607 // to put in dynamic checks. I think the performance impact of this will be pretty much
608 // nonexistent. The danger is that someone will apply a fold to a partially expanded
609 // node, and will be confused by the fact that their "fold_item" or "fold_stmt" isn't
610 // getting called on NtItem or NtStmt nodes. Hopefully they'll wind up reading this
611 // comment, and doing something appropriate.
613 // BTW, design choice: I considered just changing the type of, e.g., NtItem to contain
614 // multiple items, but decided against it when I looked at parse_item_or_view_item and
615 // tried to figure out what I would do with multiple items there....
616 pub fn noop_fold_interpolated
<T
: Folder
>(nt
: token
::Nonterminal
, fld
: &mut T
)
617 -> token
::Nonterminal
{
619 token
::NtItem(item
) =>
620 token
::NtItem(fld
.fold_item(item
)
621 // this is probably okay, because the only folds likely
622 // to peek inside interpolated nodes will be renamings/markings,
623 // which map single items to single items
624 .expect_one("expected fold to produce exactly one item")),
625 token
::NtBlock(block
) => token
::NtBlock(fld
.fold_block(block
)),
626 token
::NtStmt(stmt
) =>
627 token
::NtStmt(fld
.fold_stmt(stmt
)
628 // this is probably okay, because the only folds likely
629 // to peek inside interpolated nodes will be renamings/markings,
630 // which map single items to single items
631 .expect_one("expected fold to produce exactly one statement")),
632 token
::NtPat(pat
) => token
::NtPat(fld
.fold_pat(pat
)),
633 token
::NtExpr(expr
) => token
::NtExpr(fld
.fold_expr(expr
)),
634 token
::NtTy(ty
) => token
::NtTy(fld
.fold_ty(ty
)),
635 token
::NtIdent(id
) => token
::NtIdent(Spanned
::<Ident
>{node: fld.fold_ident(id.node), ..id}
),
636 token
::NtMeta(meta
) => token
::NtMeta(fld
.fold_meta_item(meta
)),
637 token
::NtPath(path
) => token
::NtPath(fld
.fold_path(path
)),
638 token
::NtTT(tt
) => token
::NtTT(fld
.fold_tt(tt
)),
639 token
::NtArm(arm
) => token
::NtArm(fld
.fold_arm(arm
)),
640 token
::NtImplItem(item
) =>
641 token
::NtImplItem(fld
.fold_impl_item(item
)
642 .expect_one("expected fold to produce exactly one item")),
643 token
::NtTraitItem(item
) =>
644 token
::NtTraitItem(fld
.fold_trait_item(item
)
645 .expect_one("expected fold to produce exactly one item")),
646 token
::NtGenerics(generics
) => token
::NtGenerics(fld
.fold_generics(generics
)),
647 token
::NtWhereClause(where_clause
) =>
648 token
::NtWhereClause(fld
.fold_where_clause(where_clause
)),
649 token
::NtArg(arg
) => token
::NtArg(fld
.fold_arg(arg
)),
650 token
::NtVis(vis
) => token
::NtVis(fld
.fold_vis(vis
)),
654 pub fn noop_fold_fn_decl
<T
: Folder
>(decl
: P
<FnDecl
>, fld
: &mut T
) -> P
<FnDecl
> {
655 decl
.map(|FnDecl {inputs, output, variadic}
| FnDecl
{
656 inputs
: inputs
.move_map(|x
| fld
.fold_arg(x
)),
657 output
: match output
{
658 FunctionRetTy
::Ty(ty
) => FunctionRetTy
::Ty(fld
.fold_ty(ty
)),
659 FunctionRetTy
::Default(span
) => FunctionRetTy
::Default(fld
.new_span(span
)),
665 pub fn noop_fold_ty_param_bound
<T
>(tpb
: TyParamBound
, fld
: &mut T
)
669 TraitTyParamBound(ty
, modifier
) => TraitTyParamBound(fld
.fold_poly_trait_ref(ty
), modifier
),
670 RegionTyParamBound(lifetime
) => RegionTyParamBound(fld
.fold_lifetime(lifetime
)),
674 pub fn noop_fold_ty_param
<T
: Folder
>(tp
: TyParam
, fld
: &mut T
) -> TyParam
{
675 let TyParam {attrs, id, ident, bounds, default, span}
= tp
;
676 let attrs
: Vec
<_
> = attrs
.into();
678 attrs
: attrs
.into_iter()
679 .flat_map(|x
| fld
.fold_attribute(x
).into_iter())
683 ident
: fld
.fold_ident(ident
),
684 bounds
: fld
.fold_bounds(bounds
),
685 default: default.map(|x
| fld
.fold_ty(x
)),
686 span
: fld
.new_span(span
),
690 pub fn noop_fold_ty_params
<T
: Folder
>(tps
: Vec
<TyParam
>, fld
: &mut T
) -> Vec
<TyParam
> {
691 tps
.move_map(|tp
| fld
.fold_ty_param(tp
))
694 pub fn noop_fold_lifetime
<T
: Folder
>(l
: Lifetime
, fld
: &mut T
) -> Lifetime
{
696 id
: fld
.new_id(l
.id
),
697 ident
: fld
.fold_ident(l
.ident
),
698 span
: fld
.new_span(l
.span
)
702 pub fn noop_fold_lifetime_def
<T
: Folder
>(l
: LifetimeDef
, fld
: &mut T
)
704 let attrs
: Vec
<_
> = l
.attrs
.into();
706 attrs
: attrs
.into_iter()
707 .flat_map(|x
| fld
.fold_attribute(x
).into_iter())
710 lifetime
: fld
.fold_lifetime(l
.lifetime
),
711 bounds
: fld
.fold_lifetimes(l
.bounds
),
715 pub fn noop_fold_lifetimes
<T
: Folder
>(lts
: Vec
<Lifetime
>, fld
: &mut T
) -> Vec
<Lifetime
> {
716 lts
.move_map(|l
| fld
.fold_lifetime(l
))
719 pub fn noop_fold_lifetime_defs
<T
: Folder
>(lts
: Vec
<LifetimeDef
>, fld
: &mut T
)
720 -> Vec
<LifetimeDef
> {
721 lts
.move_map(|l
| fld
.fold_lifetime_def(l
))
724 pub fn noop_fold_opt_lifetime
<T
: Folder
>(o_lt
: Option
<Lifetime
>, fld
: &mut T
)
725 -> Option
<Lifetime
> {
726 o_lt
.map(|lt
| fld
.fold_lifetime(lt
))
729 pub fn noop_fold_generics
<T
: Folder
>(Generics {ty_params, lifetimes, where_clause, span}
: Generics
,
730 fld
: &mut T
) -> Generics
{
732 ty_params
: fld
.fold_ty_params(ty_params
),
733 lifetimes
: fld
.fold_lifetime_defs(lifetimes
),
734 where_clause
: fld
.fold_where_clause(where_clause
),
735 span
: fld
.new_span(span
),
739 pub fn noop_fold_where_clause
<T
: Folder
>(
740 WhereClause {id, predicates, span}
: WhereClause
,
745 predicates
: predicates
.move_map(|predicate
| {
746 fld
.fold_where_predicate(predicate
)
752 pub fn noop_fold_where_predicate
<T
: Folder
>(
753 pred
: WherePredicate
,
757 ast
::WherePredicate
::BoundPredicate(ast
::WhereBoundPredicate
{bound_lifetimes
,
761 ast
::WherePredicate
::BoundPredicate(ast
::WhereBoundPredicate
{
762 bound_lifetimes
: fld
.fold_lifetime_defs(bound_lifetimes
),
763 bounded_ty
: fld
.fold_ty(bounded_ty
),
764 bounds
: bounds
.move_map(|x
| fld
.fold_ty_param_bound(x
)),
765 span
: fld
.new_span(span
)
768 ast
::WherePredicate
::RegionPredicate(ast
::WhereRegionPredicate
{lifetime
,
771 ast
::WherePredicate
::RegionPredicate(ast
::WhereRegionPredicate
{
772 span
: fld
.new_span(span
),
773 lifetime
: fld
.fold_lifetime(lifetime
),
774 bounds
: bounds
.move_map(|bound
| fld
.fold_lifetime(bound
))
777 ast
::WherePredicate
::EqPredicate(ast
::WhereEqPredicate
{id
,
781 ast
::WherePredicate
::EqPredicate(ast
::WhereEqPredicate
{
783 lhs_ty
: fld
.fold_ty(lhs_ty
),
784 rhs_ty
: fld
.fold_ty(rhs_ty
),
785 span
: fld
.new_span(span
)
791 pub fn noop_fold_variant_data
<T
: Folder
>(vdata
: VariantData
, fld
: &mut T
) -> VariantData
{
793 ast
::VariantData
::Struct(fields
, id
) => {
794 ast
::VariantData
::Struct(fields
.move_map(|f
| fld
.fold_struct_field(f
)),
797 ast
::VariantData
::Tuple(fields
, id
) => {
798 ast
::VariantData
::Tuple(fields
.move_map(|f
| fld
.fold_struct_field(f
)),
801 ast
::VariantData
::Unit(id
) => ast
::VariantData
::Unit(fld
.new_id(id
))
805 pub fn noop_fold_trait_ref
<T
: Folder
>(p
: TraitRef
, fld
: &mut T
) -> TraitRef
{
806 let id
= fld
.new_id(p
.ref_id
);
812 path
: fld
.fold_path(path
),
817 pub fn noop_fold_poly_trait_ref
<T
: Folder
>(p
: PolyTraitRef
, fld
: &mut T
) -> PolyTraitRef
{
819 bound_lifetimes
: fld
.fold_lifetime_defs(p
.bound_lifetimes
),
820 trait_ref
: fld
.fold_trait_ref(p
.trait_ref
),
821 span
: fld
.new_span(p
.span
),
825 pub fn noop_fold_struct_field
<T
: Folder
>(f
: StructField
, fld
: &mut T
) -> StructField
{
827 span
: fld
.new_span(f
.span
),
828 id
: fld
.new_id(f
.id
),
829 ident
: f
.ident
.map(|ident
| fld
.fold_ident(ident
)),
830 vis
: fld
.fold_vis(f
.vis
),
831 ty
: fld
.fold_ty(f
.ty
),
832 attrs
: fold_attrs(f
.attrs
, fld
),
836 pub fn noop_fold_field
<T
: Folder
>(f
: Field
, folder
: &mut T
) -> Field
{
838 ident
: respan(f
.ident
.span
, folder
.fold_ident(f
.ident
.node
)),
839 expr
: folder
.fold_expr(f
.expr
),
840 span
: folder
.new_span(f
.span
),
841 is_shorthand
: f
.is_shorthand
,
842 attrs
: fold_thin_attrs(f
.attrs
, folder
),
846 pub fn noop_fold_mt
<T
: Folder
>(MutTy {ty, mutbl}
: MutTy
, folder
: &mut T
) -> MutTy
{
848 ty
: folder
.fold_ty(ty
),
853 pub fn noop_fold_opt_bounds
<T
: Folder
>(b
: Option
<TyParamBounds
>, folder
: &mut T
)
854 -> Option
<TyParamBounds
> {
855 b
.map(|bounds
| folder
.fold_bounds(bounds
))
858 fn noop_fold_bounds
<T
: Folder
>(bounds
: TyParamBounds
, folder
: &mut T
)
860 bounds
.move_map(|bound
| folder
.fold_ty_param_bound(bound
))
863 pub fn noop_fold_block
<T
: Folder
>(b
: P
<Block
>, folder
: &mut T
) -> P
<Block
> {
864 b
.map(|Block {id, stmts, rules, span}
| Block
{
865 id
: folder
.new_id(id
),
866 stmts
: stmts
.move_flat_map(|s
| folder
.fold_stmt(s
).into_iter()),
868 span
: folder
.new_span(span
),
872 pub fn noop_fold_item_kind
<T
: Folder
>(i
: ItemKind
, folder
: &mut T
) -> ItemKind
{
874 ItemKind
::ExternCrate(string
) => ItemKind
::ExternCrate(string
),
875 ItemKind
::Use(view_path
) => {
876 ItemKind
::Use(folder
.fold_view_path(view_path
))
878 ItemKind
::Static(t
, m
, e
) => {
879 ItemKind
::Static(folder
.fold_ty(t
), m
, folder
.fold_expr(e
))
881 ItemKind
::Const(t
, e
) => {
882 ItemKind
::Const(folder
.fold_ty(t
), folder
.fold_expr(e
))
884 ItemKind
::Fn(decl
, unsafety
, constness
, abi
, generics
, body
) => {
885 let generics
= folder
.fold_generics(generics
);
886 let decl
= folder
.fold_fn_decl(decl
);
887 let body
= folder
.fold_block(body
);
888 ItemKind
::Fn(decl
, unsafety
, constness
, abi
, generics
, body
)
890 ItemKind
::Mod(m
) => ItemKind
::Mod(folder
.fold_mod(m
)),
891 ItemKind
::ForeignMod(nm
) => ItemKind
::ForeignMod(folder
.fold_foreign_mod(nm
)),
892 ItemKind
::GlobalAsm(ga
) => ItemKind
::GlobalAsm(folder
.fold_global_asm(ga
)),
893 ItemKind
::Ty(t
, generics
) => {
894 ItemKind
::Ty(folder
.fold_ty(t
), folder
.fold_generics(generics
))
896 ItemKind
::Enum(enum_definition
, generics
) => {
897 let generics
= folder
.fold_generics(generics
);
898 let variants
= enum_definition
.variants
.move_map(|x
| folder
.fold_variant(x
));
899 ItemKind
::Enum(ast
::EnumDef { variants: variants }
, generics
)
901 ItemKind
::Struct(struct_def
, generics
) => {
902 let generics
= folder
.fold_generics(generics
);
903 ItemKind
::Struct(folder
.fold_variant_data(struct_def
), generics
)
905 ItemKind
::Union(struct_def
, generics
) => {
906 let generics
= folder
.fold_generics(generics
);
907 ItemKind
::Union(folder
.fold_variant_data(struct_def
), generics
)
909 ItemKind
::DefaultImpl(unsafety
, ref trait_ref
) => {
910 ItemKind
::DefaultImpl(unsafety
, folder
.fold_trait_ref((*trait_ref
).clone()))
912 ItemKind
::Impl(unsafety
,
918 impl_items
) => ItemKind
::Impl(
922 folder
.fold_generics(generics
),
923 ifce
.map(|trait_ref
| folder
.fold_trait_ref(trait_ref
.clone())),
925 impl_items
.move_flat_map(|item
| folder
.fold_impl_item(item
)),
927 ItemKind
::Trait(unsafety
, generics
, bounds
, items
) => ItemKind
::Trait(
929 folder
.fold_generics(generics
),
930 folder
.fold_bounds(bounds
),
931 items
.move_flat_map(|item
| folder
.fold_trait_item(item
)),
933 ItemKind
::Mac(m
) => ItemKind
::Mac(folder
.fold_mac(m
)),
934 ItemKind
::MacroDef(def
) => ItemKind
::MacroDef(folder
.fold_macro_def(def
)),
938 pub fn noop_fold_trait_item
<T
: Folder
>(i
: TraitItem
, folder
: &mut T
)
939 -> SmallVector
<TraitItem
> {
940 SmallVector
::one(TraitItem
{
941 id
: folder
.new_id(i
.id
),
942 ident
: folder
.fold_ident(i
.ident
),
943 attrs
: fold_attrs(i
.attrs
, folder
),
945 TraitItemKind
::Const(ty
, default) => {
946 TraitItemKind
::Const(folder
.fold_ty(ty
),
947 default.map(|x
| folder
.fold_expr(x
)))
949 TraitItemKind
::Method(sig
, body
) => {
950 TraitItemKind
::Method(noop_fold_method_sig(sig
, folder
),
951 body
.map(|x
| folder
.fold_block(x
)))
953 TraitItemKind
::Type(bounds
, default) => {
954 TraitItemKind
::Type(folder
.fold_bounds(bounds
),
955 default.map(|x
| folder
.fold_ty(x
)))
957 ast
::TraitItemKind
::Macro(mac
) => {
958 TraitItemKind
::Macro(folder
.fold_mac(mac
))
961 span
: folder
.new_span(i
.span
),
966 pub fn noop_fold_impl_item
<T
: Folder
>(i
: ImplItem
, folder
: &mut T
)
967 -> SmallVector
<ImplItem
> {
968 SmallVector
::one(ImplItem
{
969 id
: folder
.new_id(i
.id
),
970 vis
: folder
.fold_vis(i
.vis
),
971 ident
: folder
.fold_ident(i
.ident
),
972 attrs
: fold_attrs(i
.attrs
, folder
),
973 defaultness
: i
.defaultness
,
975 ast
::ImplItemKind
::Const(ty
, expr
) => {
976 ast
::ImplItemKind
::Const(folder
.fold_ty(ty
), folder
.fold_expr(expr
))
978 ast
::ImplItemKind
::Method(sig
, body
) => {
979 ast
::ImplItemKind
::Method(noop_fold_method_sig(sig
, folder
),
980 folder
.fold_block(body
))
982 ast
::ImplItemKind
::Type(ty
) => ast
::ImplItemKind
::Type(folder
.fold_ty(ty
)),
983 ast
::ImplItemKind
::Macro(mac
) => ast
::ImplItemKind
::Macro(folder
.fold_mac(mac
))
985 span
: folder
.new_span(i
.span
),
990 pub fn noop_fold_mod
<T
: Folder
>(Mod {inner, items}
: Mod
, folder
: &mut T
) -> Mod
{
992 inner
: folder
.new_span(inner
),
993 items
: items
.move_flat_map(|x
| folder
.fold_item(x
)),
997 pub fn noop_fold_crate
<T
: Folder
>(Crate {module, attrs, span}
: Crate
,
998 folder
: &mut T
) -> Crate
{
999 let mut items
= folder
.fold_item(P(ast
::Item
{
1000 ident
: keywords
::Invalid
.ident(),
1002 id
: ast
::DUMMY_NODE_ID
,
1003 vis
: ast
::Visibility
::Public
,
1005 node
: ast
::ItemKind
::Mod(module
),
1009 let (module
, attrs
, span
) = match items
.next() {
1011 assert
!(items
.next().is_none(),
1012 "a crate cannot expand to more than one item");
1013 item
.and_then(|ast
::Item { attrs, span, node, .. }
| {
1015 ast
::ItemKind
::Mod(m
) => (m
, attrs
, span
),
1016 _
=> panic
!("fold converted a module to not a module"),
1033 // fold one item into possibly many items
1034 pub fn noop_fold_item
<T
: Folder
>(i
: P
<Item
>, folder
: &mut T
) -> SmallVector
<P
<Item
>> {
1035 SmallVector
::one(i
.map(|i
| folder
.fold_item_simple(i
)))
1038 // fold one item into exactly one item
1039 pub fn noop_fold_item_simple
<T
: Folder
>(Item {id, ident, attrs, node, vis, span, tokens}
: Item
,
1040 folder
: &mut T
) -> Item
{
1042 id
: folder
.new_id(id
),
1043 vis
: folder
.fold_vis(vis
),
1044 ident
: folder
.fold_ident(ident
),
1045 attrs
: fold_attrs(attrs
, folder
),
1046 node
: folder
.fold_item_kind(node
),
1047 span
: folder
.new_span(span
),
1049 // FIXME: if this is replaced with a call to `folder.fold_tts` it causes
1050 // an ICE during resolve... odd!
1055 pub fn noop_fold_foreign_item
<T
: Folder
>(ni
: ForeignItem
, folder
: &mut T
) -> ForeignItem
{
1057 id
: folder
.new_id(ni
.id
),
1058 vis
: folder
.fold_vis(ni
.vis
),
1059 ident
: folder
.fold_ident(ni
.ident
),
1060 attrs
: fold_attrs(ni
.attrs
, folder
),
1061 node
: match ni
.node
{
1062 ForeignItemKind
::Fn(fdec
, generics
) => {
1063 ForeignItemKind
::Fn(folder
.fold_fn_decl(fdec
), folder
.fold_generics(generics
))
1065 ForeignItemKind
::Static(t
, m
) => {
1066 ForeignItemKind
::Static(folder
.fold_ty(t
), m
)
1069 span
: folder
.new_span(ni
.span
)
1073 pub fn noop_fold_method_sig
<T
: Folder
>(sig
: MethodSig
, folder
: &mut T
) -> MethodSig
{
1075 generics
: folder
.fold_generics(sig
.generics
),
1077 unsafety
: sig
.unsafety
,
1078 constness
: sig
.constness
,
1079 decl
: folder
.fold_fn_decl(sig
.decl
)
1083 pub fn noop_fold_pat
<T
: Folder
>(p
: P
<Pat
>, folder
: &mut T
) -> P
<Pat
> {
1084 p
.map(|Pat {id, node, span}
| Pat
{
1085 id
: folder
.new_id(id
),
1087 PatKind
::Wild
=> PatKind
::Wild
,
1088 PatKind
::Ident(binding_mode
, pth1
, sub
) => {
1089 PatKind
::Ident(binding_mode
,
1090 Spanned
{span
: folder
.new_span(pth1
.span
),
1091 node
: folder
.fold_ident(pth1
.node
)},
1092 sub
.map(|x
| folder
.fold_pat(x
)))
1094 PatKind
::Lit(e
) => PatKind
::Lit(folder
.fold_expr(e
)),
1095 PatKind
::TupleStruct(pth
, pats
, ddpos
) => {
1096 PatKind
::TupleStruct(folder
.fold_path(pth
),
1097 pats
.move_map(|x
| folder
.fold_pat(x
)), ddpos
)
1099 PatKind
::Path(opt_qself
, pth
) => {
1100 let opt_qself
= opt_qself
.map(|qself
| {
1101 QSelf { ty: folder.fold_ty(qself.ty), position: qself.position }
1103 PatKind
::Path(opt_qself
, folder
.fold_path(pth
))
1105 PatKind
::Struct(pth
, fields
, etc
) => {
1106 let pth
= folder
.fold_path(pth
);
1107 let fs
= fields
.move_map(|f
| {
1108 Spanned
{ span
: folder
.new_span(f
.span
),
1109 node
: ast
::FieldPat
{
1110 ident
: folder
.fold_ident(f
.node
.ident
),
1111 pat
: folder
.fold_pat(f
.node
.pat
),
1112 is_shorthand
: f
.node
.is_shorthand
,
1113 attrs
: fold_attrs(f
.node
.attrs
.into(), folder
).into()
1116 PatKind
::Struct(pth
, fs
, etc
)
1118 PatKind
::Tuple(elts
, ddpos
) => {
1119 PatKind
::Tuple(elts
.move_map(|x
| folder
.fold_pat(x
)), ddpos
)
1121 PatKind
::Box(inner
) => PatKind
::Box(folder
.fold_pat(inner
)),
1122 PatKind
::Ref(inner
, mutbl
) => PatKind
::Ref(folder
.fold_pat(inner
), mutbl
),
1123 PatKind
::Range(e1
, e2
, end
) => {
1124 PatKind
::Range(folder
.fold_expr(e1
),
1125 folder
.fold_expr(e2
),
1126 folder
.fold_range_end(end
))
1128 PatKind
::Slice(before
, slice
, after
) => {
1129 PatKind
::Slice(before
.move_map(|x
| folder
.fold_pat(x
)),
1130 slice
.map(|x
| folder
.fold_pat(x
)),
1131 after
.move_map(|x
| folder
.fold_pat(x
)))
1133 PatKind
::Mac(mac
) => PatKind
::Mac(folder
.fold_mac(mac
))
1135 span
: folder
.new_span(span
)
1139 pub fn noop_fold_range_end
<T
: Folder
>(end
: RangeEnd
, _folder
: &mut T
) -> RangeEnd
{
1143 pub fn noop_fold_expr
<T
: Folder
>(Expr {id, node, span, attrs}
: Expr
, folder
: &mut T
) -> Expr
{
1146 ExprKind
::Box(e
) => {
1147 ExprKind
::Box(folder
.fold_expr(e
))
1149 ExprKind
::InPlace(p
, e
) => {
1150 ExprKind
::InPlace(folder
.fold_expr(p
), folder
.fold_expr(e
))
1152 ExprKind
::Array(exprs
) => {
1153 ExprKind
::Array(folder
.fold_exprs(exprs
))
1155 ExprKind
::Repeat(expr
, count
) => {
1156 ExprKind
::Repeat(folder
.fold_expr(expr
), folder
.fold_expr(count
))
1158 ExprKind
::Tup(exprs
) => ExprKind
::Tup(folder
.fold_exprs(exprs
)),
1159 ExprKind
::Call(f
, args
) => {
1160 ExprKind
::Call(folder
.fold_expr(f
),
1161 folder
.fold_exprs(args
))
1163 ExprKind
::MethodCall(seg
, args
) => {
1164 ExprKind
::MethodCall(
1166 identifier
: folder
.fold_ident(seg
.identifier
),
1167 span
: folder
.new_span(seg
.span
),
1168 parameters
: seg
.parameters
.map(|ps
| {
1169 ps
.map(|ps
| folder
.fold_path_parameters(ps
))
1172 folder
.fold_exprs(args
))
1174 ExprKind
::Binary(binop
, lhs
, rhs
) => {
1175 ExprKind
::Binary(binop
,
1176 folder
.fold_expr(lhs
),
1177 folder
.fold_expr(rhs
))
1179 ExprKind
::Unary(binop
, ohs
) => {
1180 ExprKind
::Unary(binop
, folder
.fold_expr(ohs
))
1182 ExprKind
::Lit(l
) => ExprKind
::Lit(l
),
1183 ExprKind
::Cast(expr
, ty
) => {
1184 ExprKind
::Cast(folder
.fold_expr(expr
), folder
.fold_ty(ty
))
1186 ExprKind
::Type(expr
, ty
) => {
1187 ExprKind
::Type(folder
.fold_expr(expr
), folder
.fold_ty(ty
))
1189 ExprKind
::AddrOf(m
, ohs
) => ExprKind
::AddrOf(m
, folder
.fold_expr(ohs
)),
1190 ExprKind
::If(cond
, tr
, fl
) => {
1191 ExprKind
::If(folder
.fold_expr(cond
),
1192 folder
.fold_block(tr
),
1193 fl
.map(|x
| folder
.fold_expr(x
)))
1195 ExprKind
::IfLet(pat
, expr
, tr
, fl
) => {
1196 ExprKind
::IfLet(folder
.fold_pat(pat
),
1197 folder
.fold_expr(expr
),
1198 folder
.fold_block(tr
),
1199 fl
.map(|x
| folder
.fold_expr(x
)))
1201 ExprKind
::While(cond
, body
, opt_ident
) => {
1202 ExprKind
::While(folder
.fold_expr(cond
),
1203 folder
.fold_block(body
),
1204 opt_ident
.map(|label
| respan(folder
.new_span(label
.span
),
1205 folder
.fold_ident(label
.node
))))
1207 ExprKind
::WhileLet(pat
, expr
, body
, opt_ident
) => {
1208 ExprKind
::WhileLet(folder
.fold_pat(pat
),
1209 folder
.fold_expr(expr
),
1210 folder
.fold_block(body
),
1211 opt_ident
.map(|label
| respan(folder
.new_span(label
.span
),
1212 folder
.fold_ident(label
.node
))))
1214 ExprKind
::ForLoop(pat
, iter
, body
, opt_ident
) => {
1215 ExprKind
::ForLoop(folder
.fold_pat(pat
),
1216 folder
.fold_expr(iter
),
1217 folder
.fold_block(body
),
1218 opt_ident
.map(|label
| respan(folder
.new_span(label
.span
),
1219 folder
.fold_ident(label
.node
))))
1221 ExprKind
::Loop(body
, opt_ident
) => {
1222 ExprKind
::Loop(folder
.fold_block(body
),
1223 opt_ident
.map(|label
| respan(folder
.new_span(label
.span
),
1224 folder
.fold_ident(label
.node
))))
1226 ExprKind
::Match(expr
, arms
) => {
1227 ExprKind
::Match(folder
.fold_expr(expr
),
1228 arms
.move_map(|x
| folder
.fold_arm(x
)))
1230 ExprKind
::Closure(capture_clause
, decl
, body
, span
) => {
1231 ExprKind
::Closure(capture_clause
,
1232 folder
.fold_fn_decl(decl
),
1233 folder
.fold_expr(body
),
1234 folder
.new_span(span
))
1236 ExprKind
::Block(blk
) => ExprKind
::Block(folder
.fold_block(blk
)),
1237 ExprKind
::Assign(el
, er
) => {
1238 ExprKind
::Assign(folder
.fold_expr(el
), folder
.fold_expr(er
))
1240 ExprKind
::AssignOp(op
, el
, er
) => {
1241 ExprKind
::AssignOp(op
,
1242 folder
.fold_expr(el
),
1243 folder
.fold_expr(er
))
1245 ExprKind
::Field(el
, ident
) => {
1246 ExprKind
::Field(folder
.fold_expr(el
),
1247 respan(folder
.new_span(ident
.span
),
1248 folder
.fold_ident(ident
.node
)))
1250 ExprKind
::TupField(el
, ident
) => {
1251 ExprKind
::TupField(folder
.fold_expr(el
),
1252 respan(folder
.new_span(ident
.span
),
1253 folder
.fold_usize(ident
.node
)))
1255 ExprKind
::Index(el
, er
) => {
1256 ExprKind
::Index(folder
.fold_expr(el
), folder
.fold_expr(er
))
1258 ExprKind
::Range(e1
, e2
, lim
) => {
1259 ExprKind
::Range(e1
.map(|x
| folder
.fold_expr(x
)),
1260 e2
.map(|x
| folder
.fold_expr(x
)),
1263 ExprKind
::Path(qself
, path
) => {
1264 let qself
= qself
.map(|QSelf { ty, position }
| {
1266 ty
: folder
.fold_ty(ty
),
1270 ExprKind
::Path(qself
, folder
.fold_path(path
))
1272 ExprKind
::Break(opt_ident
, opt_expr
) => {
1273 ExprKind
::Break(opt_ident
.map(|label
| respan(folder
.new_span(label
.span
),
1274 folder
.fold_ident(label
.node
))),
1275 opt_expr
.map(|e
| folder
.fold_expr(e
)))
1277 ExprKind
::Continue(opt_ident
) => ExprKind
::Continue(opt_ident
.map(|label
|
1278 respan(folder
.new_span(label
.span
),
1279 folder
.fold_ident(label
.node
)))
1281 ExprKind
::Ret(e
) => ExprKind
::Ret(e
.map(|x
| folder
.fold_expr(x
))),
1282 ExprKind
::InlineAsm(asm
) => ExprKind
::InlineAsm(asm
.map(|asm
| {
1284 inputs
: asm
.inputs
.move_map(|(c
, input
)| {
1285 (c
, folder
.fold_expr(input
))
1287 outputs
: asm
.outputs
.move_map(|out
| {
1289 constraint
: out
.constraint
,
1290 expr
: folder
.fold_expr(out
.expr
),
1292 is_indirect
: out
.is_indirect
,
1298 ExprKind
::Mac(mac
) => ExprKind
::Mac(folder
.fold_mac(mac
)),
1299 ExprKind
::Struct(path
, fields
, maybe_expr
) => {
1300 ExprKind
::Struct(folder
.fold_path(path
),
1301 fields
.move_map(|x
| folder
.fold_field(x
)),
1302 maybe_expr
.map(|x
| folder
.fold_expr(x
)))
1304 ExprKind
::Paren(ex
) => {
1305 let sub_expr
= folder
.fold_expr(ex
);
1307 // Nodes that are equal modulo `Paren` sugar no-ops should have the same ids.
1309 node
: ExprKind
::Paren(sub_expr
),
1310 span
: folder
.new_span(span
),
1311 attrs
: fold_attrs(attrs
.into(), folder
).into(),
1314 ExprKind
::Try(ex
) => ExprKind
::Try(folder
.fold_expr(ex
)),
1315 ExprKind
::Catch(body
) => ExprKind
::Catch(folder
.fold_block(body
)),
1317 id
: folder
.new_id(id
),
1318 span
: folder
.new_span(span
),
1319 attrs
: fold_attrs(attrs
.into(), folder
).into(),
1323 pub fn noop_fold_opt_expr
<T
: Folder
>(e
: P
<Expr
>, folder
: &mut T
) -> Option
<P
<Expr
>> {
1324 Some(folder
.fold_expr(e
))
1327 pub fn noop_fold_exprs
<T
: Folder
>(es
: Vec
<P
<Expr
>>, folder
: &mut T
) -> Vec
<P
<Expr
>> {
1328 es
.move_flat_map(|e
| folder
.fold_opt_expr(e
))
1331 pub fn noop_fold_stmt
<T
: Folder
>(Stmt {node, span, id}
: Stmt
, folder
: &mut T
) -> SmallVector
<Stmt
> {
1332 let id
= folder
.new_id(id
);
1333 let span
= folder
.new_span(span
);
1334 noop_fold_stmt_kind(node
, folder
).into_iter().map(|node
| {
1335 Stmt { id: id, node: node, span: span }
1339 pub fn noop_fold_stmt_kind
<T
: Folder
>(node
: StmtKind
, folder
: &mut T
) -> SmallVector
<StmtKind
> {
1341 StmtKind
::Local(local
) => SmallVector
::one(StmtKind
::Local(folder
.fold_local(local
))),
1342 StmtKind
::Item(item
) => folder
.fold_item(item
).into_iter().map(StmtKind
::Item
).collect(),
1343 StmtKind
::Expr(expr
) => {
1344 folder
.fold_opt_expr(expr
).into_iter().map(StmtKind
::Expr
).collect()
1346 StmtKind
::Semi(expr
) => {
1347 folder
.fold_opt_expr(expr
).into_iter().map(StmtKind
::Semi
).collect()
1349 StmtKind
::Mac(mac
) => SmallVector
::one(StmtKind
::Mac(mac
.map(|(mac
, semi
, attrs
)| {
1350 (folder
.fold_mac(mac
), semi
, fold_attrs(attrs
.into(), folder
).into())
1355 pub fn noop_fold_vis
<T
: Folder
>(vis
: Visibility
, folder
: &mut T
) -> Visibility
{
1357 Visibility
::Restricted { path, id }
=> Visibility
::Restricted
{
1358 path
: path
.map(|path
| folder
.fold_path(path
)),
1359 id
: folder
.new_id(id
)
1368 use ast
::{self, Ident}
;
1369 use util
::parser_testing
::{string_to_crate, matches_codepattern}
;
1374 // this version doesn't care about getting comments or docstrings in.
1375 fn fake_print_crate(s
: &mut pprust
::State
,
1376 krate
: &ast
::Crate
) -> io
::Result
<()> {
1377 s
.print_mod(&krate
.module
, &krate
.attrs
)
1380 // change every identifier to "zz"
1381 struct ToZzIdentFolder
;
1383 impl Folder
for ToZzIdentFolder
{
1384 fn fold_ident(&mut self, _
: ast
::Ident
) -> ast
::Ident
{
1385 Ident
::from_str("zz")
1387 fn fold_mac(&mut self, mac
: ast
::Mac
) -> ast
::Mac
{
1388 fold
::noop_fold_mac(mac
, self)
1392 // maybe add to expand.rs...
1393 macro_rules
! assert_pred
{
1394 ($pred
:expr
, $predname
:expr
, $a
:expr
, $b
:expr
) => (
1396 let pred_val
= $pred
;
1399 if !(pred_val(&a_val
, &b_val
)) {
1400 panic
!("expected args satisfying {}, got {} and {}",
1401 $predname
, a_val
, b_val
);
1407 // make sure idents get transformed everywhere
1408 #[test] fn ident_transformation () {
1409 let mut zz_fold
= ToZzIdentFolder
;
1410 let ast
= string_to_crate(
1411 "#[a] mod b {fn c (d : e, f : g) {h!(i,j,k);l;m}}".to_string());
1412 let folded_crate
= zz_fold
.fold_crate(ast
);
1414 matches_codepattern
,
1415 "matches_codepattern",
1416 pprust
::to_string(|s
| fake_print_crate(s
, &folded_crate
)),
1417 "#[zz]mod zz{fn zz(zz:zz,zz:zz){zz!(zz,zz,zz);zz;zz}}".to_string());
1420 // even inside macro defs....
1421 #[test] fn ident_transformation_in_defs () {
1422 let mut zz_fold
= ToZzIdentFolder
;
1423 let ast
= string_to_crate(
1424 "macro_rules! a {(b $c:expr $(d $e:token)f+ => \
1425 (g $(d $d $e)+))} ".to_string());
1426 let folded_crate
= zz_fold
.fold_crate(ast
);
1428 matches_codepattern
,
1429 "matches_codepattern",
1430 pprust
::to_string(|s
| fake_print_crate(s
, &folded_crate
)),
1431 "macro_rules! zz((zz$zz:zz$(zz $zz:zz)zz+=>(zz$(zz$zz$zz)+)));".to_string());