| // Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| //! A Folder represents an AST->AST fold; it accepts an AST piece, |
| //! and returns a piece of the same type. So, for instance, macro |
| //! expansion is a Folder that walks over an AST and produces another |
| //! AST. |
| //! |
| //! Note: using a Folder (other than the MacroExpander Folder) on |
| //! an AST before macro expansion is probably a bad idea. For instance, |
| //! a folder renaming item names in a module will miss all of those |
| //! that are created by the expansion of a macro. |
| |
| use ast::*; |
| use ast; |
| use attr::{ThinAttributes, ThinAttributesExt}; |
| use ast_util; |
| use codemap::{respan, Span, Spanned}; |
| use parse::token; |
| use ptr::P; |
| use util::small_vector::SmallVector; |
| use util::move_map::MoveMap; |
| |
| use std::rc::Rc; |
| |
| pub trait Folder : Sized { |
| // Any additions to this trait should happen in form |
| // of a call to a public `noop_*` function that only calls |
| // out to the folder again, not other `noop_*` functions. |
| // |
| // This is a necessary API workaround to the problem of not |
| // being able to call out to the super default method |
| // in an overridden default method. |
| |
| fn fold_crate(&mut self, c: Crate) -> Crate { |
| noop_fold_crate(c, self) |
| } |
| |
| fn fold_meta_items(&mut self, meta_items: Vec<P<MetaItem>>) -> Vec<P<MetaItem>> { |
| noop_fold_meta_items(meta_items, self) |
| } |
| |
| fn fold_meta_item(&mut self, meta_item: P<MetaItem>) -> P<MetaItem> { |
| noop_fold_meta_item(meta_item, self) |
| } |
| |
| fn fold_view_path(&mut self, view_path: P<ViewPath>) -> P<ViewPath> { |
| noop_fold_view_path(view_path, self) |
| } |
| |
| fn fold_foreign_item(&mut self, ni: P<ForeignItem>) -> P<ForeignItem> { |
| noop_fold_foreign_item(ni, self) |
| } |
| |
| fn fold_item(&mut self, i: P<Item>) -> SmallVector<P<Item>> { |
| noop_fold_item(i, self) |
| } |
| |
| fn fold_item_simple(&mut self, i: Item) -> Item { |
| noop_fold_item_simple(i, self) |
| } |
| |
| fn fold_struct_field(&mut self, sf: StructField) -> StructField { |
| noop_fold_struct_field(sf, self) |
| } |
| |
| fn fold_item_underscore(&mut self, i: Item_) -> Item_ { |
| noop_fold_item_underscore(i, self) |
| } |
| |
| fn fold_trait_item(&mut self, i: P<TraitItem>) -> SmallVector<P<TraitItem>> { |
| noop_fold_trait_item(i, self) |
| } |
| |
| fn fold_impl_item(&mut self, i: P<ImplItem>) -> SmallVector<P<ImplItem>> { |
| noop_fold_impl_item(i, self) |
| } |
| |
| fn fold_fn_decl(&mut self, d: P<FnDecl>) -> P<FnDecl> { |
| noop_fold_fn_decl(d, self) |
| } |
| |
| fn fold_block(&mut self, b: P<Block>) -> P<Block> { |
| noop_fold_block(b, self) |
| } |
| |
| fn fold_stmt(&mut self, s: P<Stmt>) -> SmallVector<P<Stmt>> { |
| s.and_then(|s| noop_fold_stmt(s, self)) |
| } |
| |
| fn fold_arm(&mut self, a: Arm) -> Arm { |
| noop_fold_arm(a, self) |
| } |
| |
| fn fold_pat(&mut self, p: P<Pat>) -> P<Pat> { |
| noop_fold_pat(p, self) |
| } |
| |
| fn fold_decl(&mut self, d: P<Decl>) -> SmallVector<P<Decl>> { |
| noop_fold_decl(d, self) |
| } |
| |
| fn fold_expr(&mut self, e: P<Expr>) -> P<Expr> { |
| e.map(|e| noop_fold_expr(e, self)) |
| } |
| |
| fn fold_opt_expr(&mut self, e: P<Expr>) -> Option<P<Expr>> { |
| noop_fold_opt_expr(e, self) |
| } |
| |
| fn fold_exprs(&mut self, es: Vec<P<Expr>>) -> Vec<P<Expr>> { |
| noop_fold_exprs(es, self) |
| } |
| |
| fn fold_ty(&mut self, t: P<Ty>) -> P<Ty> { |
| noop_fold_ty(t, self) |
| } |
| |
| fn fold_ty_binding(&mut self, t: P<TypeBinding>) -> P<TypeBinding> { |
| noop_fold_ty_binding(t, self) |
| } |
| |
| fn fold_mod(&mut self, m: Mod) -> Mod { |
| noop_fold_mod(m, self) |
| } |
| |
| fn fold_foreign_mod(&mut self, nm: ForeignMod) -> ForeignMod { |
| noop_fold_foreign_mod(nm, self) |
| } |
| |
| fn fold_variant(&mut self, v: P<Variant>) -> P<Variant> { |
| noop_fold_variant(v, self) |
| } |
| |
| fn fold_ident(&mut self, i: Ident) -> Ident { |
| noop_fold_ident(i, self) |
| } |
| |
| fn fold_usize(&mut self, i: usize) -> usize { |
| noop_fold_usize(i, self) |
| } |
| |
| fn fold_path(&mut self, p: Path) -> Path { |
| noop_fold_path(p, self) |
| } |
| |
| fn fold_path_parameters(&mut self, p: PathParameters) -> PathParameters { |
| noop_fold_path_parameters(p, self) |
| } |
| |
| fn fold_angle_bracketed_parameter_data(&mut self, p: AngleBracketedParameterData) |
| -> AngleBracketedParameterData |
| { |
| noop_fold_angle_bracketed_parameter_data(p, self) |
| } |
| |
| fn fold_parenthesized_parameter_data(&mut self, p: ParenthesizedParameterData) |
| -> ParenthesizedParameterData |
| { |
| noop_fold_parenthesized_parameter_data(p, self) |
| } |
| |
| fn fold_local(&mut self, l: P<Local>) -> P<Local> { |
| noop_fold_local(l, self) |
| } |
| |
| fn fold_mac(&mut self, _mac: Mac) -> Mac { |
| panic!("fold_mac disabled by default"); |
| // NB: see note about macros above. |
| // if you really want a folder that |
| // works on macros, use this |
| // definition in your trait impl: |
| // fold::noop_fold_mac(_mac, self) |
| } |
| |
| fn fold_explicit_self(&mut self, es: ExplicitSelf) -> ExplicitSelf { |
| noop_fold_explicit_self(es, self) |
| } |
| |
| fn fold_explicit_self_underscore(&mut self, es: ExplicitSelf_) -> ExplicitSelf_ { |
| noop_fold_explicit_self_underscore(es, self) |
| } |
| |
| fn fold_lifetime(&mut self, l: Lifetime) -> Lifetime { |
| noop_fold_lifetime(l, self) |
| } |
| |
| fn fold_lifetime_def(&mut self, l: LifetimeDef) -> LifetimeDef { |
| noop_fold_lifetime_def(l, self) |
| } |
| |
| fn fold_attribute(&mut self, at: Attribute) -> Option<Attribute> { |
| noop_fold_attribute(at, self) |
| } |
| |
| fn fold_arg(&mut self, a: Arg) -> Arg { |
| noop_fold_arg(a, self) |
| } |
| |
| fn fold_generics(&mut self, generics: Generics) -> Generics { |
| noop_fold_generics(generics, self) |
| } |
| |
| fn fold_trait_ref(&mut self, p: TraitRef) -> TraitRef { |
| noop_fold_trait_ref(p, self) |
| } |
| |
| fn fold_poly_trait_ref(&mut self, p: PolyTraitRef) -> PolyTraitRef { |
| noop_fold_poly_trait_ref(p, self) |
| } |
| |
| fn fold_variant_data(&mut self, vdata: VariantData) -> VariantData { |
| noop_fold_variant_data(vdata, self) |
| } |
| |
| fn fold_lifetimes(&mut self, lts: Vec<Lifetime>) -> Vec<Lifetime> { |
| noop_fold_lifetimes(lts, self) |
| } |
| |
| fn fold_lifetime_defs(&mut self, lts: Vec<LifetimeDef>) -> Vec<LifetimeDef> { |
| noop_fold_lifetime_defs(lts, self) |
| } |
| |
| fn fold_ty_param(&mut self, tp: TyParam) -> TyParam { |
| noop_fold_ty_param(tp, self) |
| } |
| |
| fn fold_ty_params(&mut self, tps: P<[TyParam]>) -> P<[TyParam]> { |
| noop_fold_ty_params(tps, self) |
| } |
| |
| fn fold_tt(&mut self, tt: &TokenTree) -> TokenTree { |
| noop_fold_tt(tt, self) |
| } |
| |
| fn fold_tts(&mut self, tts: &[TokenTree]) -> Vec<TokenTree> { |
| noop_fold_tts(tts, self) |
| } |
| |
| fn fold_token(&mut self, t: token::Token) -> token::Token { |
| noop_fold_token(t, self) |
| } |
| |
| fn fold_interpolated(&mut self, nt: token::Nonterminal) -> token::Nonterminal { |
| noop_fold_interpolated(nt, self) |
| } |
| |
| fn fold_opt_lifetime(&mut self, o_lt: Option<Lifetime>) -> Option<Lifetime> { |
| noop_fold_opt_lifetime(o_lt, self) |
| } |
| |
| fn fold_opt_bounds(&mut self, b: Option<TyParamBounds>) |
| -> Option<TyParamBounds> { |
| noop_fold_opt_bounds(b, self) |
| } |
| |
| fn fold_bounds(&mut self, b: TyParamBounds) |
| -> TyParamBounds { |
| noop_fold_bounds(b, self) |
| } |
| |
| fn fold_ty_param_bound(&mut self, tpb: TyParamBound) -> TyParamBound { |
| noop_fold_ty_param_bound(tpb, self) |
| } |
| |
| fn fold_mt(&mut self, mt: MutTy) -> MutTy { |
| noop_fold_mt(mt, self) |
| } |
| |
| fn fold_field(&mut self, field: Field) -> Field { |
| noop_fold_field(field, self) |
| } |
| |
| fn fold_where_clause(&mut self, where_clause: WhereClause) |
| -> WhereClause { |
| noop_fold_where_clause(where_clause, self) |
| } |
| |
| fn fold_where_predicate(&mut self, where_predicate: WherePredicate) |
| -> WherePredicate { |
| noop_fold_where_predicate(where_predicate, self) |
| } |
| |
| fn new_id(&mut self, i: NodeId) -> NodeId { |
| i |
| } |
| |
| fn new_span(&mut self, sp: Span) -> Span { |
| sp |
| } |
| } |
| |
| pub fn noop_fold_meta_items<T: Folder>(meta_items: Vec<P<MetaItem>>, fld: &mut T) |
| -> Vec<P<MetaItem>> { |
| meta_items.move_map(|x| fld.fold_meta_item(x)) |
| } |
| |
| pub fn noop_fold_view_path<T: Folder>(view_path: P<ViewPath>, fld: &mut T) -> P<ViewPath> { |
| view_path.map(|Spanned {node, span}| Spanned { |
| node: match node { |
| ViewPathSimple(ident, path) => { |
| ViewPathSimple(ident, fld.fold_path(path)) |
| } |
| ViewPathGlob(path) => { |
| ViewPathGlob(fld.fold_path(path)) |
| } |
| ViewPathList(path, path_list_idents) => { |
| ViewPathList(fld.fold_path(path), |
| path_list_idents.move_map(|path_list_ident| { |
| Spanned { |
| node: match path_list_ident.node { |
| PathListIdent { id, name, rename } => |
| PathListIdent { |
| id: fld.new_id(id), |
| rename: rename, |
| name: name |
| }, |
| PathListMod { id, rename } => |
| PathListMod { |
| id: fld.new_id(id), |
| rename: rename |
| } |
| }, |
| span: fld.new_span(path_list_ident.span) |
| } |
| })) |
| } |
| }, |
| span: fld.new_span(span) |
| }) |
| } |
| |
| pub fn fold_attrs<T: Folder>(attrs: Vec<Attribute>, fld: &mut T) -> Vec<Attribute> { |
| attrs.move_flat_map(|x| fld.fold_attribute(x)) |
| } |
| |
| pub fn fold_thin_attrs<T: Folder>(attrs: ThinAttributes, fld: &mut T) -> ThinAttributes { |
| attrs.map_thin_attrs(|v| fold_attrs(v, fld)) |
| } |
| |
| pub fn noop_fold_arm<T: Folder>(Arm {attrs, pats, guard, body}: Arm, fld: &mut T) -> Arm { |
| Arm { |
| attrs: fold_attrs(attrs, fld), |
| pats: pats.move_map(|x| fld.fold_pat(x)), |
| guard: guard.map(|x| fld.fold_expr(x)), |
| body: fld.fold_expr(body), |
| } |
| } |
| |
| pub fn noop_fold_decl<T: Folder>(d: P<Decl>, fld: &mut T) -> SmallVector<P<Decl>> { |
| d.and_then(|Spanned {node, span}| match node { |
| DeclLocal(l) => SmallVector::one(P(Spanned { |
| node: DeclLocal(fld.fold_local(l)), |
| span: fld.new_span(span) |
| })), |
| DeclItem(it) => fld.fold_item(it).into_iter().map(|i| P(Spanned { |
| node: DeclItem(i), |
| span: fld.new_span(span) |
| })).collect() |
| }) |
| } |
| |
| pub fn noop_fold_ty_binding<T: Folder>(b: P<TypeBinding>, fld: &mut T) -> P<TypeBinding> { |
| b.map(|TypeBinding { id, ident, ty, span }| TypeBinding { |
| id: fld.new_id(id), |
| ident: ident, |
| ty: fld.fold_ty(ty), |
| span: fld.new_span(span), |
| }) |
| } |
| |
| pub fn noop_fold_ty<T: Folder>(t: P<Ty>, fld: &mut T) -> P<Ty> { |
| t.map(|Ty {id, node, span}| Ty { |
| id: fld.new_id(id), |
| node: match node { |
| TyInfer => node, |
| TyVec(ty) => TyVec(fld.fold_ty(ty)), |
| TyPtr(mt) => TyPtr(fld.fold_mt(mt)), |
| TyRptr(region, mt) => { |
| TyRptr(fld.fold_opt_lifetime(region), fld.fold_mt(mt)) |
| } |
| TyBareFn(f) => { |
| TyBareFn(f.map(|BareFnTy {lifetimes, unsafety, abi, decl}| BareFnTy { |
| lifetimes: fld.fold_lifetime_defs(lifetimes), |
| unsafety: unsafety, |
| abi: abi, |
| decl: fld.fold_fn_decl(decl) |
| })) |
| } |
| TyTup(tys) => TyTup(tys.move_map(|ty| fld.fold_ty(ty))), |
| TyParen(ty) => TyParen(fld.fold_ty(ty)), |
| TyPath(qself, path) => { |
| let qself = qself.map(|QSelf { ty, position }| { |
| QSelf { |
| ty: fld.fold_ty(ty), |
| position: position |
| } |
| }); |
| TyPath(qself, fld.fold_path(path)) |
| } |
| TyObjectSum(ty, bounds) => { |
| TyObjectSum(fld.fold_ty(ty), |
| fld.fold_bounds(bounds)) |
| } |
| TyFixedLengthVec(ty, e) => { |
| TyFixedLengthVec(fld.fold_ty(ty), fld.fold_expr(e)) |
| } |
| TyTypeof(expr) => { |
| TyTypeof(fld.fold_expr(expr)) |
| } |
| TyPolyTraitRef(bounds) => { |
| TyPolyTraitRef(bounds.move_map(|b| fld.fold_ty_param_bound(b))) |
| } |
| TyMac(mac) => { |
| TyMac(fld.fold_mac(mac)) |
| } |
| }, |
| span: fld.new_span(span) |
| }) |
| } |
| |
| pub fn noop_fold_foreign_mod<T: Folder>(ForeignMod {abi, items}: ForeignMod, |
| fld: &mut T) -> ForeignMod { |
| ForeignMod { |
| abi: abi, |
| items: items.move_map(|x| fld.fold_foreign_item(x)), |
| } |
| } |
| |
| pub fn noop_fold_variant<T: Folder>(v: P<Variant>, fld: &mut T) -> P<Variant> { |
| v.map(|Spanned {node: Variant_ {name, attrs, data, disr_expr}, span}| Spanned { |
| node: Variant_ { |
| name: name, |
| attrs: fold_attrs(attrs, fld), |
| data: fld.fold_variant_data(data), |
| disr_expr: disr_expr.map(|e| fld.fold_expr(e)), |
| }, |
| span: fld.new_span(span), |
| }) |
| } |
| |
| pub fn noop_fold_ident<T: Folder>(i: Ident, _: &mut T) -> Ident { |
| i |
| } |
| |
| pub fn noop_fold_usize<T: Folder>(i: usize, _: &mut T) -> usize { |
| i |
| } |
| |
| pub fn noop_fold_path<T: Folder>(Path {global, segments, span}: Path, fld: &mut T) -> Path { |
| Path { |
| global: global, |
| segments: segments.move_map(|PathSegment {identifier, parameters}| PathSegment { |
| identifier: fld.fold_ident(identifier), |
| parameters: fld.fold_path_parameters(parameters), |
| }), |
| span: fld.new_span(span) |
| } |
| } |
| |
| pub fn noop_fold_path_parameters<T: Folder>(path_parameters: PathParameters, fld: &mut T) |
| -> PathParameters |
| { |
| match path_parameters { |
| PathParameters::AngleBracketed(data) => |
| PathParameters::AngleBracketed(fld.fold_angle_bracketed_parameter_data(data)), |
| PathParameters::Parenthesized(data) => |
| PathParameters::Parenthesized(fld.fold_parenthesized_parameter_data(data)), |
| } |
| } |
| |
| pub fn noop_fold_angle_bracketed_parameter_data<T: Folder>(data: AngleBracketedParameterData, |
| fld: &mut T) |
| -> AngleBracketedParameterData |
| { |
| let AngleBracketedParameterData { lifetimes, types, bindings } = data; |
| AngleBracketedParameterData { lifetimes: fld.fold_lifetimes(lifetimes), |
| types: types.move_map(|ty| fld.fold_ty(ty)), |
| bindings: bindings.move_map(|b| fld.fold_ty_binding(b)) } |
| } |
| |
| pub fn noop_fold_parenthesized_parameter_data<T: Folder>(data: ParenthesizedParameterData, |
| fld: &mut T) |
| -> ParenthesizedParameterData |
| { |
| let ParenthesizedParameterData { inputs, output, span } = data; |
| ParenthesizedParameterData { inputs: inputs.move_map(|ty| fld.fold_ty(ty)), |
| output: output.map(|ty| fld.fold_ty(ty)), |
| span: fld.new_span(span) } |
| } |
| |
| pub fn noop_fold_local<T: Folder>(l: P<Local>, fld: &mut T) -> P<Local> { |
| l.map(|Local {id, pat, ty, init, span, attrs}| Local { |
| id: fld.new_id(id), |
| ty: ty.map(|t| fld.fold_ty(t)), |
| pat: fld.fold_pat(pat), |
| init: init.map(|e| fld.fold_expr(e)), |
| span: fld.new_span(span), |
| attrs: attrs.map_thin_attrs(|v| fold_attrs(v, fld)), |
| }) |
| } |
| |
| pub fn noop_fold_attribute<T: Folder>(at: Attribute, fld: &mut T) -> Option<Attribute> { |
| let Spanned {node: Attribute_ {id, style, value, is_sugared_doc}, span} = at; |
| Some(Spanned { |
| node: Attribute_ { |
| id: id, |
| style: style, |
| value: fld.fold_meta_item(value), |
| is_sugared_doc: is_sugared_doc |
| }, |
| span: fld.new_span(span) |
| }) |
| } |
| |
| pub fn noop_fold_explicit_self_underscore<T: Folder>(es: ExplicitSelf_, fld: &mut T) |
| -> ExplicitSelf_ { |
| match es { |
| SelfStatic | SelfValue(_) => es, |
| SelfRegion(lifetime, m, ident) => { |
| SelfRegion(fld.fold_opt_lifetime(lifetime), m, ident) |
| } |
| SelfExplicit(typ, ident) => { |
| SelfExplicit(fld.fold_ty(typ), ident) |
| } |
| } |
| } |
| |
| pub fn noop_fold_explicit_self<T: Folder>(Spanned {span, node}: ExplicitSelf, fld: &mut T) |
| -> ExplicitSelf { |
| Spanned { |
| node: fld.fold_explicit_self_underscore(node), |
| span: fld.new_span(span) |
| } |
| } |
| |
| |
| pub fn noop_fold_mac<T: Folder>(Spanned {node, span}: Mac, fld: &mut T) -> Mac { |
| Spanned { |
| node: Mac_ { |
| path: fld.fold_path(node.path), |
| tts: fld.fold_tts(&node.tts), |
| ctxt: node.ctxt, |
| }, |
| span: fld.new_span(span) |
| } |
| } |
| |
| pub fn noop_fold_meta_item<T: Folder>(mi: P<MetaItem>, fld: &mut T) -> P<MetaItem> { |
| mi.map(|Spanned {node, span}| Spanned { |
| node: match node { |
| MetaWord(id) => MetaWord(id), |
| MetaList(id, mis) => { |
| MetaList(id, mis.move_map(|e| fld.fold_meta_item(e))) |
| } |
| MetaNameValue(id, s) => MetaNameValue(id, s) |
| }, |
| span: fld.new_span(span) |
| }) |
| } |
| |
| pub fn noop_fold_arg<T: Folder>(Arg {id, pat, ty}: Arg, fld: &mut T) -> Arg { |
| Arg { |
| id: fld.new_id(id), |
| pat: fld.fold_pat(pat), |
| ty: fld.fold_ty(ty) |
| } |
| } |
| |
| pub fn noop_fold_tt<T: Folder>(tt: &TokenTree, fld: &mut T) -> TokenTree { |
| match *tt { |
| TokenTree::Token(span, ref tok) => |
| TokenTree::Token(span, fld.fold_token(tok.clone())), |
| TokenTree::Delimited(span, ref delimed) => { |
| TokenTree::Delimited(span, Rc::new( |
| Delimited { |
| delim: delimed.delim, |
| open_span: delimed.open_span, |
| tts: fld.fold_tts(&delimed.tts), |
| close_span: delimed.close_span, |
| } |
| )) |
| }, |
| TokenTree::Sequence(span, ref seq) => |
| TokenTree::Sequence(span, |
| Rc::new(SequenceRepetition { |
| tts: fld.fold_tts(&seq.tts), |
| separator: seq.separator.clone().map(|tok| fld.fold_token(tok)), |
| ..**seq |
| })), |
| } |
| } |
| |
| pub fn noop_fold_tts<T: Folder>(tts: &[TokenTree], fld: &mut T) -> Vec<TokenTree> { |
| // FIXME: Does this have to take a tts slice? |
| // Could use move_map otherwise... |
| tts.iter().map(|tt| fld.fold_tt(tt)).collect() |
| } |
| |
| // apply ident folder if it's an ident, apply other folds to interpolated nodes |
| pub fn noop_fold_token<T: Folder>(t: token::Token, fld: &mut T) -> token::Token { |
| match t { |
| token::Ident(id, followed_by_colons) => { |
| token::Ident(fld.fold_ident(id), followed_by_colons) |
| } |
| token::Lifetime(id) => token::Lifetime(fld.fold_ident(id)), |
| token::Interpolated(nt) => token::Interpolated(fld.fold_interpolated(nt)), |
| token::SubstNt(ident, namep) => { |
| token::SubstNt(fld.fold_ident(ident), namep) |
| } |
| token::MatchNt(name, kind, namep, kindp) => { |
| token::MatchNt(fld.fold_ident(name), fld.fold_ident(kind), namep, kindp) |
| } |
| _ => t |
| } |
| } |
| |
| /// apply folder to elements of interpolated nodes |
| // |
| // NB: this can occur only when applying a fold to partially expanded code, where |
| // parsed pieces have gotten implanted ito *other* macro invocations. This is relevant |
| // for macro hygiene, but possibly not elsewhere. |
| // |
| // One problem here occurs because the types for fold_item, fold_stmt, etc. allow the |
| // folder to return *multiple* items; this is a problem for the nodes here, because |
| // they insist on having exactly one piece. One solution would be to mangle the fold |
| // trait to include one-to-many and one-to-one versions of these entry points, but that |
| // would probably confuse a lot of people and help very few. Instead, I'm just going |
| // to put in dynamic checks. I think the performance impact of this will be pretty much |
| // nonexistent. The danger is that someone will apply a fold to a partially expanded |
| // node, and will be confused by the fact that their "fold_item" or "fold_stmt" isn't |
| // getting called on NtItem or NtStmt nodes. Hopefully they'll wind up reading this |
| // comment, and doing something appropriate. |
| // |
| // BTW, design choice: I considered just changing the type of, e.g., NtItem to contain |
| // multiple items, but decided against it when I looked at parse_item_or_view_item and |
| // tried to figure out what I would do with multiple items there.... |
| pub fn noop_fold_interpolated<T: Folder>(nt: token::Nonterminal, fld: &mut T) |
| -> token::Nonterminal { |
| match nt { |
| token::NtItem(item) => |
| token::NtItem(fld.fold_item(item) |
| // this is probably okay, because the only folds likely |
| // to peek inside interpolated nodes will be renamings/markings, |
| // which map single items to single items |
| .expect_one("expected fold to produce exactly one item")), |
| token::NtBlock(block) => token::NtBlock(fld.fold_block(block)), |
| token::NtStmt(stmt) => |
| token::NtStmt(fld.fold_stmt(stmt) |
| // this is probably okay, because the only folds likely |
| // to peek inside interpolated nodes will be renamings/markings, |
| // which map single items to single items |
| .expect_one("expected fold to produce exactly one statement")), |
| token::NtPat(pat) => token::NtPat(fld.fold_pat(pat)), |
| token::NtExpr(expr) => token::NtExpr(fld.fold_expr(expr)), |
| token::NtTy(ty) => token::NtTy(fld.fold_ty(ty)), |
| token::NtIdent(id, is_mod_name) => |
| token::NtIdent(Box::new(Spanned::<Ident>{node: fld.fold_ident(id.node), .. *id}), |
| is_mod_name), |
| token::NtMeta(meta_item) => token::NtMeta(fld.fold_meta_item(meta_item)), |
| token::NtPath(path) => token::NtPath(Box::new(fld.fold_path(*path))), |
| token::NtTT(tt) => token::NtTT(P(fld.fold_tt(&tt))), |
| token::NtArm(arm) => token::NtArm(fld.fold_arm(arm)), |
| token::NtImplItem(arm) => |
| token::NtImplItem(fld.fold_impl_item(arm) |
| .expect_one("expected fold to produce exactly one item")), |
| token::NtTraitItem(arm) => |
| token::NtTraitItem(fld.fold_trait_item(arm) |
| .expect_one("expected fold to produce exactly one item")), |
| token::NtGenerics(generics) => token::NtGenerics(fld.fold_generics(generics)), |
| token::NtWhereClause(where_clause) => |
| token::NtWhereClause(fld.fold_where_clause(where_clause)), |
| token::NtArg(arg) => token::NtArg(fld.fold_arg(arg)), |
| } |
| } |
| |
| pub fn noop_fold_fn_decl<T: Folder>(decl: P<FnDecl>, fld: &mut T) -> P<FnDecl> { |
| decl.map(|FnDecl {inputs, output, variadic}| FnDecl { |
| inputs: inputs.move_map(|x| fld.fold_arg(x)), |
| output: match output { |
| Return(ty) => Return(fld.fold_ty(ty)), |
| DefaultReturn(span) => DefaultReturn(span), |
| NoReturn(span) => NoReturn(span) |
| }, |
| variadic: variadic |
| }) |
| } |
| |
| pub fn noop_fold_ty_param_bound<T>(tpb: TyParamBound, fld: &mut T) |
| -> TyParamBound |
| where T: Folder { |
| match tpb { |
| TraitTyParamBound(ty, modifier) => TraitTyParamBound(fld.fold_poly_trait_ref(ty), modifier), |
| RegionTyParamBound(lifetime) => RegionTyParamBound(fld.fold_lifetime(lifetime)), |
| } |
| } |
| |
| pub fn noop_fold_ty_param<T: Folder>(tp: TyParam, fld: &mut T) -> TyParam { |
| let TyParam {id, ident, bounds, default, span} = tp; |
| TyParam { |
| id: fld.new_id(id), |
| ident: ident, |
| bounds: fld.fold_bounds(bounds), |
| default: default.map(|x| fld.fold_ty(x)), |
| span: span |
| } |
| } |
| |
| pub fn noop_fold_ty_params<T: Folder>(tps: P<[TyParam]>, fld: &mut T) |
| -> P<[TyParam]> { |
| tps.move_map(|tp| fld.fold_ty_param(tp)) |
| } |
| |
| pub fn noop_fold_lifetime<T: Folder>(l: Lifetime, fld: &mut T) -> Lifetime { |
| Lifetime { |
| id: fld.new_id(l.id), |
| name: l.name, |
| span: fld.new_span(l.span) |
| } |
| } |
| |
| pub fn noop_fold_lifetime_def<T: Folder>(l: LifetimeDef, fld: &mut T) |
| -> LifetimeDef { |
| LifetimeDef { |
| lifetime: fld.fold_lifetime(l.lifetime), |
| bounds: fld.fold_lifetimes(l.bounds), |
| } |
| } |
| |
| pub fn noop_fold_lifetimes<T: Folder>(lts: Vec<Lifetime>, fld: &mut T) -> Vec<Lifetime> { |
| lts.move_map(|l| fld.fold_lifetime(l)) |
| } |
| |
| pub fn noop_fold_lifetime_defs<T: Folder>(lts: Vec<LifetimeDef>, fld: &mut T) |
| -> Vec<LifetimeDef> { |
| lts.move_map(|l| fld.fold_lifetime_def(l)) |
| } |
| |
| pub fn noop_fold_opt_lifetime<T: Folder>(o_lt: Option<Lifetime>, fld: &mut T) |
| -> Option<Lifetime> { |
| o_lt.map(|lt| fld.fold_lifetime(lt)) |
| } |
| |
| pub fn noop_fold_generics<T: Folder>(Generics {ty_params, lifetimes, where_clause}: Generics, |
| fld: &mut T) -> Generics { |
| Generics { |
| ty_params: fld.fold_ty_params(ty_params), |
| lifetimes: fld.fold_lifetime_defs(lifetimes), |
| where_clause: fld.fold_where_clause(where_clause), |
| } |
| } |
| |
| pub fn noop_fold_where_clause<T: Folder>( |
| WhereClause {id, predicates}: WhereClause, |
| fld: &mut T) |
| -> WhereClause { |
| WhereClause { |
| id: fld.new_id(id), |
| predicates: predicates.move_map(|predicate| { |
| fld.fold_where_predicate(predicate) |
| }) |
| } |
| } |
| |
| pub fn noop_fold_where_predicate<T: Folder>( |
| pred: WherePredicate, |
| fld: &mut T) |
| -> WherePredicate { |
| match pred { |
| ast::WherePredicate::BoundPredicate(ast::WhereBoundPredicate{bound_lifetimes, |
| bounded_ty, |
| bounds, |
| span}) => { |
| ast::WherePredicate::BoundPredicate(ast::WhereBoundPredicate { |
| bound_lifetimes: fld.fold_lifetime_defs(bound_lifetimes), |
| bounded_ty: fld.fold_ty(bounded_ty), |
| bounds: bounds.move_map(|x| fld.fold_ty_param_bound(x)), |
| span: fld.new_span(span) |
| }) |
| } |
| ast::WherePredicate::RegionPredicate(ast::WhereRegionPredicate{lifetime, |
| bounds, |
| span}) => { |
| ast::WherePredicate::RegionPredicate(ast::WhereRegionPredicate { |
| span: fld.new_span(span), |
| lifetime: fld.fold_lifetime(lifetime), |
| bounds: bounds.move_map(|bound| fld.fold_lifetime(bound)) |
| }) |
| } |
| ast::WherePredicate::EqPredicate(ast::WhereEqPredicate{id, |
| path, |
| ty, |
| span}) => { |
| ast::WherePredicate::EqPredicate(ast::WhereEqPredicate{ |
| id: fld.new_id(id), |
| path: fld.fold_path(path), |
| ty:fld.fold_ty(ty), |
| span: fld.new_span(span) |
| }) |
| } |
| } |
| } |
| |
| pub fn noop_fold_variant_data<T: Folder>(vdata: VariantData, fld: &mut T) -> VariantData { |
| match vdata { |
| ast::VariantData::Struct(fields, id) => { |
| ast::VariantData::Struct(fields.move_map(|f| fld.fold_struct_field(f)), |
| fld.new_id(id)) |
| } |
| ast::VariantData::Tuple(fields, id) => { |
| ast::VariantData::Tuple(fields.move_map(|f| fld.fold_struct_field(f)), |
| fld.new_id(id)) |
| } |
| ast::VariantData::Unit(id) => ast::VariantData::Unit(fld.new_id(id)) |
| } |
| } |
| |
| pub fn noop_fold_trait_ref<T: Folder>(p: TraitRef, fld: &mut T) -> TraitRef { |
| let id = fld.new_id(p.ref_id); |
| let TraitRef { |
| path, |
| ref_id: _, |
| } = p; |
| ast::TraitRef { |
| path: fld.fold_path(path), |
| ref_id: id, |
| } |
| } |
| |
| pub fn noop_fold_poly_trait_ref<T: Folder>(p: PolyTraitRef, fld: &mut T) -> PolyTraitRef { |
| ast::PolyTraitRef { |
| bound_lifetimes: fld.fold_lifetime_defs(p.bound_lifetimes), |
| trait_ref: fld.fold_trait_ref(p.trait_ref), |
| span: fld.new_span(p.span), |
| } |
| } |
| |
| pub fn noop_fold_struct_field<T: Folder>(f: StructField, fld: &mut T) -> StructField { |
| let StructField {node: StructField_ {id, kind, ty, attrs}, span} = f; |
| Spanned { |
| node: StructField_ { |
| id: fld.new_id(id), |
| kind: kind, |
| ty: fld.fold_ty(ty), |
| attrs: fold_attrs(attrs, fld), |
| }, |
| span: fld.new_span(span) |
| } |
| } |
| |
| pub fn noop_fold_field<T: Folder>(Field {ident, expr, span}: Field, folder: &mut T) -> Field { |
| Field { |
| ident: respan(ident.span, folder.fold_ident(ident.node)), |
| expr: folder.fold_expr(expr), |
| span: folder.new_span(span) |
| } |
| } |
| |
| pub fn noop_fold_mt<T: Folder>(MutTy {ty, mutbl}: MutTy, folder: &mut T) -> MutTy { |
| MutTy { |
| ty: folder.fold_ty(ty), |
| mutbl: mutbl, |
| } |
| } |
| |
| pub fn noop_fold_opt_bounds<T: Folder>(b: Option<TyParamBounds>, folder: &mut T) |
| -> Option<TyParamBounds> { |
| b.map(|bounds| folder.fold_bounds(bounds)) |
| } |
| |
| fn noop_fold_bounds<T: Folder>(bounds: TyParamBounds, folder: &mut T) |
| -> TyParamBounds { |
| bounds.move_map(|bound| folder.fold_ty_param_bound(bound)) |
| } |
| |
| pub fn noop_fold_block<T: Folder>(b: P<Block>, folder: &mut T) -> P<Block> { |
| b.map(|Block {id, stmts, expr, rules, span}| Block { |
| id: folder.new_id(id), |
| stmts: stmts.move_flat_map(|s| folder.fold_stmt(s).into_iter()), |
| expr: expr.and_then(|x| folder.fold_opt_expr(x)), |
| rules: rules, |
| span: folder.new_span(span), |
| }) |
| } |
| |
| pub fn noop_fold_item_underscore<T: Folder>(i: Item_, folder: &mut T) -> Item_ { |
| match i { |
| ItemExternCrate(string) => ItemExternCrate(string), |
| ItemUse(view_path) => { |
| ItemUse(folder.fold_view_path(view_path)) |
| } |
| ItemStatic(t, m, e) => { |
| ItemStatic(folder.fold_ty(t), m, folder.fold_expr(e)) |
| } |
| ItemConst(t, e) => { |
| ItemConst(folder.fold_ty(t), folder.fold_expr(e)) |
| } |
| ItemFn(decl, unsafety, constness, abi, generics, body) => { |
| ItemFn( |
| folder.fold_fn_decl(decl), |
| unsafety, |
| constness, |
| abi, |
| folder.fold_generics(generics), |
| folder.fold_block(body) |
| ) |
| } |
| ItemMod(m) => ItemMod(folder.fold_mod(m)), |
| ItemForeignMod(nm) => ItemForeignMod(folder.fold_foreign_mod(nm)), |
| ItemTy(t, generics) => { |
| ItemTy(folder.fold_ty(t), folder.fold_generics(generics)) |
| } |
| ItemEnum(enum_definition, generics) => { |
| ItemEnum( |
| ast::EnumDef { |
| variants: enum_definition.variants.move_map(|x| folder.fold_variant(x)), |
| }, |
| folder.fold_generics(generics)) |
| } |
| ItemStruct(struct_def, generics) => { |
| let struct_def = folder.fold_variant_data(struct_def); |
| ItemStruct(struct_def, folder.fold_generics(generics)) |
| } |
| ItemDefaultImpl(unsafety, ref trait_ref) => { |
| ItemDefaultImpl(unsafety, folder.fold_trait_ref((*trait_ref).clone())) |
| } |
| ItemImpl(unsafety, polarity, generics, ifce, ty, impl_items) => { |
| let new_impl_items = impl_items.move_flat_map(|item| { |
| folder.fold_impl_item(item) |
| }); |
| let ifce = match ifce { |
| None => None, |
| Some(ref trait_ref) => { |
| Some(folder.fold_trait_ref((*trait_ref).clone())) |
| } |
| }; |
| ItemImpl(unsafety, |
| polarity, |
| folder.fold_generics(generics), |
| ifce, |
| folder.fold_ty(ty), |
| new_impl_items) |
| } |
| ItemTrait(unsafety, generics, bounds, items) => { |
| let bounds = folder.fold_bounds(bounds); |
| let items = items.move_flat_map(|item| { |
| folder.fold_trait_item(item) |
| }); |
| ItemTrait(unsafety, |
| folder.fold_generics(generics), |
| bounds, |
| items) |
| } |
| ItemMac(m) => ItemMac(folder.fold_mac(m)), |
| } |
| } |
| |
| pub fn noop_fold_trait_item<T: Folder>(i: P<TraitItem>, folder: &mut T) |
| -> SmallVector<P<TraitItem>> { |
| SmallVector::one(i.map(|TraitItem {id, ident, attrs, node, span}| TraitItem { |
| id: folder.new_id(id), |
| ident: folder.fold_ident(ident), |
| attrs: fold_attrs(attrs, folder), |
| node: match node { |
| ConstTraitItem(ty, default) => { |
| ConstTraitItem(folder.fold_ty(ty), |
| default.map(|x| folder.fold_expr(x))) |
| } |
| MethodTraitItem(sig, body) => { |
| MethodTraitItem(noop_fold_method_sig(sig, folder), |
| body.map(|x| folder.fold_block(x))) |
| } |
| TypeTraitItem(bounds, default) => { |
| TypeTraitItem(folder.fold_bounds(bounds), |
| default.map(|x| folder.fold_ty(x))) |
| } |
| }, |
| span: folder.new_span(span) |
| })) |
| } |
| |
| pub fn noop_fold_impl_item<T: Folder>(i: P<ImplItem>, folder: &mut T) |
| -> SmallVector<P<ImplItem>> { |
| SmallVector::one(i.map(|ImplItem {id, ident, attrs, node, vis, span}| ImplItem { |
| id: folder.new_id(id), |
| ident: folder.fold_ident(ident), |
| attrs: fold_attrs(attrs, folder), |
| vis: vis, |
| node: match node { |
| ast::ImplItemKind::Const(ty, expr) => { |
| ast::ImplItemKind::Const(folder.fold_ty(ty), folder.fold_expr(expr)) |
| } |
| ast::ImplItemKind::Method(sig, body) => { |
| ast::ImplItemKind::Method(noop_fold_method_sig(sig, folder), |
| folder.fold_block(body)) |
| } |
| ast::ImplItemKind::Type(ty) => ast::ImplItemKind::Type(folder.fold_ty(ty)), |
| ast::ImplItemKind::Macro(mac) => ast::ImplItemKind::Macro(folder.fold_mac(mac)) |
| }, |
| span: folder.new_span(span) |
| })) |
| } |
| |
| pub fn noop_fold_mod<T: Folder>(Mod {inner, items}: Mod, folder: &mut T) -> Mod { |
| Mod { |
| inner: folder.new_span(inner), |
| items: items.move_flat_map(|x| folder.fold_item(x)), |
| } |
| } |
| |
| pub fn noop_fold_crate<T: Folder>(Crate {module, attrs, config, mut exported_macros, span}: Crate, |
| folder: &mut T) -> Crate { |
| let config = folder.fold_meta_items(config); |
| |
| let mut items = folder.fold_item(P(ast::Item { |
| ident: token::special_idents::invalid, |
| attrs: attrs, |
| id: ast::DUMMY_NODE_ID, |
| vis: ast::Public, |
| span: span, |
| node: ast::ItemMod(module), |
| })).into_iter(); |
| |
| let (module, attrs, span) = match items.next() { |
| Some(item) => { |
| assert!(items.next().is_none(), |
| "a crate cannot expand to more than one item"); |
| item.and_then(|ast::Item { attrs, span, node, .. }| { |
| match node { |
| ast::ItemMod(m) => (m, attrs, span), |
| _ => panic!("fold converted a module to not a module"), |
| } |
| }) |
| } |
| None => (ast::Mod { |
| inner: span, |
| items: vec![], |
| }, vec![], span) |
| }; |
| |
| for def in &mut exported_macros { |
| def.id = folder.new_id(def.id); |
| } |
| |
| Crate { |
| module: module, |
| attrs: attrs, |
| config: config, |
| exported_macros: exported_macros, |
| span: span, |
| } |
| } |
| |
| // fold one item into possibly many items |
| pub fn noop_fold_item<T: Folder>(i: P<Item>, folder: &mut T) -> SmallVector<P<Item>> { |
| SmallVector::one(i.map(|i| folder.fold_item_simple(i))) |
| } |
| |
| // fold one item into exactly one item |
| pub fn noop_fold_item_simple<T: Folder>(Item {id, ident, attrs, node, vis, span}: Item, |
| folder: &mut T) -> Item { |
| let id = folder.new_id(id); |
| let node = folder.fold_item_underscore(node); |
| let ident = match node { |
| // The node may have changed, recompute the "pretty" impl name. |
| ItemImpl(_, _, _, ref maybe_trait, ref ty, _) => { |
| ast_util::impl_pretty_name(maybe_trait, Some(&**ty)) |
| } |
| _ => ident |
| }; |
| |
| Item { |
| id: id, |
| ident: folder.fold_ident(ident), |
| attrs: fold_attrs(attrs, folder), |
| node: node, |
| vis: vis, |
| span: folder.new_span(span) |
| } |
| } |
| |
| pub fn noop_fold_foreign_item<T: Folder>(ni: P<ForeignItem>, folder: &mut T) -> P<ForeignItem> { |
| ni.map(|ForeignItem {id, ident, attrs, node, span, vis}| ForeignItem { |
| id: folder.new_id(id), |
| ident: folder.fold_ident(ident), |
| attrs: fold_attrs(attrs, folder), |
| node: match node { |
| ForeignItemFn(fdec, generics) => { |
| ForeignItemFn(folder.fold_fn_decl(fdec), folder.fold_generics(generics)) |
| } |
| ForeignItemStatic(t, m) => { |
| ForeignItemStatic(folder.fold_ty(t), m) |
| } |
| }, |
| vis: vis, |
| span: folder.new_span(span) |
| }) |
| } |
| |
| pub fn noop_fold_method_sig<T: Folder>(sig: MethodSig, folder: &mut T) -> MethodSig { |
| MethodSig { |
| generics: folder.fold_generics(sig.generics), |
| abi: sig.abi, |
| explicit_self: folder.fold_explicit_self(sig.explicit_self), |
| unsafety: sig.unsafety, |
| constness: sig.constness, |
| decl: folder.fold_fn_decl(sig.decl) |
| } |
| } |
| |
| pub fn noop_fold_pat<T: Folder>(p: P<Pat>, folder: &mut T) -> P<Pat> { |
| p.map(|Pat {id, node, span}| Pat { |
| id: folder.new_id(id), |
| node: match node { |
| PatWild => PatWild, |
| PatIdent(binding_mode, pth1, sub) => { |
| PatIdent(binding_mode, |
| Spanned{span: folder.new_span(pth1.span), |
| node: folder.fold_ident(pth1.node)}, |
| sub.map(|x| folder.fold_pat(x))) |
| } |
| PatLit(e) => PatLit(folder.fold_expr(e)), |
| PatEnum(pth, pats) => { |
| PatEnum(folder.fold_path(pth), |
| pats.map(|pats| pats.move_map(|x| folder.fold_pat(x)))) |
| } |
| PatQPath(qself, pth) => { |
| let qself = QSelf {ty: folder.fold_ty(qself.ty), .. qself}; |
| PatQPath(qself, folder.fold_path(pth)) |
| } |
| PatStruct(pth, fields, etc) => { |
| let pth = folder.fold_path(pth); |
| let fs = fields.move_map(|f| { |
| Spanned { span: folder.new_span(f.span), |
| node: ast::FieldPat { |
| ident: f.node.ident, |
| pat: folder.fold_pat(f.node.pat), |
| is_shorthand: f.node.is_shorthand, |
| }} |
| }); |
| PatStruct(pth, fs, etc) |
| } |
| PatTup(elts) => PatTup(elts.move_map(|x| folder.fold_pat(x))), |
| PatBox(inner) => PatBox(folder.fold_pat(inner)), |
| PatRegion(inner, mutbl) => PatRegion(folder.fold_pat(inner), mutbl), |
| PatRange(e1, e2) => { |
| PatRange(folder.fold_expr(e1), folder.fold_expr(e2)) |
| }, |
| PatVec(before, slice, after) => { |
| PatVec(before.move_map(|x| folder.fold_pat(x)), |
| slice.map(|x| folder.fold_pat(x)), |
| after.move_map(|x| folder.fold_pat(x))) |
| } |
| PatMac(mac) => PatMac(folder.fold_mac(mac)) |
| }, |
| span: folder.new_span(span) |
| }) |
| } |
| |
| pub fn noop_fold_expr<T: Folder>(Expr {id, node, span, attrs}: Expr, folder: &mut T) -> Expr { |
| Expr { |
| id: folder.new_id(id), |
| node: match node { |
| ExprBox(e) => { |
| ExprBox(folder.fold_expr(e)) |
| } |
| ExprInPlace(p, e) => { |
| ExprInPlace(folder.fold_expr(p), folder.fold_expr(e)) |
| } |
| ExprVec(exprs) => { |
| ExprVec(folder.fold_exprs(exprs)) |
| } |
| ExprRepeat(expr, count) => { |
| ExprRepeat(folder.fold_expr(expr), folder.fold_expr(count)) |
| } |
| ExprTup(exprs) => ExprTup(folder.fold_exprs(exprs)), |
| ExprCall(f, args) => { |
| ExprCall(folder.fold_expr(f), |
| folder.fold_exprs(args)) |
| } |
| ExprMethodCall(i, tps, args) => { |
| ExprMethodCall( |
| respan(folder.new_span(i.span), folder.fold_ident(i.node)), |
| tps.move_map(|x| folder.fold_ty(x)), |
| folder.fold_exprs(args)) |
| } |
| ExprBinary(binop, lhs, rhs) => { |
| ExprBinary(binop, |
| folder.fold_expr(lhs), |
| folder.fold_expr(rhs)) |
| } |
| ExprUnary(binop, ohs) => { |
| ExprUnary(binop, folder.fold_expr(ohs)) |
| } |
| ExprLit(l) => ExprLit(l), |
| ExprCast(expr, ty) => { |
| ExprCast(folder.fold_expr(expr), folder.fold_ty(ty)) |
| } |
| ExprType(expr, ty) => { |
| ExprType(folder.fold_expr(expr), folder.fold_ty(ty)) |
| } |
| ExprAddrOf(m, ohs) => ExprAddrOf(m, folder.fold_expr(ohs)), |
| ExprIf(cond, tr, fl) => { |
| ExprIf(folder.fold_expr(cond), |
| folder.fold_block(tr), |
| fl.map(|x| folder.fold_expr(x))) |
| } |
| ExprIfLet(pat, expr, tr, fl) => { |
| ExprIfLet(folder.fold_pat(pat), |
| folder.fold_expr(expr), |
| folder.fold_block(tr), |
| fl.map(|x| folder.fold_expr(x))) |
| } |
| ExprWhile(cond, body, opt_ident) => { |
| ExprWhile(folder.fold_expr(cond), |
| folder.fold_block(body), |
| opt_ident.map(|i| folder.fold_ident(i))) |
| } |
| ExprWhileLet(pat, expr, body, opt_ident) => { |
| ExprWhileLet(folder.fold_pat(pat), |
| folder.fold_expr(expr), |
| folder.fold_block(body), |
| opt_ident.map(|i| folder.fold_ident(i))) |
| } |
| ExprForLoop(pat, iter, body, opt_ident) => { |
| ExprForLoop(folder.fold_pat(pat), |
| folder.fold_expr(iter), |
| folder.fold_block(body), |
| opt_ident.map(|i| folder.fold_ident(i))) |
| } |
| ExprLoop(body, opt_ident) => { |
| ExprLoop(folder.fold_block(body), |
| opt_ident.map(|i| folder.fold_ident(i))) |
| } |
| ExprMatch(expr, arms) => { |
| ExprMatch(folder.fold_expr(expr), |
| arms.move_map(|x| folder.fold_arm(x))) |
| } |
| ExprClosure(capture_clause, decl, body) => { |
| ExprClosure(capture_clause, |
| folder.fold_fn_decl(decl), |
| folder.fold_block(body)) |
| } |
| ExprBlock(blk) => ExprBlock(folder.fold_block(blk)), |
| ExprAssign(el, er) => { |
| ExprAssign(folder.fold_expr(el), folder.fold_expr(er)) |
| } |
| ExprAssignOp(op, el, er) => { |
| ExprAssignOp(op, |
| folder.fold_expr(el), |
| folder.fold_expr(er)) |
| } |
| ExprField(el, ident) => { |
| ExprField(folder.fold_expr(el), |
| respan(folder.new_span(ident.span), |
| folder.fold_ident(ident.node))) |
| } |
| ExprTupField(el, ident) => { |
| ExprTupField(folder.fold_expr(el), |
| respan(folder.new_span(ident.span), |
| folder.fold_usize(ident.node))) |
| } |
| ExprIndex(el, er) => { |
| ExprIndex(folder.fold_expr(el), folder.fold_expr(er)) |
| } |
| ExprRange(e1, e2) => { |
| ExprRange(e1.map(|x| folder.fold_expr(x)), |
| e2.map(|x| folder.fold_expr(x))) |
| } |
| ExprPath(qself, path) => { |
| let qself = qself.map(|QSelf { ty, position }| { |
| QSelf { |
| ty: folder.fold_ty(ty), |
| position: position |
| } |
| }); |
| ExprPath(qself, folder.fold_path(path)) |
| } |
| ExprBreak(opt_ident) => ExprBreak(opt_ident.map(|label| |
| respan(folder.new_span(label.span), |
| folder.fold_ident(label.node))) |
| ), |
| ExprAgain(opt_ident) => ExprAgain(opt_ident.map(|label| |
| respan(folder.new_span(label.span), |
| folder.fold_ident(label.node))) |
| ), |
| ExprRet(e) => ExprRet(e.map(|x| folder.fold_expr(x))), |
| ExprInlineAsm(InlineAsm { |
| inputs, |
| outputs, |
| asm, |
| asm_str_style, |
| clobbers, |
| volatile, |
| alignstack, |
| dialect, |
| expn_id, |
| }) => ExprInlineAsm(InlineAsm { |
| inputs: inputs.move_map(|(c, input)| { |
| (c, folder.fold_expr(input)) |
| }), |
| outputs: outputs.move_map(|out| { |
| InlineAsmOutput { |
| constraint: out.constraint, |
| expr: folder.fold_expr(out.expr), |
| is_rw: out.is_rw, |
| is_indirect: out.is_indirect, |
| } |
| }), |
| asm: asm, |
| asm_str_style: asm_str_style, |
| clobbers: clobbers, |
| volatile: volatile, |
| alignstack: alignstack, |
| dialect: dialect, |
| expn_id: expn_id, |
| }), |
| ExprMac(mac) => ExprMac(folder.fold_mac(mac)), |
| ExprStruct(path, fields, maybe_expr) => { |
| ExprStruct(folder.fold_path(path), |
| fields.move_map(|x| folder.fold_field(x)), |
| maybe_expr.map(|x| folder.fold_expr(x))) |
| }, |
| ExprParen(ex) => ExprParen(folder.fold_expr(ex)) |
| }, |
| span: folder.new_span(span), |
| attrs: attrs.map_thin_attrs(|v| fold_attrs(v, folder)), |
| } |
| } |
| |
| pub fn noop_fold_opt_expr<T: Folder>(e: P<Expr>, folder: &mut T) -> Option<P<Expr>> { |
| Some(folder.fold_expr(e)) |
| } |
| |
| pub fn noop_fold_exprs<T: Folder>(es: Vec<P<Expr>>, folder: &mut T) -> Vec<P<Expr>> { |
| es.move_flat_map(|e| folder.fold_opt_expr(e)) |
| } |
| |
| pub fn noop_fold_stmt<T: Folder>(Spanned {node, span}: Stmt, folder: &mut T) |
| -> SmallVector<P<Stmt>> { |
| let span = folder.new_span(span); |
| match node { |
| StmtDecl(d, id) => { |
| let id = folder.new_id(id); |
| folder.fold_decl(d).into_iter().map(|d| P(Spanned { |
| node: StmtDecl(d, id), |
| span: span |
| })).collect() |
| } |
| StmtExpr(e, id) => { |
| let id = folder.new_id(id); |
| if let Some(e) = folder.fold_opt_expr(e) { |
| SmallVector::one(P(Spanned { |
| node: StmtExpr(e, id), |
| span: span |
| })) |
| } else { |
| SmallVector::zero() |
| } |
| } |
| StmtSemi(e, id) => { |
| let id = folder.new_id(id); |
| if let Some(e) = folder.fold_opt_expr(e) { |
| SmallVector::one(P(Spanned { |
| node: StmtSemi(e, id), |
| span: span |
| })) |
| } else { |
| SmallVector::zero() |
| } |
| } |
| StmtMac(mac, semi, attrs) => SmallVector::one(P(Spanned { |
| node: StmtMac(mac.map(|m| folder.fold_mac(m)), |
| semi, |
| attrs.map_thin_attrs(|v| fold_attrs(v, folder))), |
| span: span |
| })) |
| } |
| } |
| |
| #[cfg(test)] |
| mod tests { |
| use std::io; |
| use ast; |
| use util::parser_testing::{string_to_crate, matches_codepattern}; |
| use parse::token; |
| use print::pprust; |
| use fold; |
| use super::*; |
| |
| // this version doesn't care about getting comments or docstrings in. |
| fn fake_print_crate(s: &mut pprust::State, |
| krate: &ast::Crate) -> io::Result<()> { |
| s.print_mod(&krate.module, &krate.attrs) |
| } |
| |
| // change every identifier to "zz" |
| struct ToZzIdentFolder; |
| |
| impl Folder for ToZzIdentFolder { |
| fn fold_ident(&mut self, _: ast::Ident) -> ast::Ident { |
| token::str_to_ident("zz") |
| } |
| fn fold_mac(&mut self, mac: ast::Mac) -> ast::Mac { |
| fold::noop_fold_mac(mac, self) |
| } |
| } |
| |
| // maybe add to expand.rs... |
| macro_rules! assert_pred { |
| ($pred:expr, $predname:expr, $a:expr , $b:expr) => ( |
| { |
| let pred_val = $pred; |
| let a_val = $a; |
| let b_val = $b; |
| if !(pred_val(&a_val, &b_val)) { |
| panic!("expected args satisfying {}, got {} and {}", |
| $predname, a_val, b_val); |
| } |
| } |
| ) |
| } |
| |
| // make sure idents get transformed everywhere |
| #[test] fn ident_transformation () { |
| let mut zz_fold = ToZzIdentFolder; |
| let ast = string_to_crate( |
| "#[a] mod b {fn c (d : e, f : g) {h!(i,j,k);l;m}}".to_string()); |
| let folded_crate = zz_fold.fold_crate(ast); |
| assert_pred!( |
| matches_codepattern, |
| "matches_codepattern", |
| pprust::to_string(|s| fake_print_crate(s, &folded_crate)), |
| "#[a]mod zz{fn zz(zz:zz,zz:zz){zz!(zz,zz,zz);zz;zz}}".to_string()); |
| } |
| |
| // even inside macro defs.... |
| #[test] fn ident_transformation_in_defs () { |
| let mut zz_fold = ToZzIdentFolder; |
| let ast = string_to_crate( |
| "macro_rules! a {(b $c:expr $(d $e:token)f+ => \ |
| (g $(d $d $e)+))} ".to_string()); |
| let folded_crate = zz_fold.fold_crate(ast); |
| assert_pred!( |
| matches_codepattern, |
| "matches_codepattern", |
| pprust::to_string(|s| fake_print_crate(s, &folded_crate)), |
| "zz!zz((zz$zz:zz$(zz $zz:zz)zz+=>(zz$(zz$zz$zz)+)));".to_string()); |
| } |
| } |
