| //! HIR walker for walking the contents of nodes. |
| //! |
| //! **For an overview of the visitor strategy, see the docs on the |
| //! `super::itemlikevisit::ItemLikeVisitor` trait.** |
| //! |
| //! If you have decided to use this visitor, here are some general |
| //! notes on how to do so: |
| //! |
| //! Each overridden visit method has full control over what |
| //! happens with its node, it can do its own traversal of the node's children, |
| //! call `intravisit::walk_*` to apply the default traversal algorithm, or prevent |
| //! deeper traversal by doing nothing. |
| //! |
| //! When visiting the HIR, the contents of nested items are NOT visited |
| //! by default. This is different from the AST visitor, which does a deep walk. |
| //! Hence this module is called `intravisit`; see the method `visit_nested_item` |
| //! for more details. |
| //! |
| //! Note: it is an important invariant that the default visitor walks |
| //! the body of a function in "execution order" - more concretely, if |
| //! we consider the reverse post-order (RPO) of the CFG implied by the HIR, |
| //! then a pre-order traversal of the HIR is consistent with the CFG RPO |
| //! on the *initial CFG point* of each HIR node, while a post-order traversal |
| //! of the HIR is consistent with the CFG RPO on each *final CFG point* of |
| //! each CFG node. |
| //! |
| //! One thing that follows is that if HIR node A always starts/ends executing |
| //! before HIR node B, then A appears in traversal pre/postorder before B, |
| //! respectively. (This follows from RPO respecting CFG domination). |
| //! |
| //! This order consistency is required in a few places in rustc, for |
| //! example generator inference, and possibly also HIR borrowck. |
| |
| use syntax::ast::{Ident, Name, Attribute}; |
| use syntax_pos::Span; |
| use crate::hir::*; |
| use crate::hir::map::Map; |
| use super::itemlikevisit::DeepVisitor; |
| |
| #[derive(Copy, Clone)] |
| pub enum FnKind<'a> { |
| /// `#[xxx] pub async/const/extern "Abi" fn foo()` |
| ItemFn(Ident, &'a Generics, FnHeader, &'a Visibility, &'a [Attribute]), |
| |
| /// `fn foo(&self)` |
| Method(Ident, &'a MethodSig, Option<&'a Visibility>, &'a [Attribute]), |
| |
| /// `|x, y| {}` |
| Closure(&'a [Attribute]), |
| } |
| |
| impl<'a> FnKind<'a> { |
| pub fn attrs(&self) -> &'a [Attribute] { |
| match *self { |
| FnKind::ItemFn(.., attrs) => attrs, |
| FnKind::Method(.., attrs) => attrs, |
| FnKind::Closure(attrs) => attrs, |
| } |
| } |
| |
| pub fn header(&self) -> Option<&FnHeader> { |
| match *self { |
| FnKind::ItemFn(_, _, ref header, _, _) => Some(header), |
| FnKind::Method(_, ref sig, _, _) => Some(&sig.header), |
| FnKind::Closure(_) => None, |
| } |
| } |
| } |
| |
| /// Specifies what nested things a visitor wants to visit. The most |
| /// common choice is `OnlyBodies`, which will cause the visitor to |
| /// visit fn bodies for fns that it encounters, but skip over nested |
| /// item-like things. |
| /// |
| /// See the comments on `ItemLikeVisitor` for more details on the overall |
| /// visit strategy. |
| pub enum NestedVisitorMap<'this, 'tcx> { |
| /// Do not visit any nested things. When you add a new |
| /// "non-nested" thing, you will want to audit such uses to see if |
| /// they remain valid. |
| /// |
| /// Use this if you are only walking some particular kind of tree |
| /// (i.e., a type, or fn signature) and you don't want to thread a |
| /// HIR map around. |
| None, |
| |
| /// Do not visit nested item-like things, but visit nested things |
| /// that are inside of an item-like. |
| /// |
| /// **This is the most common choice.** A very common pattern is |
| /// to use `visit_all_item_likes()` as an outer loop, |
| /// and to have the visitor that visits the contents of each item |
| /// using this setting. |
| OnlyBodies(&'this Map<'tcx>), |
| |
| /// Visits all nested things, including item-likes. |
| /// |
| /// **This is an unusual choice.** It is used when you want to |
| /// process everything within their lexical context. Typically you |
| /// kick off the visit by doing `walk_krate()`. |
| All(&'this Map<'tcx>), |
| } |
| |
| impl<'this, 'tcx> NestedVisitorMap<'this, 'tcx> { |
| /// Returns the map to use for an "intra item-like" thing (if any). |
| /// E.g., function body. |
| pub fn intra(self) -> Option<&'this Map<'tcx>> { |
| match self { |
| NestedVisitorMap::None => None, |
| NestedVisitorMap::OnlyBodies(map) => Some(map), |
| NestedVisitorMap::All(map) => Some(map), |
| } |
| } |
| |
| /// Returns the map to use for an "item-like" thing (if any). |
| /// E.g., item, impl-item. |
| pub fn inter(self) -> Option<&'this Map<'tcx>> { |
| match self { |
| NestedVisitorMap::None => None, |
| NestedVisitorMap::OnlyBodies(_) => None, |
| NestedVisitorMap::All(map) => Some(map), |
| } |
| } |
| } |
| |
| /// Each method of the Visitor trait is a hook to be potentially |
| /// overridden. Each method's default implementation recursively visits |
| /// the substructure of the input via the corresponding `walk` method; |
| /// e.g., the `visit_mod` method by default calls `intravisit::walk_mod`. |
| /// |
| /// Note that this visitor does NOT visit nested items by default |
| /// (this is why the module is called `intravisit`, to distinguish it |
| /// from the AST's `visit` module, which acts differently). If you |
| /// simply want to visit all items in the crate in some order, you |
| /// should call `Crate::visit_all_items`. Otherwise, see the comment |
| /// on `visit_nested_item` for details on how to visit nested items. |
| /// |
| /// If you want to ensure that your code handles every variant |
| /// explicitly, you need to override each method. (And you also need |
| /// to monitor future changes to `Visitor` in case a new method with a |
| /// new default implementation gets introduced.) |
| pub trait Visitor<'v> : Sized { |
| /////////////////////////////////////////////////////////////////////////// |
| // Nested items. |
| |
| /// The default versions of the `visit_nested_XXX` routines invoke |
| /// this method to get a map to use. By selecting an enum variant, |
| /// you control which kinds of nested HIR are visited; see |
| /// `NestedVisitorMap` for details. By "nested HIR", we are |
| /// referring to bits of HIR that are not directly embedded within |
| /// one another but rather indirectly, through a table in the |
| /// crate. This is done to control dependencies during incremental |
| /// compilation: the non-inline bits of HIR can be tracked and |
| /// hashed separately. |
| /// |
| /// **If for some reason you want the nested behavior, but don't |
| /// have a `Map` at your disposal:** then you should override the |
| /// `visit_nested_XXX` methods, and override this method to |
| /// `panic!()`. This way, if a new `visit_nested_XXX` variant is |
| /// added in the future, we will see the panic in your code and |
| /// fix it appropriately. |
| fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'v>; |
| |
| /// Invoked when a nested item is encountered. By default does |
| /// nothing unless you override `nested_visit_map` to return |
| /// `Some(_)`, in which case it will walk the item. **You probably |
| /// don't want to override this method** -- instead, override |
| /// `nested_visit_map` or use the "shallow" or "deep" visit |
| /// patterns described on `itemlikevisit::ItemLikeVisitor`. The only |
| /// reason to override this method is if you want a nested pattern |
| /// but cannot supply a `Map`; see `nested_visit_map` for advice. |
| #[allow(unused_variables)] |
| fn visit_nested_item(&mut self, id: ItemId) { |
| let opt_item = self.nested_visit_map().inter().map(|map| map.expect_item(id.id)); |
| if let Some(item) = opt_item { |
| self.visit_item(item); |
| } |
| } |
| |
| /// Like `visit_nested_item()`, but for trait items. See |
| /// `visit_nested_item()` for advice on when to override this |
| /// method. |
| #[allow(unused_variables)] |
| fn visit_nested_trait_item(&mut self, id: TraitItemId) { |
| let opt_item = self.nested_visit_map().inter().map(|map| map.trait_item(id)); |
| if let Some(item) = opt_item { |
| self.visit_trait_item(item); |
| } |
| } |
| |
| /// Like `visit_nested_item()`, but for impl items. See |
| /// `visit_nested_item()` for advice on when to override this |
| /// method. |
| #[allow(unused_variables)] |
| fn visit_nested_impl_item(&mut self, id: ImplItemId) { |
| let opt_item = self.nested_visit_map().inter().map(|map| map.impl_item(id)); |
| if let Some(item) = opt_item { |
| self.visit_impl_item(item); |
| } |
| } |
| |
| /// Invoked to visit the body of a function, method or closure. Like |
| /// visit_nested_item, does nothing by default unless you override |
| /// `nested_visit_map` to return `Some(_)`, in which case it will walk the |
| /// body. |
| fn visit_nested_body(&mut self, id: BodyId) { |
| let opt_body = self.nested_visit_map().intra().map(|map| map.body(id)); |
| if let Some(body) = opt_body { |
| self.visit_body(body); |
| } |
| } |
| |
| /// Visits the top-level item and (optionally) nested items / impl items. See |
| /// `visit_nested_item` for details. |
| fn visit_item(&mut self, i: &'v Item) { |
| walk_item(self, i) |
| } |
| |
| fn visit_body(&mut self, b: &'v Body) { |
| walk_body(self, b); |
| } |
| |
| /// When invoking `visit_all_item_likes()`, you need to supply an |
| /// item-like visitor. This method converts a "intra-visit" |
| /// visitor into an item-like visitor that walks the entire tree. |
| /// If you use this, you probably don't want to process the |
| /// contents of nested item-like things, since the outer loop will |
| /// visit them as well. |
| fn as_deep_visitor<'s>(&'s mut self) -> DeepVisitor<'s, Self> { |
| DeepVisitor::new(self) |
| } |
| |
| /////////////////////////////////////////////////////////////////////////// |
| |
| fn visit_id(&mut self, _hir_id: HirId) { |
| // Nothing to do. |
| } |
| fn visit_name(&mut self, _span: Span, _name: Name) { |
| // Nothing to do. |
| } |
| fn visit_ident(&mut self, ident: Ident) { |
| walk_ident(self, ident) |
| } |
| fn visit_mod(&mut self, m: &'v Mod, _s: Span, n: HirId) { |
| walk_mod(self, m, n) |
| } |
| fn visit_foreign_item(&mut self, i: &'v ForeignItem) { |
| walk_foreign_item(self, i) |
| } |
| fn visit_local(&mut self, l: &'v Local) { |
| walk_local(self, l) |
| } |
| fn visit_block(&mut self, b: &'v Block) { |
| walk_block(self, b) |
| } |
| fn visit_stmt(&mut self, s: &'v Stmt) { |
| walk_stmt(self, s) |
| } |
| fn visit_arm(&mut self, a: &'v Arm) { |
| walk_arm(self, a) |
| } |
| fn visit_pat(&mut self, p: &'v Pat) { |
| walk_pat(self, p) |
| } |
| fn visit_anon_const(&mut self, c: &'v AnonConst) { |
| walk_anon_const(self, c) |
| } |
| fn visit_expr(&mut self, ex: &'v Expr) { |
| walk_expr(self, ex) |
| } |
| fn visit_ty(&mut self, t: &'v Ty) { |
| walk_ty(self, t) |
| } |
| fn visit_generic_param(&mut self, p: &'v GenericParam) { |
| walk_generic_param(self, p) |
| } |
| fn visit_generics(&mut self, g: &'v Generics) { |
| walk_generics(self, g) |
| } |
| fn visit_where_predicate(&mut self, predicate: &'v WherePredicate) { |
| walk_where_predicate(self, predicate) |
| } |
| fn visit_fn_decl(&mut self, fd: &'v FnDecl) { |
| walk_fn_decl(self, fd) |
| } |
| fn visit_fn(&mut self, fk: FnKind<'v>, fd: &'v FnDecl, b: BodyId, s: Span, id: HirId) { |
| walk_fn(self, fk, fd, b, s, id) |
| } |
| fn visit_use(&mut self, path: &'v Path, hir_id: HirId) { |
| walk_use(self, path, hir_id) |
| } |
| fn visit_trait_item(&mut self, ti: &'v TraitItem) { |
| walk_trait_item(self, ti) |
| } |
| fn visit_trait_item_ref(&mut self, ii: &'v TraitItemRef) { |
| walk_trait_item_ref(self, ii) |
| } |
| fn visit_impl_item(&mut self, ii: &'v ImplItem) { |
| walk_impl_item(self, ii) |
| } |
| fn visit_impl_item_ref(&mut self, ii: &'v ImplItemRef) { |
| walk_impl_item_ref(self, ii) |
| } |
| fn visit_trait_ref(&mut self, t: &'v TraitRef) { |
| walk_trait_ref(self, t) |
| } |
| fn visit_param_bound(&mut self, bounds: &'v GenericBound) { |
| walk_param_bound(self, bounds) |
| } |
| fn visit_poly_trait_ref(&mut self, t: &'v PolyTraitRef, m: TraitBoundModifier) { |
| walk_poly_trait_ref(self, t, m) |
| } |
| fn visit_variant_data(&mut self, |
| s: &'v VariantData, |
| _: Name, |
| _: &'v Generics, |
| _parent_id: HirId, |
| _: Span) { |
| walk_struct_def(self, s) |
| } |
| fn visit_struct_field(&mut self, s: &'v StructField) { |
| walk_struct_field(self, s) |
| } |
| fn visit_enum_def(&mut self, |
| enum_definition: &'v EnumDef, |
| generics: &'v Generics, |
| item_id: HirId, |
| _: Span) { |
| walk_enum_def(self, enum_definition, generics, item_id) |
| } |
| fn visit_variant(&mut self, v: &'v Variant, g: &'v Generics, item_id: HirId) { |
| walk_variant(self, v, g, item_id) |
| } |
| fn visit_label(&mut self, label: &'v Label) { |
| walk_label(self, label) |
| } |
| fn visit_generic_arg(&mut self, generic_arg: &'v GenericArg) { |
| match generic_arg { |
| GenericArg::Lifetime(lt) => self.visit_lifetime(lt), |
| GenericArg::Type(ty) => self.visit_ty(ty), |
| GenericArg::Const(ct) => self.visit_anon_const(&ct.value), |
| } |
| } |
| fn visit_lifetime(&mut self, lifetime: &'v Lifetime) { |
| walk_lifetime(self, lifetime) |
| } |
| fn visit_qpath(&mut self, qpath: &'v QPath, id: HirId, span: Span) { |
| walk_qpath(self, qpath, id, span) |
| } |
| fn visit_path(&mut self, path: &'v Path, _id: HirId) { |
| walk_path(self, path) |
| } |
| fn visit_path_segment(&mut self, path_span: Span, path_segment: &'v PathSegment) { |
| walk_path_segment(self, path_span, path_segment) |
| } |
| fn visit_generic_args(&mut self, path_span: Span, generic_args: &'v GenericArgs) { |
| walk_generic_args(self, path_span, generic_args) |
| } |
| fn visit_assoc_type_binding(&mut self, type_binding: &'v TypeBinding) { |
| walk_assoc_type_binding(self, type_binding) |
| } |
| fn visit_attribute(&mut self, _attr: &'v Attribute) { |
| } |
| fn visit_macro_def(&mut self, macro_def: &'v MacroDef) { |
| walk_macro_def(self, macro_def) |
| } |
| fn visit_vis(&mut self, vis: &'v Visibility) { |
| walk_vis(self, vis) |
| } |
| fn visit_associated_item_kind(&mut self, kind: &'v AssocItemKind) { |
| walk_associated_item_kind(self, kind); |
| } |
| fn visit_defaultness(&mut self, defaultness: &'v Defaultness) { |
| walk_defaultness(self, defaultness); |
| } |
| } |
| |
| /// Walks the contents of a crate. See also `Crate::visit_all_items`. |
| pub fn walk_crate<'v, V: Visitor<'v>>(visitor: &mut V, krate: &'v Crate) { |
| visitor.visit_mod(&krate.module, krate.span, CRATE_HIR_ID); |
| walk_list!(visitor, visit_attribute, &krate.attrs); |
| walk_list!(visitor, visit_macro_def, &krate.exported_macros); |
| } |
| |
| pub fn walk_macro_def<'v, V: Visitor<'v>>(visitor: &mut V, macro_def: &'v MacroDef) { |
| visitor.visit_id(macro_def.hir_id); |
| visitor.visit_name(macro_def.span, macro_def.name); |
| walk_list!(visitor, visit_attribute, ¯o_def.attrs); |
| } |
| |
| pub fn walk_mod<'v, V: Visitor<'v>>(visitor: &mut V, module: &'v Mod, mod_hir_id: HirId) { |
| visitor.visit_id(mod_hir_id); |
| for &item_id in &module.item_ids { |
| visitor.visit_nested_item(item_id); |
| } |
| } |
| |
| pub fn walk_body<'v, V: Visitor<'v>>(visitor: &mut V, body: &'v Body) { |
| for argument in &body.arguments { |
| visitor.visit_id(argument.hir_id); |
| visitor.visit_pat(&argument.pat); |
| } |
| visitor.visit_expr(&body.value); |
| } |
| |
| pub fn walk_local<'v, V: Visitor<'v>>(visitor: &mut V, local: &'v Local) { |
| // Intentionally visiting the expr first - the initialization expr |
| // dominates the local's definition. |
| walk_list!(visitor, visit_expr, &local.init); |
| walk_list!(visitor, visit_attribute, local.attrs.iter()); |
| visitor.visit_id(local.hir_id); |
| visitor.visit_pat(&local.pat); |
| walk_list!(visitor, visit_ty, &local.ty); |
| } |
| |
| pub fn walk_ident<'v, V: Visitor<'v>>(visitor: &mut V, ident: Ident) { |
| visitor.visit_name(ident.span, ident.name); |
| } |
| |
| pub fn walk_label<'v, V: Visitor<'v>>(visitor: &mut V, label: &'v Label) { |
| visitor.visit_ident(label.ident); |
| } |
| |
| pub fn walk_lifetime<'v, V: Visitor<'v>>(visitor: &mut V, lifetime: &'v Lifetime) { |
| visitor.visit_id(lifetime.hir_id); |
| match lifetime.name { |
| LifetimeName::Param(ParamName::Plain(ident)) => { |
| visitor.visit_ident(ident); |
| } |
| LifetimeName::Param(ParamName::Fresh(_)) | |
| LifetimeName::Param(ParamName::Error) | |
| LifetimeName::Static | |
| LifetimeName::Error | |
| LifetimeName::Implicit | |
| LifetimeName::Underscore => {} |
| } |
| } |
| |
| pub fn walk_poly_trait_ref<'v, V>(visitor: &mut V, |
| trait_ref: &'v PolyTraitRef, |
| _modifier: TraitBoundModifier) |
| where V: Visitor<'v> |
| { |
| walk_list!(visitor, visit_generic_param, &trait_ref.bound_generic_params); |
| visitor.visit_trait_ref(&trait_ref.trait_ref); |
| } |
| |
| pub fn walk_trait_ref<'v, V>(visitor: &mut V, trait_ref: &'v TraitRef) |
| where V: Visitor<'v> |
| { |
| visitor.visit_id(trait_ref.hir_ref_id); |
| visitor.visit_path(&trait_ref.path, trait_ref.hir_ref_id) |
| } |
| |
| pub fn walk_item<'v, V: Visitor<'v>>(visitor: &mut V, item: &'v Item) { |
| visitor.visit_vis(&item.vis); |
| visitor.visit_ident(item.ident); |
| match item.node { |
| ItemKind::ExternCrate(orig_name) => { |
| visitor.visit_id(item.hir_id); |
| if let Some(orig_name) = orig_name { |
| visitor.visit_name(item.span, orig_name); |
| } |
| } |
| ItemKind::Use(ref path, _) => { |
| visitor.visit_use(path, item.hir_id); |
| } |
| ItemKind::Static(ref typ, _, body) | |
| ItemKind::Const(ref typ, body) => { |
| visitor.visit_id(item.hir_id); |
| visitor.visit_ty(typ); |
| visitor.visit_nested_body(body); |
| } |
| ItemKind::Fn(ref declaration, header, ref generics, body_id) => { |
| visitor.visit_fn(FnKind::ItemFn(item.ident, |
| generics, |
| header, |
| &item.vis, |
| &item.attrs), |
| declaration, |
| body_id, |
| item.span, |
| item.hir_id) |
| } |
| ItemKind::Mod(ref module) => { |
| // `visit_mod()` takes care of visiting the `Item`'s `HirId`. |
| visitor.visit_mod(module, item.span, item.hir_id) |
| } |
| ItemKind::ForeignMod(ref foreign_module) => { |
| visitor.visit_id(item.hir_id); |
| walk_list!(visitor, visit_foreign_item, &foreign_module.items); |
| } |
| ItemKind::GlobalAsm(_) => { |
| visitor.visit_id(item.hir_id); |
| } |
| ItemKind::Ty(ref ty, ref generics) => { |
| visitor.visit_id(item.hir_id); |
| visitor.visit_ty(ty); |
| visitor.visit_generics(generics) |
| } |
| ItemKind::Existential(ExistTy { |
| ref generics, |
| ref bounds, |
| .. |
| }) => { |
| visitor.visit_id(item.hir_id); |
| walk_generics(visitor, generics); |
| walk_list!(visitor, visit_param_bound, bounds); |
| } |
| ItemKind::Enum(ref enum_definition, ref generics) => { |
| visitor.visit_generics(generics); |
| // `visit_enum_def()` takes care of visiting the `Item`'s `HirId`. |
| visitor.visit_enum_def(enum_definition, generics, item.hir_id, item.span) |
| } |
| ItemKind::Impl( |
| .., |
| ref generics, |
| ref opt_trait_reference, |
| ref typ, |
| ref impl_item_refs |
| ) => { |
| visitor.visit_id(item.hir_id); |
| visitor.visit_generics(generics); |
| walk_list!(visitor, visit_trait_ref, opt_trait_reference); |
| visitor.visit_ty(typ); |
| walk_list!(visitor, visit_impl_item_ref, impl_item_refs); |
| } |
| ItemKind::Struct(ref struct_definition, ref generics) | |
| ItemKind::Union(ref struct_definition, ref generics) => { |
| visitor.visit_generics(generics); |
| visitor.visit_id(item.hir_id); |
| visitor.visit_variant_data(struct_definition, item.ident.name, generics, item.hir_id, |
| item.span); |
| } |
| ItemKind::Trait(.., ref generics, ref bounds, ref trait_item_refs) => { |
| visitor.visit_id(item.hir_id); |
| visitor.visit_generics(generics); |
| walk_list!(visitor, visit_param_bound, bounds); |
| walk_list!(visitor, visit_trait_item_ref, trait_item_refs); |
| } |
| ItemKind::TraitAlias(ref generics, ref bounds) => { |
| visitor.visit_id(item.hir_id); |
| visitor.visit_generics(generics); |
| walk_list!(visitor, visit_param_bound, bounds); |
| } |
| } |
| walk_list!(visitor, visit_attribute, &item.attrs); |
| } |
| |
| pub fn walk_use<'v, V: Visitor<'v>>(visitor: &mut V, |
| path: &'v Path, |
| hir_id: HirId) { |
| visitor.visit_id(hir_id); |
| visitor.visit_path(path, hir_id); |
| } |
| |
| pub fn walk_enum_def<'v, V: Visitor<'v>>(visitor: &mut V, |
| enum_definition: &'v EnumDef, |
| generics: &'v Generics, |
| item_id: HirId) { |
| visitor.visit_id(item_id); |
| walk_list!(visitor, |
| visit_variant, |
| &enum_definition.variants, |
| generics, |
| item_id); |
| } |
| |
| pub fn walk_variant<'v, V: Visitor<'v>>(visitor: &mut V, |
| variant: &'v Variant, |
| generics: &'v Generics, |
| parent_item_id: HirId) { |
| visitor.visit_ident(variant.node.ident); |
| visitor.visit_id(variant.node.id); |
| visitor.visit_variant_data(&variant.node.data, |
| variant.node.ident.name, |
| generics, |
| parent_item_id, |
| variant.span); |
| walk_list!(visitor, visit_anon_const, &variant.node.disr_expr); |
| walk_list!(visitor, visit_attribute, &variant.node.attrs); |
| } |
| |
| pub fn walk_ty<'v, V: Visitor<'v>>(visitor: &mut V, typ: &'v Ty) { |
| visitor.visit_id(typ.hir_id); |
| |
| match typ.node { |
| TyKind::Slice(ref ty) => { |
| visitor.visit_ty(ty) |
| } |
| TyKind::Ptr(ref mutable_type) => { |
| visitor.visit_ty(&mutable_type.ty) |
| } |
| TyKind::Rptr(ref lifetime, ref mutable_type) => { |
| visitor.visit_lifetime(lifetime); |
| visitor.visit_ty(&mutable_type.ty) |
| } |
| TyKind::Never => {}, |
| TyKind::Tup(ref tuple_element_types) => { |
| walk_list!(visitor, visit_ty, tuple_element_types); |
| } |
| TyKind::BareFn(ref function_declaration) => { |
| walk_list!(visitor, visit_generic_param, &function_declaration.generic_params); |
| visitor.visit_fn_decl(&function_declaration.decl); |
| } |
| TyKind::Path(ref qpath) => { |
| visitor.visit_qpath(qpath, typ.hir_id, typ.span); |
| } |
| TyKind::Def(item_id, ref lifetimes) => { |
| visitor.visit_nested_item(item_id); |
| walk_list!(visitor, visit_generic_arg, lifetimes); |
| } |
| TyKind::Array(ref ty, ref length) => { |
| visitor.visit_ty(ty); |
| visitor.visit_anon_const(length) |
| } |
| TyKind::TraitObject(ref bounds, ref lifetime) => { |
| for bound in bounds { |
| visitor.visit_poly_trait_ref(bound, TraitBoundModifier::None); |
| } |
| visitor.visit_lifetime(lifetime); |
| } |
| TyKind::Typeof(ref expression) => { |
| visitor.visit_anon_const(expression) |
| } |
| TyKind::CVarArgs(ref lt) => { |
| visitor.visit_lifetime(lt) |
| } |
| TyKind::Infer | TyKind::Err => {} |
| } |
| } |
| |
| pub fn walk_qpath<'v, V: Visitor<'v>>(visitor: &mut V, qpath: &'v QPath, id: HirId, span: Span) { |
| match *qpath { |
| QPath::Resolved(ref maybe_qself, ref path) => { |
| if let Some(ref qself) = *maybe_qself { |
| visitor.visit_ty(qself); |
| } |
| visitor.visit_path(path, id) |
| } |
| QPath::TypeRelative(ref qself, ref segment) => { |
| visitor.visit_ty(qself); |
| visitor.visit_path_segment(span, segment); |
| } |
| } |
| } |
| |
| pub fn walk_path<'v, V: Visitor<'v>>(visitor: &mut V, path: &'v Path) { |
| for segment in &path.segments { |
| visitor.visit_path_segment(path.span, segment); |
| } |
| } |
| |
| pub fn walk_path_segment<'v, V: Visitor<'v>>(visitor: &mut V, |
| path_span: Span, |
| segment: &'v PathSegment) { |
| visitor.visit_ident(segment.ident); |
| if let Some(id) = segment.hir_id { |
| visitor.visit_id(id); |
| } |
| if let Some(ref args) = segment.args { |
| visitor.visit_generic_args(path_span, args); |
| } |
| } |
| |
| pub fn walk_generic_args<'v, V: Visitor<'v>>(visitor: &mut V, |
| _path_span: Span, |
| generic_args: &'v GenericArgs) { |
| walk_list!(visitor, visit_generic_arg, &generic_args.args); |
| walk_list!(visitor, visit_assoc_type_binding, &generic_args.bindings); |
| } |
| |
| pub fn walk_assoc_type_binding<'v, V: Visitor<'v>>(visitor: &mut V, |
| type_binding: &'v TypeBinding) { |
| visitor.visit_id(type_binding.hir_id); |
| visitor.visit_ident(type_binding.ident); |
| match type_binding.kind { |
| TypeBindingKind::Equality { ref ty } => { |
| visitor.visit_ty(ty); |
| } |
| TypeBindingKind::Constraint { ref bounds } => { |
| walk_list!(visitor, visit_param_bound, bounds); |
| } |
| } |
| } |
| |
| pub fn walk_pat<'v, V: Visitor<'v>>(visitor: &mut V, pattern: &'v Pat) { |
| visitor.visit_id(pattern.hir_id); |
| match pattern.node { |
| PatKind::TupleStruct(ref qpath, ref children, _) => { |
| visitor.visit_qpath(qpath, pattern.hir_id, pattern.span); |
| walk_list!(visitor, visit_pat, children); |
| } |
| PatKind::Path(ref qpath) => { |
| visitor.visit_qpath(qpath, pattern.hir_id, pattern.span); |
| } |
| PatKind::Struct(ref qpath, ref fields, _) => { |
| visitor.visit_qpath(qpath, pattern.hir_id, pattern.span); |
| for field in fields { |
| visitor.visit_id(field.node.hir_id); |
| visitor.visit_ident(field.node.ident); |
| visitor.visit_pat(&field.node.pat) |
| } |
| } |
| PatKind::Tuple(ref tuple_elements, _) => { |
| walk_list!(visitor, visit_pat, tuple_elements); |
| } |
| PatKind::Box(ref subpattern) | |
| PatKind::Ref(ref subpattern, _) => { |
| visitor.visit_pat(subpattern) |
| } |
| PatKind::Binding(_, _hir_id, ident, ref optional_subpattern) => { |
| visitor.visit_ident(ident); |
| walk_list!(visitor, visit_pat, optional_subpattern); |
| } |
| PatKind::Lit(ref expression) => visitor.visit_expr(expression), |
| PatKind::Range(ref lower_bound, ref upper_bound, _) => { |
| visitor.visit_expr(lower_bound); |
| visitor.visit_expr(upper_bound) |
| } |
| PatKind::Wild => (), |
| PatKind::Slice(ref prepatterns, ref slice_pattern, ref postpatterns) => { |
| walk_list!(visitor, visit_pat, prepatterns); |
| walk_list!(visitor, visit_pat, slice_pattern); |
| walk_list!(visitor, visit_pat, postpatterns); |
| } |
| } |
| } |
| |
| pub fn walk_foreign_item<'v, V: Visitor<'v>>(visitor: &mut V, foreign_item: &'v ForeignItem) { |
| visitor.visit_id(foreign_item.hir_id); |
| visitor.visit_vis(&foreign_item.vis); |
| visitor.visit_ident(foreign_item.ident); |
| |
| match foreign_item.node { |
| ForeignItemKind::Fn(ref function_declaration, ref param_names, ref generics) => { |
| visitor.visit_generics(generics); |
| visitor.visit_fn_decl(function_declaration); |
| for ¶m_name in param_names { |
| visitor.visit_ident(param_name); |
| } |
| } |
| ForeignItemKind::Static(ref typ, _) => visitor.visit_ty(typ), |
| ForeignItemKind::Type => (), |
| } |
| |
| walk_list!(visitor, visit_attribute, &foreign_item.attrs); |
| } |
| |
| pub fn walk_param_bound<'v, V: Visitor<'v>>(visitor: &mut V, bound: &'v GenericBound) { |
| match *bound { |
| GenericBound::Trait(ref typ, modifier) => { |
| visitor.visit_poly_trait_ref(typ, modifier); |
| } |
| GenericBound::Outlives(ref lifetime) => visitor.visit_lifetime(lifetime), |
| } |
| } |
| |
| pub fn walk_generic_param<'v, V: Visitor<'v>>(visitor: &mut V, param: &'v GenericParam) { |
| visitor.visit_id(param.hir_id); |
| walk_list!(visitor, visit_attribute, ¶m.attrs); |
| match param.name { |
| ParamName::Plain(ident) => visitor.visit_ident(ident), |
| ParamName::Error | ParamName::Fresh(_) => {} |
| } |
| match param.kind { |
| GenericParamKind::Lifetime { .. } => {} |
| GenericParamKind::Type { ref default, .. } => walk_list!(visitor, visit_ty, default), |
| GenericParamKind::Const { ref ty } => visitor.visit_ty(ty), |
| } |
| walk_list!(visitor, visit_param_bound, ¶m.bounds); |
| } |
| |
| pub fn walk_generics<'v, V: Visitor<'v>>(visitor: &mut V, generics: &'v Generics) { |
| walk_list!(visitor, visit_generic_param, &generics.params); |
| walk_list!(visitor, visit_where_predicate, &generics.where_clause.predicates); |
| } |
| |
| pub fn walk_where_predicate<'v, V: Visitor<'v>>( |
| visitor: &mut V, |
| predicate: &'v WherePredicate) |
| { |
| match predicate { |
| &WherePredicate::BoundPredicate(WhereBoundPredicate{ref bounded_ty, |
| ref bounds, |
| ref bound_generic_params, |
| ..}) => { |
| visitor.visit_ty(bounded_ty); |
| walk_list!(visitor, visit_param_bound, bounds); |
| walk_list!(visitor, visit_generic_param, bound_generic_params); |
| } |
| &WherePredicate::RegionPredicate(WhereRegionPredicate{ref lifetime, |
| ref bounds, |
| ..}) => { |
| visitor.visit_lifetime(lifetime); |
| walk_list!(visitor, visit_param_bound, bounds); |
| } |
| &WherePredicate::EqPredicate(WhereEqPredicate{hir_id, |
| ref lhs_ty, |
| ref rhs_ty, |
| ..}) => { |
| visitor.visit_id(hir_id); |
| visitor.visit_ty(lhs_ty); |
| visitor.visit_ty(rhs_ty); |
| } |
| } |
| } |
| |
| pub fn walk_fn_ret_ty<'v, V: Visitor<'v>>(visitor: &mut V, ret_ty: &'v FunctionRetTy) { |
| if let Return(ref output_ty) = *ret_ty { |
| visitor.visit_ty(output_ty) |
| } |
| } |
| |
| pub fn walk_fn_decl<'v, V: Visitor<'v>>(visitor: &mut V, function_declaration: &'v FnDecl) { |
| for ty in &function_declaration.inputs { |
| visitor.visit_ty(ty) |
| } |
| walk_fn_ret_ty(visitor, &function_declaration.output) |
| } |
| |
| pub fn walk_fn_kind<'v, V: Visitor<'v>>(visitor: &mut V, function_kind: FnKind<'v>) { |
| match function_kind { |
| FnKind::ItemFn(_, generics, ..) => { |
| visitor.visit_generics(generics); |
| } |
| FnKind::Method(..) | |
| FnKind::Closure(_) => {} |
| } |
| } |
| |
| pub fn walk_fn<'v, V: Visitor<'v>>(visitor: &mut V, |
| function_kind: FnKind<'v>, |
| function_declaration: &'v FnDecl, |
| body_id: BodyId, |
| _span: Span, |
| id: HirId) { |
| visitor.visit_id(id); |
| visitor.visit_fn_decl(function_declaration); |
| walk_fn_kind(visitor, function_kind); |
| visitor.visit_nested_body(body_id) |
| } |
| |
| pub fn walk_trait_item<'v, V: Visitor<'v>>(visitor: &mut V, trait_item: &'v TraitItem) { |
| visitor.visit_ident(trait_item.ident); |
| walk_list!(visitor, visit_attribute, &trait_item.attrs); |
| visitor.visit_generics(&trait_item.generics); |
| match trait_item.node { |
| TraitItemKind::Const(ref ty, default) => { |
| visitor.visit_id(trait_item.hir_id); |
| visitor.visit_ty(ty); |
| walk_list!(visitor, visit_nested_body, default); |
| } |
| TraitItemKind::Method(ref sig, TraitMethod::Required(ref param_names)) => { |
| visitor.visit_id(trait_item.hir_id); |
| visitor.visit_fn_decl(&sig.decl); |
| for ¶m_name in param_names { |
| visitor.visit_ident(param_name); |
| } |
| } |
| TraitItemKind::Method(ref sig, TraitMethod::Provided(body_id)) => { |
| visitor.visit_fn(FnKind::Method(trait_item.ident, |
| sig, |
| None, |
| &trait_item.attrs), |
| &sig.decl, |
| body_id, |
| trait_item.span, |
| trait_item.hir_id); |
| } |
| TraitItemKind::Type(ref bounds, ref default) => { |
| visitor.visit_id(trait_item.hir_id); |
| walk_list!(visitor, visit_param_bound, bounds); |
| walk_list!(visitor, visit_ty, default); |
| } |
| } |
| } |
| |
| pub fn walk_trait_item_ref<'v, V: Visitor<'v>>(visitor: &mut V, trait_item_ref: &'v TraitItemRef) { |
| // N.B., deliberately force a compilation error if/when new fields are added. |
| let TraitItemRef { id, ident, ref kind, span: _, ref defaultness } = *trait_item_ref; |
| visitor.visit_nested_trait_item(id); |
| visitor.visit_ident(ident); |
| visitor.visit_associated_item_kind(kind); |
| visitor.visit_defaultness(defaultness); |
| } |
| |
| pub fn walk_impl_item<'v, V: Visitor<'v>>(visitor: &mut V, impl_item: &'v ImplItem) { |
| // N.B., deliberately force a compilation error if/when new fields are added. |
| let ImplItem { |
| hir_id: _, |
| ident, |
| ref vis, |
| ref defaultness, |
| ref attrs, |
| ref generics, |
| ref node, |
| span: _, |
| } = *impl_item; |
| |
| visitor.visit_ident(ident); |
| visitor.visit_vis(vis); |
| visitor.visit_defaultness(defaultness); |
| walk_list!(visitor, visit_attribute, attrs); |
| visitor.visit_generics(generics); |
| match *node { |
| ImplItemKind::Const(ref ty, body) => { |
| visitor.visit_id(impl_item.hir_id); |
| visitor.visit_ty(ty); |
| visitor.visit_nested_body(body); |
| } |
| ImplItemKind::Method(ref sig, body_id) => { |
| visitor.visit_fn(FnKind::Method(impl_item.ident, |
| sig, |
| Some(&impl_item.vis), |
| &impl_item.attrs), |
| &sig.decl, |
| body_id, |
| impl_item.span, |
| impl_item.hir_id); |
| } |
| ImplItemKind::Type(ref ty) => { |
| visitor.visit_id(impl_item.hir_id); |
| visitor.visit_ty(ty); |
| } |
| ImplItemKind::Existential(ref bounds) => { |
| visitor.visit_id(impl_item.hir_id); |
| walk_list!(visitor, visit_param_bound, bounds); |
| } |
| } |
| } |
| |
| pub fn walk_impl_item_ref<'v, V: Visitor<'v>>(visitor: &mut V, impl_item_ref: &'v ImplItemRef) { |
| // N.B., deliberately force a compilation error if/when new fields are added. |
| let ImplItemRef { id, ident, ref kind, span: _, ref vis, ref defaultness } = *impl_item_ref; |
| visitor.visit_nested_impl_item(id); |
| visitor.visit_ident(ident); |
| visitor.visit_associated_item_kind(kind); |
| visitor.visit_vis(vis); |
| visitor.visit_defaultness(defaultness); |
| } |
| |
| pub fn walk_struct_def<'v, V: Visitor<'v>>(visitor: &mut V, struct_definition: &'v VariantData) { |
| if let Some(ctor_hir_id) = struct_definition.ctor_hir_id() { |
| visitor.visit_id(ctor_hir_id); |
| } |
| walk_list!(visitor, visit_struct_field, struct_definition.fields()); |
| } |
| |
| pub fn walk_struct_field<'v, V: Visitor<'v>>(visitor: &mut V, struct_field: &'v StructField) { |
| visitor.visit_id(struct_field.hir_id); |
| visitor.visit_vis(&struct_field.vis); |
| visitor.visit_ident(struct_field.ident); |
| visitor.visit_ty(&struct_field.ty); |
| walk_list!(visitor, visit_attribute, &struct_field.attrs); |
| } |
| |
| pub fn walk_block<'v, V: Visitor<'v>>(visitor: &mut V, block: &'v Block) { |
| visitor.visit_id(block.hir_id); |
| walk_list!(visitor, visit_stmt, &block.stmts); |
| walk_list!(visitor, visit_expr, &block.expr); |
| } |
| |
| pub fn walk_stmt<'v, V: Visitor<'v>>(visitor: &mut V, statement: &'v Stmt) { |
| visitor.visit_id(statement.hir_id); |
| match statement.node { |
| StmtKind::Local(ref local) => visitor.visit_local(local), |
| StmtKind::Item(item) => visitor.visit_nested_item(item), |
| StmtKind::Expr(ref expression) | |
| StmtKind::Semi(ref expression) => { |
| visitor.visit_expr(expression) |
| } |
| } |
| } |
| |
| pub fn walk_anon_const<'v, V: Visitor<'v>>(visitor: &mut V, constant: &'v AnonConst) { |
| visitor.visit_id(constant.hir_id); |
| visitor.visit_nested_body(constant.body); |
| } |
| |
| pub fn walk_expr<'v, V: Visitor<'v>>(visitor: &mut V, expression: &'v Expr) { |
| visitor.visit_id(expression.hir_id); |
| walk_list!(visitor, visit_attribute, expression.attrs.iter()); |
| match expression.node { |
| ExprKind::Box(ref subexpression) => { |
| visitor.visit_expr(subexpression) |
| } |
| ExprKind::Array(ref subexpressions) => { |
| walk_list!(visitor, visit_expr, subexpressions); |
| } |
| ExprKind::Repeat(ref element, ref count) => { |
| visitor.visit_expr(element); |
| visitor.visit_anon_const(count) |
| } |
| ExprKind::Struct(ref qpath, ref fields, ref optional_base) => { |
| visitor.visit_qpath(qpath, expression.hir_id, expression.span); |
| for field in fields { |
| visitor.visit_id(field.hir_id); |
| visitor.visit_ident(field.ident); |
| visitor.visit_expr(&field.expr) |
| } |
| walk_list!(visitor, visit_expr, optional_base); |
| } |
| ExprKind::Tup(ref subexpressions) => { |
| walk_list!(visitor, visit_expr, subexpressions); |
| } |
| ExprKind::Call(ref callee_expression, ref arguments) => { |
| visitor.visit_expr(callee_expression); |
| walk_list!(visitor, visit_expr, arguments); |
| } |
| ExprKind::MethodCall(ref segment, _, ref arguments) => { |
| visitor.visit_path_segment(expression.span, segment); |
| walk_list!(visitor, visit_expr, arguments); |
| } |
| ExprKind::Binary(_, ref left_expression, ref right_expression) => { |
| visitor.visit_expr(left_expression); |
| visitor.visit_expr(right_expression) |
| } |
| ExprKind::AddrOf(_, ref subexpression) | ExprKind::Unary(_, ref subexpression) => { |
| visitor.visit_expr(subexpression) |
| } |
| ExprKind::Cast(ref subexpression, ref typ) | ExprKind::Type(ref subexpression, ref typ) => { |
| visitor.visit_expr(subexpression); |
| visitor.visit_ty(typ) |
| } |
| ExprKind::DropTemps(ref subexpression) => { |
| visitor.visit_expr(subexpression); |
| } |
| ExprKind::While(ref subexpression, ref block, ref opt_label) => { |
| walk_list!(visitor, visit_label, opt_label); |
| visitor.visit_expr(subexpression); |
| visitor.visit_block(block); |
| } |
| ExprKind::Loop(ref block, ref opt_label, _) => { |
| walk_list!(visitor, visit_label, opt_label); |
| visitor.visit_block(block); |
| } |
| ExprKind::Match(ref subexpression, ref arms, _) => { |
| visitor.visit_expr(subexpression); |
| walk_list!(visitor, visit_arm, arms); |
| } |
| ExprKind::Closure(_, ref function_declaration, body, _fn_decl_span, _gen) => { |
| visitor.visit_fn(FnKind::Closure(&expression.attrs), |
| function_declaration, |
| body, |
| expression.span, |
| expression.hir_id) |
| } |
| ExprKind::Block(ref block, ref opt_label) => { |
| walk_list!(visitor, visit_label, opt_label); |
| visitor.visit_block(block); |
| } |
| ExprKind::Assign(ref left_hand_expression, ref right_hand_expression) => { |
| visitor.visit_expr(right_hand_expression); |
| visitor.visit_expr(left_hand_expression) |
| } |
| ExprKind::AssignOp(_, ref left_expression, ref right_expression) => { |
| visitor.visit_expr(right_expression); |
| visitor.visit_expr(left_expression) |
| } |
| ExprKind::Field(ref subexpression, ident) => { |
| visitor.visit_expr(subexpression); |
| visitor.visit_ident(ident); |
| } |
| ExprKind::Index(ref main_expression, ref index_expression) => { |
| visitor.visit_expr(main_expression); |
| visitor.visit_expr(index_expression) |
| } |
| ExprKind::Path(ref qpath) => { |
| visitor.visit_qpath(qpath, expression.hir_id, expression.span); |
| } |
| ExprKind::Break(ref destination, ref opt_expr) => { |
| if let Some(ref label) = destination.label { |
| visitor.visit_label(label); |
| } |
| walk_list!(visitor, visit_expr, opt_expr); |
| } |
| ExprKind::Continue(ref destination) => { |
| if let Some(ref label) = destination.label { |
| visitor.visit_label(label); |
| } |
| } |
| ExprKind::Ret(ref optional_expression) => { |
| walk_list!(visitor, visit_expr, optional_expression); |
| } |
| ExprKind::InlineAsm(_, ref outputs, ref inputs) => { |
| for expr in outputs.iter().chain(inputs.iter()) { |
| visitor.visit_expr(expr) |
| } |
| } |
| ExprKind::Yield(ref subexpression, _) => { |
| visitor.visit_expr(subexpression); |
| } |
| ExprKind::Lit(_) | ExprKind::Err => {} |
| } |
| } |
| |
| pub fn walk_arm<'v, V: Visitor<'v>>(visitor: &mut V, arm: &'v Arm) { |
| visitor.visit_id(arm.hir_id); |
| walk_list!(visitor, visit_pat, &arm.pats); |
| if let Some(ref g) = arm.guard { |
| match g { |
| Guard::If(ref e) => visitor.visit_expr(e), |
| } |
| } |
| visitor.visit_expr(&arm.body); |
| walk_list!(visitor, visit_attribute, &arm.attrs); |
| } |
| |
| pub fn walk_vis<'v, V: Visitor<'v>>(visitor: &mut V, vis: &'v Visibility) { |
| if let VisibilityKind::Restricted { ref path, hir_id } = vis.node { |
| visitor.visit_id(hir_id); |
| visitor.visit_path(path, hir_id) |
| } |
| } |
| |
| pub fn walk_associated_item_kind<'v, V: Visitor<'v>>(_: &mut V, _: &'v AssocItemKind) { |
| // No visitable content here: this fn exists so you can call it if |
| // the right thing to do, should content be added in the future, |
| // would be to walk it. |
| } |
| |
| pub fn walk_defaultness<'v, V: Visitor<'v>>(_: &mut V, _: &'v Defaultness) { |
| // No visitable content here: this fn exists so you can call it if |
| // the right thing to do, should content be added in the future, |
| // would be to walk it. |
| } |