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chromium / external / github.com / rust-lang / rust / 9f90d666e0cd9a73ef35b76b6605f9d1f69df849 / . / src / librustc_resolve / lib.rs
blob: f07119035799988fe32cb5c732d530995b3b4bea [file] [log] [blame]
// 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.
#![crate_name = "rustc_resolve"]
#![unstable(feature = "rustc_private")]
#![staged_api]
#![crate_type = "dylib"]
#![crate_type = "rlib"]
#![doc(html_logo_url = "http://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
html_favicon_url = "http://www.rust-lang.org/favicon.ico",
html_root_url = "http://doc.rust-lang.org/nightly/")]
#![feature(alloc)]
#![feature(collections)]
#![feature(core)]
#![feature(hash)]
#![feature(int_uint)]
#![feature(rustc_diagnostic_macros)]
#![feature(rustc_private)]
#![feature(slicing_syntax)]
#![feature(staged_api)]
#![feature(std_misc)]
#[macro_use] extern crate log;
#[macro_use] extern crate syntax;
#[macro_use] #[no_link] extern crate rustc_bitflags;
extern crate rustc;
use self::PatternBindingMode::*;
use self::Namespace::*;
use self::NamespaceResult::*;
use self::NameDefinition::*;
use self::ImportDirectiveSubclass::*;
use self::ResolveResult::*;
use self::FallbackSuggestion::*;
use self::TypeParameters::*;
use self::RibKind::*;
use self::MethodSort::*;
use self::UseLexicalScopeFlag::*;
use self::ModulePrefixResult::*;
use self::NameSearchType::*;
use self::BareIdentifierPatternResolution::*;
use self::ParentLink::*;
use self::ModuleKind::*;
use self::TraitReferenceType::*;
use self::FallbackChecks::*;
use rustc::session::Session;
use rustc::lint;
use rustc::metadata::csearch;
use rustc::metadata::decoder::{DefLike, DlDef, DlField, DlImpl};
use rustc::middle::def::*;
use rustc::middle::lang_items::LanguageItems;
use rustc::middle::pat_util::pat_bindings;
use rustc::middle::privacy::*;
use rustc::middle::subst::{ParamSpace, FnSpace, TypeSpace};
use rustc::middle::ty::{Freevar, FreevarMap, TraitMap, GlobMap};
use rustc::util::nodemap::{NodeMap, NodeSet, DefIdSet, FnvHashMap};
use rustc::util::lev_distance::lev_distance;
use syntax::ast::{Arm, BindByRef, BindByValue, BindingMode, Block, Crate, CrateNum};
use syntax::ast::{DefId, Expr, ExprAgain, ExprBreak, ExprField};
use syntax::ast::{ExprClosure, ExprLoop, ExprWhile, ExprMethodCall};
use syntax::ast::{ExprPath, ExprQPath, ExprStruct, FnDecl};
use syntax::ast::{ForeignItemFn, ForeignItemStatic, Generics};
use syntax::ast::{Ident, ImplItem, Item, ItemConst, ItemEnum, ItemExternCrate};
use syntax::ast::{ItemFn, ItemForeignMod, ItemImpl, ItemMac, ItemMod, ItemStatic};
use syntax::ast::{ItemStruct, ItemTrait, ItemTy, ItemUse};
use syntax::ast::{Local, MethodImplItem, Mod, Name, NodeId};
use syntax::ast::{Pat, PatEnum, PatIdent, PatLit};
use syntax::ast::{PatRange, PatStruct, Path};
use syntax::ast::{PolyTraitRef, PrimTy, SelfExplicit};
use syntax::ast::{RegionTyParamBound, StructField};
use syntax::ast::{TraitRef, TraitTyParamBound};
use syntax::ast::{Ty, TyBool, TyChar, TyF32};
use syntax::ast::{TyF64, TyFloat, TyIs, TyI8, TyI16, TyI32, TyI64, TyInt, TyObjectSum};
use syntax::ast::{TyParam, TyParamBound, TyPath, TyPtr, TyPolyTraitRef, TyQPath};
use syntax::ast::{TyRptr, TyStr, TyUs, TyU8, TyU16, TyU32, TyU64, TyUint};
use syntax::ast::{TypeImplItem};
use syntax::ast;
use syntax::ast_map;
use syntax::ast_util::{PostExpansionMethod, local_def, walk_pat};
use syntax::attr::AttrMetaMethods;
use syntax::ext::mtwt;
use syntax::parse::token::{self, special_names, special_idents};
use syntax::codemap::{Span, Pos};
use syntax::owned_slice::OwnedSlice;
use syntax::visit::{self, Visitor};
use std::collections::{HashMap, HashSet};
use std::collections::hash_map::Entry::{Occupied, Vacant};
use std::cell::{Cell, RefCell};
use std::fmt;
use std::mem::replace;
use std::rc::{Rc, Weak};
use std::uint;
// NB: This module needs to be declared first so diagnostics are
// registered before they are used.
pub mod diagnostics;
mod check_unused;
mod record_exports;
mod build_reduced_graph;
#[derive(Copy)]
struct BindingInfo {
span: Span,
binding_mode: BindingMode,
}
// Map from the name in a pattern to its binding mode.
type BindingMap = HashMap<Name, BindingInfo>;
#[derive(Copy, PartialEq)]
enum PatternBindingMode {
RefutableMode,
LocalIrrefutableMode,
ArgumentIrrefutableMode,
}
#[derive(Copy, PartialEq, Eq, Hash, Debug)]
enum Namespace {
TypeNS,
ValueNS
}
/// A NamespaceResult represents the result of resolving an import in
/// a particular namespace. The result is either definitely-resolved,
/// definitely- unresolved, or unknown.
#[derive(Clone)]
enum NamespaceResult {
/// Means that resolve hasn't gathered enough information yet to determine
/// whether the name is bound in this namespace. (That is, it hasn't
/// resolved all `use` directives yet.)
UnknownResult,
/// Means that resolve has determined that the name is definitely
/// not bound in the namespace.
UnboundResult,
/// Means that resolve has determined that the name is bound in the Module
/// argument, and specified by the NameBindings argument.
BoundResult(Rc<Module>, Rc<NameBindings>)
}
impl NamespaceResult {
fn is_unknown(&self) -> bool {
match *self {
UnknownResult => true,
_ => false
}
}
fn is_unbound(&self) -> bool {
match *self {
UnboundResult => true,
_ => false
}
}
}
enum NameDefinition {
NoNameDefinition, //< The name was unbound.
ChildNameDefinition(Def, LastPrivate), //< The name identifies an immediate child.
ImportNameDefinition(Def, LastPrivate) //< The name identifies an import.
}
impl<'a, 'v, 'tcx> Visitor<'v> for Resolver<'a, 'tcx> {
fn visit_item(&mut self, item: &Item) {
self.resolve_item(item);
}
fn visit_arm(&mut self, arm: &Arm) {
self.resolve_arm(arm);
}
fn visit_block(&mut self, block: &Block) {
self.resolve_block(block);
}
fn visit_expr(&mut self, expr: &Expr) {
self.resolve_expr(expr);
}
fn visit_local(&mut self, local: &Local) {
self.resolve_local(local);
}
fn visit_ty(&mut self, ty: &Ty) {
self.resolve_type(ty);
}
}
/// Contains data for specific types of import directives.
#[derive(Copy,Debug)]
enum ImportDirectiveSubclass {
SingleImport(Name /* target */, Name /* source */),
GlobImport
}
type ErrorMessage = Option<(Span, String)>;
enum ResolveResult<T> {
Failed(ErrorMessage), // Failed to resolve the name, optional helpful error message.
Indeterminate, // Couldn't determine due to unresolved globs.
Success(T) // Successfully resolved the import.
}
impl<T> ResolveResult<T> {
fn indeterminate(&self) -> bool {
match *self { Indeterminate => true, _ => false }
}
}
enum FallbackSuggestion {
NoSuggestion,
Field,
Method,
TraitItem,
StaticMethod(String),
TraitMethod(String),
}
#[derive(Copy)]
enum TypeParameters<'a> {
NoTypeParameters,
HasTypeParameters(
// Type parameters.
&'a Generics,
// Identifies the things that these parameters
// were declared on (type, fn, etc)
ParamSpace,
// ID of the enclosing item.
NodeId,
// The kind of the rib used for type parameters.
RibKind)
}
// The rib kind controls the translation of local
// definitions (`DefLocal`) to upvars (`DefUpvar`).
#[derive(Copy, Debug)]
enum RibKind {
// No translation needs to be applied.
NormalRibKind,
// We passed through a closure scope at the given node ID.
// Translate upvars as appropriate.
ClosureRibKind(NodeId /* func id */),
// We passed through an impl or trait and are now in one of its
// methods. Allow references to ty params that impl or trait
// binds. Disallow any other upvars (including other ty params that are
// upvars).
// parent; method itself
MethodRibKind(NodeId, MethodSort),
// We passed through an item scope. Disallow upvars.
ItemRibKind,
// We're in a constant item. Can't refer to dynamic stuff.
ConstantItemRibKind
}
// Methods can be required or provided. RequiredMethod methods only occur in traits.
#[derive(Copy, Debug)]
enum MethodSort {
RequiredMethod,
ProvidedMethod(NodeId)
}
#[derive(Copy)]
enum UseLexicalScopeFlag {
DontUseLexicalScope,
UseLexicalScope
}
enum ModulePrefixResult {
NoPrefixFound,
PrefixFound(Rc<Module>, uint)
}
#[derive(Copy, PartialEq)]
enum NameSearchType {
/// We're doing a name search in order to resolve a `use` directive.
ImportSearch,
/// We're doing a name search in order to resolve a path type, a path
/// expression, or a path pattern.
PathSearch,
}
#[derive(Copy)]
enum BareIdentifierPatternResolution {
FoundStructOrEnumVariant(Def, LastPrivate),
FoundConst(Def, LastPrivate),
BareIdentifierPatternUnresolved
}
/// One local scope.
#[derive(Debug)]
struct Rib {
bindings: HashMap<Name, DefLike>,
kind: RibKind,
}
impl Rib {
fn new(kind: RibKind) -> Rib {
Rib {
bindings: HashMap::new(),
kind: kind
}
}
}
/// Whether an import can be shadowed by another import.
#[derive(Debug,PartialEq,Clone,Copy)]
enum Shadowable {
Always,
Never
}
/// One import directive.
#[derive(Debug)]
struct ImportDirective {
module_path: Vec<Name>,
subclass: ImportDirectiveSubclass,
span: Span,
id: NodeId,
is_public: bool, // see note in ImportResolution about how to use this
shadowable: Shadowable,
}
impl ImportDirective {
fn new(module_path: Vec<Name> ,
subclass: ImportDirectiveSubclass,
span: Span,
id: NodeId,
is_public: bool,
shadowable: Shadowable)
-> ImportDirective {
ImportDirective {
module_path: module_path,
subclass: subclass,
span: span,
id: id,
is_public: is_public,
shadowable: shadowable,
}
}
}
/// The item that an import resolves to.
#[derive(Clone,Debug)]
struct Target {
target_module: Rc<Module>,
bindings: Rc<NameBindings>,
shadowable: Shadowable,
}
impl Target {
fn new(target_module: Rc<Module>,
bindings: Rc<NameBindings>,
shadowable: Shadowable)
-> Target {
Target {
target_module: target_module,
bindings: bindings,
shadowable: shadowable,
}
}
}
/// An ImportResolution represents a particular `use` directive.
#[derive(Debug)]
struct ImportResolution {
/// Whether this resolution came from a `use` or a `pub use`. Note that this
/// should *not* be used whenever resolution is being performed, this is
/// only looked at for glob imports statements currently. Privacy testing
/// occurs during a later phase of compilation.
is_public: bool,
// The number of outstanding references to this name. When this reaches
// zero, outside modules can count on the targets being correct. Before
// then, all bets are off; future imports could override this name.
outstanding_references: uint,
/// The value that this `use` directive names, if there is one.
value_target: Option<Target>,
/// The source node of the `use` directive leading to the value target
/// being non-none
value_id: NodeId,
/// The type that this `use` directive names, if there is one.
type_target: Option<Target>,
/// The source node of the `use` directive leading to the type target
/// being non-none
type_id: NodeId,
}
impl ImportResolution {
fn new(id: NodeId, is_public: bool) -> ImportResolution {
ImportResolution {
type_id: id,
value_id: id,
outstanding_references: 0,
value_target: None,
type_target: None,
is_public: is_public,
}
}
fn target_for_namespace(&self, namespace: Namespace)
-> Option<Target> {
match namespace {
TypeNS => self.type_target.clone(),
ValueNS => self.value_target.clone(),
}
}
fn id(&self, namespace: Namespace) -> NodeId {
match namespace {
TypeNS => self.type_id,
ValueNS => self.value_id,
}
}
fn shadowable(&self, namespace: Namespace) -> Shadowable {
let target = self.target_for_namespace(namespace);
if target.is_none() {
return Shadowable::Always;
}
target.unwrap().shadowable
}
fn set_target_and_id(&mut self,
namespace: Namespace,
target: Option<Target>,
id: NodeId) {
match namespace {
TypeNS => {
self.type_target = target;
self.type_id = id;
}
ValueNS => {
self.value_target = target;
self.value_id = id;
}
}
}
}
/// The link from a module up to its nearest parent node.
#[derive(Clone,Debug)]
enum ParentLink {
NoParentLink,
ModuleParentLink(Weak<Module>, Name),
BlockParentLink(Weak<Module>, NodeId)
}
/// The type of module this is.
#[derive(Copy, PartialEq, Debug)]
enum ModuleKind {
NormalModuleKind,
TraitModuleKind,
ImplModuleKind,
EnumModuleKind,
TypeModuleKind,
AnonymousModuleKind,
}
/// One node in the tree of modules.
struct Module {
parent_link: ParentLink,
def_id: Cell<Option<DefId>>,
kind: Cell<ModuleKind>,
is_public: bool,
children: RefCell<HashMap<Name, Rc<NameBindings>>>,
imports: RefCell<Vec<ImportDirective>>,
// The external module children of this node that were declared with
// `extern crate`.
external_module_children: RefCell<HashMap<Name, Rc<Module>>>,
// The anonymous children of this node. Anonymous children are pseudo-
// modules that are implicitly created around items contained within
// blocks.
//
// For example, if we have this:
//
// fn f() {
// fn g() {
// ...
// }
// }
//
// There will be an anonymous module created around `g` with the ID of the
// entry block for `f`.
anonymous_children: RefCell<NodeMap<Rc<Module>>>,
// The status of resolving each import in this module.
import_resolutions: RefCell<HashMap<Name, ImportResolution>>,
// The number of unresolved globs that this module exports.
glob_count: Cell<uint>,
// The index of the import we're resolving.
resolved_import_count: Cell<uint>,
// Whether this module is populated. If not populated, any attempt to
// access the children must be preceded with a
// `populate_module_if_necessary` call.
populated: Cell<bool>,
}
impl Module {
fn new(parent_link: ParentLink,
def_id: Option<DefId>,
kind: ModuleKind,
external: bool,
is_public: bool)
-> Module {
Module {
parent_link: parent_link,
def_id: Cell::new(def_id),
kind: Cell::new(kind),
is_public: is_public,
children: RefCell::new(HashMap::new()),
imports: RefCell::new(Vec::new()),
external_module_children: RefCell::new(HashMap::new()),
anonymous_children: RefCell::new(NodeMap()),
import_resolutions: RefCell::new(HashMap::new()),
glob_count: Cell::new(0),
resolved_import_count: Cell::new(0),
populated: Cell::new(!external),
}
}
fn all_imports_resolved(&self) -> bool {
self.imports.borrow().len() == self.resolved_import_count.get()
}
}
impl fmt::Debug for Module {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{:?}, kind: {:?}, {}",
self.def_id,
self.kind,
if self.is_public { "public" } else { "private" } )
}
}
bitflags! {
#[derive(Debug)]
flags DefModifiers: u8 {
const PUBLIC = 0b0000_0001,
const IMPORTABLE = 0b0000_0010,
}
}
// Records a possibly-private type definition.
#[derive(Clone,Debug)]
struct TypeNsDef {
modifiers: DefModifiers, // see note in ImportResolution about how to use this
module_def: Option<Rc<Module>>,
type_def: Option<Def>,
type_span: Option<Span>
}
// Records a possibly-private value definition.
#[derive(Clone, Copy, Debug)]
struct ValueNsDef {
modifiers: DefModifiers, // see note in ImportResolution about how to use this
def: Def,
value_span: Option<Span>,
}
// Records the definitions (at most one for each namespace) that a name is
// bound to.
#[derive(Debug)]
struct NameBindings {
type_def: RefCell<Option<TypeNsDef>>, //< Meaning in type namespace.
value_def: RefCell<Option<ValueNsDef>>, //< Meaning in value namespace.
}
/// Ways in which a trait can be referenced
#[derive(Copy)]
enum TraitReferenceType {
TraitImplementation, // impl SomeTrait for T { ... }
TraitDerivation, // trait T : SomeTrait { ... }
TraitBoundingTypeParameter, // fn f<T:SomeTrait>() { ... }
TraitObject, // Box<for<'a> SomeTrait>
TraitQPath, // <T as SomeTrait>::
}
impl NameBindings {
fn new() -> NameBindings {
NameBindings {
type_def: RefCell::new(None),
value_def: RefCell::new(None),
}
}
/// Creates a new module in this set of name bindings.
fn define_module(&self,
parent_link: ParentLink,
def_id: Option<DefId>,
kind: ModuleKind,
external: bool,
is_public: bool,
sp: Span) {
// Merges the module with the existing type def or creates a new one.
let modifiers = if is_public { PUBLIC } else { DefModifiers::empty() } | IMPORTABLE;
let module_ = Rc::new(Module::new(parent_link,
def_id,
kind,
external,
is_public));
let type_def = self.type_def.borrow().clone();
match type_def {
None => {
*self.type_def.borrow_mut() = Some(TypeNsDef {
modifiers: modifiers,
module_def: Some(module_),
type_def: None,
type_span: Some(sp)
});
}
Some(type_def) => {
*self.type_def.borrow_mut() = Some(TypeNsDef {
modifiers: modifiers,
module_def: Some(module_),
type_span: Some(sp),
type_def: type_def.type_def
});
}
}
}
/// Sets the kind of the module, creating a new one if necessary.
fn set_module_kind(&self,
parent_link: ParentLink,
def_id: Option<DefId>,
kind: ModuleKind,
external: bool,
is_public: bool,
_sp: Span) {
let modifiers = if is_public { PUBLIC } else { DefModifiers::empty() } | IMPORTABLE;
let type_def = self.type_def.borrow().clone();
match type_def {
None => {
let module = Module::new(parent_link,
def_id,
kind,
external,
is_public);
*self.type_def.borrow_mut() = Some(TypeNsDef {
modifiers: modifiers,
module_def: Some(Rc::new(module)),
type_def: None,
type_span: None,
});
}
Some(type_def) => {
match type_def.module_def {
None => {
let module = Module::new(parent_link,
def_id,
kind,
external,
is_public);
*self.type_def.borrow_mut() = Some(TypeNsDef {
modifiers: modifiers,
module_def: Some(Rc::new(module)),
type_def: type_def.type_def,
type_span: None,
});
}
Some(module_def) => module_def.kind.set(kind),
}
}
}
}
/// Records a type definition.
fn define_type(&self, def: Def, sp: Span, modifiers: DefModifiers) {
debug!("defining type for def {:?} with modifiers {:?}", def, modifiers);
// Merges the type with the existing type def or creates a new one.
let type_def = self.type_def.borrow().clone();
match type_def {
None => {
*self.type_def.borrow_mut() = Some(TypeNsDef {
module_def: None,
type_def: Some(def),
type_span: Some(sp),
modifiers: modifiers,
});
}
Some(type_def) => {
*self.type_def.borrow_mut() = Some(TypeNsDef {
module_def: type_def.module_def,
type_def: Some(def),
type_span: Some(sp),
modifiers: modifiers,
});
}
}
}
/// Records a value definition.
fn define_value(&self, def: Def, sp: Span, modifiers: DefModifiers) {
debug!("defining value for def {:?} with modifiers {:?}", def, modifiers);
*self.value_def.borrow_mut() = Some(ValueNsDef {
def: def,
value_span: Some(sp),
modifiers: modifiers,
});
}
/// Returns the module node if applicable.
fn get_module_if_available(&self) -> Option<Rc<Module>> {
match *self.type_def.borrow() {
Some(ref type_def) => type_def.module_def.clone(),
None => None
}
}
/// Returns the module node. Panics if this node does not have a module
/// definition.
fn get_module(&self) -> Rc<Module> {
match self.get_module_if_available() {
None => {
panic!("get_module called on a node with no module \
definition!")
}
Some(module_def) => module_def
}
}
fn defined_in_namespace(&self, namespace: Namespace) -> bool {
match namespace {
TypeNS => return self.type_def.borrow().is_some(),
ValueNS => return self.value_def.borrow().is_some()
}
}
fn defined_in_public_namespace(&self, namespace: Namespace) -> bool {
self.defined_in_namespace_with(namespace, PUBLIC)
}
fn defined_in_namespace_with(&self, namespace: Namespace, modifiers: DefModifiers) -> bool {
match namespace {
TypeNS => match *self.type_def.borrow() {
Some(ref def) => def.modifiers.contains(modifiers), None => false
},
ValueNS => match *self.value_def.borrow() {
Some(ref def) => def.modifiers.contains(modifiers), None => false
}
}
}
fn def_for_namespace(&self, namespace: Namespace) -> Option<Def> {
match namespace {
TypeNS => {
match *self.type_def.borrow() {
None => None,
Some(ref type_def) => {
match type_def.type_def {
Some(type_def) => Some(type_def),
None => {
match type_def.module_def {
Some(ref module) => {
match module.def_id.get() {
Some(did) => Some(DefMod(did)),
None => None,
}
}
None => None,
}
}
}
}
}
}
ValueNS => {
match *self.value_def.borrow() {
None => None,
Some(value_def) => Some(value_def.def)
}
}
}
}
fn span_for_namespace(&self, namespace: Namespace) -> Option<Span> {
if self.defined_in_namespace(namespace) {
match namespace {
TypeNS => {
match *self.type_def.borrow() {
None => None,
Some(ref type_def) => type_def.type_span
}
}
ValueNS => {
match *self.value_def.borrow() {
None => None,
Some(ref value_def) => value_def.value_span
}
}
}
} else {
None
}
}
}
/// Interns the names of the primitive types.
struct PrimitiveTypeTable {
primitive_types: HashMap<Name, PrimTy>,
}
impl PrimitiveTypeTable {
fn new() -> PrimitiveTypeTable {
let mut table = PrimitiveTypeTable {
primitive_types: HashMap::new()
};
table.intern("bool", TyBool);
table.intern("char", TyChar);
table.intern("f32", TyFloat(TyF32));
table.intern("f64", TyFloat(TyF64));
table.intern("int", TyInt(TyIs(true)));
table.intern("isize", TyInt(TyIs(false)));
table.intern("i8", TyInt(TyI8));
table.intern("i16", TyInt(TyI16));
table.intern("i32", TyInt(TyI32));
table.intern("i64", TyInt(TyI64));
table.intern("str", TyStr);
table.intern("uint", TyUint(TyUs(true)));
table.intern("usize", TyUint(TyUs(false)));
table.intern("u8", TyUint(TyU8));
table.intern("u16", TyUint(TyU16));
table.intern("u32", TyUint(TyU32));
table.intern("u64", TyUint(TyU64));
table
}
fn intern(&mut self, string: &str, primitive_type: PrimTy) {
self.primitive_types.insert(token::intern(string), primitive_type);
}
}
/// The main resolver class.
struct Resolver<'a, 'tcx:'a> {
session: &'a Session,
ast_map: &'a ast_map::Map<'tcx>,
graph_root: NameBindings,
trait_item_map: FnvHashMap<(Name, DefId), TraitItemKind>,
structs: FnvHashMap<DefId, Vec<Name>>,
// The number of imports that are currently unresolved.
unresolved_imports: uint,
// The module that represents the current item scope.
current_module: Rc<Module>,
// The current set of local scopes, for values.
// FIXME #4948: Reuse ribs to avoid allocation.
value_ribs: Vec<Rib>,
// The current set of local scopes, for types.
type_ribs: Vec<Rib>,
// The current set of local scopes, for labels.
label_ribs: Vec<Rib>,
// The trait that the current context can refer to.
current_trait_ref: Option<(DefId, TraitRef)>,
// The current self type if inside an impl (used for better errors).
current_self_type: Option<Ty>,
// The ident for the keyword "self".
self_name: Name,
// The ident for the non-keyword "Self".
type_self_name: Name,
// The idents for the primitive types.
primitive_type_table: PrimitiveTypeTable,
def_map: DefMap,
freevars: RefCell<FreevarMap>,
freevars_seen: RefCell<NodeMap<NodeSet>>,
export_map: ExportMap,
trait_map: TraitMap,
external_exports: ExternalExports,
last_private: LastPrivateMap,
// Whether or not to print error messages. Can be set to true
// when getting additional info for error message suggestions,
// so as to avoid printing duplicate errors
emit_errors: bool,
make_glob_map: bool,
// Maps imports to the names of items actually imported (this actually maps
// all imports, but only glob imports are actually interesting).
glob_map: GlobMap,
used_imports: HashSet<(NodeId, Namespace)>,
used_crates: HashSet<CrateNum>,
}
#[derive(PartialEq)]
enum FallbackChecks {
Everything,
OnlyTraitAndStatics
}
impl<'a, 'tcx> Resolver<'a, 'tcx> {
fn new(session: &'a Session,
ast_map: &'a ast_map::Map<'tcx>,
crate_span: Span,
make_glob_map: MakeGlobMap) -> Resolver<'a, 'tcx> {
let graph_root = NameBindings::new();
graph_root.define_module(NoParentLink,
Some(DefId { krate: 0, node: 0 }),
NormalModuleKind,
false,
true,
crate_span);
let current_module = graph_root.get_module();
Resolver {
session: session,
ast_map: ast_map,
// The outermost module has def ID 0; this is not reflected in the
// AST.
graph_root: graph_root,
trait_item_map: FnvHashMap(),
structs: FnvHashMap(),
unresolved_imports: 0,
current_module: current_module,
value_ribs: Vec::new(),
type_ribs: Vec::new(),
label_ribs: Vec::new(),
current_trait_ref: None,
current_self_type: None,
self_name: special_names::self_,
type_self_name: special_names::type_self,
primitive_type_table: PrimitiveTypeTable::new(),
def_map: RefCell::new(NodeMap()),
freevars: RefCell::new(NodeMap()),
freevars_seen: RefCell::new(NodeMap()),
export_map: NodeMap(),
trait_map: NodeMap(),
used_imports: HashSet::new(),
used_crates: HashSet::new(),
external_exports: DefIdSet(),
last_private: NodeMap(),
emit_errors: true,
make_glob_map: make_glob_map == MakeGlobMap::Yes,
glob_map: HashMap::new(),
}
}
// Import resolution
//
// This is a fixed-point algorithm. We resolve imports until our efforts
// are stymied by an unresolved import; then we bail out of the current
// module and continue. We terminate successfully once no more imports
// remain or unsuccessfully when no forward progress in resolving imports
// is made.
/// Resolves all imports for the crate. This method performs the fixed-
/// point iteration.
fn resolve_imports(&mut self) {
let mut i = 0u;
let mut prev_unresolved_imports = 0;
loop {
debug!("(resolving imports) iteration {}, {} imports left",
i, self.unresolved_imports);
let module_root = self.graph_root.get_module();
self.resolve_imports_for_module_subtree(module_root.clone());
if self.unresolved_imports == 0 {
debug!("(resolving imports) success");
break;
}
if self.unresolved_imports == prev_unresolved_imports {
self.report_unresolved_imports(module_root);
break;
}
i += 1;
prev_unresolved_imports = self.unresolved_imports;
}
}
/// Attempts to resolve imports for the given module and all of its
/// submodules.
fn resolve_imports_for_module_subtree(&mut self, module_: Rc<Module>) {
debug!("(resolving imports for module subtree) resolving {}",
self.module_to_string(&*module_));
let orig_module = replace(&mut self.current_module, module_.clone());
self.resolve_imports_for_module(module_.clone());
self.current_module = orig_module;
build_reduced_graph::populate_module_if_necessary(self, &module_);
for (_, child_node) in module_.children.borrow().iter() {
match child_node.get_module_if_available() {
None => {
// Nothing to do.
}
Some(child_module) => {
self.resolve_imports_for_module_subtree(child_module);
}
}
}
for (_, child_module) in module_.anonymous_children.borrow().iter() {
self.resolve_imports_for_module_subtree(child_module.clone());
}
}
/// Attempts to resolve imports for the given module only.
fn resolve_imports_for_module(&mut self, module: Rc<Module>) {
if module.all_imports_resolved() {
debug!("(resolving imports for module) all imports resolved for \
{}",
self.module_to_string(&*module));
return;
}
let imports = module.imports.borrow();
let import_count = imports.len();
while module.resolved_import_count.get() < import_count {
let import_index = module.resolved_import_count.get();
let import_directive = &(*imports)[import_index];
match self.resolve_import_for_module(module.clone(),
import_directive) {
Failed(err) => {
let (span, help) = match err {
Some((span, msg)) => (span, format!(". {}", msg)),
None => (import_directive.span, String::new())
};
let msg = format!("unresolved import `{}`{}",
self.import_path_to_string(
&import_directive.module_path[],
import_directive.subclass),
help);
self.resolve_error(span, &msg[]);
}
Indeterminate => break, // Bail out. We'll come around next time.
Success(()) => () // Good. Continue.
}
module.resolved_import_count
.set(module.resolved_import_count.get() + 1);
}
}
fn names_to_string(&self, names: &[Name]) -> String {
let mut first = true;
let mut result = String::new();
for name in names.iter() {
if first {
first = false
} else {
result.push_str("::")
}
result.push_str(token::get_name(*name).get());
};
result
}
fn path_names_to_string(&self, path: &Path) -> String {
let names: Vec<ast::Name> = path.segments
.iter()
.map(|seg| seg.identifier.name)
.collect();
self.names_to_string(&names[])
}
fn import_directive_subclass_to_string(&mut self,
subclass: ImportDirectiveSubclass)
-> String {
match subclass {
SingleImport(_, source) => {
token::get_name(source).get().to_string()
}
GlobImport => "*".to_string()
}
}
fn import_path_to_string(&mut self,
names: &[Name],
subclass: ImportDirectiveSubclass)
-> String {
if names.is_empty() {
self.import_directive_subclass_to_string(subclass)
} else {
(format!("{}::{}",
self.names_to_string(names),
self.import_directive_subclass_to_string(
subclass))).to_string()
}
}
#[inline]
fn record_import_use(&mut self, import_id: NodeId, name: Name) {
if !self.make_glob_map {
return;
}
if self.glob_map.contains_key(&import_id) {
self.glob_map[import_id].insert(name);
return;
}
let mut new_set = HashSet::new();
new_set.insert(name);
self.glob_map.insert(import_id, new_set);
}
fn get_trait_name(&self, did: DefId) -> Name {
if did.krate == ast::LOCAL_CRATE {
self.ast_map.expect_item(did.node).ident.name
} else {
csearch::get_trait_name(&self.session.cstore, did)
}
}
/// Attempts to resolve the given import. The return value indicates
/// failure if we're certain the name does not exist, indeterminate if we
/// don't know whether the name exists at the moment due to other
/// currently-unresolved imports, or success if we know the name exists.
/// If successful, the resolved bindings are written into the module.
fn resolve_import_for_module(&mut self,
module_: Rc<Module>,
import_directive: &ImportDirective)
-> ResolveResult<()> {
let mut resolution_result = Failed(None);
let module_path = &import_directive.module_path;
debug!("(resolving import for module) resolving import `{}::...` in `{}`",
self.names_to_string(&module_path[]),
self.module_to_string(&*module_));
// First, resolve the module path for the directive, if necessary.
let container = if module_path.len() == 0 {
// Use the crate root.
Some((self.graph_root.get_module(), LastMod(AllPublic)))
} else {
match self.resolve_module_path(module_.clone(),
&module_path[],
DontUseLexicalScope,
import_directive.span,
ImportSearch) {
Failed(err) => {
resolution_result = Failed(err);
None
},
Indeterminate => {
resolution_result = Indeterminate;
None
}
Success(container) => Some(container),
}
};
match container {
None => {}
Some((containing_module, lp)) => {
// We found the module that the target is contained
// within. Attempt to resolve the import within it.
match import_directive.subclass {
SingleImport(target, source) => {
resolution_result =
self.resolve_single_import(&*module_,
containing_module,
target,
source,
import_directive,
lp);
}
GlobImport => {
resolution_result =
self.resolve_glob_import(&*module_,
containing_module,
import_directive,
lp);
}
}
}
}
// Decrement the count of unresolved imports.
match resolution_result {
Success(()) => {
assert!(self.unresolved_imports >= 1);
self.unresolved_imports -= 1;
}
_ => {
// Nothing to do here; just return the error.
}
}
// Decrement the count of unresolved globs if necessary. But only if
// the resolution result is indeterminate -- otherwise we'll stop
// processing imports here. (See the loop in
// resolve_imports_for_module.)
if !resolution_result.indeterminate() {
match import_directive.subclass {
GlobImport => {
assert!(module_.glob_count.get() >= 1);
module_.glob_count.set(module_.glob_count.get() - 1);
}
SingleImport(..) => {
// Ignore.
}
}
}
return resolution_result;
}
fn create_name_bindings_from_module(module: Rc<Module>) -> NameBindings {
NameBindings {
type_def: RefCell::new(Some(TypeNsDef {
modifiers: IMPORTABLE,
module_def: Some(module),
type_def: None,
type_span: None
})),
value_def: RefCell::new(None),
}
}
fn resolve_single_import(&mut self,
module_: &Module,
containing_module: Rc<Module>,
target: Name,
source: Name,
directive: &ImportDirective,
lp: LastPrivate)
-> ResolveResult<()> {
debug!("(resolving single import) resolving `{}` = `{}::{}` from \
`{}` id {}, last private {:?}",
token::get_name(target),
self.module_to_string(&*containing_module),
token::get_name(source),
self.module_to_string(module_),
directive.id,
lp);
let lp = match lp {
LastMod(lp) => lp,
LastImport {..} => {
self.session
.span_bug(directive.span,
"not expecting Import here, must be LastMod")
}
};
// We need to resolve both namespaces for this to succeed.
//
let mut value_result = UnknownResult;
let mut type_result = UnknownResult;
// Search for direct children of the containing module.
build_reduced_graph::populate_module_if_necessary(self, &containing_module);
match containing_module.children.borrow().get(&source) {
None => {
// Continue.
}
Some(ref child_name_bindings) => {
if child_name_bindings.defined_in_namespace(ValueNS) {
debug!("(resolving single import) found value binding");
value_result = BoundResult(containing_module.clone(),
(*child_name_bindings).clone());
}
if child_name_bindings.defined_in_namespace(TypeNS) {
debug!("(resolving single import) found type binding");
type_result = BoundResult(containing_module.clone(),
(*child_name_bindings).clone());
}
}
}
// Unless we managed to find a result in both namespaces (unlikely),
// search imports as well.
let mut value_used_reexport = false;
let mut type_used_reexport = false;
match (value_result.clone(), type_result.clone()) {
(BoundResult(..), BoundResult(..)) => {} // Continue.
_ => {
// If there is an unresolved glob at this point in the
// containing module, bail out. We don't know enough to be
// able to resolve this import.
if containing_module.glob_count.get() > 0 {
debug!("(resolving single import) unresolved glob; \
bailing out");
return Indeterminate;
}
// Now search the exported imports within the containing module.
match containing_module.import_resolutions.borrow().get(&source) {
None => {
debug!("(resolving single import) no import");
// The containing module definitely doesn't have an
// exported import with the name in question. We can
// therefore accurately report that the names are
// unbound.
if value_result.is_unknown() {
value_result = UnboundResult;
}
if type_result.is_unknown() {
type_result = UnboundResult;
}
}
Some(import_resolution)
if import_resolution.outstanding_references == 0 => {
fn get_binding(this: &mut Resolver,
import_resolution: &ImportResolution,
namespace: Namespace,
source: &Name)
-> NamespaceResult {
// Import resolutions must be declared with "pub"
// in order to be exported.
if !import_resolution.is_public {
return UnboundResult;
}
match import_resolution.
target_for_namespace(namespace) {
None => {
return UnboundResult;
}
Some(Target {
target_module,
bindings,
shadowable: _
}) => {
debug!("(resolving single import) found \
import in ns {:?}", namespace);
let id = import_resolution.id(namespace);
// track used imports and extern crates as well
this.used_imports.insert((id, namespace));
this.record_import_use(id, *source);
match target_module.def_id.get() {
Some(DefId{krate: kid, ..}) => {
this.used_crates.insert(kid);
},
_ => {}
}
return BoundResult(target_module, bindings);
}
}
}
// The name is an import which has been fully
// resolved. We can, therefore, just follow it.
if value_result.is_unknown() {
value_result = get_binding(self,
import_resolution,
ValueNS,
&source);
value_used_reexport = import_resolution.is_public;
}
if type_result.is_unknown() {
type_result = get_binding(self,
import_resolution,
TypeNS,
&source);
type_used_reexport = import_resolution.is_public;
}
}
Some(_) => {
// If containing_module is the same module whose import we are resolving
// and there it has an unresolved import with the same name as `source`,
// then the user is actually trying to import an item that is declared
// in the same scope
//
// e.g
// use self::submodule;
// pub mod submodule;
//
// In this case we continue as if we resolved the import and let the
// check_for_conflicts_between_imports_and_items call below handle
// the conflict
match (module_.def_id.get(), containing_module.def_id.get()) {
(Some(id1), Some(id2)) if id1 == id2 => {
if value_result.is_unknown() {
value_result = UnboundResult;
}
if type_result.is_unknown() {
type_result = UnboundResult;
}
}
_ => {
// The import is unresolved. Bail out.
debug!("(resolving single import) unresolved import; \
bailing out");
return Indeterminate;
}
}
}
}
}
}
// If we didn't find a result in the type namespace, search the
// external modules.
let mut value_used_public = false;
let mut type_used_public = false;
match type_result {
BoundResult(..) => {}
_ => {
match containing_module.external_module_children.borrow_mut()
.get(&source).cloned() {
None => {} // Continue.
Some(module) => {
debug!("(resolving single import) found external \
module");
// track the module as used.
match module.def_id.get() {
Some(DefId{krate: kid, ..}) => { self.used_crates.insert(kid); },
_ => {}
}
let name_bindings =
Rc::new(Resolver::create_name_bindings_from_module(
module));
type_result = BoundResult(containing_module.clone(),
name_bindings);
type_used_public = true;
}
}
}
}
// We've successfully resolved the import. Write the results in.
let mut import_resolutions = module_.import_resolutions.borrow_mut();
let import_resolution = &mut (*import_resolutions)[target];
{
let mut check_and_write_import = |&mut: namespace, result: &_, used_public: &mut bool| {
let namespace_name = match namespace {
TypeNS => "type",
ValueNS => "value",
};
match *result {
BoundResult(ref target_module, ref name_bindings) => {
debug!("(resolving single import) found {:?} target: {:?}",
namespace_name,
name_bindings.def_for_namespace(namespace));
self.check_for_conflicting_import(
&import_resolution.target_for_namespace(namespace),
directive.span,
target,
namespace);
self.check_that_import_is_importable(
&**name_bindings,
directive.span,
target,
namespace);
let target = Some(Target::new(target_module.clone(),
name_bindings.clone(),
directive.shadowable));
import_resolution.set_target_and_id(namespace, target, directive.id);
import_resolution.is_public = directive.is_public;
*used_public = name_bindings.defined_in_public_namespace(namespace);
}
UnboundResult => { /* Continue. */ }
UnknownResult => {
panic!("{:?} result should be known at this point", namespace_name);
}
}
};
check_and_write_import(ValueNS, &value_result, &mut value_used_public);
check_and_write_import(TypeNS, &type_result, &mut type_used_public);
}
self.check_for_conflicts_between_imports_and_items(
module_,
import_resolution,
directive.span,
target);
if value_result.is_unbound() && type_result.is_unbound() {
let msg = format!("There is no `{}` in `{}`",
token::get_name(source),
self.module_to_string(&*containing_module));
return Failed(Some((directive.span, msg)));
}
let value_used_public = value_used_reexport || value_used_public;
let type_used_public = type_used_reexport || type_used_public;
assert!(import_resolution.outstanding_references >= 1);
import_resolution.outstanding_references -= 1;
// record what this import resolves to for later uses in documentation,
// this may resolve to either a value or a type, but for documentation
// purposes it's good enough to just favor one over the other.
let value_private = match import_resolution.value_target {
Some(ref target) => {
let def = target.bindings.def_for_namespace(ValueNS).unwrap();
self.def_map.borrow_mut().insert(directive.id, def);
let did = def.def_id();
if value_used_public {Some(lp)} else {Some(DependsOn(did))}
},
// AllPublic here and below is a dummy value, it should never be used because
// _exists is false.
None => None,
};
let type_private = match import_resolution.type_target {
Some(ref target) => {
let def = target.bindings.def_for_namespace(TypeNS).unwrap();
self.def_map.borrow_mut().insert(directive.id, def);
let did = def.def_id();
if type_used_public {Some(lp)} else {Some(DependsOn(did))}
},
None => None,
};
self.last_private.insert(directive.id, LastImport{value_priv: value_private,
value_used: Used,
type_priv: type_private,
type_used: Used});
debug!("(resolving single import) successfully resolved import");
return Success(());
}
// Resolves a glob import. Note that this function cannot fail; it either
// succeeds or bails out (as importing * from an empty module or a module
// that exports nothing is valid). containing_module is the module we are
// actually importing, i.e., `foo` in `use foo::*`.
fn resolve_glob_import(&mut self,
module_: &Module,
containing_module: Rc<Module>,
import_directive: &ImportDirective,
lp: LastPrivate)
-> ResolveResult<()> {
let id = import_directive.id;
let is_public = import_directive.is_public;
// This function works in a highly imperative manner; it eagerly adds
// everything it can to the list of import resolutions of the module
// node.
debug!("(resolving glob import) resolving glob import {}", id);
// We must bail out if the node has unresolved imports of any kind
// (including globs).
if !(*containing_module).all_imports_resolved() {
debug!("(resolving glob import) target module has unresolved \
imports; bailing out");
return Indeterminate;
}
assert_eq!(containing_module.glob_count.get(), 0);
// Add all resolved imports from the containing module.
let import_resolutions = containing_module.import_resolutions.borrow();
for (ident, target_import_resolution) in import_resolutions.iter() {
debug!("(resolving glob import) writing module resolution \
{} into `{}`",
token::get_name(*ident),
self.module_to_string(module_));
if !target_import_resolution.is_public {
debug!("(resolving glob import) nevermind, just kidding");
continue
}
// Here we merge two import resolutions.
let mut import_resolutions = module_.import_resolutions.borrow_mut();
match import_resolutions.get_mut(ident) {
Some(dest_import_resolution) => {
// Merge the two import resolutions at a finer-grained
// level.
match target_import_resolution.value_target {
None => {
// Continue.
}
Some(ref value_target) => {
self.check_for_conflicting_import(&dest_import_resolution.value_target,
import_directive.span,
*ident,
ValueNS);
dest_import_resolution.value_target = Some(value_target.clone());
}
}
match target_import_resolution.type_target {
None => {
// Continue.
}
Some(ref type_target) => {
self.check_for_conflicting_import(&dest_import_resolution.type_target,
import_directive.span,
*ident,
TypeNS);
dest_import_resolution.type_target = Some(type_target.clone());
}
}
dest_import_resolution.is_public = is_public;
continue;
}
None => {}
}
// Simple: just copy the old import resolution.
let mut new_import_resolution = ImportResolution::new(id, is_public);
new_import_resolution.value_target =
target_import_resolution.value_target.clone();
new_import_resolution.type_target =
target_import_resolution.type_target.clone();
import_resolutions.insert(*ident, new_import_resolution);
}
// Add all children from the containing module.
build_reduced_graph::populate_module_if_necessary(self, &containing_module);
for (&name, name_bindings) in containing_module.children.borrow().iter() {
self.merge_import_resolution(module_,
containing_module.clone(),
import_directive,
name,
name_bindings.clone());
}
// Add external module children from the containing module.
for (&name, module) in containing_module.external_module_children.borrow().iter() {
let name_bindings =
Rc::new(Resolver::create_name_bindings_from_module(module.clone()));
self.merge_import_resolution(module_,
containing_module.clone(),
import_directive,
name,
name_bindings);
}
// Record the destination of this import
match containing_module.def_id.get() {
Some(did) => {
self.def_map.borrow_mut().insert(id, DefMod(did));
self.last_private.insert(id, lp);
}
None => {}
}
debug!("(resolving glob import) successfully resolved import");
return Success(());
}
fn merge_import_resolution(&mut self,
module_: &Module,
containing_module: Rc<Module>,
import_directive: &ImportDirective,
name: Name,
name_bindings: Rc<NameBindings>) {
let id = import_directive.id;
let is_public = import_directive.is_public;
let mut import_resolutions = module_.import_resolutions.borrow_mut();
let dest_import_resolution = import_resolutions.entry(name).get().unwrap_or_else(
|vacant_entry| {
// Create a new import resolution from this child.
vacant_entry.insert(ImportResolution::new(id, is_public))
});
debug!("(resolving glob import) writing resolution `{}` in `{}` \
to `{}`",
token::get_name(name).get(),
self.module_to_string(&*containing_module),
self.module_to_string(module_));
// Merge the child item into the import resolution.
{
let mut merge_child_item = |&mut : namespace| {
if name_bindings.defined_in_namespace_with(namespace, IMPORTABLE | PUBLIC) {
let namespace_name = match namespace {
TypeNS => "type",
ValueNS => "value",
};
debug!("(resolving glob import) ... for {} target", namespace_name);
if dest_import_resolution.shadowable(namespace) == Shadowable::Never {
let msg = format!("a {} named `{}` has already been imported \
in this module",
namespace_name,
token::get_name(name).get());
span_err!(self.session, import_directive.span, E0251, "{}", msg.as_slice());
} else {
let target = Target::new(containing_module.clone(),
name_bindings.clone(),
import_directive.shadowable);
dest_import_resolution.set_target_and_id(namespace,
Some(target),
id);
}
}
};
merge_child_item(ValueNS);
merge_child_item(TypeNS);
}
dest_import_resolution.is_public = is_public;
self.check_for_conflicts_between_imports_and_items(
module_,
dest_import_resolution,
import_directive.span,
name);
}
/// Checks that imported names and items don't have the same name.
fn check_for_conflicting_import(&mut self,
target: &Option<Target>,
import_span: Span,
name: Name,
namespace: Namespace) {
debug!("check_for_conflicting_import: {}; target exists: {}",
token::get_name(name).get(),
target.is_some());
match *target {
Some(ref target) if target.shadowable != Shadowable::Always => {
let msg = format!("a {} named `{}` has already been imported \
in this module",
match namespace {
TypeNS => "type",
ValueNS => "value",
},
token::get_name(name).get());
span_err!(self.session, import_span, E0252, "{}", &msg[]);
}
Some(_) | None => {}
}
}
/// Checks that an import is actually importable
fn check_that_import_is_importable(&mut self,
name_bindings: &NameBindings,
import_span: Span,
name: Name,
namespace: Namespace) {
if !name_bindings.defined_in_namespace_with(namespace, IMPORTABLE) {
let msg = format!("`{}` is not directly importable",
token::get_name(name));
span_err!(self.session, import_span, E0253, "{}", &msg[]);
}
}
/// Checks that imported names and items don't have the same name.
fn check_for_conflicts_between_imports_and_items(&mut self,
module: &Module,
import_resolution:
&ImportResolution,
import_span: Span,
name: Name) {
// First, check for conflicts between imports and `extern crate`s.
if module.external_module_children
.borrow()
.contains_key(&name) {
match import_resolution.type_target {
Some(ref target) if target.shadowable != Shadowable::Always => {
let msg = format!("import `{0}` conflicts with imported \
crate in this module \
(maybe you meant `use {0}::*`?)",
token::get_name(name).get());
span_err!(self.session, import_span, E0254, "{}", &msg[]);
}
Some(_) | None => {}
}
}
// Check for item conflicts.
let children = module.children.borrow();
let name_bindings = match children.get(&name) {
None => {
// There can't be any conflicts.
return
}
Some(ref name_bindings) => (*name_bindings).clone(),
};
match import_resolution.value_target {
Some(ref target) if target.shadowable != Shadowable::Always => {
if let Some(ref value) = *name_bindings.value_def.borrow() {
let msg = format!("import `{}` conflicts with value \
in this module",
token::get_name(name).get());
span_err!(self.session, import_span, E0255, "{}", &msg[]);
if let Some(span) = value.value_span {
self.session.span_note(span,
"conflicting value here");
}
}
}
Some(_) | None => {}
}
match import_resolution.type_target {
Some(ref target) if target.shadowable != Shadowable::Always => {
if let Some(ref ty) = *name_bindings.type_def.borrow() {
match ty.module_def {
None => {
let msg = format!("import `{}` conflicts with type in \
this module",
token::get_name(name).get());
span_err!(self.session, import_span, E0256, "{}", &msg[]);
if let Some(span) = ty.type_span {
self.session.span_note(span,
"note conflicting type here")
}
}
Some(ref module_def) => {
match module_def.kind.get() {
ImplModuleKind => {
if let Some(span) = ty.type_span {
let msg = format!("inherent implementations \
are only allowed on types \
defined in the current module");
span_err!(self.session, span, E0257, "{}", &msg[]);
self.session.span_note(import_span,
"import from other module here")
}
}
_ => {
let msg = format!("import `{}` conflicts with existing \
submodule",
token::get_name(name).get());
span_err!(self.session, import_span, E0258, "{}", &msg[]);
if let Some(span) = ty.type_span {
self.session.span_note(span,
"note conflicting module here")
}
}
}
}
}
}
}
Some(_) | None => {}
}
}
/// Checks that the names of external crates don't collide with other
/// external crates.
fn check_for_conflicts_between_external_crates(&self,
module: &Module,
name: Name,
span: Span) {
if module.external_module_children.borrow().contains_key(&name) {
span_err!(self.session, span, E0259,
"an external crate named `{}` has already \
been imported into this module",
token::get_name(name).get());
}
}
/// Checks that the names of items don't collide with external crates.
fn check_for_conflicts_between_external_crates_and_items(&self,
module: &Module,
name: Name,
span: Span) {
if module.external_module_children.borrow().contains_key(&name) {
span_err!(self.session, span, E0260,
"the name `{}` conflicts with an external \
crate that has been imported into this \
module",
token::get_name(name).get());
}
}
/// Resolves the given module path from the given root `module_`.
fn resolve_module_path_from_root(&mut self,
module_: Rc<Module>,
module_path: &[Name],
index: uint,
span: Span,
name_search_type: NameSearchType,
lp: LastPrivate)
-> ResolveResult<(Rc<Module>, LastPrivate)> {
fn search_parent_externals(needle: Name, module: &Rc<Module>)
-> Option<Rc<Module>> {
module.external_module_children.borrow()
.get(&needle).cloned()
.map(|_| module.clone())
.or_else(|| {
match module.parent_link.clone() {
ModuleParentLink(parent, _) => {
search_parent_externals(needle,
&parent.upgrade().unwrap())
}
_ => None
}
})
}
let mut search_module = module_;
let mut index = index;
let module_path_len = module_path.len();
let mut closest_private = lp;
// Resolve the module part of the path. This does not involve looking
// upward though scope chains; we simply resolve names directly in
// modules as we go.
while index < module_path_len {
let name = module_path[index];
match self.resolve_name_in_module(search_module.clone(),
name,
TypeNS,
name_search_type,
false) {
Failed(None) => {
let segment_name = token::get_name(name);
let module_name = self.module_to_string(&*search_module);
let mut span = span;
let msg = if "???" == &module_name[] {
span.hi = span.lo + Pos::from_usize(segment_name.get().len());
match search_parent_externals(name,
&self.current_module) {
Some(module) => {
let path_str = self.names_to_string(module_path);
let target_mod_str = self.module_to_string(&*module);
let current_mod_str =
self.module_to_string(&*self.current_module);
let prefix = if target_mod_str == current_mod_str {
"self::".to_string()
} else {
format!("{}::", target_mod_str)
};
format!("Did you mean `{}{}`?", prefix, path_str)
},
None => format!("Maybe a missing `extern crate {}`?",
segment_name),
}
} else {
format!("Could not find `{}` in `{}`",
segment_name,
module_name)
};
return Failed(Some((span, msg)));
}
Failed(err) => return Failed(err),
Indeterminate => {
debug!("(resolving module path for import) module \
resolution is indeterminate: {}",
token::get_name(name));
return Indeterminate;
}
Success((target, used_proxy)) => {
// Check to see whether there are type bindings, and, if
// so, whether there is a module within.
match *target.bindings.type_def.borrow() {
Some(ref type_def) => {
match type_def.module_def {
None => {
let msg = format!("Not a module `{}`",
token::get_name(name));
return Failed(Some((span, msg)));
}
Some(ref module_def) => {
search_module = module_def.clone();
// track extern crates for unused_extern_crate lint
if let Some(did) = module_def.def_id.get() {
self.used_crates.insert(did.krate);
}
// Keep track of the closest
// private module used when
// resolving this import chain.
if !used_proxy && !search_module.is_public {
if let Some(did) = search_module.def_id.get() {
closest_private = LastMod(DependsOn(did));
}
}
}
}
}
None => {
// There are no type bindings at all.
let msg = format!("Not a module `{}`",
token::get_name(name));
return Failed(Some((span, msg)));
}
}
}
}
index += 1;
}
return Success((search_module, closest_private));
}
/// Attempts to resolve the module part of an import directive or path
/// rooted at the given module.
///
/// On success, returns the resolved module, and the closest *private*
/// module found to the destination when resolving this path.
fn resolve_module_path(&mut self,
module_: Rc<Module>,
module_path: &[Name],
use_lexical_scope: UseLexicalScopeFlag,
span: Span,
name_search_type: NameSearchType)
-> ResolveResult<(Rc<Module>, LastPrivate)> {
let module_path_len = module_path.len();
assert!(module_path_len > 0);
debug!("(resolving module path for import) processing `{}` rooted at `{}`",
self.names_to_string(module_path),
self.module_to_string(&*module_));
// Resolve the module prefix, if any.
let module_prefix_result = self.resolve_module_prefix(module_.clone(),
module_path);
let search_module;
let start_index;
let last_private;
match module_prefix_result {
Failed(None) => {
let mpath = self.names_to_string(module_path);
let mpath = &mpath[];
match mpath.rfind(':') {
Some(idx) => {
let msg = format!("Could not find `{}` in `{}`",
// idx +- 1 to account for the
// colons on either side
&mpath[idx + 1..],
&mpath[..idx - 1]);
return Failed(Some((span, msg)));
},
None => {
return Failed(None)
}
}
}
Failed(err) => return Failed(err),
Indeterminate => {
debug!("(resolving module path for import) indeterminate; \
bailing");
return Indeterminate;
}
Success(NoPrefixFound) => {
// There was no prefix, so we're considering the first element
// of the path. How we handle this depends on whether we were
// instructed to use lexical scope or not.
match use_lexical_scope {
DontUseLexicalScope => {
// This is a crate-relative path. We will start the
// resolution process at index zero.
search_module = self.graph_root.get_module();
start_index = 0;
last_private = LastMod(AllPublic);
}
UseLexicalScope => {
// This is not a crate-relative path. We resolve the
// first component of the path in the current lexical
// scope and then proceed to resolve below that.
match self.resolve_module_in_lexical_scope(module_,
module_path[0]) {
Failed(err) => return Failed(err),
Indeterminate => {
debug!("(resolving module path for import) \
indeterminate; bailing");
return Indeterminate;
}
Success(containing_module) => {
search_module = containing_module;
start_index = 1;
last_private = LastMod(AllPublic);
}
}
}
}
}
Success(PrefixFound(ref containing_module, index)) => {
search_module = containing_module.clone();
start_index = index;
last_private = LastMod(DependsOn(containing_module.def_id
.get()
.unwrap()));
}
}
self.resolve_module_path_from_root(search_module,
module_path,
start_index,
span,
name_search_type,
last_private)
}
/// Invariant: This must only be called during main resolution, not during
/// import resolution.
fn resolve_item_in_lexical_scope(&mut self,
module_: Rc<Module>,
name: Name,
namespace: Namespace)
-> ResolveResult<(Target, bool)> {
debug!("(resolving item in lexical scope) resolving `{}` in \
namespace {:?} in `{}`",
token::get_name(name),
namespace,
self.module_to_string(&*module_));
// The current module node is handled specially. First, check for
// its immediate children.
build_reduced_graph::populate_module_if_necessary(self, &module_);
match module_.children.borrow().get(&name) {
Some(name_bindings)
if name_bindings.defined_in_namespace(namespace) => {
debug!("top name bindings succeeded");
return Success((Target::new(module_.clone(),
name_bindings.clone(),
Shadowable::Never),
false));
}
Some(_) | None => { /* Not found; continue. */ }
}
// Now check for its import directives. We don't have to have resolved
// all its imports in the usual way; this is because chains of
// adjacent import statements are processed as though they mutated the
// current scope.
if let Some(import_resolution) = module_.import_resolutions.borrow().get(&name) {
match (*import_resolution).target_for_namespace(namespace) {
None => {
// Not found; continue.
debug!("(resolving item in lexical scope) found \
import resolution, but not in namespace {:?}",
namespace);
}
Some(target) => {
debug!("(resolving item in lexical scope) using \
import resolution");
// track used imports and extern crates as well
let id = import_resolution.id(namespace);
self.used_imports.insert((id, namespace));
self.record_import_use(id, name);
if let Some(DefId{krate: kid, ..}) = target.target_module.def_id.get() {
self.used_crates.insert(kid);
}
return Success((target, false));
}
}
}
// Search for external modules.
if namespace == TypeNS {
if let Some(module) = module_.external_module_children.borrow().get(&name).cloned() {
let name_bindings =
Rc::new(Resolver::create_name_bindings_from_module(module));
debug!("lower name bindings succeeded");
return Success((Target::new(module_,
name_bindings,
Shadowable::Never),
false));
}
}
// Finally, proceed up the scope chain looking for parent modules.
let mut search_module = module_;
loop {
// Go to the next parent.
match search_module.parent_link.clone() {
NoParentLink => {
// No more parents. This module was unresolved.
debug!("(resolving item in lexical scope) unresolved \
module");
return Failed(None);
}
ModuleParentLink(parent_module_node, _) => {
match search_module.kind.get() {
NormalModuleKind => {
// We stop the search here.
debug!("(resolving item in lexical \
scope) unresolved module: not \
searching through module \
parents");
return Failed(None);
}
TraitModuleKind |
ImplModuleKind |
EnumModuleKind |
TypeModuleKind |
AnonymousModuleKind => {
search_module = parent_module_node.upgrade().unwrap();
}
}
}
BlockParentLink(ref parent_module_node, _) => {
search_module = parent_module_node.upgrade().unwrap();
}
}
// Resolve the name in the parent module.
match self.resolve_name_in_module(search_module.clone(),
name,
namespace,
PathSearch,
true) {
Failed(Some((span, msg))) =>
self.resolve_error(span, &format!("failed to resolve. {}",
msg)[]),
Failed(None) => (), // Continue up the search chain.
Indeterminate => {
// We couldn't see through the higher scope because of an
// unresolved import higher up. Bail.
debug!("(resolving item in lexical scope) indeterminate \
higher scope; bailing");
return Indeterminate;
}
Success((target, used_reexport)) => {
// We found the module.
debug!("(resolving item in lexical scope) found name \
in module, done");
return Success((target, used_reexport));
}
}
}
}
/// Resolves a module name in the current lexical scope.
fn resolve_module_in_lexical_scope(&mut self,
module_: Rc<Module>,
name: Name)
-> ResolveResult<Rc<Module>> {
// If this module is an anonymous module, resolve the item in the
// lexical scope. Otherwise, resolve the item from the crate root.
let resolve_result = self.resolve_item_in_lexical_scope(module_, name, TypeNS);
match resolve_result {
Success((target, _)) => {
let bindings = &*target.bindings;
match *bindings.type_def.borrow() {
Some(ref type_def) => {
match type_def.module_def {
None => {
debug!("!!! (resolving module in lexical \
scope) module wasn't actually a \
module!");
return Failed(None);
}
Some(ref module_def) => {
return Success(module_def.clone());
}
}
}
None => {
debug!("!!! (resolving module in lexical scope) module
wasn't actually a module!");
return Failed(None);
}
}
}
Indeterminate => {
debug!("(resolving module in lexical scope) indeterminate; \
bailing");
return Indeterminate;
}
Failed(err) => {
debug!("(resolving module in lexical scope) failed to resolve");
return Failed(err);
}
}
}
/// Returns the nearest normal module parent of the given module.
fn get_nearest_normal_module_parent(&mut self, module_: Rc<Module>)
-> Option<Rc<Module>> {
let mut module_ = module_;
loop {
match module_.parent_link.clone() {
NoParentLink => return None,
ModuleParentLink(new_module, _) |
BlockParentLink(new_module, _) => {
let new_module = new_module.upgrade().unwrap();
match new_module.kind.get() {
NormalModuleKind => return Some(new_module),
TraitModuleKind |
ImplModuleKind |
EnumModuleKind |
TypeModuleKind |
AnonymousModuleKind => module_ = new_module,
}
}
}
}
}
/// Returns the nearest normal module parent of the given module, or the
/// module itself if it is a normal module.
fn get_nearest_normal_module_parent_or_self(&mut self, module_: Rc<Module>)
-> Rc<Module> {
match module_.kind.get() {
NormalModuleKind => return module_,
TraitModuleKind |
ImplModuleKind |
EnumModuleKind |
TypeModuleKind |
AnonymousModuleKind => {
match self.get_nearest_normal_module_parent(module_.clone()) {
None => module_,
Some(new_module) => new_module
}
}
}
}
/// Resolves a "module prefix". A module prefix is one or both of (a) `self::`;
/// (b) some chain of `super::`.
/// grammar: (SELF MOD_SEP ) ? (SUPER MOD_SEP) *
fn resolve_module_prefix(&mut self,
module_: Rc<Module>,
module_path: &[Name])
-> ResolveResult<ModulePrefixResult> {
// Start at the current module if we see `self` or `super`, or at the
// top of the crate otherwise.
let mut containing_module;
let mut i;
let first_module_path_string = token::get_name(module_path[0]);
if "self" == first_module_path_string.get() {
containing_module =
self.get_nearest_normal_module_parent_or_self(module_);
i = 1;
} else if "super" == first_module_path_string.get() {
containing_module =
self.get_nearest_normal_module_parent_or_self(module_);
i = 0; // We'll handle `super` below.
} else {
return Success(NoPrefixFound);
}
// Now loop through all the `super`s we find.
while i < module_path.len() {
let string = token::get_name(module_path[i]);
if "super" != string.get() {
break
}
debug!("(resolving module prefix) resolving `super` at {}",
self.module_to_string(&*containing_module));
match self.get_nearest_normal_module_parent(containing_module) {
None => return Failed(None),
Some(new_module) => {
containing_module = new_module;
i += 1;
}
}
}
debug!("(resolving module prefix) finished resolving prefix at {}",
self.module_to_string(&*containing_module));
return Success(PrefixFound(containing_module, i));
}
/// Attempts to resolve the supplied name in the given module for the
/// given namespace. If successful, returns the target corresponding to
/// the name.
///
/// The boolean returned on success is an indicator of whether this lookup
/// passed through a public re-export proxy.
fn resolve_name_in_module(&mut self,
module_: Rc<Module>,
name: Name,
namespace: Namespace,
name_search_type: NameSearchType,
allow_private_imports: bool)
-> ResolveResult<(Target, bool)> {
debug!("(resolving name in module) resolving `{}` in `{}`",
token::get_name(name).get(),
self.module_to_string(&*module_));
// First, check the direct children of the module.
build_reduced_graph::populate_module_if_necessary(self, &module_);
match module_.children.borrow().get(&name) {
Some(name_bindings)
if name_bindings.defined_in_namespace(namespace) => {
debug!("(resolving name in module) found node as child");
return Success((Target::new(module_.clone(),
name_bindings.clone(),
Shadowable::Never),
false));
}
Some(_) | None => {
// Continue.
}
}
// Next, check the module's imports if necessary.
// If this is a search of all imports, we should be done with glob
// resolution at this point.
if name_search_type == PathSearch {
assert_eq!(module_.glob_count.get(), 0);
}
// Check the list of resolved imports.
match module_.import_resolutions.borrow().get(&name) {
Some(import_resolution) if allow_private_imports ||
import_resolution.is_public => {
if import_resolution.is_public &&
import_resolution.outstanding_references != 0 {
debug!("(resolving name in module) import \
unresolved; bailing out");
return Indeterminate;
}
match import_resolution.target_for_namespace(namespace) {
None => {
debug!("(resolving name in module) name found, \
but not in namespace {:?}",
namespace);
}
Some(target) => {
debug!("(resolving name in module) resolved to \
import");
// track used imports and extern crates as well
let id = import_resolution.id(namespace);
self.used_imports.insert((id, namespace));
self.record_import_use(id, name);
if let Some(DefId{krate: kid, ..}) = target.target_module.def_id.get() {
self.used_crates.insert(kid);
}
return Success((target, true));
}
}
}
Some(..) | None => {} // Continue.
}
// Finally, search through external children.
if namespace == TypeNS {
if let Some(module) = module_.external_module_children.borrow().get(&name).cloned() {
let name_bindings =
Rc::new(Resolver::create_name_bindings_from_module(module));
return Success((Target::new(module_,
name_bindings,
Shadowable::Never),
false));
}
}
// We're out of luck.
debug!("(resolving name in module) failed to resolve `{}`",
token::get_name(name).get());
return Failed(None);
}
fn report_unresolved_imports(&mut self, module_: Rc<Module>) {
let index = module_.resolved_import_count.get();
let imports = module_.imports.borrow();
let import_count = imports.len();
if index != import_count {
let sn = self.session
.codemap()
.span_to_snippet((*imports)[index].span)
.unwrap();
if sn.contains("::") {
self.resolve_error((*imports)[index].span,
"unresolved import");
} else {
let err = format!("unresolved import (maybe you meant `{}::*`?)",
sn);
self.resolve_error((*imports)[index].span, &err[]);
}
}
// Descend into children and anonymous children.
build_reduced_graph::populate_module_if_necessary(self, &module_);
for (_, child_node) in module_.children.borrow().iter() {
match child_node.get_module_if_available() {
None => {
// Continue.
}
Some(child_module) => {
self.report_unresolved_imports(child_module);
}
}
}
for (_, module_) in module_.anonymous_children.borrow().iter() {
self.report_unresolved_imports(module_.clone());
}
}
// AST resolution
//
// We maintain a list of value ribs and type ribs.
//
// Simultaneously, we keep track of the current position in the module
// graph in the `current_module` pointer. When we go to resolve a name in
// the value or type namespaces, we first look through all the ribs and
// then query the module graph. When we resolve a name in the module
// namespace, we can skip all the ribs (since nested modules are not
// allowed within blocks in Rust) and jump straight to the current module
// graph node.
//
// Named implementations are handled separately. When we find a method
// call, we consult the module node to find all of the implementations in
// scope. This information is lazily cached in the module node. We then
// generate a fake "implementation scope" containing all the
// implementations thus found, for compatibility with old resolve pass.
fn with_scope<F>(&mut self, name: Option<Name>, f: F) where
F: FnOnce(&mut Resolver),
{
let orig_module = self.current_module.clone();
// Move down in the graph.
match name {
None => {
// Nothing to do.
}
Some(name) => {
build_reduced_graph::populate_module_if_necessary(self, &orig_module);
match orig_module.children.borrow().get(&name) {
None => {
debug!("!!! (with scope) didn't find `{}` in `{}`",
token::get_name(name),
self.module_to_string(&*orig_module));
}
Some(name_bindings) => {
match (*name_bindings).get_module_if_available() {
None => {
debug!("!!! (with scope) didn't find module \
for `{}` in `{}`",
token::get_name(name),
self.module_to_string(&*orig_module));
}
Some(module_) => {
self.current_module = module_;
}
}
}
}
}
}
f(self);
self.current_module = orig_module;
}
/// Wraps the given definition in the appropriate number of `DefUpvar`
/// wrappers.
fn upvarify(&self,
ribs: &[Rib],
def_like: DefLike,
span: Span)
-> Option<DefLike> {
match def_like {
DlDef(d @ DefUpvar(..)) => {
self.session.span_bug(span,
&format!("unexpected {:?} in bindings", d)[])
}
DlDef(d @ DefLocal(_)) => {
let node_id = d.def_id().node;
let mut def = d;
for rib in ribs.iter() {
match rib.kind {
NormalRibKind => {
// Nothing to do. Continue.
}
ClosureRibKind(function_id) => {
let prev_def = def;
def = DefUpvar(node_id, function_id);
let mut seen = self.freevars_seen.borrow_mut();
let seen = match seen.entry(function_id) {
Occupied(v) => v.into_mut(),
Vacant(v) => v.insert(NodeSet()),
};
if seen.contains(&node_id) {
continue;
}
match self.freevars.borrow_mut().entry(function_id) {
Occupied(v) => v.into_mut(),
Vacant(v) => v.insert(vec![]),
}.push(Freevar { def: prev_def, span: span });
seen.insert(node_id);
}
MethodRibKind(item_id, _) => {
// If the def is a ty param, and came from the parent
// item, it's ok
match def {
DefTyParam(_, _, did, _) if {
self.def_map.borrow().get(&did.node).cloned()
== Some(DefTyParamBinder(item_id))
} => {} // ok
DefSelfTy(did) if did == item_id => {} // ok
_ => {
// This was an attempt to access an upvar inside a
// named function item. This is not allowed, so we
// report an error.
self.resolve_error(
span,
"can't capture dynamic environment in a fn item; \
use the || { ... } closure form instead");
return None;
}
}
}
ItemRibKind => {
// This was an attempt to access an upvar inside a
// named function item. This is not allowed, so we
// report an error.
self.resolve_error(
span,
"can't capture dynamic environment in a fn item; \
use the || { ... } closure form instead");
return None;
}
ConstantItemRibKind => {
// Still doesn't deal with upvars
self.resolve_error(span,
"attempt to use a non-constant \
value in a constant");
}
}
}
Some(DlDef(def))
}
DlDef(def @ DefTyParam(..)) |
DlDef(def @ DefSelfTy(..)) => {
for rib in ribs.iter() {
match rib.kind {
NormalRibKind | ClosureRibKind(..) => {
// Nothing to do. Continue.
}
MethodRibKind(item_id, _) => {
// If the def is a ty param, and came from the parent
// item, it's ok
match def {
DefTyParam(_, _, did, _) if {
self.def_map.borrow().get(&did.node).cloned()
== Some(DefTyParamBinder(item_id))
} => {} // ok
DefSelfTy(did) if did == item_id => {} // ok
_ => {
// This was an attempt to use a type parameter outside
// its scope.
self.resolve_error(span,
"can't use type parameters from \
outer function; try using a local \
type parameter instead");
return None;
}
}
}
ItemRibKind => {
// This was an attempt to use a type parameter outside
// its scope.
self.resolve_error(span,
"can't use type parameters from \
outer function; try using a local \
type parameter instead");
return None;
}
ConstantItemRibKind => {
// see #9186
self.resolve_error(span,
"cannot use an outer type \
parameter in this context");
}
}
}
Some(DlDef(def))
}
_ => Some(def_like)
}
}
/// Searches the current set of local scopes and
/// applies translations for closures.
fn search_ribs(&self,
ribs: &[Rib],
name: Name,
span: Span)
-> Option<DefLike> {
// FIXME #4950: Try caching?
for (i, rib) in ribs.iter().enumerate().rev() {
match rib.bindings.get(&name).cloned() {
Some(def_like) => {
return self.upvarify(&ribs[i + 1..], def_like, span);
}
None => {
// Continue.
}
}
}
None
}
/// Searches the current set of local scopes for labels.
/// Stops after meeting a closure.
fn search_label(&self, name: Name) -> Option<DefLike> {
for rib in self.label_ribs.iter().rev() {
match rib.kind {
NormalRibKind => {
// Continue
}
_ => {
// Do not resolve labels across function boundary
return None
}
}
let result = rib.bindings.get(&name).cloned();
if result.is_some() {
return result
}
}
None
}
fn resolve_crate(&mut self, krate: &ast::Crate) {
debug!("(resolving crate) starting");
visit::walk_crate(self, krate);
}
fn resolve_item(&mut self, item: &Item) {
let name = item.ident.name;
debug!("(resolving item) resolving {}",
token::get_name(name));
match item.node {
// enum item: resolve all the variants' discrs,
// then resolve the ty params
ItemEnum(ref enum_def, ref generics) => {
for variant in (*enum_def).variants.iter() {
for dis_expr in variant.node.disr_expr.iter() {
// resolve the discriminator expr
// as a constant
self.with_constant_rib(|this| {
this.resolve_expr(&**dis_expr);
});
}
}
// n.b. the discr expr gets visited twice.
// but maybe it's okay since the first time will signal an
// error if there is one? -- tjc
self.with_type_parameter_rib(HasTypeParameters(generics,
TypeSpace,
item.id,
ItemRibKind),
|this| {
this.resolve_type_parameters(&generics.ty_params);
this.resolve_where_clause(&generics.where_clause);
visit::walk_item(this, item);
});
}
ItemTy(_, ref generics) => {
self.with_type_parameter_rib(HasTypeParameters(generics,
TypeSpace,
item.id,
ItemRibKind),
|this| {
this.resolve_type_parameters(&generics.ty_params);
visit::walk_item(this, item);
});
}
ItemImpl(_, _,
ref generics,
ref implemented_traits,
ref self_type,
ref impl_items) => {
self.resolve_implementation(item.id,
generics,
implemented_traits,
&**self_type,
&impl_items[]);
}
ItemTrait(_, ref generics, ref bounds, ref trait_items) => {
// Create a new rib for the self type.
let mut self_type_rib = Rib::new(ItemRibKind);
// plain insert (no renaming, types are not currently hygienic....)
let name = self.type_self_name;
self_type_rib.bindings.insert(name, DlDef(DefSelfTy(item.id)));
self.type_ribs.push(self_type_rib);
// Create a new rib for the trait-wide type parameters.
self.with_type_parameter_rib(HasTypeParameters(generics,
TypeSpace,
item.id,
NormalRibKind),
|this| {
this.resolve_type_parameters(&generics.ty_params);
this.resolve_where_clause(&generics.where_clause);
this.resolve_type_parameter_bounds(item.id, bounds,
TraitDerivation);
for trait_item in (*trait_items).iter() {
// Create a new rib for the trait_item-specific type
// parameters.
//
// FIXME #4951: Do we need a node ID here?
match *trait_item {
ast::RequiredMethod(ref ty_m) => {
this.with_type_parameter_rib
(HasTypeParameters(&ty_m.generics,
FnSpace,
item.id,
MethodRibKind(item.id, RequiredMethod)),
|this| {
// Resolve the method-specific type
// parameters.
this.resolve_type_parameters(
&ty_m.generics.ty_params);
this.resolve_where_clause(&ty_m.generics
.where_clause);
for argument in ty_m.decl.inputs.iter() {
this.resolve_type(&*argument.ty);
}
if let SelfExplicit(ref typ, _) = ty_m.explicit_self.node {
this.resolve_type(&**typ)
}
if let ast::Return(ref ret_ty) = ty_m.decl.output {
this.resolve_type(&**ret_ty);
}
});
}
ast::ProvidedMethod(ref m) => {
this.resolve_method(MethodRibKind(item.id,
ProvidedMethod(m.id)),
&**m)
}
ast::TypeTraitItem(ref data) => {
this.resolve_type_parameter(&data.ty_param);
visit::walk_trait_item(this, trait_item);
}
}
}
});
self.type_ribs.pop();
}
ItemStruct(ref struct_def, ref generics) => {
self.resolve_struct(item.id,
generics,
&struct_def.fields[]);
}
ItemMod(ref module_) => {
self.with_scope(Some(name), |this| {
this.resolve_module(module_, item.span, name,
item.id);
});
}
ItemForeignMod(ref foreign_module) => {
self.with_scope(Some(name), |this| {
for foreign_item in foreign_module.items.iter() {
match foreign_item.node {
ForeignItemFn(_, ref generics) => {
this.with_type_parameter_rib(
HasTypeParameters(
generics, FnSpace, foreign_item.id,
ItemRibKind),
|this| {
this.resolve_type_parameters(&generics.ty_params);
this.resolve_where_clause(&generics.where_clause);
visit::walk_foreign_item(this, &**foreign_item)
});
}
ForeignItemStatic(..) => {
visit::walk_foreign_item(this,
&**foreign_item);
}
}
}
});
}
ItemFn(ref fn_decl, _, _, ref generics, ref block) => {
self.resolve_function(ItemRibKind,
Some(&**fn_decl),
HasTypeParameters
(generics,
FnSpace,
item.id,
ItemRibKind),
&**block);
}
ItemConst(..) | ItemStatic(..) => {
self.with_constant_rib(|this| {
visit::walk_item(this, item);
});
}
ItemExternCrate(_) | ItemUse(_) | ItemMac(..) => {
// do nothing, these are just around to be encoded
}
}
}
fn with_type_parameter_rib<F>(&mut self, type_parameters: TypeParameters, f: F) where
F: FnOnce(&mut Resolver),
{
match type_parameters {
HasTypeParameters(generics, space, node_id, rib_kind) => {
let mut function_type_rib = Rib::new(rib_kind);
let mut seen_bindings = HashSet::new();
for (index, type_parameter) in generics.ty_params.iter().enumerate() {
let name = type_parameter.ident.name;
debug!("with_type_parameter_rib: {} {}", node_id,
type_parameter.id);
if seen_bindings.contains(&name) {
self.resolve_error(type_parameter.span,
&format!("the name `{}` is already \
used for a type \
parameter in this type \
parameter list",
token::get_name(
name))[])
}
seen_bindings.insert(name);
let def_like = DlDef(DefTyParam(space,
index as u32,
local_def(type_parameter.id),
name));
// Associate this type parameter with
// the item that bound it
self.record_def(type_parameter.id,
(DefTyParamBinder(node_id), LastMod(AllPublic)));
// plain insert (no renaming)
function_type_rib.bindings.insert(name, def_like);
}
self.type_ribs.push(function_type_rib);
}
NoTypeParameters => {
// Nothing to do.
}
}
f(self);
match type_parameters {
HasTypeParameters(..) => { self.type_ribs.pop(); }
NoTypeParameters => { }
}
}
fn with_label_rib<F>(&mut self, f: F) where
F: FnOnce(&mut Resolver),
{
self.label_ribs.push(Rib::new(NormalRibKind));
f(self);
self.label_ribs.pop();
}
fn with_constant_rib<F>(&mut self, f: F) where
F: FnOnce(&mut Resolver),
{
self.value_ribs.push(Rib::new(ConstantItemRibKind));
self.type_ribs.push(Rib::new(ConstantItemRibKind));
f(self);
self.type_ribs.pop();
self.value_ribs.pop();
}
fn resolve_function(&mut self,
rib_kind: RibKind,
optional_declaration: Option<&FnDecl>,
type_parameters: TypeParameters,
block: &Block) {
// Create a value rib for the function.
let function_value_rib = Rib::new(rib_kind);
self.value_ribs.push(function_value_rib);
// Create a label rib for the function.
let function_label_rib = Rib::new(rib_kind);
self.label_ribs.push(function_label_rib);
// If this function has type parameters, add them now.
self.with_type_parameter_rib(type_parameters, |this| {
// Resolve the type parameters.
match type_parameters {
NoTypeParameters => {
// Continue.
}
HasTypeParameters(ref generics, _, _, _) => {
this.resolve_type_parameters(&generics.ty_params);
this.resolve_where_clause(&generics.where_clause);
}
}
// Add each argument to the rib.
match optional_declaration {
None => {
// Nothing to do.
}
Some(declaration) => {
let mut bindings_list = HashMap::new();
for argument in declaration.inputs.iter() {
this.resolve_pattern(&*argument.pat,
ArgumentIrrefutableMode,
&mut bindings_list);
this.resolve_type(&*argument.ty);
debug!("(resolving function) recorded argument");
}
if let ast::Return(ref ret_ty) = declaration.output {
this.resolve_type(&**ret_ty);
}
}
}
// Resolve the function body.
this.resolve_block(&*block);
debug!("(resolving function) leaving function");
});
self.label_ribs.pop();
self.value_ribs.pop();
}
fn resolve_type_parameters(&mut self,
type_parameters: &OwnedSlice<TyParam>) {
for type_parameter in type_parameters.iter() {
self.resolve_type_parameter(type_parameter);
}
}
fn resolve_type_parameter(&mut self,
type_parameter: &TyParam) {
for bound in type_parameter.bounds.iter() {
self.resolve_type_parameter_bound(type_parameter.id, bound,
TraitBoundingTypeParameter);
}
match type_parameter.default {
Some(ref ty) => self.resolve_type(&**ty),
None => {}
}
}
fn resolve_type_parameter_bounds(&mut self,
id: NodeId,
type_parameter_bounds: &OwnedSlice<TyParamBound>,
reference_type: TraitReferenceType) {
for type_parameter_bound in type_parameter_bounds.iter() {
self.resolve_type_parameter_bound(id, type_parameter_bound,
reference_type);
}
}
fn resolve_type_parameter_bound(&mut self,
id: NodeId,
type_parameter_bound: &TyParamBound,
reference_type: TraitReferenceType) {
match *type_parameter_bound {
TraitTyParamBound(ref tref, _) => {
self.resolve_poly_trait_reference(id, tref, reference_type)
}
RegionTyParamBound(..) => {}
}
}
fn resolve_poly_trait_reference(&mut self,
id: NodeId,
poly_trait_reference: &PolyTraitRef,
reference_type: TraitReferenceType) {
self.resolve_trait_reference(id, &poly_trait_reference.trait_ref, reference_type)
}
fn resolve_trait_reference(&mut self,
id: NodeId,
trait_reference: &TraitRef,
reference_type: TraitReferenceType) {
match self.resolve_path(id, &trait_reference.path, TypeNS, true) {
None => {
let path_str = self.path_names_to_string(&trait_reference.path);
let usage_str = match reference_type {
TraitBoundingTypeParameter => "bound type parameter with",
TraitImplementation => "implement",
TraitDerivation => "derive",
TraitObject => "reference",
TraitQPath => "extract an associated item from",
};
let msg = format!("attempt to {} a nonexistent trait `{}`", usage_str, path_str);
self.resolve_error(trait_reference.path.span, &msg[]);
}
Some(def) => {
match def {
(DefTrait(_), _) => {
debug!("(resolving trait) found trait def: {:?}", def);
self.record_def(trait_reference.ref_id, def);
}
(def, _) => {
self.resolve_error(trait_reference.path.span,
&format!("`{}` is not a trait",
self.path_names_to_string(
&trait_reference.path))[]);
// If it's a typedef, give a note
if let DefTy(..) = def {
self.session.span_note(
trait_reference.path.span,
&format!("`type` aliases cannot be used for traits")
[]);
}
}
}
}
}
}
fn resolve_where_clause(&mut self, where_clause: &ast::WhereClause) {
for predicate in where_clause.predicates.iter() {
match predicate {
&ast::WherePredicate::BoundPredicate(ref bound_pred) => {
self.resolve_type(&*bound_pred.bounded_ty);
for bound in bound_pred.bounds.iter() {
self.resolve_type_parameter_bound(bound_pred.bounded_ty.id, bound,
TraitBoundingTypeParameter);
}
}
&ast::WherePredicate::RegionPredicate(_) => {}
&ast::WherePredicate::EqPredicate(ref eq_pred) => {
match self.resolve_path(eq_pred.id, &eq_pred.path, TypeNS, true) {
Some((def @ DefTyParam(..), last_private)) => {
self.record_def(eq_pred.id, (def, last_private));
}
_ => {
self.resolve_error(eq_pred.path.span,
"undeclared associated type");
}
}
self.resolve_type(&*eq_pred.ty);
}
}
}
}
fn resolve_struct(&mut self,
id: NodeId,
generics: &Generics,
fields: &[StructField]) {
// If applicable, create a rib for the type parameters.
self.with_type_parameter_rib(HasTypeParameters(generics,
TypeSpace,
id,
ItemRibKind),
|this| {
// Resolve the type parameters.
this.resolve_type_parameters(&generics.ty_params);
this.resolve_where_clause(&generics.where_clause);
// Resolve fields.
for field in fields.iter() {
this.resolve_type(&*field.node.ty);
}
});
}
// Does this really need to take a RibKind or is it always going
// to be NormalRibKind?
fn resolve_method(&mut self,
rib_kind: RibKind,
method: &ast::Method) {
let method_generics = method.pe_generics();
let type_parameters = HasTypeParameters(method_generics,
FnSpace,
method.id,
rib_kind);
if let SelfExplicit(ref typ, _) = method.pe_explicit_self().node {
self.resolve_type(&**typ);
}
self.resolve_function(rib_kind,
Some(method.pe_fn_decl()),
type_parameters,
method.pe_body());
}
fn with_current_self_type<T, F>(&mut self, self_type: &Ty, f: F) -> T where
F: FnOnce(&mut Resolver) -> T,
{
// Handle nested impls (inside fn bodies)
let previous_value = replace(&mut self.current_self_type, Some(self_type.clone()));
let result = f(self);
self.current_self_type = previous_value;
result
}
fn with_optional_trait_ref<T, F>(&mut self, id: NodeId,
opt_trait_ref: &Option<TraitRef>,
f: F) -> T where
F: FnOnce(&mut Resolver) -> T,
{
let new_val = match *opt_trait_ref {
Some(ref trait_ref) => {
self.resolve_trait_reference(id, trait_ref, TraitImplementation);
match self.def_map.borrow().get(&trait_ref.ref_id) {
Some(def) => {
let did = def.def_id();
Some((did, trait_ref.clone()))
}
None => None
}
}
None => None
};
let original_trait_ref = replace(&mut self.current_trait_ref, new_val);
let result = f(self);
self.current_trait_ref = original_trait_ref;
result
}
fn resolve_implementation(&mut self,
id: NodeId,
generics: &Generics,
opt_trait_reference: &Option<TraitRef>,
self_type: &Ty,
impl_items: &[ImplItem]) {
// If applicable, create a rib for the type parameters.
self.with_type_parameter_rib(HasTypeParameters(generics,
TypeSpace,
id,
NormalRibKind),
|this| {
// Resolve the type parameters.
this.resolve_type_parameters(&generics.ty_params);
this.resolve_where_clause(&generics.where_clause);
// Resolve the trait reference, if necessary.
this.with_optional_trait_ref(id, opt_trait_reference, |this| {
// Resolve the self type.
this.resolve_type(self_type);
this.with_current_self_type(self_type, |this| {
for impl_item in impl_items.iter() {
match *impl_item {
MethodImplItem(ref method) => {
// If this is a trait impl, ensure the method
// exists in trait
this.check_trait_item(method.pe_ident().name,
method.span);
// We also need a new scope for the method-
// specific type parameters.
this.resolve_method(
MethodRibKind(id, ProvidedMethod(method.id)),
&**method);
}
TypeImplItem(ref typedef) => {
// If this is a trait impl, ensure the method
// exists in trait
this.check_trait_item(typedef.ident.name,
typedef.span);
this.resolve_type(&*typedef.typ);
}
}
}
});
});
});
// Check that the current type is indeed a type, if we have an anonymous impl
if opt_trait_reference.is_none() {
match self_type.node {
// TyPath is the only thing that we handled in `build_reduced_graph_for_item`,
// where we created a module with the name of the type in order to implement
// an anonymous trait. In the case that the path does not resolve to an actual
// type, the result will be that the type name resolves to a module but not
// a type (shadowing any imported modules or types with this name), leading
// to weird user-visible bugs. So we ward this off here. See #15060.
TyPath(ref path, path_id) => {
match self.def_map.borrow().get(&path_id) {
// FIXME: should we catch other options and give more precise errors?
Some(&DefMod(_)) => {
self.resolve_error(path.span, "inherent implementations are not \
allowed for types not defined in \
the current module");
}
_ => {}
}
}
_ => { }
}
}
}
fn check_trait_item(&self, name: Name, span: Span) {
// If there is a TraitRef in scope for an impl, then the method must be in the trait.
for &(did, ref trait_ref) in self.current_trait_ref.iter() {
if self.trait_item_map.get(&(name, did)).is_none() {
let path_str = self.path_names_to_string(&trait_ref.path);
self.resolve_error(span,
&format!("method `{}` is not a member of trait `{}`",
token::get_name(name),
path_str)[]);
}
}
}
fn resolve_module(&mut self, module: &Mod, _span: Span,
_name: Name, id: NodeId) {
// Write the implementations in scope into the module metadata.
debug!("(resolving module) resolving module ID {}", id);
visit::walk_mod(self, module);
}
fn resolve_local(&mut self, local: &Local) {
// Resolve the type.
if let Some(ref ty) = local.ty {
self.resolve_type(&**ty);
}
// Resolve the initializer, if necessary.
match local.init {
None => {
// Nothing to do.
}
Some(ref initializer) => {
self.resolve_expr(&**initializer);
}
}
// Resolve the pattern.
let mut bindings_list = HashMap::new();
self.resolve_pattern(&*local.pat,
LocalIrrefutableMode,
&mut bindings_list);
}
// build a map from pattern identifiers to binding-info's.
// this is done hygienically. This could arise for a macro
// that expands into an or-pattern where one 'x' was from the
// user and one 'x' came from the macro.
fn binding_mode_map(&mut self, pat: &Pat) -> BindingMap {
let mut result = HashMap::new();
pat_bindings(&self.def_map, pat, |binding_mode, _id, sp, path1| {
let name = mtwt::resolve(path1.node);
result.insert(name, BindingInfo {
span: sp,
binding_mode: binding_mode
});
});
return result;
}
// check that all of the arms in an or-pattern have exactly the
// same set of bindings, with the same binding modes for each.
fn check_consistent_bindings(&mut self, arm: &Arm) {
if arm.pats.len() == 0 {
return
}
let map_0 = self.binding_mode_map(&*arm.pats[0]);
for (i, p) in arm.pats.iter().enumerate() {
let map_i = self.binding_mode_map(&**p);
for (&key, &binding_0) in map_0.iter() {
match map_i.get(&key) {
None => {
self.resolve_error(
p.span,
&format!("variable `{}` from pattern #1 is \
not bound in pattern #{}",
token::get_name(key),
i + 1)[]);
}
Some(binding_i) => {
if binding_0.binding_mode != binding_i.binding_mode {
self.resolve_error(
binding_i.span,
&format!("variable `{}` is bound with different \
mode in pattern #{} than in pattern #1",
token::get_name(key),
i + 1)[]);
}
}
}
}
for (&key, &binding) in map_i.iter() {
if !map_0.contains_key(&key) {
self.resolve_error(
binding.span,
&format!("variable `{}` from pattern {}{} is \
not bound in pattern {}1",
token::get_name(key),
"#", i + 1, "#")[]);
}
}
}
}
fn resolve_arm(&mut self, arm: &Arm) {
self.value_ribs.push(Rib::new(NormalRibKind));
let mut bindings_list = HashMap::new();
for pattern in arm.pats.iter() {
self.resolve_pattern(&**pattern, RefutableMode, &mut bindings_list);
}
// This has to happen *after* we determine which
// pat_idents are variants
self.check_consistent_bindings(arm);
visit::walk_expr_opt(self, &arm.guard);
self.resolve_expr(&*arm.body);
self.value_ribs.pop();
}
fn resolve_block(&mut self, block: &Block) {
debug!("(resolving block) entering block");
self.value_ribs.push(Rib::new(NormalRibKind));
// Move down in the graph, if there's an anonymous module rooted here.
let orig_module = self.current_module.clone();
match orig_module.anonymous_children.borrow().get(&block.id) {
None => { /* Nothing to do. */ }
Some(anonymous_module) => {
debug!("(resolving block) found anonymous module, moving \
down");
self.current_module = anonymous_module.clone();
}
}
// Check for imports appearing after non-item statements.
let mut found_non_item = false;
for statement in block.stmts.iter() {
if let ast::StmtDecl(ref declaration, _) = statement.node {
if let ast::DeclItem(ref i) = declaration.node {
match i.node {
ItemExternCrate(_) | ItemUse(_) if found_non_item => {
span_err!(self.session, i.span, E0154,
"imports are not allowed after non-item statements");
}
_ => {}
}
} else {
found_non_item = true
}
} else {
found_non_item = true;
}
}
// Descend into the block.
visit::walk_block(self, block);
// Move back up.
self.current_module = orig_module;
self.value_ribs.pop();
debug!("(resolving block) leaving block");
}
fn resolve_type(&mut self, ty: &Ty) {
match ty.node {
// Like path expressions, the interpretation of path types depends
// on whether the path has multiple elements in it or not.
TyPath(ref path, path_id) => {
// This is a path in the type namespace. Walk through scopes
// looking for it.
let mut result_def = None;
// First, check to see whether the name is a primitive type.
if path.segments.len() == 1 {
let id = path.segments.last().unwrap().identifier;
match self.primitive_type_table
.primitive_types
.get(&id.name) {
Some(&primitive_type) => {
result_def =
Some((DefPrimTy(primitive_type), LastMod(AllPublic)));
if path.segments[0].parameters.has_lifetimes() {
span_err!(self.session, path.span, E0157,
"lifetime parameters are not allowed on this type");
} else if !path.segments[0].parameters.is_empty() {
span_err!(self.session, path.span, E0153,
"type parameters are not allowed on this type");
}
}
None => {
// Continue.
}
}
}
if let None = result_def {
result_def = self.resolve_path(ty.id, path, TypeNS, true);
}
match result_def {
Some(def) => {
// Write the result into the def map.
debug!("(resolving type) writing resolution for `{}` \
(id {}) = {:?}",
self.path_names_to_string(path),
path_id, def);
self.record_def(path_id, def);
}
None => {
let msg = format!("use of undeclared type name `{}`",
self.path_names_to_string(path));
self.resolve_error(ty.span, &msg[]);
}
}
}
TyObjectSum(ref ty, ref bound_vec) => {
self.resolve_type(&**ty);
self.resolve_type_parameter_bounds(ty.id, bound_vec,
TraitBoundingTypeParameter);
}
TyQPath(ref qpath) => {
self.resolve_type(&*qpath.self_type);
self.resolve_trait_reference(ty.id, &*qpath.trait_ref, TraitQPath);
for ty in qpath.item_path.parameters.types().into_iter() {
self.resolve_type(&**ty);
}
for binding in qpath.item_path.parameters.bindings().into_iter() {
self.resolve_type(&*binding.ty);
}
}
TyPolyTraitRef(ref bounds) => {
self.resolve_type_parameter_bounds(
ty.id,
bounds,
TraitObject);
visit::walk_ty(self, ty);
}
_ => {
// Just resolve embedded types.
visit::walk_ty(self, ty);
}
}
}
fn resolve_pattern(&mut self,
pattern: &Pat,
mode: PatternBindingMode,
// Maps idents to the node ID for the (outermost)
// pattern that binds them
bindings_list: &mut HashMap<Name, NodeId>) {
let pat_id = pattern.id;
walk_pat(pattern, |pattern| {
match pattern.node {
PatIdent(binding_mode, ref path1, _) => {
// The meaning of pat_ident with no type parameters
// depends on whether an enum variant or unit-like struct
// with that name is in scope. The probing lookup has to
// be careful not to emit spurious errors. Only matching
// patterns (match) can match nullary variants or
// unit-like structs. For binding patterns (let), matching
// such a value is simply disallowed (since it's rarely
// what you want).
let ident = path1.node;
let renamed = mtwt::resolve(ident);
match self.resolve_bare_identifier_pattern(ident.name, pattern.span) {
FoundStructOrEnumVariant(ref def, lp)
if mode == RefutableMode => {
debug!("(resolving pattern) resolving `{}` to \
struct or enum variant",
token::get_name(renamed));
self.enforce_default_binding_mode(
pattern,
binding_mode,
"an enum variant");
self.record_def(pattern.id, (def.clone(), lp));
}
FoundStructOrEnumVariant(..) => {
self.resolve_error(
pattern.span,
&format!("declaration of `{}` shadows an enum \
variant or unit-like struct in \
scope",
token::get_name(renamed))[]);
}
FoundConst(ref def, lp) if mode == RefutableMode => {
debug!("(resolving pattern) resolving `{}` to \
constant",
token::get_name(renamed));
self.enforce_default_binding_mode(
pattern,
binding_mode,
"a constant");
self.record_def(pattern.id, (def.clone(), lp));
}
FoundConst(..) => {
self.resolve_error(pattern.span,
"only irrefutable patterns \
allowed here");
}
BareIdentifierPatternUnresolved => {
debug!("(resolving pattern) binding `{}`",
token::get_name(renamed));
let def = DefLocal(pattern.id);
// Record the definition so that later passes
// will be able to distinguish variants from
// locals in patterns.
self.record_def(pattern.id, (def, LastMod(AllPublic)));
// Add the binding to the local ribs, if it
// doesn't already exist in the bindings list. (We
// must not add it if it's in the bindings list
// because that breaks the assumptions later
// passes make about or-patterns.)
if !bindings_list.contains_key(&renamed) {
let this = &mut *self;
let last_rib = this.value_ribs.last_mut().unwrap();
last_rib.bindings.insert(renamed, DlDef(def));
bindings_list.insert(renamed, pat_id);
} else if mode == ArgumentIrrefutableMode &&
bindings_list.contains_key(&renamed) {
// Forbid duplicate bindings in the same
// parameter list.
self.resolve_error(pattern.span,
&format!("identifier `{}` \
is bound more \
than once in \
this parameter \
list",
token::get_ident(
ident))
[])
} else if bindings_list.get(&renamed) ==
Some(&pat_id) {
// Then this is a duplicate variable in the
// same disjunction, which is an error.
self.resolve_error(pattern.span,
&format!("identifier `{}` is bound \
more than once in the same \
pattern",
token::get_ident(ident))[]);
}
// Else, not bound in the same pattern: do
// nothing.
}
}
}
PatEnum(ref path, _) => {
// This must be an enum variant, struct or const.
match self.resolve_path(pat_id, path, ValueNS, false) {
Some(def @ (DefVariant(..), _)) |
Some(def @ (DefStruct(..), _)) |
Some(def @ (DefConst(..), _)) => {
self.record_def(pattern.id, def);
}
Some((DefStatic(..), _)) => {
self.resolve_error(path.span,
"static variables cannot be \
referenced in a pattern, \
use a `const` instead");
}
Some(_) => {
self.resolve_error(path.span,
format!("`{}` is not an enum variant, struct or const",
token::get_ident(
path.segments.last().unwrap().identifier)).as_slice());
}
None => {
self.resolve_error(path.span,
format!("unresolved enum variant, struct or const `{}`",
token::get_ident(
path.segments.last().unwrap().identifier)).as_slice());
}
}
// Check the types in the path pattern.
for ty in path.segments
.iter()
.flat_map(|s| s.parameters.types().into_iter()) {
self.resolve_type(&**ty);
}
}
PatLit(ref expr) => {
self.resolve_expr(&**expr);
}
PatRange(ref first_expr, ref last_expr) => {
self.resolve_expr(&**first_expr);
self.resolve_expr(&**last_expr);
}
PatStruct(ref path, _, _) => {
match self.resolve_path(pat_id, path, TypeNS, false) {
Some(definition) => {
self.record_def(pattern.id, definition);
}
result => {
debug!("(resolving pattern) didn't find struct \
def: {:?}", result);
let msg = format!("`{}` does not name a structure",
self.path_names_to_string(path));
self.resolve_error(path.span, &msg[]);
}
}
}
_ => {
// Nothing to do.
}
}
true
});
}
fn resolve_bare_identifier_pattern(&mut self, name: Name, span: Span)
-> BareIdentifierPatternResolution {
let module = self.current_module.clone();
match self.resolve_item_in_lexical_scope(module,
name,
ValueNS) {
Success((target, _)) => {
debug!("(resolve bare identifier pattern) succeeded in \
finding {} at {:?}",
token::get_name(name),
target.bindings.value_def.borrow());
match *target.bindings.value_def.borrow() {
None => {
panic!("resolved name in the value namespace to a \
set of name bindings with no def?!");
}
Some(def) => {
// For the two success cases, this lookup can be
// considered as not having a private component because
// the lookup happened only within the current module.
match def.def {
def @ DefVariant(..) | def @ DefStruct(..) => {
return FoundStructOrEnumVariant(def, LastMod(AllPublic));
}
def @ DefConst(..) => {
return FoundConst(def, LastMod(AllPublic));
}
DefStatic(..) => {
self.resolve_error(span,
"static variables cannot be \
referenced in a pattern, \
use a `const` instead");
return BareIdentifierPatternUnresolved;
}
_ => {
return BareIdentifierPatternUnresolved;
}
}
}
}
}
Indeterminate => {
panic!("unexpected indeterminate result");
}
Failed(err) => {
match err {
Some((span, msg)) => {
self.resolve_error(span, &format!("failed to resolve: {}",
msg)[]);
}
None => ()
}
debug!("(resolve bare identifier pattern) failed to find {}",
token::get_name(name));
return BareIdentifierPatternUnresolved;
}
}
}
/// If `check_ribs` is true, checks the local definitions first; i.e.
/// doesn't skip straight to the containing module.
fn resolve_path(&mut self,
id: NodeId,
path: &Path,
namespace: Namespace,
check_ribs: bool) -> Option<(Def, LastPrivate)> {
// First, resolve the types and associated type bindings.
for ty in path.segments.iter().flat_map(|s| s.parameters.types().into_iter()) {
self.resolve_type(&**ty);
}
for binding in path.segments.iter().flat_map(|s| s.parameters.bindings().into_iter()) {
self.resolve_type(&*binding.ty);
}
// A special case for sugared associated type paths `T::A` where `T` is
// a type parameter and `A` is an associated type on some bound of `T`.
if namespace == TypeNS && path.segments.len() == 2 {
match self.resolve_identifier(path.segments[0].identifier,
TypeNS,
true,
path.span) {
Some((def, last_private)) => {
match def {
DefTyParam(_, _, did, _) => {
let def = DefAssociatedPath(TyParamProvenance::FromParam(did),
path.segments.last()
.unwrap().identifier);
return Some((def, last_private));
}
DefSelfTy(nid) => {
let def = DefAssociatedPath(TyParamProvenance::FromSelf(local_def(nid)),
path.segments.last()
.unwrap().identifier);
return Some((def, last_private));
}
_ => {}
}
}
_ => {}
}
}
if path.global {
return self.resolve_crate_relative_path(path, namespace);
}
// Try to find a path to an item in a module.
let unqualified_def =
self.resolve_identifier(path.segments.last().unwrap().identifier,
namespace,
check_ribs,
path.span);
if path.segments.len() > 1 {
let def = self.resolve_module_relative_path(path, namespace);
match (def, unqualified_def) {
(Some((ref d, _)), Some((ref ud, _))) if *d == *ud => {
self.session
.add_lint(lint::builtin::UNUSED_QUALIFICATIONS,
id,
path.span,
"unnecessary qualification".to_string());
}
_ => ()
}
return def;
}
return unqualified_def;
}
// resolve a single identifier (used as a varref)
fn resolve_identifier(&mut self,
identifier: Ident,
namespace: Namespace,
check_ribs: bool,
span: Span)
-> Option<(Def, LastPrivate)> {
if check_ribs {
match self.resolve_identifier_in_local_ribs(identifier,
namespace,
span) {
Some(def) => {
return Some((def, LastMod(AllPublic)));
}
None => {
// Continue.
}
}
}
return self.resolve_item_by_name_in_lexical_scope(identifier.name, namespace);
}
// FIXME #4952: Merge me with resolve_name_in_module?
fn resolve_definition_of_name_in_module(&mut self,
containing_module: Rc<Module>,
name: Name,
namespace: Namespace)
-> NameDefinition {
// First, search children.
build_reduced_graph::populate_module_if_necessary(self, &containing_module);
match containing_module.children.borrow().get(&name) {
Some(child_name_bindings) => {
match child_name_bindings.def_for_namespace(namespace) {
Some(def) => {
// Found it. Stop the search here.
let p = child_name_bindings.defined_in_public_namespace(
namespace);
let lp = if p {LastMod(AllPublic)} else {
LastMod(DependsOn(def.def_id()))
};
return ChildNameDefinition(def, lp);
}
None => {}
}
}
None => {}
}
// Next, search import resolutions.
match containing_module.import_resolutions.borrow().get(&name) {
Some(import_resolution) if import_resolution.is_public => {
if let Some(target) = (*import_resolution).target_for_namespace(namespace) {
match target.bindings.def_for_namespace(namespace) {
Some(def) => {
// Found it.
let id = import_resolution.id(namespace);
// track imports and extern crates as well
self.used_imports.insert((id, namespace));
self.record_import_use(id, name);
match target.target_module.def_id.get() {
Some(DefId{krate: kid, ..}) => {
self.used_crates.insert(kid);
},
_ => {}
}
return ImportNameDefinition(def, LastMod(AllPublic));
}
None => {
// This can happen with external impls, due to
// the imperfect way we read the metadata.
}
}
}
}
Some(..) | None => {} // Continue.
}
// Finally, search through external children.
if namespace == TypeNS {
if let Some(module) = containing_module.external_module_children.borrow()
.get(&name).cloned() {
if let Some(def_id) = module.def_id.get() {
// track used crates
self.used_crates.insert(def_id.krate);
let lp = if module.is_public {LastMod(AllPublic)} else {
LastMod(DependsOn(def_id))
};
return ChildNameDefinition(DefMod(def_id), lp);
}
}
}
return NoNameDefinition;
}
// resolve a "module-relative" path, e.g. a::b::c
fn resolve_module_relative_path(&mut self,
path: &Path,
namespace: Namespace)
-> Option<(Def, LastPrivate)> {
let module_path = path.segments.init().iter()
.map(|ps| ps.identifier.name)
.collect::<Vec<_>>();
let containing_module;
let last_private;
let module = self.current_module.clone();
match self.resolve_module_path(module,
&module_path[],
UseLexicalScope,
path.span,
PathSearch) {
Failed(err) => {
let (span, msg) = match err {
Some((span, msg)) => (span, msg),
None => {
let msg = format!("Use of undeclared type or module `{}`",
self.names_to_string(module_path.as_slice()));
(path.span, msg)
}
};
self.resolve_error(span, &format!("failed to resolve. {}",
msg)[]);
return None;
}
Indeterminate => panic!("indeterminate unexpected"),
Success((resulting_module, resulting_last_private)) => {
containing_module = resulting_module;
last_private = resulting_last_private;
}
}
let name = path.segments.last().unwrap().identifier.name;
let def = match self.resolve_definition_of_name_in_module(containing_module.clone(),
name,
namespace) {
NoNameDefinition => {
// We failed to resolve the name. Report an error.
return None;
}
ChildNameDefinition(def, lp) | ImportNameDefinition(def, lp) => {
(def, last_private.or(lp))
}
};
if let Some(DefId{krate: kid, ..}) = containing_module.def_id.get() {
self.used_crates.insert(kid);
}
return Some(def);
}
/// Invariant: This must be called only during main resolution, not during
/// import resolution.
fn resolve_crate_relative_path(&mut self,
path: &Path,
namespace: Namespace)
-> Option<(Def, LastPrivate)> {
let module_path = path.segments.init().iter()
.map(|ps| ps.identifier.name)
.collect::<Vec<_>>();
let root_module = self.graph_root.get_module();
let containing_module;
let last_private;
match self.resolve_module_path_from_root(root_module,
&module_path[],
0,
path.span,
PathSearch,
LastMod(AllPublic)) {
Failed(err) => {
let (span, msg) = match err {
Some((span, msg)) => (span, msg),
None => {
let msg = format!("Use of undeclared module `::{}`",
self.names_to_string(&module_path[]));
(path.span, msg)
}
};
self.resolve_error(span, &format!("failed to resolve. {}",
msg)[]);
return None;
}
Indeterminate => {
panic!("indeterminate unexpected");
}
Success((resulting_module, resulting_last_private)) => {
containing_module = resulting_module;
last_private = resulting_last_private;
}
}
let name = path.segments.last().unwrap().identifier.name;
match self.resolve_definition_of_name_in_module(containing_module,
name,
namespace) {
NoNameDefinition => {
// We failed to resolve the name. Report an error.
return None;
}
ChildNameDefinition(def, lp) | ImportNameDefinition(def, lp) => {
return Some((def, last_private.or(lp)));
}
}
}
fn resolve_identifier_in_local_ribs(&mut self,
ident: Ident,
namespace: Namespace,
span: Span)
-> Option<Def> {
// Check the local set of ribs.
let search_result = match namespace {
ValueNS => {
let renamed = mtwt::resolve(ident);
self.search_ribs(self.value_ribs.as_slice(), renamed, span)
}
TypeNS => {
let name = ident.name;
self.search_ribs(&self.type_ribs[], name, span)
}
};
match search_result {
Some(DlDef(def)) => {
debug!("(resolving path in local ribs) resolved `{}` to \
local: {:?}",
token::get_ident(ident),
def);
return Some(def);
}
Some(DlField) | Some(DlImpl(_)) | None => {
return None;
}
}
}
fn resolve_item_by_name_in_lexical_scope(&mut self,
name: Name,
namespace: Namespace)
-> Option<(Def, LastPrivate)> {
// Check the items.
let module = self.current_module.clone();
match self.resolve_item_in_lexical_scope(module,
name,
namespace) {
Success((target, _)) => {
match (*target.bindings).def_for_namespace(namespace) {
None => {
// This can happen if we were looking for a type and
// found a module instead. Modules don't have defs.
debug!("(resolving item path by identifier in lexical \
scope) failed to resolve {} after success...",
token::get_name(name));
return None;
}
Some(def) => {
debug!("(resolving item path in lexical scope) \
resolved `{}` to item",
token::get_name(name));
// This lookup is "all public" because it only searched
// for one identifier in the current module (couldn't
// have passed through reexports or anything like that.
return Some((def, LastMod(AllPublic)));
}
}
}
Indeterminate => {
panic!("unexpected indeterminate result");
}
Failed(err) => {
match err {
Some((span, msg)) =>
self.resolve_error(span, &format!("failed to resolve. {}",
msg)[]),
None => ()
}
debug!("(resolving item path by identifier in lexical scope) \
failed to resolve {}", token::get_name(name));
return None;
}
}
}
fn with_no_errors<T, F>(&mut self, f: F) -> T where
F: FnOnce(&mut Resolver) -> T,
{
self.emit_errors = false;
let rs = f(self);
self.emit_errors = true;
rs
}
fn resolve_error(&self, span: Span, s: &str) {
if self.emit_errors {
self.session.span_err(span, s);
}
}
fn find_fallback_in_self_type(&mut self, name: Name) -> FallbackSuggestion {
fn extract_path_and_node_id(t: &Ty, allow: FallbackChecks)
-> Option<(Path, NodeId, FallbackChecks)> {
match t.node {
TyPath(ref path, node_id) => Some((path.clone(), node_id, allow)),
TyPtr(ref mut_ty) => extract_path_and_node_id(&*mut_ty.ty, OnlyTraitAndStatics),
TyRptr(_, ref mut_ty) => extract_path_and_node_id(&*mut_ty.ty, allow),
// This doesn't handle the remaining `Ty` variants as they are not
// that commonly the self_type, it might be interesting to provide
// support for those in future.
_ => None,
}
}
fn get_module(this: &mut Resolver, span: Span, name_path: &[ast::Name])
-> Option<Rc<Module>> {
let root = this.current_module.clone();
let last_name = name_path.last().unwrap();
if name_path.len() == 1 {
match this.primitive_type_table.primitive_types.get(last_name) {
Some(_) => None,
None => {
match this.current_module.children.borrow().get(last_name) {
Some(child) => child.get_module_if_available(),
None => None
}
}
}
} else {
match this.resolve_module_path(root,
&name_path[],
UseLexicalScope,
span,
PathSearch) {
Success((module, _)) => Some(module),
_ => None
}
}
}
let (path, node_id, allowed) = match self.current_self_type {
Some(ref ty) => match extract_path_and_node_id(ty, Everything) {
Some(x) => x,
None => return NoSuggestion,
},
None => return NoSuggestion,
};
if allowed == Everything {
// Look for a field with the same name in the current self_type.
match self.def_map.borrow().get(&node_id) {
Some(&DefTy(did, _))
| Some(&DefStruct(did))
| Some(&DefVariant(_, did, _)) => match self.structs.get(&did) {
None => {}
Some(fields) => {
if fields.iter().any(|&field_name| name == field_name) {
return Field;
}
}
},
_ => {} // Self type didn't resolve properly
}
}
let name_path = path.segments.iter().map(|seg| seg.identifier.name).collect::<Vec<_>>();
// Look for a method in the current self type's impl module.
match get_module(self, path.span, &name_path[]) {
Some(module) => match module.children.borrow().get(&name) {
Some(binding) => {
let p_str = self.path_names_to_string(&path);
match binding.def_for_namespace(ValueNS) {
Some(DefStaticMethod(_, provenance)) => {
match provenance {
FromImpl(_) => return StaticMethod(p_str),
FromTrait(_) => unreachable!()
}
}
Some(DefMethod(_, None, _)) if allowed == Everything => return Method,
Some(DefMethod(_, Some(_), _)) => return TraitItem,
_ => ()
}
}
None => {}
},
None => {}
}
// Look for a method in the current trait.
match self.current_trait_ref {
Some((did, ref trait_ref)) => {
let path_str = self.path_names_to_string(&trait_ref.path);
match self.trait_item_map.get(&(name, did)) {
Some(&StaticMethodTraitItemKind) => {
return TraitMethod(path_str)
}
Some(_) => return TraitItem,
None => {}
}
}
None => {}
}
NoSuggestion
}
fn find_best_match_for_name(&mut self, name: &str, max_distance: uint)
-> Option<String> {
let this = &mut *self;
let mut maybes: Vec<token::InternedString> = Vec::new();
let mut values: Vec<uint> = Vec::new();
for rib in this.value_ribs.iter().rev() {
for (&k, _) in rib.bindings.iter() {
maybes.push(token::get_name(k));
values.push(uint::MAX);
}
}
let mut smallest = 0;
for (i, other) in maybes.iter().enumerate() {
values[i] = lev_distance(name, other.get());
if values[i] <= values[smallest] {
smallest = i;
}
}
if values.len() > 0 &&
values[smallest] != uint::MAX &&
values[smallest] < name.len() + 2 &&
values[smallest] <= max_distance &&
name != maybes[smallest].get() {
Some(maybes[smallest].get().to_string())
} else {
None
}
}
fn resolve_expr(&mut self, expr: &Expr) {
// First, record candidate traits for this expression if it could
// result in the invocation of a method call.
self.record_candidate_traits_for_expr_if_necessary(expr);
// Next, resolve the node.
match expr.node {
// The interpretation of paths depends on whether the path has
// multiple elements in it or not.
ExprPath(_) | ExprQPath(_) => {
let mut path_from_qpath;
let path = match expr.node {
ExprPath(ref path) => path,
ExprQPath(ref qpath) => {
self.resolve_type(&*qpath.self_type);
self.resolve_trait_reference(expr.id, &*qpath.trait_ref, TraitQPath);
path_from_qpath = qpath.trait_ref.path.clone();
path_from_qpath.segments.push(qpath.item_path.clone());
&path_from_qpath
}
_ => unreachable!()
};
// This is a local path in the value namespace. Walk through
// scopes looking for it.
match self.resolve_path(expr.id, path, ValueNS, true) {
// Check if struct variant
Some((DefVariant(_, _, true), _)) => {
let path_name = self.path_names_to_string(path);
self.resolve_error(expr.span,
format!("`{}` is a struct variant name, but \
this expression \
uses it like a function name",
path_name).as_slice());
self.session.span_help(expr.span,
format!("Did you mean to write: \
`{} {{ /* fields */ }}`?",
path_name).as_slice());
}
Some(def) => {
// Write the result into the def map.
debug!("(resolving expr) resolved `{}`",
self.path_names_to_string(path));
self.record_def(expr.id, def);
}
None => {
// Be helpful if the name refers to a struct
// (The pattern matching def_tys where the id is in self.structs
// matches on regular structs while excluding tuple- and enum-like
// structs, which wouldn't result in this error.)
let path_name = self.path_names_to_string(path);
match self.with_no_errors(|this|
this.resolve_path(expr.id, path, TypeNS, false)) {
Some((DefTy(struct_id, _), _))
if self.structs.contains_key(&struct_id) => {
self.resolve_error(expr.span,
format!("`{}` is a structure name, but \
this expression \
uses it like a function name",
path_name).as_slice());
self.session.span_help(expr.span,
format!("Did you mean to write: \
`{} {{ /* fields */ }}`?",
path_name).as_slice());
}
_ => {
let mut method_scope = false;
self.value_ribs.iter().rev().all(|rib| {
let res = match *rib {
Rib { bindings: _, kind: MethodRibKind(_, _) } => true,
Rib { bindings: _, kind: ItemRibKind } => false,
_ => return true, // Keep advancing
};
method_scope = res;
false // Stop advancing
});
if method_scope && token::get_name(self.self_name).get()
== path_name {
self.resolve_error(
expr.span,
"`self` is not available \
in a static method. Maybe a \
`self` argument is missing?");
} else {
let last_name = path.segments.last().unwrap().identifier.name;
let mut msg = match self.find_fallback_in_self_type(last_name) {
NoSuggestion => {
// limit search to 5 to reduce the number
// of stupid suggestions
self.find_best_match_for_name(path_name.as_slice(), 5)
.map_or("".to_string(),
|x| format!("`{}`", x))
}
Field =>
format!("`self.{}`", path_name),
Method
| TraitItem =>
format!("to call `self.{}`", path_name),
TraitMethod(path_str)
| StaticMethod(path_str) =>
format!("to call `{}::{}`", path_str, path_name)
};
if msg.len() > 0 {
msg = format!(". Did you mean {}?", msg)
}
self.resolve_error(
expr.span,
format!("unresolved name `{}`{}",
path_name,
msg).as_slice());
}
}
}
}
}
visit::walk_expr(self, expr);
}
ExprClosure(_, _, ref fn_decl, ref block) => {
self.resolve_function(ClosureRibKind(expr.id),
Some(&**fn_decl), NoTypeParameters,
&**block);
}
ExprStruct(ref path, _, _) => {
// Resolve the path to the structure it goes to. We don't
// check to ensure that the path is actually a structure; that
// is checked later during typeck.
match self.resolve_path(expr.id, path, TypeNS, false) {
Some(definition) => self.record_def(expr.id, definition),
result => {
debug!("(resolving expression) didn't find struct \
def: {:?}", result);
let msg = format!("`{}` does not name a structure",
self.path_names_to_string(path));
self.resolve_error(path.span, &msg[]);
}
}
visit::walk_expr(self, expr);
}
ExprLoop(_, Some(label)) | ExprWhile(_, _, Some(label)) => {
self.with_label_rib(|this| {
let def_like = DlDef(DefLabel(expr.id));
{
let rib = this.label_ribs.last_mut().unwrap();
let renamed = mtwt::resolve(label);
rib.bindings.insert(renamed, def_like);
}
visit::walk_expr(this, expr);
})
}
ExprBreak(Some(label)) | ExprAgain(Some(label)) => {
let renamed = mtwt::resolve(label);
match self.search_label(renamed) {
None => {
self.resolve_error(
expr.span,
&format!("use of undeclared label `{}`",
token::get_ident(label))[])
}
Some(DlDef(def @ DefLabel(_))) => {
// Since this def is a label, it is never read.
self.record_def(expr.id, (def, LastMod(AllPublic)))
}
Some(_) => {
self.session.span_bug(expr.span,
"label wasn't mapped to a \
label def!")
}
}
}
_ => {
visit::walk_expr(self, expr);
}
}
}
fn record_candidate_traits_for_expr_if_necessary(&mut self, expr: &Expr) {
match expr.node {
ExprField(_, ident) => {
// FIXME(#6890): Even though you can't treat a method like a
// field, we need to add any trait methods we find that match
// the field name so that we can do some nice error reporting
// later on in typeck.
let traits = self.search_for_traits_containing_method(ident.node.name);
self.trait_map.insert(expr.id, traits);
}
ExprMethodCall(ident, _, _) => {
debug!("(recording candidate traits for expr) recording \
traits for {}",
expr.id);
let traits = self.search_for_traits_containing_method(ident.node.name);
self.trait_map.insert(expr.id, traits);
}
_ => {
// Nothing to do.
}
}
}
fn search_for_traits_containing_method(&mut self, name: Name) -> Vec<DefId> {
debug!("(searching for traits containing method) looking for '{}'",
token::get_name(name));
fn add_trait_info(found_traits: &mut Vec<DefId>,
trait_def_id: DefId,
name: Name) {
debug!("(adding trait info) found trait {}:{} for method '{}'",
trait_def_id.krate,
trait_def_id.node,
token::get_name(name));
found_traits.push(trait_def_id);
}
let mut found_traits = Vec::new();
let mut search_module = self.current_module.clone();
loop {
// Look for the current trait.
match self.current_trait_ref {
Some((trait_def_id, _)) => {
if self.trait_item_map.contains_key(&(name, trait_def_id)) {
add_trait_info(&mut found_traits, trait_def_id, name);
}
}
None => {} // Nothing to do.
}
// Look for trait children.
build_reduced_graph::populate_module_if_necessary(self, &search_module);
{
for (_, child_names) in search_module.children.borrow().iter() {
let def = match child_names.def_for_namespace(TypeNS) {
Some(def) => def,
None => continue
};
let trait_def_id = match def {
DefTrait(trait_def_id) => trait_def_id,
_ => continue,
};
if self.trait_item_map.contains_key(&(name, trait_def_id)) {
add_trait_info(&mut found_traits, trait_def_id, name);
}
}
}
// Look for imports.
for (_, import) in search_module.import_resolutions.borrow().iter() {
let target = match import.target_for_namespace(TypeNS) {
None => continue,
Some(target) => target,
};
let did = match target.bindings.def_for_namespace(TypeNS) {
Some(DefTrait(trait_def_id)) => trait_def_id,
Some(..) | None => continue,
};
if self.trait_item_map.contains_key(&(name, did)) {
add_trait_info(&mut found_traits, did, name);
let id = import.type_id;
self.used_imports.insert((id, TypeNS));
let trait_name = self.get_trait_name(did);
self.record_import_use(id, trait_name);
if let Some(DefId{krate: kid, ..}) = target.target_module.def_id.get() {
self.used_crates.insert(kid);
}
}
}
match search_module.parent_link.clone() {
NoParentLink | ModuleParentLink(..) => break,
BlockParentLink(parent_module, _) => {
search_module = parent_module.upgrade().unwrap();
}
}
}
found_traits
}
fn record_def(&mut self, node_id: NodeId, (def, lp): (Def, LastPrivate)) {
debug!("(recording def) recording {:?} for {}, last private {:?}",
def, node_id, lp);
assert!(match lp {LastImport{..} => false, _ => true},
"Import should only be used for `use` directives");
self.last_private.insert(node_id, lp);
match self.def_map.borrow_mut().entry(node_id) {
// Resolve appears to "resolve" the same ID multiple
// times, so here is a sanity check it at least comes to
// the same conclusion! - nmatsakis
Occupied(entry) => if def != *entry.get() {
self.session
.bug(&format!("node_id {} resolved first to {:?} and \
then {:?}",
node_id,
*entry.get(),
def)[]);
},
Vacant(entry) => { entry.insert(def); },
}
}
fn enforce_default_binding_mode(&mut self,
pat: &Pat,
pat_binding_mode: BindingMode,
descr: &str) {
match pat_binding_mode {
BindByValue(_) => {}
BindByRef(..) => {
self.resolve_error(pat.span,
&format!("cannot use `ref` binding mode \
with {}",
descr)[]);
}
}
}
//
// Diagnostics
//
// Diagnostics are not particularly efficient, because they're rarely
// hit.
//
/// A somewhat inefficient routine to obtain the name of a module.
fn module_to_string(&self, module: &Module) -> String {
let mut names = Vec::new();
fn collect_mod(names: &mut Vec<ast::Name>, module: &Module) {
match module.parent_link {
NoParentLink => {}
ModuleParentLink(ref module, name) => {
names.push(name);
collect_mod(names, &*module.upgrade().unwrap());
}
BlockParentLink(ref module, _) => {
// danger, shouldn't be ident?
names.push(special_idents::opaque.name);
collect_mod(names, &*module.upgrade().unwrap());
}
}
}
collect_mod(&mut names, module);
if names.len() == 0 {
return "???".to_string();
}
self.names_to_string(&names.into_iter().rev()
.collect::<Vec<ast::Name>>()[])
}
#[allow(dead_code)] // useful for debugging
fn dump_module(&mut self, module_: Rc<Module>) {
debug!("Dump of module `{}`:", self.module_to_string(&*module_));
debug!("Children:");
build_reduced_graph::populate_module_if_necessary(self, &module_);
for (&name, _) in module_.children.borrow().iter() {
debug!("* {}", token::get_name(name));
}
debug!("Import resolutions:");
let import_resolutions = module_.import_resolutions.borrow();
for (&name, import_resolution) in import_resolutions.iter() {
let value_repr;
match import_resolution.target_for_namespace(ValueNS) {
None => { value_repr = "".to_string(); }
Some(_) => {
value_repr = " value:?".to_string();
// FIXME #4954
}
}
let type_repr;
match import_resolution.target_for_namespace(TypeNS) {
None => { type_repr = "".to_string(); }
Some(_) => {
type_repr = " type:?".to_string();
// FIXME #4954
}
}
debug!("* {}:{}{}", token::get_name(name), value_repr, type_repr);
}
}
}
pub struct CrateMap {
pub def_map: DefMap,
pub freevars: RefCell<FreevarMap>,
pub export_map: ExportMap,
pub trait_map: TraitMap,
pub external_exports: ExternalExports,
pub last_private_map: LastPrivateMap,
pub glob_map: Option<GlobMap>
}
#[derive(PartialEq,Copy)]
pub enum MakeGlobMap {
Yes,
No
}
/// Entry point to crate resolution.
pub fn resolve_crate<'a, 'tcx>(session: &'a Session,
ast_map: &'a ast_map::Map<'tcx>,
_: &LanguageItems,
krate: &Crate,
make_glob_map: MakeGlobMap)
-> CrateMap {
let mut resolver = Resolver::new(session, ast_map, krate.span, make_glob_map);
build_reduced_graph::build_reduced_graph(&mut resolver, krate);
session.abort_if_errors();
resolver.resolve_imports();
session.abort_if_errors();
record_exports::record(&mut resolver);
session.abort_if_errors();
resolver.resolve_crate(krate);
session.abort_if_errors();
check_unused::check_crate(&mut resolver, krate);
CrateMap {
def_map: resolver.def_map,
freevars: resolver.freevars,
export_map: resolver.export_map,
trait_map: resolver.trait_map,
external_exports: resolver.external_exports,
last_private_map: resolver.last_private,
glob_map: if resolver.make_glob_map {
Some(resolver.glob_map)
} else {
None
},
}
}