929 lines
40 KiB
Rust
929 lines
40 KiB
Rust
// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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use self::ImportDirectiveSubclass::*;
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use {AmbiguityError, Module, PerNS};
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use Namespace::{self, TypeNS, MacroNS};
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use {NameBinding, NameBindingKind, PathResult, PrivacyError};
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use Resolver;
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use {names_to_string, module_to_string};
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use {resolve_error, ResolutionError};
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use rustc::ty;
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use rustc::lint::builtin::PUB_USE_OF_PRIVATE_EXTERN_CRATE;
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use rustc::hir::def_id::DefId;
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use rustc::hir::def::*;
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use rustc::util::nodemap::{FxHashMap, FxHashSet};
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use syntax::ast::{Ident, SpannedIdent, NodeId};
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use syntax::ext::base::Determinacy::{self, Determined, Undetermined};
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use syntax::ext::hygiene::Mark;
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use syntax::parse::token;
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use syntax::symbol::keywords;
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use syntax::util::lev_distance::find_best_match_for_name;
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use syntax_pos::Span;
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use std::cell::{Cell, RefCell};
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use std::mem;
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/// Contains data for specific types of import directives.
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#[derive(Clone, Debug)]
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pub enum ImportDirectiveSubclass<'a> {
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SingleImport {
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target: Ident,
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source: Ident,
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result: PerNS<Cell<Result<&'a NameBinding<'a>, Determinacy>>>,
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type_ns_only: bool,
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},
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GlobImport {
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is_prelude: bool,
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max_vis: Cell<ty::Visibility>, // The visibility of the greatest reexport.
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// n.b. `max_vis` is only used in `finalize_import` to check for reexport errors.
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},
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ExternCrate,
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MacroUse,
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}
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/// One import directive.
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#[derive(Debug,Clone)]
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pub struct ImportDirective<'a> {
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pub id: NodeId,
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pub parent: Module<'a>,
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pub module_path: Vec<SpannedIdent>,
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pub imported_module: Cell<Option<Module<'a>>>, // the resolution of `module_path`
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pub subclass: ImportDirectiveSubclass<'a>,
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pub span: Span,
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pub vis: Cell<ty::Visibility>,
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pub expansion: Mark,
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pub used: Cell<bool>,
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}
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impl<'a> ImportDirective<'a> {
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pub fn is_glob(&self) -> bool {
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match self.subclass { ImportDirectiveSubclass::GlobImport { .. } => true, _ => false }
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}
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}
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#[derive(Clone, Default)]
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/// Records information about the resolution of a name in a namespace of a module.
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pub struct NameResolution<'a> {
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/// The single imports that define the name in the namespace.
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single_imports: SingleImports<'a>,
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/// The least shadowable known binding for this name, or None if there are no known bindings.
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pub binding: Option<&'a NameBinding<'a>>,
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shadows_glob: Option<&'a NameBinding<'a>>,
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}
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#[derive(Clone, Debug)]
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enum SingleImports<'a> {
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/// No single imports can define the name in the namespace.
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None,
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/// Only the given single import can define the name in the namespace.
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MaybeOne(&'a ImportDirective<'a>),
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/// At least one single import will define the name in the namespace.
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AtLeastOne,
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}
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impl<'a> Default for SingleImports<'a> {
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/// Creates a `SingleImports<'a>` of None type.
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fn default() -> Self {
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SingleImports::None
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}
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}
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impl<'a> SingleImports<'a> {
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fn add_directive(&mut self, directive: &'a ImportDirective<'a>) {
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match *self {
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SingleImports::None => *self = SingleImports::MaybeOne(directive),
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// If two single imports can define the name in the namespace, we can assume that at
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// least one of them will define it since otherwise both would have to define only one
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// namespace, leading to a duplicate error.
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SingleImports::MaybeOne(_) => *self = SingleImports::AtLeastOne,
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SingleImports::AtLeastOne => {}
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};
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}
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fn directive_failed(&mut self) {
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match *self {
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SingleImports::None => unreachable!(),
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SingleImports::MaybeOne(_) => *self = SingleImports::None,
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SingleImports::AtLeastOne => {}
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}
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}
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}
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impl<'a> NameResolution<'a> {
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// Returns the binding for the name if it is known or None if it not known.
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fn binding(&self) -> Option<&'a NameBinding<'a>> {
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self.binding.and_then(|binding| match self.single_imports {
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SingleImports::None => Some(binding),
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_ if !binding.is_glob_import() => Some(binding),
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_ => None, // The binding could be shadowed by a single import, so it is not known.
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})
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}
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}
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impl<'a> Resolver<'a> {
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fn resolution(&self, module: Module<'a>, ident: Ident, ns: Namespace)
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-> &'a RefCell<NameResolution<'a>> {
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*module.resolutions.borrow_mut().entry((ident.modern(), ns))
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.or_insert_with(|| self.arenas.alloc_name_resolution())
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}
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/// Attempts to resolve `ident` in namespaces `ns` of `module`.
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/// Invariant: if `record_used` is `Some`, import resolution must be complete.
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pub fn resolve_ident_in_module_unadjusted(&mut self,
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module: Module<'a>,
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ident: Ident,
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ns: Namespace,
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restricted_shadowing: bool,
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record_used: bool,
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path_span: Span)
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-> Result<&'a NameBinding<'a>, Determinacy> {
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self.populate_module_if_necessary(module);
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let resolution = self.resolution(module, ident, ns)
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.try_borrow_mut()
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.map_err(|_| Determined)?; // This happens when there is a cycle of imports
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if record_used {
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if let Some(binding) = resolution.binding {
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if let Some(shadowed_glob) = resolution.shadows_glob {
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let name = ident.name;
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// Forbid expanded shadowing to avoid time travel.
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if restricted_shadowing &&
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binding.expansion != Mark::root() &&
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ns != MacroNS && // In MacroNS, `try_define` always forbids this shadowing
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binding.def() != shadowed_glob.def() {
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self.ambiguity_errors.push(AmbiguityError {
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span: path_span,
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name: name,
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lexical: false,
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b1: binding,
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b2: shadowed_glob,
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legacy: false,
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});
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}
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}
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if self.record_use(ident, ns, binding, path_span) {
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return Ok(self.dummy_binding);
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}
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if !self.is_accessible(binding.vis) {
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self.privacy_errors.push(PrivacyError(path_span, ident.name, binding));
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}
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}
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return resolution.binding.ok_or(Determined);
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}
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let check_usable = |this: &mut Self, binding: &'a NameBinding<'a>| {
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// `extern crate` are always usable for backwards compatability, see issue #37020.
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let usable = this.is_accessible(binding.vis) || binding.is_extern_crate();
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if usable { Ok(binding) } else { Err(Determined) }
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};
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// Items and single imports are not shadowable.
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if let Some(binding) = resolution.binding {
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if !binding.is_glob_import() {
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return check_usable(self, binding);
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}
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}
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// Check if a single import can still define the name.
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match resolution.single_imports {
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SingleImports::AtLeastOne => return Err(Undetermined),
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SingleImports::MaybeOne(directive) if self.is_accessible(directive.vis.get()) => {
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let module = match directive.imported_module.get() {
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Some(module) => module,
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None => return Err(Undetermined),
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};
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let ident = match directive.subclass {
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SingleImport { source, .. } => source,
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_ => unreachable!(),
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};
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match self.resolve_ident_in_module(module, ident, ns, false, false, path_span) {
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Err(Determined) => {}
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_ => return Err(Undetermined),
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}
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}
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SingleImports::MaybeOne(_) | SingleImports::None => {},
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}
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let no_unresolved_invocations =
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restricted_shadowing || module.unresolved_invocations.borrow().is_empty();
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match resolution.binding {
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// In `MacroNS`, expanded bindings do not shadow (enforced in `try_define`).
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Some(binding) if no_unresolved_invocations || ns == MacroNS =>
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return check_usable(self, binding),
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None if no_unresolved_invocations => {}
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_ => return Err(Undetermined),
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}
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// Check if the globs are determined
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if restricted_shadowing && module.def().is_some() {
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return Err(Determined);
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}
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for directive in module.globs.borrow().iter() {
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if !self.is_accessible(directive.vis.get()) {
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continue
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}
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let module = unwrap_or!(directive.imported_module.get(), return Err(Undetermined));
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let (orig_current_module, mut ident) = (self.current_module, ident.modern());
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match ident.ctxt.glob_adjust(module.expansion, directive.span.ctxt.modern()) {
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Some(Some(def)) => self.current_module = self.macro_def_scope(def),
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Some(None) => {}
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None => continue,
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};
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let result = self.resolve_ident_in_module_unadjusted(
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module, ident, ns, false, false, path_span,
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);
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self.current_module = orig_current_module;
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if let Err(Undetermined) = result {
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return Err(Undetermined);
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}
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}
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Err(Determined)
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}
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// Add an import directive to the current module.
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pub fn add_import_directive(&mut self,
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module_path: Vec<SpannedIdent>,
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subclass: ImportDirectiveSubclass<'a>,
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span: Span,
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id: NodeId,
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vis: ty::Visibility,
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expansion: Mark) {
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let current_module = self.current_module;
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let directive = self.arenas.alloc_import_directive(ImportDirective {
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parent: current_module,
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module_path: module_path,
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imported_module: Cell::new(None),
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subclass: subclass,
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span: span,
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id: id,
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vis: Cell::new(vis),
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expansion: expansion,
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used: Cell::new(false),
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});
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self.indeterminate_imports.push(directive);
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match directive.subclass {
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SingleImport { target, .. } => {
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self.per_ns(|this, ns| {
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let mut resolution = this.resolution(current_module, target, ns).borrow_mut();
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resolution.single_imports.add_directive(directive);
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});
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}
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// We don't add prelude imports to the globs since they only affect lexical scopes,
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// which are not relevant to import resolution.
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GlobImport { is_prelude: true, .. } => {}
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GlobImport { .. } => self.current_module.globs.borrow_mut().push(directive),
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_ => unreachable!(),
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}
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}
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// Given a binding and an import directive that resolves to it,
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// return the corresponding binding defined by the import directive.
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pub fn import(&self, binding: &'a NameBinding<'a>, directive: &'a ImportDirective<'a>)
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-> &'a NameBinding<'a> {
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let vis = if binding.pseudo_vis().is_at_least(directive.vis.get(), self) ||
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// c.f. `PUB_USE_OF_PRIVATE_EXTERN_CRATE`
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!directive.is_glob() && binding.is_extern_crate() {
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directive.vis.get()
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} else {
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binding.pseudo_vis()
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};
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if let GlobImport { ref max_vis, .. } = directive.subclass {
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if vis == directive.vis.get() || vis.is_at_least(max_vis.get(), self) {
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max_vis.set(vis)
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}
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}
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self.arenas.alloc_name_binding(NameBinding {
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kind: NameBindingKind::Import {
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binding: binding,
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directive: directive,
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used: Cell::new(false),
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legacy_self_import: false,
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},
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span: directive.span,
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vis: vis,
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expansion: directive.expansion,
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})
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}
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// Define the name or return the existing binding if there is a collision.
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pub fn try_define(&mut self,
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module: Module<'a>,
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ident: Ident,
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ns: Namespace,
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binding: &'a NameBinding<'a>)
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-> Result<(), &'a NameBinding<'a>> {
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self.update_resolution(module, ident, ns, |this, resolution| {
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if let Some(old_binding) = resolution.binding {
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if binding.is_glob_import() {
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if !old_binding.is_glob_import() &&
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!(ns == MacroNS && old_binding.expansion != Mark::root()) {
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resolution.shadows_glob = Some(binding);
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} else if binding.def() != old_binding.def() {
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resolution.binding = Some(this.ambiguity(old_binding, binding));
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} else if !old_binding.vis.is_at_least(binding.vis, &*this) {
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// We are glob-importing the same item but with greater visibility.
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resolution.binding = Some(binding);
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}
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} else if old_binding.is_glob_import() {
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if ns == MacroNS && binding.expansion != Mark::root() &&
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binding.def() != old_binding.def() {
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resolution.binding = Some(this.ambiguity(binding, old_binding));
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} else {
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resolution.binding = Some(binding);
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resolution.shadows_glob = Some(old_binding);
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}
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} else {
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return Err(old_binding);
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}
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} else {
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resolution.binding = Some(binding);
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}
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Ok(())
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})
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}
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pub fn ambiguity(&self, b1: &'a NameBinding<'a>, b2: &'a NameBinding<'a>)
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-> &'a NameBinding<'a> {
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self.arenas.alloc_name_binding(NameBinding {
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kind: NameBindingKind::Ambiguity { b1: b1, b2: b2, legacy: false },
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vis: if b1.vis.is_at_least(b2.vis, self) { b1.vis } else { b2.vis },
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span: b1.span,
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expansion: Mark::root(),
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})
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}
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// Use `f` to mutate the resolution of the name in the module.
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// If the resolution becomes a success, define it in the module's glob importers.
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fn update_resolution<T, F>(&mut self, module: Module<'a>, ident: Ident, ns: Namespace, f: F)
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-> T
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where F: FnOnce(&mut Resolver<'a>, &mut NameResolution<'a>) -> T
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{
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// Ensure that `resolution` isn't borrowed when defining in the module's glob importers,
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// during which the resolution might end up getting re-defined via a glob cycle.
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let (binding, t) = {
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let resolution = &mut *self.resolution(module, ident, ns).borrow_mut();
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let old_binding = resolution.binding();
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let t = f(self, resolution);
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match resolution.binding() {
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_ if old_binding.is_some() => return t,
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None => return t,
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Some(binding) => match old_binding {
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Some(old_binding) if old_binding as *const _ == binding as *const _ => return t,
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_ => (binding, t),
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}
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}
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};
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// Define `binding` in `module`s glob importers.
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for directive in module.glob_importers.borrow_mut().iter() {
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let mut ident = ident.modern();
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let scope = match ident.ctxt.reverse_glob_adjust(module.expansion,
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directive.span.ctxt.modern()) {
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Some(Some(def)) => self.macro_def_scope(def),
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Some(None) => directive.parent,
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None => continue,
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};
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if self.is_accessible_from(binding.vis, scope) {
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let imported_binding = self.import(binding, directive);
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let _ = self.try_define(directive.parent, ident, ns, imported_binding);
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}
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}
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t
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}
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|
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// Define a "dummy" resolution containing a Def::Err as a placeholder for a
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// failed resolution
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fn import_dummy_binding(&mut self, directive: &'a ImportDirective<'a>) {
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if let SingleImport { target, .. } = directive.subclass {
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let dummy_binding = self.dummy_binding;
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let dummy_binding = self.import(dummy_binding, directive);
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self.per_ns(|this, ns| {
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let _ = this.try_define(directive.parent, target, ns, dummy_binding);
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});
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}
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}
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}
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pub struct ImportResolver<'a, 'b: 'a> {
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pub resolver: &'a mut Resolver<'b>,
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}
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impl<'a, 'b: 'a> ::std::ops::Deref for ImportResolver<'a, 'b> {
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type Target = Resolver<'b>;
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fn deref(&self) -> &Resolver<'b> {
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self.resolver
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}
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}
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impl<'a, 'b: 'a> ::std::ops::DerefMut for ImportResolver<'a, 'b> {
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fn deref_mut(&mut self) -> &mut Resolver<'b> {
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self.resolver
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}
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}
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impl<'a, 'b: 'a> ty::DefIdTree for &'a ImportResolver<'a, 'b> {
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fn parent(self, id: DefId) -> Option<DefId> {
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self.resolver.parent(id)
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}
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}
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impl<'a, 'b:'a> ImportResolver<'a, 'b> {
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// Import resolution
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//
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// This is a fixed-point algorithm. We resolve imports until our efforts
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// are stymied by an unresolved import; then we bail out of the current
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// module and continue. We terminate successfully once no more imports
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// remain or unsuccessfully when no forward progress in resolving imports
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// is made.
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|
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/// Resolves all imports for the crate. This method performs the fixed-
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/// point iteration.
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pub fn resolve_imports(&mut self) {
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let mut prev_num_indeterminates = self.indeterminate_imports.len() + 1;
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while self.indeterminate_imports.len() < prev_num_indeterminates {
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prev_num_indeterminates = self.indeterminate_imports.len();
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for import in mem::replace(&mut self.indeterminate_imports, Vec::new()) {
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match self.resolve_import(&import) {
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true => self.determined_imports.push(import),
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false => self.indeterminate_imports.push(import),
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}
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}
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}
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}
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pub fn finalize_imports(&mut self) {
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for module in self.arenas.local_modules().iter() {
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self.finalize_resolutions_in(module);
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}
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|
|
|
let mut errors = false;
|
|
let mut seen_spans = FxHashSet();
|
|
for i in 0 .. self.determined_imports.len() {
|
|
let import = self.determined_imports[i];
|
|
if let Some((span, err)) = self.finalize_import(import) {
|
|
errors = true;
|
|
|
|
if let SingleImport { source, ref result, .. } = import.subclass {
|
|
if source.name == "self" {
|
|
// Silence `unresolved import` error if E0429 is already emitted
|
|
match result.value_ns.get() {
|
|
Err(Determined) => continue,
|
|
_ => {},
|
|
}
|
|
}
|
|
}
|
|
|
|
// If the error is a single failed import then create a "fake" import
|
|
// resolution for it so that later resolve stages won't complain.
|
|
self.import_dummy_binding(import);
|
|
if !seen_spans.contains(&span) {
|
|
let path = import_path_to_string(&import.module_path[..],
|
|
&import.subclass,
|
|
span);
|
|
let error = ResolutionError::UnresolvedImport(Some((span, &path, &err)));
|
|
resolve_error(self.resolver, span, error);
|
|
seen_spans.insert(span);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Report unresolved imports only if no hard error was already reported
|
|
// to avoid generating multiple errors on the same import.
|
|
if !errors {
|
|
if let Some(import) = self.indeterminate_imports.iter().next() {
|
|
let error = ResolutionError::UnresolvedImport(None);
|
|
resolve_error(self.resolver, import.span, error);
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Attempts to resolve the given import, returning true if its resolution is determined.
|
|
/// If successful, the resolved bindings are written into the module.
|
|
fn resolve_import(&mut self, directive: &'b ImportDirective<'b>) -> bool {
|
|
debug!("(resolving import for module) resolving import `{}::...` in `{}`",
|
|
names_to_string(&directive.module_path[..]),
|
|
module_to_string(self.current_module));
|
|
|
|
self.current_module = directive.parent;
|
|
|
|
let module = if let Some(module) = directive.imported_module.get() {
|
|
module
|
|
} else {
|
|
let vis = directive.vis.get();
|
|
// For better failure detection, pretend that the import will not define any names
|
|
// while resolving its module path.
|
|
directive.vis.set(ty::Visibility::Invisible);
|
|
let result = self.resolve_path(&directive.module_path[..], None, false, directive.span);
|
|
directive.vis.set(vis);
|
|
|
|
match result {
|
|
PathResult::Module(module) => module,
|
|
PathResult::Indeterminate => return false,
|
|
_ => return true,
|
|
}
|
|
};
|
|
|
|
directive.imported_module.set(Some(module));
|
|
let (source, target, result, type_ns_only) = match directive.subclass {
|
|
SingleImport { source, target, ref result, type_ns_only } =>
|
|
(source, target, result, type_ns_only),
|
|
GlobImport { .. } => {
|
|
self.resolve_glob_import(directive);
|
|
return true;
|
|
}
|
|
_ => unreachable!(),
|
|
};
|
|
|
|
let mut indeterminate = false;
|
|
self.per_ns(|this, ns| if !type_ns_only || ns == TypeNS {
|
|
if let Err(Undetermined) = result[ns].get() {
|
|
result[ns].set(this.resolve_ident_in_module(module,
|
|
source,
|
|
ns,
|
|
false,
|
|
false,
|
|
directive.span));
|
|
} else {
|
|
return
|
|
};
|
|
|
|
let parent = directive.parent;
|
|
match result[ns].get() {
|
|
Err(Undetermined) => indeterminate = true,
|
|
Err(Determined) => {
|
|
this.update_resolution(parent, target, ns, |_, resolution| {
|
|
resolution.single_imports.directive_failed()
|
|
});
|
|
}
|
|
Ok(binding) if !binding.is_importable() => {
|
|
let msg = format!("`{}` is not directly importable", target);
|
|
struct_span_err!(this.session, directive.span, E0253, "{}", &msg)
|
|
.span_label(directive.span, "cannot be imported directly")
|
|
.emit();
|
|
// Do not import this illegal binding. Import a dummy binding and pretend
|
|
// everything is fine
|
|
this.import_dummy_binding(directive);
|
|
}
|
|
Ok(binding) => {
|
|
let imported_binding = this.import(binding, directive);
|
|
let conflict = this.try_define(parent, target, ns, imported_binding);
|
|
if let Err(old_binding) = conflict {
|
|
this.report_conflict(parent, target, ns, imported_binding, old_binding);
|
|
}
|
|
}
|
|
}
|
|
});
|
|
|
|
!indeterminate
|
|
}
|
|
|
|
// If appropriate, returns an error to report.
|
|
fn finalize_import(&mut self, directive: &'b ImportDirective<'b>) -> Option<(Span, String)> {
|
|
self.current_module = directive.parent;
|
|
|
|
let ImportDirective { ref module_path, span, .. } = *directive;
|
|
let module_result = self.resolve_path(&module_path, None, true, span);
|
|
let module = match module_result {
|
|
PathResult::Module(module) => module,
|
|
PathResult::Failed(span, msg, _) => {
|
|
let (mut self_path, mut self_result) = (module_path.clone(), None);
|
|
if !self_path.is_empty() &&
|
|
!token::Ident(self_path[0].node).is_path_segment_keyword()
|
|
{
|
|
self_path[0].node.name = keywords::SelfValue.name();
|
|
self_result = Some(self.resolve_path(&self_path, None, false, span));
|
|
}
|
|
return if let Some(PathResult::Module(..)) = self_result {
|
|
Some((span, format!("Did you mean `{}`?", names_to_string(&self_path[..]))))
|
|
} else {
|
|
Some((span, msg))
|
|
};
|
|
},
|
|
_ => return None,
|
|
};
|
|
|
|
let (ident, result, type_ns_only) = match directive.subclass {
|
|
SingleImport { source, ref result, type_ns_only, .. } => (source, result, type_ns_only),
|
|
GlobImport { .. } if module.def_id() == directive.parent.def_id() => {
|
|
// Importing a module into itself is not allowed.
|
|
return Some((directive.span,
|
|
"Cannot glob-import a module into itself.".to_string()));
|
|
}
|
|
GlobImport { is_prelude, ref max_vis } => {
|
|
if !is_prelude &&
|
|
max_vis.get() != ty::Visibility::Invisible && // Allow empty globs.
|
|
!max_vis.get().is_at_least(directive.vis.get(), &*self) {
|
|
let msg = "A non-empty glob must import something with the glob's visibility";
|
|
self.session.span_err(directive.span, msg);
|
|
}
|
|
return None;
|
|
}
|
|
_ => unreachable!(),
|
|
};
|
|
|
|
let mut all_ns_err = true;
|
|
let mut legacy_self_import = None;
|
|
self.per_ns(|this, ns| if !type_ns_only || ns == TypeNS {
|
|
if let Ok(binding) = result[ns].get() {
|
|
all_ns_err = false;
|
|
if this.record_use(ident, ns, binding, directive.span) {
|
|
this.resolution(module, ident, ns).borrow_mut().binding =
|
|
Some(this.dummy_binding);
|
|
}
|
|
}
|
|
} else if let Ok(binding) = this.resolve_ident_in_module(module,
|
|
ident,
|
|
ns,
|
|
false,
|
|
false,
|
|
directive.span) {
|
|
legacy_self_import = Some(directive);
|
|
let binding = this.arenas.alloc_name_binding(NameBinding {
|
|
kind: NameBindingKind::Import {
|
|
binding: binding,
|
|
directive: directive,
|
|
used: Cell::new(false),
|
|
legacy_self_import: true,
|
|
},
|
|
..*binding
|
|
});
|
|
let _ = this.try_define(directive.parent, ident, ns, binding);
|
|
});
|
|
|
|
if all_ns_err {
|
|
if let Some(directive) = legacy_self_import {
|
|
self.warn_legacy_self_import(directive);
|
|
return None;
|
|
}
|
|
let mut all_ns_failed = true;
|
|
self.per_ns(|this, ns| if !type_ns_only || ns == TypeNS {
|
|
match this.resolve_ident_in_module(module, ident, ns, false, true, span) {
|
|
Ok(_) => all_ns_failed = false,
|
|
_ => {}
|
|
}
|
|
});
|
|
|
|
return if all_ns_failed {
|
|
let resolutions = module.resolutions.borrow();
|
|
let names = resolutions.iter().filter_map(|(&(ref i, _), resolution)| {
|
|
if *i == ident { return None; } // Never suggest the same name
|
|
match *resolution.borrow() {
|
|
NameResolution { binding: Some(name_binding), .. } => {
|
|
match name_binding.kind {
|
|
NameBindingKind::Import { binding, .. } => {
|
|
match binding.kind {
|
|
// Never suggest the name that has binding error
|
|
// i.e. the name that cannot be previously resolved
|
|
NameBindingKind::Def(Def::Err) => return None,
|
|
_ => Some(&i.name),
|
|
}
|
|
},
|
|
_ => Some(&i.name),
|
|
}
|
|
},
|
|
NameResolution { single_imports: SingleImports::None, .. } => None,
|
|
_ => Some(&i.name),
|
|
}
|
|
});
|
|
let lev_suggestion =
|
|
match find_best_match_for_name(names, &ident.name.as_str(), None) {
|
|
Some(name) => format!(". Did you mean to use `{}`?", name),
|
|
None => "".to_owned(),
|
|
};
|
|
let module_str = module_to_string(module);
|
|
let msg = if &module_str == "???" {
|
|
format!("no `{}` in the root{}", ident, lev_suggestion)
|
|
} else {
|
|
format!("no `{}` in `{}`{}", ident, module_str, lev_suggestion)
|
|
};
|
|
Some((span, msg))
|
|
} else {
|
|
// `resolve_ident_in_module` reported a privacy error.
|
|
self.import_dummy_binding(directive);
|
|
None
|
|
}
|
|
}
|
|
|
|
let mut reexport_error = None;
|
|
let mut any_successful_reexport = false;
|
|
self.per_ns(|this, ns| {
|
|
if let Ok(binding) = result[ns].get() {
|
|
let vis = directive.vis.get();
|
|
if !binding.pseudo_vis().is_at_least(vis, &*this) {
|
|
reexport_error = Some((ns, binding));
|
|
} else {
|
|
any_successful_reexport = true;
|
|
}
|
|
}
|
|
});
|
|
|
|
// All namespaces must be re-exported with extra visibility for an error to occur.
|
|
if !any_successful_reexport {
|
|
let (ns, binding) = reexport_error.unwrap();
|
|
if ns == TypeNS && binding.is_extern_crate() {
|
|
let msg = format!("extern crate `{}` is private, and cannot be reexported \
|
|
(error E0365), consider declaring with `pub`",
|
|
ident);
|
|
self.session.add_lint(PUB_USE_OF_PRIVATE_EXTERN_CRATE,
|
|
directive.id, directive.span, msg);
|
|
} else if ns == TypeNS {
|
|
struct_span_err!(self.session, directive.span, E0365,
|
|
"`{}` is private, and cannot be reexported", ident)
|
|
.span_label(directive.span, format!("reexport of private `{}`", ident))
|
|
.note(&format!("consider declaring type or module `{}` with `pub`", ident))
|
|
.emit();
|
|
} else {
|
|
let msg = format!("`{}` is private, and cannot be reexported", ident);
|
|
let note_msg =
|
|
format!("consider marking `{}` as `pub` in the imported module", ident);
|
|
struct_span_err!(self.session, directive.span, E0364, "{}", &msg)
|
|
.span_note(directive.span, ¬e_msg)
|
|
.emit();
|
|
}
|
|
}
|
|
|
|
// 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.
|
|
self.per_ns(|this, ns| if let Some(binding) = result[ns].get().ok() {
|
|
this.def_map.entry(directive.id).or_insert(PathResolution::new(binding.def()));
|
|
});
|
|
|
|
debug!("(resolving single import) successfully resolved import");
|
|
None
|
|
}
|
|
|
|
fn resolve_glob_import(&mut self, directive: &'b ImportDirective<'b>) {
|
|
let module = directive.imported_module.get().unwrap();
|
|
self.populate_module_if_necessary(module);
|
|
|
|
if let Some(Def::Trait(_)) = module.def() {
|
|
self.session.span_err(directive.span, "items in traits are not importable.");
|
|
return;
|
|
} else if module.def_id() == directive.parent.def_id() {
|
|
return;
|
|
} else if let GlobImport { is_prelude: true, .. } = directive.subclass {
|
|
self.prelude = Some(module);
|
|
return;
|
|
}
|
|
|
|
// Add to module's glob_importers
|
|
module.glob_importers.borrow_mut().push(directive);
|
|
|
|
// Ensure that `resolutions` isn't borrowed during `try_define`,
|
|
// since it might get updated via a glob cycle.
|
|
let bindings = module.resolutions.borrow().iter().filter_map(|(&ident, resolution)| {
|
|
resolution.borrow().binding().map(|binding| (ident, binding))
|
|
}).collect::<Vec<_>>();
|
|
for ((mut ident, ns), binding) in bindings {
|
|
let scope = match ident.ctxt.reverse_glob_adjust(module.expansion,
|
|
directive.span.ctxt.modern()) {
|
|
Some(Some(def)) => self.macro_def_scope(def),
|
|
Some(None) => self.current_module,
|
|
None => continue,
|
|
};
|
|
if self.is_accessible_from(binding.pseudo_vis(), scope) {
|
|
let imported_binding = self.import(binding, directive);
|
|
let _ = self.try_define(directive.parent, ident, ns, imported_binding);
|
|
}
|
|
}
|
|
|
|
// Record the destination of this import
|
|
self.record_def(directive.id, PathResolution::new(module.def().unwrap()));
|
|
}
|
|
|
|
// Miscellaneous post-processing, including recording reexports,
|
|
// reporting conflicts, and reporting unresolved imports.
|
|
fn finalize_resolutions_in(&mut self, module: Module<'b>) {
|
|
// Since import resolution is finished, globs will not define any more names.
|
|
*module.globs.borrow_mut() = Vec::new();
|
|
|
|
let mut reexports = Vec::new();
|
|
let mut exported_macro_names = FxHashMap();
|
|
if module as *const _ == self.graph_root as *const _ {
|
|
let macro_exports = mem::replace(&mut self.macro_exports, Vec::new());
|
|
for export in macro_exports.into_iter().rev() {
|
|
if exported_macro_names.insert(export.ident.modern(), export.span).is_none() {
|
|
reexports.push(export);
|
|
}
|
|
}
|
|
}
|
|
|
|
for (&(ident, ns), resolution) in module.resolutions.borrow().iter() {
|
|
let resolution = &mut *resolution.borrow_mut();
|
|
let binding = match resolution.binding {
|
|
Some(binding) => binding,
|
|
None => continue,
|
|
};
|
|
|
|
if binding.vis == ty::Visibility::Public &&
|
|
(binding.is_import() || binding.is_macro_def()) {
|
|
let def = binding.def();
|
|
if def != Def::Err {
|
|
if !def.def_id().is_local() {
|
|
self.session.cstore.export_macros(def.def_id().krate);
|
|
}
|
|
if let Def::Macro(..) = def {
|
|
if let Some(&span) = exported_macro_names.get(&ident.modern()) {
|
|
let msg =
|
|
format!("a macro named `{}` has already been exported", ident);
|
|
self.session.struct_span_err(span, &msg)
|
|
.span_label(span, format!("`{}` already exported", ident))
|
|
.span_note(binding.span, "previous macro export here")
|
|
.emit();
|
|
}
|
|
}
|
|
reexports.push(Export { ident: ident.modern(), def: def, span: binding.span });
|
|
}
|
|
}
|
|
|
|
match binding.kind {
|
|
NameBindingKind::Import { binding: orig_binding, .. } => {
|
|
if ns == TypeNS && orig_binding.is_variant() &&
|
|
!orig_binding.vis.is_at_least(binding.vis, &*self) {
|
|
let msg = format!("variant `{}` is private, and cannot be reexported, \
|
|
consider declaring its enum as `pub`", ident);
|
|
self.session.span_err(binding.span, &msg);
|
|
}
|
|
}
|
|
NameBindingKind::Ambiguity { b1, b2, .. }
|
|
if b1.is_glob_import() && b2.is_glob_import() => {
|
|
let (orig_b1, orig_b2) = match (&b1.kind, &b2.kind) {
|
|
(&NameBindingKind::Import { binding: b1, .. },
|
|
&NameBindingKind::Import { binding: b2, .. }) => (b1, b2),
|
|
_ => continue,
|
|
};
|
|
let (b1, b2) = match (orig_b1.vis, orig_b2.vis) {
|
|
(ty::Visibility::Public, ty::Visibility::Public) => continue,
|
|
(ty::Visibility::Public, _) => (b1, b2),
|
|
(_, ty::Visibility::Public) => (b2, b1),
|
|
_ => continue,
|
|
};
|
|
resolution.binding = Some(self.arenas.alloc_name_binding(NameBinding {
|
|
kind: NameBindingKind::Ambiguity { b1: b1, b2: b2, legacy: true }, ..*b1
|
|
}));
|
|
}
|
|
_ => {}
|
|
}
|
|
}
|
|
|
|
if reexports.len() > 0 {
|
|
if let Some(def_id) = module.def_id() {
|
|
let node_id = self.definitions.as_local_node_id(def_id).unwrap();
|
|
self.export_map.insert(node_id, reexports);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn import_path_to_string(names: &[SpannedIdent],
|
|
subclass: &ImportDirectiveSubclass,
|
|
span: Span) -> String {
|
|
let pos = names.iter()
|
|
.position(|p| span == p.span && p.node.name != keywords::CrateRoot.name());
|
|
let global = !names.is_empty() && names[0].node.name == keywords::CrateRoot.name();
|
|
if let Some(pos) = pos {
|
|
let names = if global { &names[1..pos + 1] } else { &names[..pos + 1] };
|
|
names_to_string(names)
|
|
} else {
|
|
let names = if global { &names[1..] } else { names };
|
|
if names.is_empty() {
|
|
import_directive_subclass_to_string(subclass)
|
|
} else {
|
|
(format!("{}::{}",
|
|
names_to_string(names),
|
|
import_directive_subclass_to_string(subclass)))
|
|
}
|
|
}
|
|
}
|
|
|
|
fn import_directive_subclass_to_string(subclass: &ImportDirectiveSubclass) -> String {
|
|
match *subclass {
|
|
SingleImport { source, .. } => source.to_string(),
|
|
GlobImport { .. } => "*".to_string(),
|
|
ExternCrate => "<extern crate>".to_string(),
|
|
MacroUse => "#[macro_use]".to_string(),
|
|
}
|
|
}
|