1521 lines
63 KiB
Rust
1521 lines
63 KiB
Rust
//! A bunch of methods and structures more or less related to resolving imports.
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use ImportDirectiveSubclass::*;
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use crate::diagnostics::Suggestion;
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use crate::Determinacy::{self, *};
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use crate::Namespace::{self, MacroNS, TypeNS};
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use crate::{module_to_string, names_to_string};
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use crate::{AmbiguityError, AmbiguityErrorMisc, AmbiguityKind};
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use crate::{BindingKey, ModuleKind, ResolutionError, Resolver, Segment};
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use crate::{CrateLint, Module, ModuleOrUniformRoot, ParentScope, PerNS, ScopeSet, Weak};
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use crate::{NameBinding, NameBindingKind, PathResult, PrivacyError, ToNameBinding};
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use rustc::hir::exports::Export;
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use rustc::lint::builtin::{PUB_USE_OF_PRIVATE_EXTERN_CRATE, UNUSED_IMPORTS};
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use rustc::ty;
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use rustc::{bug, span_bug};
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use rustc_data_structures::fx::FxHashSet;
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use rustc_data_structures::ptr_key::PtrKey;
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use rustc_errors::{pluralize, struct_span_err, Applicability};
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use rustc_hir::def::{self, PartialRes};
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use rustc_hir::def_id::DefId;
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use rustc_session::lint::BuiltinLintDiagnostics;
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use rustc_session::DiagnosticMessageId;
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use rustc_span::hygiene::ExpnId;
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use rustc_span::symbol::kw;
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use rustc_span::{MultiSpan, Span};
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use syntax::ast::{Ident, Name, NodeId};
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use syntax::unwrap_or;
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use syntax::util::lev_distance::find_best_match_for_name;
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use log::*;
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use std::cell::Cell;
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use std::{mem, ptr};
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type Res = def::Res<NodeId>;
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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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/// `source` in `use prefix::source as target`.
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source: Ident,
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/// `target` in `use prefix::source as target`.
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target: Ident,
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/// Bindings to which `source` refers to.
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source_bindings: PerNS<Cell<Result<&'a NameBinding<'a>, Determinacy>>>,
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/// Bindings introduced by `target`.
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target_bindings: PerNS<Cell<Option<&'a NameBinding<'a>>>>,
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/// `true` for `...::{self [as target]}` imports, `false` otherwise.
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type_ns_only: bool,
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/// Did this import result from a nested import? ie. `use foo::{bar, baz};`
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nested: 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 re-export.
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// n.b. `max_vis` is only used in `finalize_import` to check for re-export errors.
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},
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ExternCrate {
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source: Option<Name>,
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target: Ident,
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},
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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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crate struct ImportDirective<'a> {
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/// The ID of the `extern crate`, `UseTree` etc that imported this `ImportDirective`.
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///
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/// In the case where the `ImportDirective` was expanded from a "nested" use tree,
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/// this id is the ID of the leaf tree. For example:
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///
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/// ```ignore (pacify the mercilous tidy)
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/// use foo::bar::{a, b}
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/// ```
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///
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/// If this is the import directive for `foo::bar::a`, we would have the ID of the `UseTree`
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/// for `a` in this field.
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pub id: NodeId,
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/// The `id` of the "root" use-kind -- this is always the same as
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/// `id` except in the case of "nested" use trees, in which case
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/// it will be the `id` of the root use tree. e.g., in the example
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/// from `id`, this would be the ID of the `use foo::bar`
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/// `UseTree` node.
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pub root_id: NodeId,
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/// Span of the entire use statement.
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pub use_span: Span,
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/// Span of the entire use statement with attributes.
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pub use_span_with_attributes: Span,
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/// Did the use statement have any attributes?
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pub has_attributes: bool,
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/// Span of this use tree.
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pub span: Span,
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/// Span of the *root* use tree (see `root_id`).
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pub root_span: Span,
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pub parent_scope: ParentScope<'a>,
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pub module_path: Vec<Segment>,
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/// The resolution of `module_path`.
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pub imported_module: Cell<Option<ModuleOrUniformRoot<'a>>>,
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pub subclass: ImportDirectiveSubclass<'a>,
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pub vis: Cell<ty::Visibility>,
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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 {
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ImportDirectiveSubclass::GlobImport { .. } => true,
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_ => false,
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}
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}
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pub fn is_nested(&self) -> bool {
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match self.subclass {
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ImportDirectiveSubclass::SingleImport { nested, .. } => nested,
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_ => false,
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}
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}
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crate fn crate_lint(&self) -> CrateLint {
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CrateLint::UsePath { root_id: self.root_id, root_span: self.root_span }
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}
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}
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#[derive(Clone, Default, Debug)]
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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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/// Single imports that may define the name in the namespace.
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/// Import directives are arena-allocated, so it's ok to use pointers as keys.
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single_imports: FxHashSet<PtrKey<'a, ImportDirective<'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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shadowed_glob: Option<&'a NameBinding<'a>>,
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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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pub(crate) fn binding(&self) -> Option<&'a NameBinding<'a>> {
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self.binding.and_then(|binding| {
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if !binding.is_glob_import() || self.single_imports.is_empty() {
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Some(binding)
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} else {
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None
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}
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})
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}
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crate fn add_single_import(&mut self, directive: &'a ImportDirective<'a>) {
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self.single_imports.insert(PtrKey(directive));
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}
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}
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impl<'a> Resolver<'a> {
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crate fn resolve_ident_in_module_unadjusted(
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&mut self,
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module: ModuleOrUniformRoot<'a>,
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ident: Ident,
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ns: Namespace,
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parent_scope: &ParentScope<'a>,
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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.resolve_ident_in_module_unadjusted_ext(
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module,
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ident,
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ns,
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parent_scope,
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false,
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record_used,
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path_span,
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)
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.map_err(|(determinacy, _)| determinacy)
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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`, expansion and import resolution must be complete.
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crate fn resolve_ident_in_module_unadjusted_ext(
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&mut self,
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module: ModuleOrUniformRoot<'a>,
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ident: Ident,
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ns: Namespace,
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parent_scope: &ParentScope<'a>,
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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, Weak)> {
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let module = match module {
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ModuleOrUniformRoot::Module(module) => module,
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ModuleOrUniformRoot::CrateRootAndExternPrelude => {
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assert!(!restricted_shadowing);
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let binding = self.early_resolve_ident_in_lexical_scope(
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ident,
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ScopeSet::AbsolutePath(ns),
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parent_scope,
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record_used,
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record_used,
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path_span,
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);
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return binding.map_err(|determinacy| (determinacy, Weak::No));
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}
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ModuleOrUniformRoot::ExternPrelude => {
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assert!(!restricted_shadowing);
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return if ns != TypeNS {
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Err((Determined, Weak::No))
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} else if let Some(binding) = self.extern_prelude_get(ident, !record_used) {
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Ok(binding)
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} else if !self.graph_root.unexpanded_invocations.borrow().is_empty() {
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// Macro-expanded `extern crate` items can add names to extern prelude.
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Err((Undetermined, Weak::No))
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} else {
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Err((Determined, Weak::No))
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};
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}
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ModuleOrUniformRoot::CurrentScope => {
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assert!(!restricted_shadowing);
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if ns == TypeNS {
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if ident.name == kw::Crate || ident.name == kw::DollarCrate {
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let module = self.resolve_crate_root(ident);
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let binding = (module, ty::Visibility::Public, module.span, ExpnId::root())
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.to_name_binding(self.arenas);
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return Ok(binding);
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} else if ident.name == kw::Super || ident.name == kw::SelfLower {
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// FIXME: Implement these with renaming requirements so that e.g.
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// `use super;` doesn't work, but `use super as name;` does.
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// Fall through here to get an error from `early_resolve_...`.
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}
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}
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let scopes = ScopeSet::All(ns, true);
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let binding = self.early_resolve_ident_in_lexical_scope(
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ident,
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scopes,
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parent_scope,
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record_used,
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record_used,
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path_span,
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);
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return binding.map_err(|determinacy| (determinacy, Weak::No));
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}
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};
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let key = self.new_key(ident, ns);
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let resolution =
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self.resolution(module, key).try_borrow_mut().map_err(|_| (Determined, Weak::No))?; // This happens when there is a cycle of imports.
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if let Some(binding) = resolution.binding {
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if !restricted_shadowing && binding.expansion != ExpnId::root() {
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if let NameBindingKind::Res(_, true) = binding.kind {
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self.macro_expanded_macro_export_errors.insert((path_span, binding.span));
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}
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}
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}
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let check_usable = |this: &mut Self, binding: &'a NameBinding<'a>| {
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if let Some(blacklisted_binding) = this.blacklisted_binding {
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if ptr::eq(binding, blacklisted_binding) {
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return Err((Determined, Weak::No));
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}
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}
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// `extern crate` are always usable for backwards compatibility, see issue #37020,
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// remove this together with `PUB_USE_OF_PRIVATE_EXTERN_CRATE`.
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let usable = this.is_accessible_from(binding.vis, parent_scope.module)
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|| binding.is_extern_crate();
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if usable { Ok(binding) } else { Err((Determined, Weak::No)) }
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};
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if record_used {
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return resolution
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.binding
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.and_then(|binding| {
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// If the primary binding is blacklisted, search further and return the shadowed
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// glob binding if it exists. What we really want here is having two separate
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// scopes in a module - one for non-globs and one for globs, but until that's done
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// use this hack to avoid inconsistent resolution ICEs during import validation.
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if let Some(blacklisted_binding) = self.blacklisted_binding {
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if ptr::eq(binding, blacklisted_binding) {
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return resolution.shadowed_glob;
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}
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}
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Some(binding)
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})
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.ok_or((Determined, Weak::No))
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.and_then(|binding| {
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if self.last_import_segment && check_usable(self, binding).is_err() {
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Err((Determined, Weak::No))
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} else {
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self.record_use(ident, ns, binding, restricted_shadowing);
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if let Some(shadowed_glob) = resolution.shadowed_glob {
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// Forbid expanded shadowing to avoid time travel.
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if restricted_shadowing
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&& binding.expansion != ExpnId::root()
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&& binding.res() != shadowed_glob.res()
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{
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self.ambiguity_errors.push(AmbiguityError {
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kind: AmbiguityKind::GlobVsExpanded,
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ident,
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b1: binding,
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b2: shadowed_glob,
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misc1: AmbiguityErrorMisc::None,
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misc2: AmbiguityErrorMisc::None,
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});
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}
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}
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if !self.is_accessible_from(binding.vis, parent_scope.module) &&
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// Remove this together with `PUB_USE_OF_PRIVATE_EXTERN_CRATE`
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!(self.last_import_segment && binding.is_extern_crate())
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{
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self.privacy_errors.push(PrivacyError {
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ident,
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binding,
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dedup_span: path_span,
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});
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}
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Ok(binding)
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}
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});
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}
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// Items and single imports are not shadowable, if we have one, then it's determined.
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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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// --- From now on we either have a glob resolution or no resolution. ---
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// Check if one of single imports can still define the name,
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// if it can then our result is not determined and can be invalidated.
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for single_import in &resolution.single_imports {
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if !self.is_accessible_from(single_import.vis.get(), parent_scope.module) {
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continue;
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}
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let module = unwrap_or!(
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single_import.imported_module.get(),
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return Err((Undetermined, Weak::No))
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);
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let ident = match single_import.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(
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module,
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ident,
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ns,
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&single_import.parent_scope,
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false,
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path_span,
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) {
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Err(Determined) => continue,
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Ok(binding)
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if !self.is_accessible_from(binding.vis, single_import.parent_scope.module) =>
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{
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continue;
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}
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Ok(_) | Err(Undetermined) => return Err((Undetermined, Weak::No)),
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}
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}
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// So we have a resolution that's from a glob import. This resolution is determined
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// if it cannot be shadowed by some new item/import expanded from a macro.
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// This happens either if there are no unexpanded macros, or expanded names cannot
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// shadow globs (that happens in macro namespace or with restricted shadowing).
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//
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// Additionally, any macro in any module can plant names in the root module if it creates
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// `macro_export` macros, so the root module effectively has unresolved invocations if any
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// module has unresolved invocations.
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// However, it causes resolution/expansion to stuck too often (#53144), so, to make
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// progress, we have to ignore those potential unresolved invocations from other modules
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// and prohibit access to macro-expanded `macro_export` macros instead (unless restricted
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// shadowing is enabled, see `macro_expanded_macro_export_errors`).
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let unexpanded_macros = !module.unexpanded_invocations.borrow().is_empty();
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if let Some(binding) = resolution.binding {
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if !unexpanded_macros || ns == MacroNS || restricted_shadowing {
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return check_usable(self, binding);
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} else {
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return Err((Undetermined, Weak::No));
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}
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}
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// --- From now on we have no resolution. ---
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// Now we are in situation when new item/import can appear only from a glob or a macro
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// expansion. With restricted shadowing names from globs and macro expansions cannot
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// shadow names from outer scopes, so we can freely fallback from module search to search
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// in outer scopes. For `early_resolve_ident_in_lexical_scope` to continue search in outer
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// scopes we return `Undetermined` with `Weak::Yes`.
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// Check if one of unexpanded macros can still define the name,
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// if it can then our "no resolution" result is not determined and can be invalidated.
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if unexpanded_macros {
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return Err((Undetermined, Weak::Yes));
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}
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|
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// Check if one of glob imports can still define the name,
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// if it can then our "no resolution" result is not determined and can be invalidated.
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for glob_import in module.globs.borrow().iter() {
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if !self.is_accessible_from(glob_import.vis.get(), parent_scope.module) {
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continue;
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}
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let module = match glob_import.imported_module.get() {
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Some(ModuleOrUniformRoot::Module(module)) => module,
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Some(_) => continue,
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None => return Err((Undetermined, Weak::Yes)),
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};
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let tmp_parent_scope;
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let (mut adjusted_parent_scope, mut ident) = (parent_scope, ident.modern());
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match ident.span.glob_adjust(module.expansion, glob_import.span) {
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Some(Some(def)) => {
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tmp_parent_scope =
|
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ParentScope { module: self.macro_def_scope(def), ..*parent_scope };
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adjusted_parent_scope = &tmp_parent_scope;
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}
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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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ModuleOrUniformRoot::Module(module),
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ident,
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ns,
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adjusted_parent_scope,
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false,
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path_span,
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);
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|
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match result {
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Err(Determined) => continue,
|
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Ok(binding)
|
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if !self.is_accessible_from(binding.vis, glob_import.parent_scope.module) =>
|
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{
|
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continue;
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}
|
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Ok(_) | Err(Undetermined) => return Err((Undetermined, Weak::Yes)),
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}
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}
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|
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// No resolution and no one else can define the name - determinate error.
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Err((Determined, Weak::No))
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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.
|
|
crate fn import(
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&self,
|
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binding: &'a NameBinding<'a>,
|
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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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// cf. `PUB_USE_OF_PRIVATE_EXTERN_CRATE`
|
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!directive.is_glob() && binding.is_extern_crate()
|
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{
|
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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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|
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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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|
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self.arenas.alloc_name_binding(NameBinding {
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kind: NameBindingKind::Import { binding, directive, used: Cell::new(false) },
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ambiguity: None,
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span: directive.span,
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vis,
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expansion: directive.parent_scope.expansion,
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})
|
|
}
|
|
|
|
// Define the name or return the existing binding if there is a collision.
|
|
crate fn try_define(
|
|
&mut self,
|
|
module: Module<'a>,
|
|
key: BindingKey,
|
|
binding: &'a NameBinding<'a>,
|
|
) -> Result<(), &'a NameBinding<'a>> {
|
|
let res = binding.res();
|
|
self.check_reserved_macro_name(key.ident, res);
|
|
self.set_binding_parent_module(binding, module);
|
|
self.update_resolution(module, key, |this, resolution| {
|
|
if let Some(old_binding) = resolution.binding {
|
|
if res == Res::Err {
|
|
// Do not override real bindings with `Res::Err`s from error recovery.
|
|
return Ok(());
|
|
}
|
|
match (old_binding.is_glob_import(), binding.is_glob_import()) {
|
|
(true, true) => {
|
|
if res != old_binding.res() {
|
|
resolution.binding = Some(this.ambiguity(
|
|
AmbiguityKind::GlobVsGlob,
|
|
old_binding,
|
|
binding,
|
|
));
|
|
} else if !old_binding.vis.is_at_least(binding.vis, &*this) {
|
|
// We are glob-importing the same item but with greater visibility.
|
|
resolution.binding = Some(binding);
|
|
}
|
|
}
|
|
(old_glob @ true, false) | (old_glob @ false, true) => {
|
|
let (glob_binding, nonglob_binding) =
|
|
if old_glob { (old_binding, binding) } else { (binding, old_binding) };
|
|
if glob_binding.res() != nonglob_binding.res()
|
|
&& key.ns == MacroNS
|
|
&& nonglob_binding.expansion != ExpnId::root()
|
|
{
|
|
resolution.binding = Some(this.ambiguity(
|
|
AmbiguityKind::GlobVsExpanded,
|
|
nonglob_binding,
|
|
glob_binding,
|
|
));
|
|
} else {
|
|
resolution.binding = Some(nonglob_binding);
|
|
}
|
|
resolution.shadowed_glob = Some(glob_binding);
|
|
}
|
|
(false, false) => {
|
|
return Err(old_binding);
|
|
}
|
|
}
|
|
} else {
|
|
resolution.binding = Some(binding);
|
|
}
|
|
|
|
Ok(())
|
|
})
|
|
}
|
|
|
|
fn ambiguity(
|
|
&self,
|
|
kind: AmbiguityKind,
|
|
primary_binding: &'a NameBinding<'a>,
|
|
secondary_binding: &'a NameBinding<'a>,
|
|
) -> &'a NameBinding<'a> {
|
|
self.arenas.alloc_name_binding(NameBinding {
|
|
ambiguity: Some((secondary_binding, kind)),
|
|
..primary_binding.clone()
|
|
})
|
|
}
|
|
|
|
// Use `f` to mutate the resolution of the name in the module.
|
|
// If the resolution becomes a success, define it in the module's glob importers.
|
|
fn update_resolution<T, F>(&mut self, module: Module<'a>, key: BindingKey, f: F) -> T
|
|
where
|
|
F: FnOnce(&mut Resolver<'a>, &mut NameResolution<'a>) -> T,
|
|
{
|
|
// Ensure that `resolution` isn't borrowed when defining in the module's glob importers,
|
|
// during which the resolution might end up getting re-defined via a glob cycle.
|
|
let (binding, t) = {
|
|
let resolution = &mut *self.resolution(module, key).borrow_mut();
|
|
let old_binding = resolution.binding();
|
|
|
|
let t = f(self, resolution);
|
|
|
|
match resolution.binding() {
|
|
_ if old_binding.is_some() => return t,
|
|
None => return t,
|
|
Some(binding) => match old_binding {
|
|
Some(old_binding) if ptr::eq(old_binding, binding) => return t,
|
|
_ => (binding, t),
|
|
},
|
|
}
|
|
};
|
|
|
|
// Define `binding` in `module`s glob importers.
|
|
for directive in module.glob_importers.borrow_mut().iter() {
|
|
let mut ident = key.ident;
|
|
let scope = match ident.span.reverse_glob_adjust(module.expansion, directive.span) {
|
|
Some(Some(def)) => self.macro_def_scope(def),
|
|
Some(None) => directive.parent_scope.module,
|
|
None => continue,
|
|
};
|
|
if self.is_accessible_from(binding.vis, scope) {
|
|
let imported_binding = self.import(binding, directive);
|
|
let key = BindingKey { ident, ..key };
|
|
let _ = self.try_define(directive.parent_scope.module, key, imported_binding);
|
|
}
|
|
}
|
|
|
|
t
|
|
}
|
|
|
|
// Define a "dummy" resolution containing a Res::Err as a placeholder for a
|
|
// failed resolution
|
|
fn import_dummy_binding(&mut self, directive: &'a ImportDirective<'a>) {
|
|
if let SingleImport { target, .. } = directive.subclass {
|
|
let dummy_binding = self.dummy_binding;
|
|
let dummy_binding = self.import(dummy_binding, directive);
|
|
self.per_ns(|this, ns| {
|
|
let key = this.new_key(target, ns);
|
|
let _ = this.try_define(directive.parent_scope.module, key, dummy_binding);
|
|
// Consider erroneous imports used to avoid duplicate diagnostics.
|
|
this.record_use(target, ns, dummy_binding, false);
|
|
});
|
|
}
|
|
}
|
|
}
|
|
|
|
/// An error that may be transformed into a diagnostic later. Used to combine multiple unresolved
|
|
/// import errors within the same use tree into a single diagnostic.
|
|
#[derive(Debug, Clone)]
|
|
struct UnresolvedImportError {
|
|
span: Span,
|
|
label: Option<String>,
|
|
note: Vec<String>,
|
|
suggestion: Option<Suggestion>,
|
|
}
|
|
|
|
pub struct ImportResolver<'a, 'b> {
|
|
pub r: &'a mut Resolver<'b>,
|
|
}
|
|
|
|
impl<'a, 'b> ty::DefIdTree for &'a ImportResolver<'a, 'b> {
|
|
fn parent(self, id: DefId) -> Option<DefId> {
|
|
self.r.parent(id)
|
|
}
|
|
}
|
|
|
|
impl<'a, 'b> ImportResolver<'a, 'b> {
|
|
// 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.
|
|
pub fn resolve_imports(&mut self) {
|
|
let mut prev_num_indeterminates = self.r.indeterminate_imports.len() + 1;
|
|
while self.r.indeterminate_imports.len() < prev_num_indeterminates {
|
|
prev_num_indeterminates = self.r.indeterminate_imports.len();
|
|
for import in mem::take(&mut self.r.indeterminate_imports) {
|
|
match self.resolve_import(&import) {
|
|
true => self.r.determined_imports.push(import),
|
|
false => self.r.indeterminate_imports.push(import),
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
pub fn finalize_imports(&mut self) {
|
|
for module in self.r.arenas.local_modules().iter() {
|
|
self.finalize_resolutions_in(module);
|
|
}
|
|
|
|
let mut seen_spans = FxHashSet::default();
|
|
let mut errors = vec![];
|
|
let mut prev_root_id: NodeId = NodeId::from_u32(0);
|
|
let determined_imports = mem::take(&mut self.r.determined_imports);
|
|
let indeterminate_imports = mem::take(&mut self.r.indeterminate_imports);
|
|
|
|
for (is_indeterminate, import) in determined_imports
|
|
.into_iter()
|
|
.map(|i| (false, i))
|
|
.chain(indeterminate_imports.into_iter().map(|i| (true, i)))
|
|
{
|
|
if let Some(err) = self.finalize_import(import) {
|
|
if let SingleImport { source, ref source_bindings, .. } = import.subclass {
|
|
if source.name == kw::SelfLower {
|
|
// Silence `unresolved import` error if E0429 is already emitted
|
|
if let Err(Determined) = source_bindings.value_ns.get() {
|
|
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.r.import_dummy_binding(import);
|
|
if prev_root_id.as_u32() != 0
|
|
&& prev_root_id.as_u32() != import.root_id.as_u32()
|
|
&& !errors.is_empty()
|
|
{
|
|
// In the case of a new import line, throw a diagnostic message
|
|
// for the previous line.
|
|
self.throw_unresolved_import_error(errors, None);
|
|
errors = vec![];
|
|
}
|
|
if seen_spans.insert(err.span) {
|
|
let path = import_path_to_string(
|
|
&import.module_path.iter().map(|seg| seg.ident).collect::<Vec<_>>(),
|
|
&import.subclass,
|
|
err.span,
|
|
);
|
|
errors.push((path, err));
|
|
prev_root_id = import.root_id;
|
|
}
|
|
} else if is_indeterminate {
|
|
// Consider erroneous imports used to avoid duplicate diagnostics.
|
|
self.r.used_imports.insert((import.id, TypeNS));
|
|
let path = import_path_to_string(
|
|
&import.module_path.iter().map(|seg| seg.ident).collect::<Vec<_>>(),
|
|
&import.subclass,
|
|
import.span,
|
|
);
|
|
let err = UnresolvedImportError {
|
|
span: import.span,
|
|
label: None,
|
|
note: Vec::new(),
|
|
suggestion: None,
|
|
};
|
|
errors.push((path, err));
|
|
}
|
|
}
|
|
|
|
if !errors.is_empty() {
|
|
self.throw_unresolved_import_error(errors, None);
|
|
}
|
|
}
|
|
|
|
fn throw_unresolved_import_error(
|
|
&self,
|
|
errors: Vec<(String, UnresolvedImportError)>,
|
|
span: Option<MultiSpan>,
|
|
) {
|
|
/// Upper limit on the number of `span_label` messages.
|
|
const MAX_LABEL_COUNT: usize = 10;
|
|
|
|
let (span, msg) = if errors.is_empty() {
|
|
(span.unwrap(), "unresolved import".to_string())
|
|
} else {
|
|
let span = MultiSpan::from_spans(errors.iter().map(|(_, err)| err.span).collect());
|
|
|
|
let paths = errors.iter().map(|(path, _)| format!("`{}`", path)).collect::<Vec<_>>();
|
|
|
|
let msg = format!("unresolved import{} {}", pluralize!(paths.len()), paths.join(", "),);
|
|
|
|
(span, msg)
|
|
};
|
|
|
|
let mut diag = struct_span_err!(self.r.session, span, E0432, "{}", &msg);
|
|
|
|
if let Some((_, UnresolvedImportError { note, .. })) = errors.iter().last() {
|
|
for message in note {
|
|
diag.note(&message);
|
|
}
|
|
}
|
|
|
|
for (_, err) in errors.into_iter().take(MAX_LABEL_COUNT) {
|
|
if let Some(label) = err.label {
|
|
diag.span_label(err.span, label);
|
|
}
|
|
|
|
if let Some((suggestions, msg, applicability)) = err.suggestion {
|
|
diag.multipart_suggestion(&msg, suggestions, applicability);
|
|
}
|
|
}
|
|
|
|
diag.emit();
|
|
}
|
|
|
|
/// 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 `{}`",
|
|
Segment::names_to_string(&directive.module_path),
|
|
module_to_string(directive.parent_scope.module).unwrap_or_else(|| "???".to_string()),
|
|
);
|
|
|
|
let module = if let Some(module) = directive.imported_module.get() {
|
|
module
|
|
} else {
|
|
// For better failure detection, pretend that the import will
|
|
// not define any names while resolving its module path.
|
|
let orig_vis = directive.vis.replace(ty::Visibility::Invisible);
|
|
let path_res = self.r.resolve_path(
|
|
&directive.module_path,
|
|
None,
|
|
&directive.parent_scope,
|
|
false,
|
|
directive.span,
|
|
directive.crate_lint(),
|
|
);
|
|
directive.vis.set(orig_vis);
|
|
|
|
match path_res {
|
|
PathResult::Module(module) => module,
|
|
PathResult::Indeterminate => return false,
|
|
PathResult::NonModule(..) | PathResult::Failed { .. } => return true,
|
|
}
|
|
};
|
|
|
|
directive.imported_module.set(Some(module));
|
|
let (source, target, source_bindings, target_bindings, type_ns_only) =
|
|
match directive.subclass {
|
|
SingleImport {
|
|
source,
|
|
target,
|
|
ref source_bindings,
|
|
ref target_bindings,
|
|
type_ns_only,
|
|
..
|
|
} => (source, target, source_bindings, target_bindings, type_ns_only),
|
|
GlobImport { .. } => {
|
|
self.resolve_glob_import(directive);
|
|
return true;
|
|
}
|
|
_ => unreachable!(),
|
|
};
|
|
|
|
let mut indeterminate = false;
|
|
self.r.per_ns(|this, ns| {
|
|
if !type_ns_only || ns == TypeNS {
|
|
if let Err(Undetermined) = source_bindings[ns].get() {
|
|
// For better failure detection, pretend that the import will
|
|
// not define any names while resolving its module path.
|
|
let orig_vis = directive.vis.replace(ty::Visibility::Invisible);
|
|
let binding = this.resolve_ident_in_module(
|
|
module,
|
|
source,
|
|
ns,
|
|
&directive.parent_scope,
|
|
false,
|
|
directive.span,
|
|
);
|
|
directive.vis.set(orig_vis);
|
|
|
|
source_bindings[ns].set(binding);
|
|
} else {
|
|
return;
|
|
};
|
|
|
|
let parent = directive.parent_scope.module;
|
|
match source_bindings[ns].get() {
|
|
Err(Undetermined) => indeterminate = true,
|
|
// Don't update the resolution, because it was never added.
|
|
Err(Determined) if target.name == kw::Underscore => {}
|
|
Err(Determined) => {
|
|
let key = this.new_key(target, ns);
|
|
this.update_resolution(parent, key, |_, resolution| {
|
|
resolution.single_imports.remove(&PtrKey(directive));
|
|
});
|
|
}
|
|
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);
|
|
target_bindings[ns].set(Some(imported_binding));
|
|
this.define(parent, target, ns, imported_binding);
|
|
}
|
|
}
|
|
}
|
|
});
|
|
|
|
!indeterminate
|
|
}
|
|
|
|
/// Performs final import resolution, consistency checks and error reporting.
|
|
///
|
|
/// Optionally returns an unresolved import error. This error is buffered and used to
|
|
/// consolidate multiple unresolved import errors into a single diagnostic.
|
|
fn finalize_import(
|
|
&mut self,
|
|
directive: &'b ImportDirective<'b>,
|
|
) -> Option<UnresolvedImportError> {
|
|
let orig_vis = directive.vis.replace(ty::Visibility::Invisible);
|
|
let prev_ambiguity_errors_len = self.r.ambiguity_errors.len();
|
|
let path_res = self.r.resolve_path(
|
|
&directive.module_path,
|
|
None,
|
|
&directive.parent_scope,
|
|
true,
|
|
directive.span,
|
|
directive.crate_lint(),
|
|
);
|
|
let no_ambiguity = self.r.ambiguity_errors.len() == prev_ambiguity_errors_len;
|
|
directive.vis.set(orig_vis);
|
|
if let PathResult::Failed { .. } | PathResult::NonModule(..) = path_res {
|
|
// Consider erroneous imports used to avoid duplicate diagnostics.
|
|
self.r.used_imports.insert((directive.id, TypeNS));
|
|
}
|
|
let module = match path_res {
|
|
PathResult::Module(module) => {
|
|
// Consistency checks, analogous to `finalize_macro_resolutions`.
|
|
if let Some(initial_module) = directive.imported_module.get() {
|
|
if !ModuleOrUniformRoot::same_def(module, initial_module) && no_ambiguity {
|
|
span_bug!(directive.span, "inconsistent resolution for an import");
|
|
}
|
|
} else {
|
|
if self.r.privacy_errors.is_empty() {
|
|
let msg = "cannot determine resolution for the import";
|
|
let msg_note = "import resolution is stuck, try simplifying other imports";
|
|
self.r.session.struct_span_err(directive.span, msg).note(msg_note).emit();
|
|
}
|
|
}
|
|
|
|
module
|
|
}
|
|
PathResult::Failed { is_error_from_last_segment: false, span, label, suggestion } => {
|
|
if no_ambiguity {
|
|
assert!(directive.imported_module.get().is_none());
|
|
self.r
|
|
.report_error(span, ResolutionError::FailedToResolve { label, suggestion });
|
|
}
|
|
return None;
|
|
}
|
|
PathResult::Failed { is_error_from_last_segment: true, span, label, suggestion } => {
|
|
if no_ambiguity {
|
|
assert!(directive.imported_module.get().is_none());
|
|
let err = match self.make_path_suggestion(
|
|
span,
|
|
directive.module_path.clone(),
|
|
&directive.parent_scope,
|
|
) {
|
|
Some((suggestion, note)) => UnresolvedImportError {
|
|
span,
|
|
label: None,
|
|
note,
|
|
suggestion: Some((
|
|
vec![(span, Segment::names_to_string(&suggestion))],
|
|
String::from("a similar path exists"),
|
|
Applicability::MaybeIncorrect,
|
|
)),
|
|
},
|
|
None => UnresolvedImportError {
|
|
span,
|
|
label: Some(label),
|
|
note: Vec::new(),
|
|
suggestion,
|
|
},
|
|
};
|
|
return Some(err);
|
|
}
|
|
return None;
|
|
}
|
|
PathResult::NonModule(path_res) if path_res.base_res() == Res::Err => {
|
|
if no_ambiguity {
|
|
assert!(directive.imported_module.get().is_none());
|
|
}
|
|
// The error was already reported earlier.
|
|
return None;
|
|
}
|
|
PathResult::Indeterminate | PathResult::NonModule(..) => unreachable!(),
|
|
};
|
|
|
|
let (ident, target, source_bindings, target_bindings, type_ns_only) = match directive
|
|
.subclass
|
|
{
|
|
SingleImport {
|
|
source,
|
|
target,
|
|
ref source_bindings,
|
|
ref target_bindings,
|
|
type_ns_only,
|
|
..
|
|
} => (source, target, source_bindings, target_bindings, type_ns_only),
|
|
GlobImport { is_prelude, ref max_vis } => {
|
|
if directive.module_path.len() <= 1 {
|
|
// HACK(eddyb) `lint_if_path_starts_with_module` needs at least
|
|
// 2 segments, so the `resolve_path` above won't trigger it.
|
|
let mut full_path = directive.module_path.clone();
|
|
full_path.push(Segment::from_ident(Ident::invalid()));
|
|
self.r.lint_if_path_starts_with_module(
|
|
directive.crate_lint(),
|
|
&full_path,
|
|
directive.span,
|
|
None,
|
|
);
|
|
}
|
|
|
|
if let ModuleOrUniformRoot::Module(module) = module {
|
|
if module.def_id() == directive.parent_scope.module.def_id() {
|
|
// Importing a module into itself is not allowed.
|
|
return Some(UnresolvedImportError {
|
|
span: directive.span,
|
|
label: Some(String::from("cannot glob-import a module into itself")),
|
|
note: Vec::new(),
|
|
suggestion: None,
|
|
});
|
|
}
|
|
}
|
|
if !is_prelude &&
|
|
max_vis.get() != ty::Visibility::Invisible && // Allow empty globs.
|
|
!max_vis.get().is_at_least(directive.vis.get(), &*self)
|
|
{
|
|
let msg = "glob import doesn't reexport anything because no candidate is public enough";
|
|
self.r.lint_buffer.buffer_lint(
|
|
UNUSED_IMPORTS,
|
|
directive.id,
|
|
directive.span,
|
|
msg,
|
|
);
|
|
}
|
|
return None;
|
|
}
|
|
_ => unreachable!(),
|
|
};
|
|
|
|
let mut all_ns_err = true;
|
|
self.r.per_ns(|this, ns| {
|
|
if !type_ns_only || ns == TypeNS {
|
|
let orig_vis = directive.vis.replace(ty::Visibility::Invisible);
|
|
let orig_blacklisted_binding =
|
|
mem::replace(&mut this.blacklisted_binding, target_bindings[ns].get());
|
|
let orig_last_import_segment = mem::replace(&mut this.last_import_segment, true);
|
|
let binding = this.resolve_ident_in_module(
|
|
module,
|
|
ident,
|
|
ns,
|
|
&directive.parent_scope,
|
|
true,
|
|
directive.span,
|
|
);
|
|
this.last_import_segment = orig_last_import_segment;
|
|
this.blacklisted_binding = orig_blacklisted_binding;
|
|
directive.vis.set(orig_vis);
|
|
|
|
match binding {
|
|
Ok(binding) => {
|
|
// Consistency checks, analogous to `finalize_macro_resolutions`.
|
|
let initial_res = source_bindings[ns].get().map(|initial_binding| {
|
|
all_ns_err = false;
|
|
if let Some(target_binding) = target_bindings[ns].get() {
|
|
// Note that as_str() de-gensyms the Symbol
|
|
if target.name.as_str() == "_"
|
|
&& initial_binding.is_extern_crate()
|
|
&& !initial_binding.is_import()
|
|
{
|
|
this.record_use(
|
|
ident,
|
|
ns,
|
|
target_binding,
|
|
directive.module_path.is_empty(),
|
|
);
|
|
}
|
|
}
|
|
initial_binding.res()
|
|
});
|
|
let res = binding.res();
|
|
if let Ok(initial_res) = initial_res {
|
|
if res != initial_res && this.ambiguity_errors.is_empty() {
|
|
span_bug!(directive.span, "inconsistent resolution for an import");
|
|
}
|
|
} else {
|
|
if res != Res::Err
|
|
&& this.ambiguity_errors.is_empty()
|
|
&& this.privacy_errors.is_empty()
|
|
{
|
|
let msg = "cannot determine resolution for the import";
|
|
let msg_note =
|
|
"import resolution is stuck, try simplifying other imports";
|
|
this.session
|
|
.struct_span_err(directive.span, msg)
|
|
.note(msg_note)
|
|
.emit();
|
|
}
|
|
}
|
|
}
|
|
Err(..) => {
|
|
// FIXME: This assert may fire if public glob is later shadowed by a private
|
|
// single import (see test `issue-55884-2.rs`). In theory single imports should
|
|
// always block globs, even if they are not yet resolved, so that this kind of
|
|
// self-inconsistent resolution never happens.
|
|
// Reenable the assert when the issue is fixed.
|
|
// assert!(result[ns].get().is_err());
|
|
}
|
|
}
|
|
}
|
|
});
|
|
|
|
if all_ns_err {
|
|
let mut all_ns_failed = true;
|
|
self.r.per_ns(|this, ns| {
|
|
if !type_ns_only || ns == TypeNS {
|
|
let binding = this.resolve_ident_in_module(
|
|
module,
|
|
ident,
|
|
ns,
|
|
&directive.parent_scope,
|
|
true,
|
|
directive.span,
|
|
);
|
|
if binding.is_ok() {
|
|
all_ns_failed = false;
|
|
}
|
|
}
|
|
});
|
|
|
|
return if all_ns_failed {
|
|
let resolutions = match module {
|
|
ModuleOrUniformRoot::Module(module) => {
|
|
Some(self.r.resolutions(module).borrow())
|
|
}
|
|
_ => None,
|
|
};
|
|
let resolutions = resolutions.as_ref().into_iter().flat_map(|r| r.iter());
|
|
let names = resolutions.filter_map(|(BindingKey { ident: 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::Res(Res::Err, _) => return None,
|
|
_ => Some(&i.name),
|
|
}
|
|
}
|
|
_ => Some(&i.name),
|
|
}
|
|
}
|
|
NameResolution { ref single_imports, .. } if single_imports.is_empty() => {
|
|
None
|
|
}
|
|
_ => Some(&i.name),
|
|
}
|
|
});
|
|
|
|
let lev_suggestion =
|
|
find_best_match_for_name(names, &ident.as_str(), None).map(|suggestion| {
|
|
(
|
|
vec![(ident.span, suggestion.to_string())],
|
|
String::from("a similar name exists in the module"),
|
|
Applicability::MaybeIncorrect,
|
|
)
|
|
});
|
|
|
|
let (suggestion, note) =
|
|
match self.check_for_module_export_macro(directive, module, ident) {
|
|
Some((suggestion, note)) => (suggestion.or(lev_suggestion), note),
|
|
_ => (lev_suggestion, Vec::new()),
|
|
};
|
|
|
|
let label = match module {
|
|
ModuleOrUniformRoot::Module(module) => {
|
|
let module_str = module_to_string(module);
|
|
if let Some(module_str) = module_str {
|
|
format!("no `{}` in `{}`", ident, module_str)
|
|
} else {
|
|
format!("no `{}` in the root", ident)
|
|
}
|
|
}
|
|
_ => {
|
|
if !ident.is_path_segment_keyword() {
|
|
format!("no `{}` external crate", ident)
|
|
} else {
|
|
// HACK(eddyb) this shows up for `self` & `super`, which
|
|
// should work instead - for now keep the same error message.
|
|
format!("no `{}` in the root", ident)
|
|
}
|
|
}
|
|
};
|
|
|
|
Some(UnresolvedImportError {
|
|
span: directive.span,
|
|
label: Some(label),
|
|
note,
|
|
suggestion,
|
|
})
|
|
} else {
|
|
// `resolve_ident_in_module` reported a privacy error.
|
|
self.r.import_dummy_binding(directive);
|
|
None
|
|
};
|
|
}
|
|
|
|
let mut reexport_error = None;
|
|
let mut any_successful_reexport = false;
|
|
self.r.per_ns(|this, ns| {
|
|
if let Ok(binding) = source_bindings[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 \
|
|
re-exported (error E0365), consider declaring with \
|
|
`pub`",
|
|
ident
|
|
);
|
|
self.r.lint_buffer.buffer_lint(
|
|
PUB_USE_OF_PRIVATE_EXTERN_CRATE,
|
|
directive.id,
|
|
directive.span,
|
|
&msg,
|
|
);
|
|
} else if ns == TypeNS {
|
|
struct_span_err!(
|
|
self.r.session,
|
|
directive.span,
|
|
E0365,
|
|
"`{}` is private, and cannot be re-exported",
|
|
ident
|
|
)
|
|
.span_label(directive.span, format!("re-export of private `{}`", ident))
|
|
.note(&format!("consider declaring type or module `{}` with `pub`", ident))
|
|
.emit();
|
|
} else {
|
|
let msg = format!("`{}` is private, and cannot be re-exported", ident);
|
|
let note_msg =
|
|
format!("consider marking `{}` as `pub` in the imported module", ident,);
|
|
struct_span_err!(self.r.session, directive.span, E0364, "{}", &msg)
|
|
.span_note(directive.span, ¬e_msg)
|
|
.emit();
|
|
}
|
|
}
|
|
|
|
if directive.module_path.len() <= 1 {
|
|
// HACK(eddyb) `lint_if_path_starts_with_module` needs at least
|
|
// 2 segments, so the `resolve_path` above won't trigger it.
|
|
let mut full_path = directive.module_path.clone();
|
|
full_path.push(Segment::from_ident(ident));
|
|
self.r.per_ns(|this, ns| {
|
|
if let Ok(binding) = source_bindings[ns].get() {
|
|
this.lint_if_path_starts_with_module(
|
|
directive.crate_lint(),
|
|
&full_path,
|
|
directive.span,
|
|
Some(binding),
|
|
);
|
|
}
|
|
});
|
|
}
|
|
|
|
// 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.r.per_ns(|this, ns| {
|
|
if let Some(binding) = source_bindings[ns].get().ok() {
|
|
this.import_res_map.entry(directive.id).or_default()[ns] = Some(binding.res());
|
|
}
|
|
});
|
|
|
|
self.check_for_redundant_imports(
|
|
ident,
|
|
directive,
|
|
source_bindings,
|
|
target_bindings,
|
|
target,
|
|
);
|
|
|
|
debug!("(resolving single import) successfully resolved import");
|
|
None
|
|
}
|
|
|
|
fn check_for_redundant_imports(
|
|
&mut self,
|
|
ident: Ident,
|
|
directive: &'b ImportDirective<'b>,
|
|
source_bindings: &PerNS<Cell<Result<&'b NameBinding<'b>, Determinacy>>>,
|
|
target_bindings: &PerNS<Cell<Option<&'b NameBinding<'b>>>>,
|
|
target: Ident,
|
|
) {
|
|
// Skip if the import was produced by a macro.
|
|
if directive.parent_scope.expansion != ExpnId::root() {
|
|
return;
|
|
}
|
|
|
|
// Skip if we are inside a named module (in contrast to an anonymous
|
|
// module defined by a block).
|
|
if let ModuleKind::Def(..) = directive.parent_scope.module.kind {
|
|
return;
|
|
}
|
|
|
|
let mut is_redundant = PerNS { value_ns: None, type_ns: None, macro_ns: None };
|
|
|
|
let mut redundant_span = PerNS { value_ns: None, type_ns: None, macro_ns: None };
|
|
|
|
self.r.per_ns(|this, ns| {
|
|
if let Some(binding) = source_bindings[ns].get().ok() {
|
|
if binding.res() == Res::Err {
|
|
return;
|
|
}
|
|
|
|
let orig_blacklisted_binding =
|
|
mem::replace(&mut this.blacklisted_binding, target_bindings[ns].get());
|
|
|
|
match this.early_resolve_ident_in_lexical_scope(
|
|
target,
|
|
ScopeSet::All(ns, false),
|
|
&directive.parent_scope,
|
|
false,
|
|
false,
|
|
directive.span,
|
|
) {
|
|
Ok(other_binding) => {
|
|
is_redundant[ns] = Some(
|
|
binding.res() == other_binding.res() && !other_binding.is_ambiguity(),
|
|
);
|
|
redundant_span[ns] = Some((other_binding.span, other_binding.is_import()));
|
|
}
|
|
Err(_) => is_redundant[ns] = Some(false),
|
|
}
|
|
|
|
this.blacklisted_binding = orig_blacklisted_binding;
|
|
}
|
|
});
|
|
|
|
if !is_redundant.is_empty() && is_redundant.present_items().all(|is_redundant| is_redundant)
|
|
{
|
|
let mut redundant_spans: Vec<_> = redundant_span.present_items().collect();
|
|
redundant_spans.sort();
|
|
redundant_spans.dedup();
|
|
self.r.lint_buffer.buffer_lint_with_diagnostic(
|
|
UNUSED_IMPORTS,
|
|
directive.id,
|
|
directive.span,
|
|
&format!("the item `{}` is imported redundantly", ident),
|
|
BuiltinLintDiagnostics::RedundantImport(redundant_spans, ident),
|
|
);
|
|
}
|
|
}
|
|
|
|
fn resolve_glob_import(&mut self, directive: &'b ImportDirective<'b>) {
|
|
let module = match directive.imported_module.get().unwrap() {
|
|
ModuleOrUniformRoot::Module(module) => module,
|
|
_ => {
|
|
self.r.session.span_err(directive.span, "cannot glob-import all possible crates");
|
|
return;
|
|
}
|
|
};
|
|
|
|
if module.is_trait() {
|
|
self.r.session.span_err(directive.span, "items in traits are not importable.");
|
|
return;
|
|
} else if module.def_id() == directive.parent_scope.module.def_id() {
|
|
return;
|
|
} else if let GlobImport { is_prelude: true, .. } = directive.subclass {
|
|
self.r.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 = self
|
|
.r
|
|
.resolutions(module)
|
|
.borrow()
|
|
.iter()
|
|
.filter_map(|(key, resolution)| {
|
|
resolution.borrow().binding().map(|binding| (*key, binding))
|
|
})
|
|
.collect::<Vec<_>>();
|
|
for (mut key, binding) in bindings {
|
|
let scope = match key.ident.span.reverse_glob_adjust(module.expansion, directive.span) {
|
|
Some(Some(def)) => self.r.macro_def_scope(def),
|
|
Some(None) => directive.parent_scope.module,
|
|
None => continue,
|
|
};
|
|
if self.r.is_accessible_from(binding.pseudo_vis(), scope) {
|
|
let imported_binding = self.r.import(binding, directive);
|
|
let _ = self.r.try_define(directive.parent_scope.module, key, imported_binding);
|
|
}
|
|
}
|
|
|
|
// Record the destination of this import
|
|
self.r.record_partial_res(directive.id, PartialRes::new(module.res().unwrap()));
|
|
}
|
|
|
|
// Miscellaneous post-processing, including recording re-exports,
|
|
// 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();
|
|
|
|
module.for_each_child(self.r, |this, ident, ns, binding| {
|
|
// Filter away ambiguous imports and anything that has def-site
|
|
// hygiene.
|
|
// FIXME: Implement actual cross-crate hygiene.
|
|
let is_good_import =
|
|
binding.is_import() && !binding.is_ambiguity() && !ident.span.from_expansion();
|
|
if is_good_import || binding.is_macro_def() {
|
|
let res = binding.res();
|
|
if res != Res::Err {
|
|
if let Some(def_id) = res.opt_def_id() {
|
|
if !def_id.is_local() {
|
|
this.cstore().export_macros_untracked(def_id.krate);
|
|
}
|
|
}
|
|
reexports.push(Export { ident, res, span: binding.span, vis: binding.vis });
|
|
}
|
|
}
|
|
|
|
if let NameBindingKind::Import { binding: orig_binding, directive, .. } = binding.kind {
|
|
if ns == TypeNS
|
|
&& orig_binding.is_variant()
|
|
&& !orig_binding.vis.is_at_least(binding.vis, &*this)
|
|
{
|
|
let msg = match directive.subclass {
|
|
ImportDirectiveSubclass::SingleImport { .. } => {
|
|
format!("variant `{}` is private and cannot be re-exported", ident)
|
|
}
|
|
ImportDirectiveSubclass::GlobImport { .. } => {
|
|
let msg = "enum is private and its variants \
|
|
cannot be re-exported"
|
|
.to_owned();
|
|
let error_id = (
|
|
DiagnosticMessageId::ErrorId(0), // no code?!
|
|
Some(binding.span),
|
|
msg.clone(),
|
|
);
|
|
let fresh =
|
|
this.session.one_time_diagnostics.borrow_mut().insert(error_id);
|
|
if !fresh {
|
|
return;
|
|
}
|
|
msg
|
|
}
|
|
ref s @ _ => bug!("unexpected import subclass {:?}", s),
|
|
};
|
|
let mut err = this.session.struct_span_err(binding.span, &msg);
|
|
|
|
let imported_module = match directive.imported_module.get() {
|
|
Some(ModuleOrUniformRoot::Module(module)) => module,
|
|
_ => bug!("module should exist"),
|
|
};
|
|
let parent_module = imported_module.parent.expect("parent should exist");
|
|
let resolutions = this.resolutions(parent_module).borrow();
|
|
let enum_path_segment_index = directive.module_path.len() - 1;
|
|
let enum_ident = directive.module_path[enum_path_segment_index].ident;
|
|
|
|
let key = this.new_key(enum_ident, TypeNS);
|
|
let enum_resolution = resolutions.get(&key).expect("resolution should exist");
|
|
let enum_span =
|
|
enum_resolution.borrow().binding.expect("binding should exist").span;
|
|
let enum_def_span = this.session.source_map().def_span(enum_span);
|
|
let enum_def_snippet = this
|
|
.session
|
|
.source_map()
|
|
.span_to_snippet(enum_def_span)
|
|
.expect("snippet should exist");
|
|
// potentially need to strip extant `crate`/`pub(path)` for suggestion
|
|
let after_vis_index = enum_def_snippet
|
|
.find("enum")
|
|
.expect("`enum` keyword should exist in snippet");
|
|
let suggestion = format!("pub {}", &enum_def_snippet[after_vis_index..]);
|
|
|
|
this.session.diag_span_suggestion_once(
|
|
&mut err,
|
|
DiagnosticMessageId::ErrorId(0),
|
|
enum_def_span,
|
|
"consider making the enum public",
|
|
suggestion,
|
|
);
|
|
err.emit();
|
|
}
|
|
}
|
|
});
|
|
|
|
if reexports.len() > 0 {
|
|
if let Some(def_id) = module.def_id() {
|
|
self.r.export_map.insert(def_id, reexports);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn import_path_to_string(
|
|
names: &[Ident],
|
|
subclass: &ImportDirectiveSubclass<'_>,
|
|
span: Span,
|
|
) -> String {
|
|
let pos = names.iter().position(|p| span == p.span && p.name != kw::PathRoot);
|
|
let global = !names.is_empty() && names[0].name == kw::PathRoot;
|
|
if let Some(pos) = pos {
|
|
let names = if global { &names[1..pos + 1] } else { &names[..pos + 1] };
|
|
names_to_string(&names.iter().map(|ident| ident.name).collect::<Vec<_>>())
|
|
} 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.iter().map(|ident| ident.name).collect::<Vec<_>>()),
|
|
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(),
|
|
}
|
|
}
|