diff options
Diffstat (limited to 'compiler/rustc_resolve/src/imports.rs')
| -rw-r--r-- | compiler/rustc_resolve/src/imports.rs | 220 |
1 files changed, 126 insertions, 94 deletions
diff --git a/compiler/rustc_resolve/src/imports.rs b/compiler/rustc_resolve/src/imports.rs index f2cc50c19..b100a8c17 100644 --- a/compiler/rustc_resolve/src/imports.rs +++ b/compiler/rustc_resolve/src/imports.rs @@ -4,7 +4,10 @@ use crate::diagnostics::{import_candidates, Suggestion}; use crate::Determinacy::{self, *}; use crate::Namespace::*; use crate::{module_to_string, names_to_string, ImportSuggestion}; -use crate::{AmbiguityKind, BindingKey, ModuleKind, ResolutionError, Resolver, Segment}; +use crate::{ + AmbiguityError, AmbiguityErrorMisc, AmbiguityKind, BindingKey, ModuleKind, ResolutionError, + Resolver, Segment, +}; use crate::{Finalize, Module, ModuleOrUniformRoot, ParentScope, PerNS, ScopeSet}; use crate::{NameBinding, NameBindingKind, PathResult}; @@ -44,20 +47,33 @@ pub enum ImportKind<'a> { type_ns_only: bool, /// Did this import result from a nested import? ie. `use foo::{bar, baz};` nested: bool, - /// Additional `NodeId`s allocated to a `ast::UseTree` for automatically generated `use` statement - /// (eg. implicit struct constructors) - additional_ids: (NodeId, NodeId), + /// The ID of the `UseTree` that imported this `Import`. + /// + /// In the case where the `Import` was expanded from a "nested" use tree, + /// this id is the ID of the leaf tree. For example: + /// + /// ```ignore (pacify the merciless tidy) + /// use foo::bar::{a, b} + /// ``` + /// + /// If this is the import for `foo::bar::a`, we would have the ID of the `UseTree` + /// for `a` in this field. + id: NodeId, }, Glob { is_prelude: bool, - max_vis: Cell<Option<ty::Visibility>>, // The visibility of the greatest re-export. - // n.b. `max_vis` is only used in `finalize_import` to check for re-export errors. + // The visibility of the greatest re-export. + // n.b. `max_vis` is only used in `finalize_import` to check for re-export errors. + max_vis: Cell<Option<ty::Visibility>>, + id: NodeId, }, ExternCrate { source: Option<Symbol>, target: Ident, + id: NodeId, }, MacroUse, + MacroExport, } /// Manually implement `Debug` for `ImportKind` because the `source/target_bindings` @@ -71,7 +87,7 @@ impl<'a> std::fmt::Debug for ImportKind<'a> { ref target, ref type_ns_only, ref nested, - ref additional_ids, + ref id, // Ignore the following to avoid an infinite loop while printing. source_bindings: _, target_bindings: _, @@ -81,19 +97,22 @@ impl<'a> std::fmt::Debug for ImportKind<'a> { .field("target", target) .field("type_ns_only", type_ns_only) .field("nested", nested) - .field("additional_ids", additional_ids) + .field("id", id) .finish_non_exhaustive(), - Glob { ref is_prelude, ref max_vis } => f + Glob { ref is_prelude, ref max_vis, ref id } => f .debug_struct("Glob") .field("is_prelude", is_prelude) .field("max_vis", max_vis) + .field("id", id) .finish(), - ExternCrate { ref source, ref target } => f + ExternCrate { ref source, ref target, ref id } => f .debug_struct("ExternCrate") .field("source", source) .field("target", target) + .field("id", id) .finish(), MacroUse => f.debug_struct("MacroUse").finish(), + MacroExport => f.debug_struct("MacroExport").finish(), } } } @@ -103,24 +122,15 @@ impl<'a> std::fmt::Debug for ImportKind<'a> { pub(crate) struct Import<'a> { pub kind: ImportKind<'a>, - /// The ID of the `extern crate`, `UseTree` etc that imported this `Import`. - /// - /// In the case where the `Import` was expanded from a "nested" use tree, - /// this id is the ID of the leaf tree. For example: - /// - /// ```ignore (pacify the merciless tidy) + /// Node ID of the "root" use item -- this is always the same as `ImportKind`'s `id` + /// (if it exists) except in the case of "nested" use trees, in which case + /// it will be the ID of the root use tree. e.g., in the example + /// ```ignore (incomplete code) /// use foo::bar::{a, b} /// ``` - /// - /// If this is the import for `foo::bar::a`, we would have the ID of the `UseTree` - /// for `a` in this field. - pub id: NodeId, - - /// The `id` of the "root" use-kind -- this is always the same as - /// `id` except in the case of "nested" use trees, in which case - /// it will be the `id` of the root use tree. e.g., in the example - /// from `id`, this would be the ID of the `use foo::bar` - /// `UseTree` node. + /// this would be the ID of the `use foo::bar` `UseTree` node. + /// In case of imports without their own node ID it's the closest node that can be used, + /// for example, for reporting lints. pub root_id: NodeId, /// Span of the entire use statement. @@ -161,6 +171,15 @@ impl<'a> Import<'a> { pub(crate) fn expect_vis(&self) -> ty::Visibility { self.vis.get().expect("encountered cleared import visibility") } + + pub(crate) fn id(&self) -> Option<NodeId> { + match self.kind { + ImportKind::Single { id, .. } + | ImportKind::Glob { id, .. } + | ImportKind::ExternCrate { id, .. } => Some(id), + ImportKind::MacroUse | ImportKind::MacroExport => None, + } + } } /// Records information about the resolution of a name in a namespace of a module. @@ -175,7 +194,7 @@ pub(crate) struct NameResolution<'a> { } impl<'a> NameResolution<'a> { - // Returns the binding for the name if it is known or None if it not known. + /// Returns the binding for the name if it is known or None if it not known. pub(crate) fn binding(&self) -> Option<&'a NameBinding<'a>> { self.binding.and_then(|binding| { if !binding.is_glob_import() || self.single_imports.is_empty() { @@ -207,8 +226,8 @@ fn pub_use_of_private_extern_crate_hack(import: &Import<'_>, binding: &NameBindi } impl<'a> Resolver<'a> { - // Given a binding and an import that resolves to it, - // return the corresponding binding defined by the import. + /// Given a binding and an import that resolves to it, + /// return the corresponding binding defined by the import. pub(crate) fn import( &self, binding: &'a NameBinding<'a>, @@ -240,7 +259,7 @@ impl<'a> Resolver<'a> { }) } - // Define the name or return the existing binding if there is a collision. + /// Define the name or return the existing binding if there is a collision. pub(crate) fn try_define( &mut self, module: Module<'a>, @@ -368,7 +387,9 @@ impl<'a> Resolver<'a> { self.record_use(target, dummy_binding, false); } else if import.imported_module.get().is_none() { import.used.set(true); - self.used_imports.insert(import.id); + if let Some(id) = import.id() { + self.used_imports.insert(id); + } } } } @@ -450,7 +471,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> { { // In the case of a new import line, throw a diagnostic message // for the previous line. - self.throw_unresolved_import_error(errors, None); + self.throw_unresolved_import_error(errors); errors = vec![]; } if seen_spans.insert(err.span) { @@ -482,29 +503,21 @@ impl<'a, 'b> ImportResolver<'a, 'b> { } if !errors.is_empty() { - self.throw_unresolved_import_error(errors, None); + self.throw_unresolved_import_error(errors); } } - fn throw_unresolved_import_error( - &self, - errors: Vec<(String, UnresolvedImportError)>, - span: Option<MultiSpan>, - ) { + fn throw_unresolved_import_error(&self, errors: Vec<(String, UnresolvedImportError)>) { + if errors.is_empty() { + return; + } + /// 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 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(", "),); let mut diag = struct_span_err!(self.r.session, span, E0432, "{}", &msg); @@ -718,47 +731,51 @@ impl<'a, 'b> ImportResolver<'a, 'b> { PathResult::Indeterminate => unreachable!(), }; - let (ident, target, source_bindings, target_bindings, type_ns_only) = match import.kind { - ImportKind::Single { - source, - target, - ref source_bindings, - ref target_bindings, - type_ns_only, - .. - } => (source, target, source_bindings, target_bindings, type_ns_only), - ImportKind::Glob { is_prelude, ref max_vis } => { - if import.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 = import.module_path.clone(); - full_path.push(Segment::from_ident(Ident::empty())); - self.r.lint_if_path_starts_with_module(Some(finalize), &full_path, None); - } + let (ident, target, source_bindings, target_bindings, type_ns_only, import_id) = + match import.kind { + ImportKind::Single { + source, + target, + ref source_bindings, + ref target_bindings, + type_ns_only, + id, + .. + } => (source, target, source_bindings, target_bindings, type_ns_only, id), + ImportKind::Glob { is_prelude, ref max_vis, id } => { + if import.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 = import.module_path.clone(); + full_path.push(Segment::from_ident(Ident::empty())); + self.r.lint_if_path_starts_with_module(Some(finalize), &full_path, None); + } - if let ModuleOrUniformRoot::Module(module) = module { - if ptr::eq(module, import.parent_scope.module) { - // Importing a module into itself is not allowed. - return Some(UnresolvedImportError { - span: import.span, - label: Some(String::from("cannot glob-import a module into itself")), - note: None, - suggestion: None, - candidate: None, - }); + if let ModuleOrUniformRoot::Module(module) = module { + if ptr::eq(module, import.parent_scope.module) { + // Importing a module into itself is not allowed. + return Some(UnresolvedImportError { + span: import.span, + label: Some(String::from( + "cannot glob-import a module into itself", + )), + note: None, + suggestion: None, + candidate: None, + }); + } } - } - if !is_prelude + if !is_prelude && let Some(max_vis) = max_vis.get() && !max_vis.is_at_least(import.expect_vis(), &*self.r) { let msg = "glob import doesn't reexport anything because no candidate is public enough"; - self.r.lint_buffer.buffer_lint(UNUSED_IMPORTS, import.id, import.span, msg); + self.r.lint_buffer.buffer_lint(UNUSED_IMPORTS, id, import.span, msg); } - return None; - } - _ => unreachable!(), - }; + return None; + } + _ => unreachable!(), + }; let mut all_ns_err = true; self.r.per_ns(|this, ns| { @@ -777,7 +794,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> { match binding { Ok(binding) => { // Consistency checks, analogous to `finalize_macro_resolutions`. - let initial_res = source_bindings[ns].get().map(|initial_binding| { + let initial_binding = source_bindings[ns].get().map(|initial_binding| { all_ns_err = false; if let Some(target_binding) = target_bindings[ns].get() { if target.name == kw::Underscore @@ -791,12 +808,20 @@ impl<'a, 'b> ImportResolver<'a, 'b> { ); } } - initial_binding.res() + initial_binding }); let res = binding.res(); - if let Ok(initial_res) = initial_res { + if let Ok(initial_binding) = initial_binding { + let initial_res = initial_binding.res(); if res != initial_res && this.ambiguity_errors.is_empty() { - span_bug!(import.span, "inconsistent resolution for an import"); + this.ambiguity_errors.push(AmbiguityError { + kind: AmbiguityKind::Import, + ident, + b1: initial_binding, + b2: binding, + misc1: AmbiguityErrorMisc::None, + misc2: AmbiguityErrorMisc::None, + }); } } else if res != Res::Err && this.ambiguity_errors.is_empty() @@ -858,7 +883,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> { match binding.kind { // Never suggest the name that has binding error // i.e., the name that cannot be previously resolved - NameBindingKind::Res(Res::Err, _) => None, + NameBindingKind::Res(Res::Err) => None, _ => Some(i.name), } } @@ -960,7 +985,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> { ); self.r.lint_buffer.buffer_lint( PUB_USE_OF_PRIVATE_EXTERN_CRATE, - import.id, + import_id, import.span, &msg, ); @@ -989,7 +1014,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> { let mut err = struct_span_err!(self.r.session, import.span, E0364, "{error_msg}"); match binding.kind { - NameBindingKind::Res(Res::Def(DefKind::Macro(_), def_id), _) + NameBindingKind::Res(Res::Def(DefKind::Macro(_), def_id)) // exclude decl_macro if self.r.get_macro_by_def_id(def_id).macro_rules => { @@ -1029,7 +1054,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> { // purposes it's good enough to just favor one over the other. self.r.per_ns(|this, ns| { if let Ok(binding) = source_bindings[ns].get() { - this.import_res_map.entry(import.id).or_default()[ns] = Some(binding.res()); + this.import_res_map.entry(import_id).or_default()[ns] = Some(binding.res()); } }); @@ -1047,6 +1072,9 @@ impl<'a, 'b> ImportResolver<'a, 'b> { target_bindings: &PerNS<Cell<Option<&'b NameBinding<'b>>>>, target: Ident, ) { + // This function is only called for single imports. + let ImportKind::Single { id, .. } = import.kind else { unreachable!() }; + // Skip if the import was produced by a macro. if import.parent_scope.expansion != LocalExpnId::ROOT { return; @@ -1094,7 +1122,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> { redundant_spans.dedup(); self.r.lint_buffer.buffer_lint_with_diagnostic( UNUSED_IMPORTS, - import.id, + id, import.span, &format!("the item `{}` is imported redundantly", ident), BuiltinLintDiagnostics::RedundantImport(redundant_spans, ident), @@ -1103,6 +1131,9 @@ impl<'a, 'b> ImportResolver<'a, 'b> { } fn resolve_glob_import(&mut self, import: &'b Import<'b>) { + // This function is only called for glob imports. + let ImportKind::Glob { id, is_prelude, .. } = import.kind else { unreachable!() }; + let ModuleOrUniformRoot::Module(module) = import.imported_module.get().unwrap() else { self.r.session.span_err(import.span, "cannot glob-import all possible crates"); return; @@ -1113,7 +1144,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> { return; } else if ptr::eq(module, import.parent_scope.module) { return; - } else if let ImportKind::Glob { is_prelude: true, .. } = import.kind { + } else if is_prelude { self.r.prelude = Some(module); return; } @@ -1145,7 +1176,7 @@ impl<'a, 'b> ImportResolver<'a, 'b> { } // Record the destination of this import - self.r.record_partial_res(import.id, PartialRes::new(module.res().unwrap())); + self.r.record_partial_res(id, PartialRes::new(module.res().unwrap())); } // Miscellaneous post-processing, including recording re-exports, @@ -1204,5 +1235,6 @@ fn import_kind_to_string(import_kind: &ImportKind<'_>) -> String { ImportKind::Glob { .. } => "*".to_string(), ImportKind::ExternCrate { .. } => "<extern crate>".to_string(), ImportKind::MacroUse => "#[macro_use]".to_string(), + ImportKind::MacroExport => "#[macro_export]".to_string(), } } |