| //! A bunch of methods and structures more or less related to resolving macros and |
| //! interface provided by `Resolver` to macro expander. |
| |
| use std::cell::Cell; |
| use std::mem; |
| |
| use rustc_ast::expand::StrippedCfgItem; |
| use rustc_ast::{self as ast, Crate, Inline, ItemKind, ModKind, NodeId, attr}; |
| use rustc_ast_pretty::pprust; |
| use rustc_attr::StabilityLevel; |
| use rustc_data_structures::intern::Interned; |
| use rustc_data_structures::sync::Lrc; |
| use rustc_errors::{Applicability, StashKey}; |
| use rustc_expand::base::{ |
| Annotatable, DeriveResolution, Indeterminate, ResolverExpand, SyntaxExtension, |
| SyntaxExtensionKind, |
| }; |
| use rustc_expand::compile_declarative_macro; |
| use rustc_expand::expand::{ |
| AstFragment, AstFragmentKind, Invocation, InvocationKind, SupportsMacroExpansion, |
| }; |
| use rustc_hir::def::{self, DefKind, Namespace, NonMacroAttrKind}; |
| use rustc_hir::def_id::{CrateNum, DefId, LocalDefId}; |
| use rustc_middle::middle::stability; |
| use rustc_middle::ty::{RegisteredTools, TyCtxt, Visibility}; |
| use rustc_session::lint::BuiltinLintDiag; |
| use rustc_session::lint::builtin::{ |
| LEGACY_DERIVE_HELPERS, OUT_OF_SCOPE_MACRO_CALLS, SOFT_UNSTABLE, |
| UNKNOWN_OR_MALFORMED_DIAGNOSTIC_ATTRIBUTES, UNUSED_MACRO_RULES, UNUSED_MACROS, |
| }; |
| use rustc_session::parse::feature_err; |
| use rustc_span::edit_distance::edit_distance; |
| use rustc_span::edition::Edition; |
| use rustc_span::hygiene::{self, AstPass, ExpnData, ExpnKind, LocalExpnId, MacroKind}; |
| use rustc_span::symbol::{Ident, Symbol, kw, sym}; |
| use rustc_span::{DUMMY_SP, Span}; |
| |
| use crate::Namespace::*; |
| use crate::errors::{ |
| self, AddAsNonDerive, CannotDetermineMacroResolution, CannotFindIdentInThisScope, |
| MacroExpectedFound, RemoveSurroundingDerive, |
| }; |
| use crate::imports::Import; |
| use crate::{ |
| BindingKey, BuiltinMacroState, DeriveData, Determinacy, Finalize, InvocationParent, MacroData, |
| ModuleKind, ModuleOrUniformRoot, NameBinding, NameBindingKind, ParentScope, PathResult, |
| ResolutionError, Resolver, ScopeSet, Segment, ToNameBinding, Used, |
| }; |
| |
| type Res = def::Res<NodeId>; |
| |
| /// Binding produced by a `macro_rules` item. |
| /// Not modularized, can shadow previous `macro_rules` bindings, etc. |
| #[derive(Debug)] |
| pub(crate) struct MacroRulesBinding<'ra> { |
| pub(crate) binding: NameBinding<'ra>, |
| /// `macro_rules` scope into which the `macro_rules` item was planted. |
| pub(crate) parent_macro_rules_scope: MacroRulesScopeRef<'ra>, |
| pub(crate) ident: Ident, |
| } |
| |
| /// The scope introduced by a `macro_rules!` macro. |
| /// This starts at the macro's definition and ends at the end of the macro's parent |
| /// module (named or unnamed), or even further if it escapes with `#[macro_use]`. |
| /// Some macro invocations need to introduce `macro_rules` scopes too because they |
| /// can potentially expand into macro definitions. |
| #[derive(Copy, Clone, Debug)] |
| pub(crate) enum MacroRulesScope<'ra> { |
| /// Empty "root" scope at the crate start containing no names. |
| Empty, |
| /// The scope introduced by a `macro_rules!` macro definition. |
| Binding(&'ra MacroRulesBinding<'ra>), |
| /// The scope introduced by a macro invocation that can potentially |
| /// create a `macro_rules!` macro definition. |
| Invocation(LocalExpnId), |
| } |
| |
| /// `macro_rules!` scopes are always kept by reference and inside a cell. |
| /// The reason is that we update scopes with value `MacroRulesScope::Invocation(invoc_id)` |
| /// in-place after `invoc_id` gets expanded. |
| /// This helps to avoid uncontrollable growth of `macro_rules!` scope chains, |
| /// which usually grow linearly with the number of macro invocations |
| /// in a module (including derives) and hurt performance. |
| pub(crate) type MacroRulesScopeRef<'ra> = Interned<'ra, Cell<MacroRulesScope<'ra>>>; |
| |
| /// Macro namespace is separated into two sub-namespaces, one for bang macros and |
| /// one for attribute-like macros (attributes, derives). |
| /// We ignore resolutions from one sub-namespace when searching names in scope for another. |
| pub(crate) fn sub_namespace_match( |
| candidate: Option<MacroKind>, |
| requirement: Option<MacroKind>, |
| ) -> bool { |
| #[derive(PartialEq)] |
| enum SubNS { |
| Bang, |
| AttrLike, |
| } |
| let sub_ns = |kind| match kind { |
| MacroKind::Bang => SubNS::Bang, |
| MacroKind::Attr | MacroKind::Derive => SubNS::AttrLike, |
| }; |
| let candidate = candidate.map(sub_ns); |
| let requirement = requirement.map(sub_ns); |
| // "No specific sub-namespace" means "matches anything" for both requirements and candidates. |
| candidate.is_none() || requirement.is_none() || candidate == requirement |
| } |
| |
| // We don't want to format a path using pretty-printing, |
| // `format!("{}", path)`, because that tries to insert |
| // line-breaks and is slow. |
| fn fast_print_path(path: &ast::Path) -> Symbol { |
| if let [segment] = path.segments.as_slice() { |
| segment.ident.name |
| } else { |
| let mut path_str = String::with_capacity(64); |
| for (i, segment) in path.segments.iter().enumerate() { |
| if i != 0 { |
| path_str.push_str("::"); |
| } |
| if segment.ident.name != kw::PathRoot { |
| path_str.push_str(segment.ident.as_str()) |
| } |
| } |
| Symbol::intern(&path_str) |
| } |
| } |
| |
| pub(crate) fn registered_tools(tcx: TyCtxt<'_>, (): ()) -> RegisteredTools { |
| let mut registered_tools = RegisteredTools::default(); |
| let (_, pre_configured_attrs) = &*tcx.crate_for_resolver(()).borrow(); |
| for attr in attr::filter_by_name(pre_configured_attrs, sym::register_tool) { |
| for meta_item_inner in attr.meta_item_list().unwrap_or_default() { |
| match meta_item_inner.ident() { |
| Some(ident) => { |
| if let Some(old_ident) = registered_tools.replace(ident) { |
| tcx.dcx().emit_err(errors::ToolWasAlreadyRegistered { |
| span: ident.span, |
| tool: ident, |
| old_ident_span: old_ident.span, |
| }); |
| } |
| } |
| None => { |
| tcx.dcx().emit_err(errors::ToolOnlyAcceptsIdentifiers { |
| span: meta_item_inner.span(), |
| tool: sym::register_tool, |
| }); |
| } |
| } |
| } |
| } |
| // We implicitly add `rustfmt`, `clippy`, `diagnostic`, `miri` and `rust_analyzer` to known |
| // tools, but it's not an error to register them explicitly. |
| let predefined_tools = |
| [sym::clippy, sym::rustfmt, sym::diagnostic, sym::miri, sym::rust_analyzer]; |
| registered_tools.extend(predefined_tools.iter().cloned().map(Ident::with_dummy_span)); |
| registered_tools |
| } |
| |
| // Some feature gates for inner attributes are reported as lints for backward compatibility. |
| fn soft_custom_inner_attributes_gate(path: &ast::Path, invoc: &Invocation) -> bool { |
| match &path.segments[..] { |
| // `#![test]` |
| [seg] if seg.ident.name == sym::test => return true, |
| // `#![rustfmt::skip]` on out-of-line modules |
| [seg1, seg2] if seg1.ident.name == sym::rustfmt && seg2.ident.name == sym::skip => { |
| if let InvocationKind::Attr { item, .. } = &invoc.kind { |
| if let Annotatable::Item(item) = item { |
| if let ItemKind::Mod(_, ModKind::Loaded(_, Inline::No, _)) = item.kind { |
| return true; |
| } |
| } |
| } |
| } |
| _ => {} |
| } |
| false |
| } |
| |
| impl<'ra, 'tcx> ResolverExpand for Resolver<'ra, 'tcx> { |
| fn next_node_id(&mut self) -> NodeId { |
| self.next_node_id() |
| } |
| |
| fn invocation_parent(&self, id: LocalExpnId) -> LocalDefId { |
| self.invocation_parents[&id].parent_def |
| } |
| |
| fn resolve_dollar_crates(&mut self) { |
| hygiene::update_dollar_crate_names(|ctxt| { |
| let ident = Ident::new(kw::DollarCrate, DUMMY_SP.with_ctxt(ctxt)); |
| match self.resolve_crate_root(ident).kind { |
| ModuleKind::Def(.., name) if name != kw::Empty => name, |
| _ => kw::Crate, |
| } |
| }); |
| } |
| |
| fn visit_ast_fragment_with_placeholders( |
| &mut self, |
| expansion: LocalExpnId, |
| fragment: &AstFragment, |
| ) { |
| // Integrate the new AST fragment into all the definition and module structures. |
| // We are inside the `expansion` now, but other parent scope components are still the same. |
| let parent_scope = ParentScope { expansion, ..self.invocation_parent_scopes[&expansion] }; |
| let output_macro_rules_scope = self.build_reduced_graph(fragment, parent_scope); |
| self.output_macro_rules_scopes.insert(expansion, output_macro_rules_scope); |
| |
| parent_scope.module.unexpanded_invocations.borrow_mut().remove(&expansion); |
| if let Some(unexpanded_invocations) = |
| self.impl_unexpanded_invocations.get_mut(&self.invocation_parent(expansion)) |
| { |
| unexpanded_invocations.remove(&expansion); |
| } |
| } |
| |
| fn register_builtin_macro(&mut self, name: Symbol, ext: SyntaxExtensionKind) { |
| if self.builtin_macros.insert(name, BuiltinMacroState::NotYetSeen(ext)).is_some() { |
| self.dcx().bug(format!("built-in macro `{name}` was already registered")); |
| } |
| } |
| |
| // Create a new Expansion with a definition site of the provided module, or |
| // a fake empty `#[no_implicit_prelude]` module if no module is provided. |
| fn expansion_for_ast_pass( |
| &mut self, |
| call_site: Span, |
| pass: AstPass, |
| features: &[Symbol], |
| parent_module_id: Option<NodeId>, |
| ) -> LocalExpnId { |
| let parent_module = |
| parent_module_id.map(|module_id| self.local_def_id(module_id).to_def_id()); |
| let expn_id = LocalExpnId::fresh( |
| ExpnData::allow_unstable( |
| ExpnKind::AstPass(pass), |
| call_site, |
| self.tcx.sess.edition(), |
| features.into(), |
| None, |
| parent_module, |
| ), |
| self.create_stable_hashing_context(), |
| ); |
| |
| let parent_scope = |
| parent_module.map_or(self.empty_module, |def_id| self.expect_module(def_id)); |
| self.ast_transform_scopes.insert(expn_id, parent_scope); |
| |
| expn_id |
| } |
| |
| fn resolve_imports(&mut self) { |
| self.resolve_imports() |
| } |
| |
| fn resolve_macro_invocation( |
| &mut self, |
| invoc: &Invocation, |
| eager_expansion_root: LocalExpnId, |
| force: bool, |
| ) -> Result<Lrc<SyntaxExtension>, Indeterminate> { |
| let invoc_id = invoc.expansion_data.id; |
| let parent_scope = match self.invocation_parent_scopes.get(&invoc_id) { |
| Some(parent_scope) => *parent_scope, |
| None => { |
| // If there's no entry in the table, then we are resolving an eagerly expanded |
| // macro, which should inherit its parent scope from its eager expansion root - |
| // the macro that requested this eager expansion. |
| let parent_scope = *self |
| .invocation_parent_scopes |
| .get(&eager_expansion_root) |
| .expect("non-eager expansion without a parent scope"); |
| self.invocation_parent_scopes.insert(invoc_id, parent_scope); |
| parent_scope |
| } |
| }; |
| |
| let (mut derives, mut inner_attr, mut deleg_impl) = (&[][..], false, None); |
| let (path, kind) = match invoc.kind { |
| InvocationKind::Attr { ref attr, derives: ref attr_derives, .. } => { |
| derives = self.arenas.alloc_ast_paths(attr_derives); |
| inner_attr = attr.style == ast::AttrStyle::Inner; |
| (&attr.get_normal_item().path, MacroKind::Attr) |
| } |
| InvocationKind::Bang { ref mac, .. } => (&mac.path, MacroKind::Bang), |
| InvocationKind::Derive { ref path, .. } => (path, MacroKind::Derive), |
| InvocationKind::GlobDelegation { ref item } => { |
| let ast::AssocItemKind::DelegationMac(deleg) = &item.kind else { unreachable!() }; |
| deleg_impl = Some(self.invocation_parent(invoc_id)); |
| // It is sufficient to consider glob delegation a bang macro for now. |
| (&deleg.prefix, MacroKind::Bang) |
| } |
| }; |
| |
| // Derives are not included when `invocations` are collected, so we have to add them here. |
| let parent_scope = &ParentScope { derives, ..parent_scope }; |
| let supports_macro_expansion = invoc.fragment_kind.supports_macro_expansion(); |
| let node_id = invoc.expansion_data.lint_node_id; |
| // This is a heuristic, but it's good enough for the lint. |
| let looks_like_invoc_in_mod_inert_attr = self |
| .invocation_parents |
| .get(&invoc_id) |
| .or_else(|| self.invocation_parents.get(&eager_expansion_root)) |
| .filter(|&&InvocationParent { parent_def: mod_def_id, in_attr, .. }| { |
| in_attr |
| && invoc.fragment_kind == AstFragmentKind::Expr |
| && self.tcx.def_kind(mod_def_id) == DefKind::Mod |
| }) |
| .map(|&InvocationParent { parent_def: mod_def_id, .. }| mod_def_id); |
| let (ext, res) = self.smart_resolve_macro_path( |
| path, |
| kind, |
| supports_macro_expansion, |
| inner_attr, |
| parent_scope, |
| node_id, |
| force, |
| soft_custom_inner_attributes_gate(path, invoc), |
| deleg_impl, |
| looks_like_invoc_in_mod_inert_attr, |
| )?; |
| |
| let span = invoc.span(); |
| let def_id = if deleg_impl.is_some() { None } else { res.opt_def_id() }; |
| invoc_id.set_expn_data( |
| ext.expn_data( |
| parent_scope.expansion, |
| span, |
| fast_print_path(path), |
| def_id, |
| def_id.map(|def_id| self.macro_def_scope(def_id).nearest_parent_mod()), |
| ), |
| self.create_stable_hashing_context(), |
| ); |
| |
| Ok(ext) |
| } |
| |
| fn record_macro_rule_usage(&mut self, id: NodeId, rule_i: usize) { |
| let did = self.local_def_id(id); |
| self.unused_macro_rules.remove(&(did, rule_i)); |
| } |
| |
| fn check_unused_macros(&mut self) { |
| for (_, &(node_id, ident)) in self.unused_macros.iter() { |
| self.lint_buffer.buffer_lint( |
| UNUSED_MACROS, |
| node_id, |
| ident.span, |
| BuiltinLintDiag::UnusedMacroDefinition(ident.name), |
| ); |
| } |
| for (&(def_id, arm_i), &(ident, rule_span)) in self.unused_macro_rules.iter() { |
| if self.unused_macros.contains_key(&def_id) { |
| // We already lint the entire macro as unused |
| continue; |
| } |
| let node_id = self.def_id_to_node_id[def_id]; |
| self.lint_buffer.buffer_lint( |
| UNUSED_MACRO_RULES, |
| node_id, |
| rule_span, |
| BuiltinLintDiag::MacroRuleNeverUsed(arm_i, ident.name), |
| ); |
| } |
| } |
| |
| fn has_derive_copy(&self, expn_id: LocalExpnId) -> bool { |
| self.containers_deriving_copy.contains(&expn_id) |
| } |
| |
| fn resolve_derives( |
| &mut self, |
| expn_id: LocalExpnId, |
| force: bool, |
| derive_paths: &dyn Fn() -> Vec<DeriveResolution>, |
| ) -> Result<(), Indeterminate> { |
| // Block expansion of the container until we resolve all derives in it. |
| // This is required for two reasons: |
| // - Derive helper attributes are in scope for the item to which the `#[derive]` |
| // is applied, so they have to be produced by the container's expansion rather |
| // than by individual derives. |
| // - Derives in the container need to know whether one of them is a built-in `Copy`. |
| // Temporarily take the data to avoid borrow checker conflicts. |
| let mut derive_data = mem::take(&mut self.derive_data); |
| let entry = derive_data.entry(expn_id).or_insert_with(|| DeriveData { |
| resolutions: derive_paths(), |
| helper_attrs: Vec::new(), |
| has_derive_copy: false, |
| }); |
| let parent_scope = self.invocation_parent_scopes[&expn_id]; |
| for (i, resolution) in entry.resolutions.iter_mut().enumerate() { |
| if resolution.exts.is_none() { |
| resolution.exts = Some( |
| match self.resolve_macro_path( |
| &resolution.path, |
| Some(MacroKind::Derive), |
| &parent_scope, |
| true, |
| force, |
| None, |
| ) { |
| Ok((Some(ext), _)) => { |
| if !ext.helper_attrs.is_empty() { |
| let last_seg = resolution.path.segments.last().unwrap(); |
| let span = last_seg.ident.span.normalize_to_macros_2_0(); |
| entry.helper_attrs.extend( |
| ext.helper_attrs |
| .iter() |
| .map(|name| (i, Ident::new(*name, span))), |
| ); |
| } |
| entry.has_derive_copy |= ext.builtin_name == Some(sym::Copy); |
| ext |
| } |
| Ok(_) | Err(Determinacy::Determined) => self.dummy_ext(MacroKind::Derive), |
| Err(Determinacy::Undetermined) => { |
| assert!(self.derive_data.is_empty()); |
| self.derive_data = derive_data; |
| return Err(Indeterminate); |
| } |
| }, |
| ); |
| } |
| } |
| // Sort helpers in a stable way independent from the derive resolution order. |
| entry.helper_attrs.sort_by_key(|(i, _)| *i); |
| let helper_attrs = entry |
| .helper_attrs |
| .iter() |
| .map(|(_, ident)| { |
| let res = Res::NonMacroAttr(NonMacroAttrKind::DeriveHelper); |
| let binding = (res, Visibility::<DefId>::Public, ident.span, expn_id) |
| .to_name_binding(self.arenas); |
| (*ident, binding) |
| }) |
| .collect(); |
| self.helper_attrs.insert(expn_id, helper_attrs); |
| // Mark this derive as having `Copy` either if it has `Copy` itself or if its parent derive |
| // has `Copy`, to support cases like `#[derive(Clone, Copy)] #[derive(Debug)]`. |
| if entry.has_derive_copy || self.has_derive_copy(parent_scope.expansion) { |
| self.containers_deriving_copy.insert(expn_id); |
| } |
| assert!(self.derive_data.is_empty()); |
| self.derive_data = derive_data; |
| Ok(()) |
| } |
| |
| fn take_derive_resolutions(&mut self, expn_id: LocalExpnId) -> Option<Vec<DeriveResolution>> { |
| self.derive_data.remove(&expn_id).map(|data| data.resolutions) |
| } |
| |
| // The function that implements the resolution logic of `#[cfg_accessible(path)]`. |
| // Returns true if the path can certainly be resolved in one of three namespaces, |
| // returns false if the path certainly cannot be resolved in any of the three namespaces. |
| // Returns `Indeterminate` if we cannot give a certain answer yet. |
| fn cfg_accessible( |
| &mut self, |
| expn_id: LocalExpnId, |
| path: &ast::Path, |
| ) -> Result<bool, Indeterminate> { |
| self.path_accessible(expn_id, path, &[TypeNS, ValueNS, MacroNS]) |
| } |
| |
| fn macro_accessible( |
| &mut self, |
| expn_id: LocalExpnId, |
| path: &ast::Path, |
| ) -> Result<bool, Indeterminate> { |
| self.path_accessible(expn_id, path, &[MacroNS]) |
| } |
| |
| fn get_proc_macro_quoted_span(&self, krate: CrateNum, id: usize) -> Span { |
| self.cstore().get_proc_macro_quoted_span_untracked(krate, id, self.tcx.sess) |
| } |
| |
| fn declare_proc_macro(&mut self, id: NodeId) { |
| self.proc_macros.push(id) |
| } |
| |
| fn append_stripped_cfg_item(&mut self, parent_node: NodeId, name: Ident, cfg: ast::MetaItem) { |
| self.stripped_cfg_items.push(StrippedCfgItem { parent_module: parent_node, name, cfg }); |
| } |
| |
| fn registered_tools(&self) -> &RegisteredTools { |
| self.registered_tools |
| } |
| |
| fn register_glob_delegation(&mut self, invoc_id: LocalExpnId) { |
| self.glob_delegation_invoc_ids.insert(invoc_id); |
| } |
| |
| fn glob_delegation_suffixes( |
| &mut self, |
| trait_def_id: DefId, |
| impl_def_id: LocalDefId, |
| ) -> Result<Vec<(Ident, Option<Ident>)>, Indeterminate> { |
| let target_trait = self.expect_module(trait_def_id); |
| if !target_trait.unexpanded_invocations.borrow().is_empty() { |
| return Err(Indeterminate); |
| } |
| // FIXME: Instead of waiting try generating all trait methods, and pruning |
| // the shadowed ones a bit later, e.g. when all macro expansion completes. |
| // Pros: expansion will be stuck less (but only in exotic cases), the implementation may be |
| // less hacky. |
| // Cons: More code is generated just to be deleted later, deleting already created `DefId`s |
| // may be nontrivial. |
| if let Some(unexpanded_invocations) = self.impl_unexpanded_invocations.get(&impl_def_id) |
| && !unexpanded_invocations.is_empty() |
| { |
| return Err(Indeterminate); |
| } |
| |
| let mut idents = Vec::new(); |
| target_trait.for_each_child(self, |this, ident, ns, _binding| { |
| // FIXME: Adjust hygiene for idents from globs, like for glob imports. |
| if let Some(overriding_keys) = this.impl_binding_keys.get(&impl_def_id) |
| && overriding_keys.contains(&BindingKey::new(ident.normalize_to_macros_2_0(), ns)) |
| { |
| // The name is overridden, do not produce it from the glob delegation. |
| } else { |
| idents.push((ident, None)); |
| } |
| }); |
| Ok(idents) |
| } |
| } |
| |
| impl<'ra, 'tcx> Resolver<'ra, 'tcx> { |
| /// Resolve macro path with error reporting and recovery. |
| /// Uses dummy syntax extensions for unresolved macros or macros with unexpected resolutions |
| /// for better error recovery. |
| fn smart_resolve_macro_path( |
| &mut self, |
| path: &ast::Path, |
| kind: MacroKind, |
| supports_macro_expansion: SupportsMacroExpansion, |
| inner_attr: bool, |
| parent_scope: &ParentScope<'ra>, |
| node_id: NodeId, |
| force: bool, |
| soft_custom_inner_attributes_gate: bool, |
| deleg_impl: Option<LocalDefId>, |
| invoc_in_mod_inert_attr: Option<LocalDefId>, |
| ) -> Result<(Lrc<SyntaxExtension>, Res), Indeterminate> { |
| let (ext, res) = match self.resolve_macro_or_delegation_path( |
| path, |
| Some(kind), |
| parent_scope, |
| true, |
| force, |
| deleg_impl, |
| invoc_in_mod_inert_attr.map(|def_id| (def_id, node_id)), |
| None, |
| ) { |
| Ok((Some(ext), res)) => (ext, res), |
| Ok((None, res)) => (self.dummy_ext(kind), res), |
| Err(Determinacy::Determined) => (self.dummy_ext(kind), Res::Err), |
| Err(Determinacy::Undetermined) => return Err(Indeterminate), |
| }; |
| |
| // Everything below is irrelevant to glob delegation, take a shortcut. |
| if deleg_impl.is_some() { |
| if !matches!(res, Res::Err | Res::Def(DefKind::Trait, _)) { |
| self.dcx().emit_err(MacroExpectedFound { |
| span: path.span, |
| expected: "trait", |
| article: "a", |
| found: res.descr(), |
| macro_path: &pprust::path_to_string(path), |
| remove_surrounding_derive: None, |
| add_as_non_derive: None, |
| }); |
| return Ok((self.dummy_ext(kind), Res::Err)); |
| } |
| |
| return Ok((ext, res)); |
| } |
| |
| // Report errors for the resolved macro. |
| for segment in &path.segments { |
| if let Some(args) = &segment.args { |
| self.dcx().emit_err(errors::GenericArgumentsInMacroPath { span: args.span() }); |
| } |
| if kind == MacroKind::Attr && segment.ident.as_str().starts_with("rustc") { |
| self.dcx().emit_err(errors::AttributesStartingWithRustcAreReserved { |
| span: segment.ident.span, |
| }); |
| } |
| } |
| |
| match res { |
| Res::Def(DefKind::Macro(_), def_id) => { |
| if let Some(def_id) = def_id.as_local() { |
| self.unused_macros.remove(&def_id); |
| if self.proc_macro_stubs.contains(&def_id) { |
| self.dcx().emit_err(errors::ProcMacroSameCrate { |
| span: path.span, |
| is_test: self.tcx.sess.is_test_crate(), |
| }); |
| } |
| } |
| } |
| Res::NonMacroAttr(..) | Res::Err => {} |
| _ => panic!("expected `DefKind::Macro` or `Res::NonMacroAttr`"), |
| }; |
| |
| self.check_stability_and_deprecation(&ext, path, node_id); |
| |
| let unexpected_res = if ext.macro_kind() != kind { |
| Some((kind.article(), kind.descr_expected())) |
| } else if matches!(res, Res::Def(..)) { |
| match supports_macro_expansion { |
| SupportsMacroExpansion::No => Some(("a", "non-macro attribute")), |
| SupportsMacroExpansion::Yes { supports_inner_attrs } => { |
| if inner_attr && !supports_inner_attrs { |
| Some(("a", "non-macro inner attribute")) |
| } else { |
| None |
| } |
| } |
| } |
| } else { |
| None |
| }; |
| if let Some((article, expected)) = unexpected_res { |
| let path_str = pprust::path_to_string(path); |
| |
| let mut err = MacroExpectedFound { |
| span: path.span, |
| expected, |
| article, |
| found: res.descr(), |
| macro_path: &path_str, |
| remove_surrounding_derive: None, |
| add_as_non_derive: None, |
| }; |
| |
| // Suggest moving the macro out of the derive() if the macro isn't Derive |
| if !path.span.from_expansion() |
| && kind == MacroKind::Derive |
| && ext.macro_kind() != MacroKind::Derive |
| { |
| err.remove_surrounding_derive = Some(RemoveSurroundingDerive { span: path.span }); |
| err.add_as_non_derive = Some(AddAsNonDerive { macro_path: &path_str }); |
| } |
| |
| self.dcx().emit_err(err); |
| |
| return Ok((self.dummy_ext(kind), Res::Err)); |
| } |
| |
| // We are trying to avoid reporting this error if other related errors were reported. |
| if res != Res::Err && inner_attr && !self.tcx.features().custom_inner_attributes { |
| let is_macro = match res { |
| Res::Def(..) => true, |
| Res::NonMacroAttr(..) => false, |
| _ => unreachable!(), |
| }; |
| if soft_custom_inner_attributes_gate { |
| self.tcx.sess.psess.buffer_lint( |
| SOFT_UNSTABLE, |
| path.span, |
| node_id, |
| BuiltinLintDiag::InnerAttributeUnstable { is_macro }, |
| ); |
| } else { |
| // FIXME: deduplicate with rustc_lint (`BuiltinLintDiag::InnerAttributeUnstable`) |
| let msg = if is_macro { |
| "inner macro attributes are unstable" |
| } else { |
| "custom inner attributes are unstable" |
| }; |
| feature_err(&self.tcx.sess, sym::custom_inner_attributes, path.span, msg).emit(); |
| } |
| } |
| |
| if res == Res::NonMacroAttr(NonMacroAttrKind::Tool) |
| && let [namespace, attribute, ..] = &*path.segments |
| && namespace.ident.name == sym::diagnostic |
| && !(attribute.ident.name == sym::on_unimplemented |
| || (attribute.ident.name == sym::do_not_recommend |
| && self.tcx.features().do_not_recommend)) |
| { |
| let distance = |
| edit_distance(attribute.ident.name.as_str(), sym::on_unimplemented.as_str(), 5); |
| |
| let typo_name = distance.map(|_| sym::on_unimplemented); |
| |
| self.tcx.sess.psess.buffer_lint( |
| UNKNOWN_OR_MALFORMED_DIAGNOSTIC_ATTRIBUTES, |
| attribute.span(), |
| node_id, |
| BuiltinLintDiag::UnknownDiagnosticAttribute { span: attribute.span(), typo_name }, |
| ); |
| } |
| |
| Ok((ext, res)) |
| } |
| |
| pub(crate) fn resolve_macro_path( |
| &mut self, |
| path: &ast::Path, |
| kind: Option<MacroKind>, |
| parent_scope: &ParentScope<'ra>, |
| trace: bool, |
| force: bool, |
| ignore_import: Option<Import<'ra>>, |
| ) -> Result<(Option<Lrc<SyntaxExtension>>, Res), Determinacy> { |
| self.resolve_macro_or_delegation_path( |
| path, |
| kind, |
| parent_scope, |
| trace, |
| force, |
| None, |
| None, |
| ignore_import, |
| ) |
| } |
| |
| fn resolve_macro_or_delegation_path( |
| &mut self, |
| ast_path: &ast::Path, |
| kind: Option<MacroKind>, |
| parent_scope: &ParentScope<'ra>, |
| trace: bool, |
| force: bool, |
| deleg_impl: Option<LocalDefId>, |
| invoc_in_mod_inert_attr: Option<(LocalDefId, NodeId)>, |
| ignore_import: Option<Import<'ra>>, |
| ) -> Result<(Option<Lrc<SyntaxExtension>>, Res), Determinacy> { |
| let path_span = ast_path.span; |
| let mut path = Segment::from_path(ast_path); |
| |
| // Possibly apply the macro helper hack |
| if deleg_impl.is_none() |
| && kind == Some(MacroKind::Bang) |
| && let [segment] = path.as_slice() |
| && segment.ident.span.ctxt().outer_expn_data().local_inner_macros |
| { |
| let root = Ident::new(kw::DollarCrate, segment.ident.span); |
| path.insert(0, Segment::from_ident(root)); |
| } |
| |
| let res = if deleg_impl.is_some() || path.len() > 1 { |
| let ns = if deleg_impl.is_some() { TypeNS } else { MacroNS }; |
| let res = match self.maybe_resolve_path(&path, Some(ns), parent_scope, ignore_import) { |
| PathResult::NonModule(path_res) if let Some(res) = path_res.full_res() => Ok(res), |
| PathResult::Indeterminate if !force => return Err(Determinacy::Undetermined), |
| PathResult::NonModule(..) |
| | PathResult::Indeterminate |
| | PathResult::Failed { .. } => Err(Determinacy::Determined), |
| PathResult::Module(ModuleOrUniformRoot::Module(module)) => { |
| Ok(module.res().unwrap()) |
| } |
| PathResult::Module(..) => unreachable!(), |
| }; |
| |
| if trace { |
| let kind = kind.expect("macro kind must be specified if tracing is enabled"); |
| self.multi_segment_macro_resolutions.push(( |
| path, |
| path_span, |
| kind, |
| *parent_scope, |
| res.ok(), |
| ns, |
| )); |
| } |
| |
| self.prohibit_imported_non_macro_attrs(None, res.ok(), path_span); |
| res |
| } else { |
| let scope_set = kind.map_or(ScopeSet::All(MacroNS), ScopeSet::Macro); |
| let binding = self.early_resolve_ident_in_lexical_scope( |
| path[0].ident, |
| scope_set, |
| parent_scope, |
| None, |
| force, |
| None, |
| None, |
| ); |
| if let Err(Determinacy::Undetermined) = binding { |
| return Err(Determinacy::Undetermined); |
| } |
| |
| if trace { |
| let kind = kind.expect("macro kind must be specified if tracing is enabled"); |
| self.single_segment_macro_resolutions.push(( |
| path[0].ident, |
| kind, |
| *parent_scope, |
| binding.ok(), |
| )); |
| } |
| |
| let res = binding.map(|binding| binding.res()); |
| self.prohibit_imported_non_macro_attrs(binding.ok(), res.ok(), path_span); |
| self.report_out_of_scope_macro_calls( |
| ast_path, |
| parent_scope, |
| invoc_in_mod_inert_attr, |
| binding.ok(), |
| ); |
| res |
| }; |
| |
| let res = res?; |
| let ext = match deleg_impl { |
| Some(impl_def_id) => match res { |
| def::Res::Def(DefKind::Trait, def_id) => { |
| let edition = self.tcx.sess.edition(); |
| Some(Lrc::new(SyntaxExtension::glob_delegation(def_id, impl_def_id, edition))) |
| } |
| _ => None, |
| }, |
| None => self.get_macro(res).map(|macro_data| macro_data.ext.clone()), |
| }; |
| Ok((ext, res)) |
| } |
| |
| pub(crate) fn finalize_macro_resolutions(&mut self, krate: &Crate) { |
| let check_consistency = |this: &mut Self, |
| path: &[Segment], |
| span, |
| kind: MacroKind, |
| initial_res: Option<Res>, |
| res: Res| { |
| if let Some(initial_res) = initial_res { |
| if res != initial_res { |
| // Make sure compilation does not succeed if preferred macro resolution |
| // has changed after the macro had been expanded. In theory all such |
| // situations should be reported as errors, so this is a bug. |
| this.dcx().span_delayed_bug(span, "inconsistent resolution for a macro"); |
| } |
| } else if this.tcx.dcx().has_errors().is_none() && this.privacy_errors.is_empty() { |
| // It's possible that the macro was unresolved (indeterminate) and silently |
| // expanded into a dummy fragment for recovery during expansion. |
| // Now, post-expansion, the resolution may succeed, but we can't change the |
| // past and need to report an error. |
| // However, non-speculative `resolve_path` can successfully return private items |
| // even if speculative `resolve_path` returned nothing previously, so we skip this |
| // less informative error if no other error is reported elsewhere. |
| |
| let err = this.dcx().create_err(CannotDetermineMacroResolution { |
| span, |
| kind: kind.descr(), |
| path: Segment::names_to_string(path), |
| }); |
| err.stash(span, StashKey::UndeterminedMacroResolution); |
| } |
| }; |
| |
| let macro_resolutions = mem::take(&mut self.multi_segment_macro_resolutions); |
| for (mut path, path_span, kind, parent_scope, initial_res, ns) in macro_resolutions { |
| // FIXME: Path resolution will ICE if segment IDs present. |
| for seg in &mut path { |
| seg.id = None; |
| } |
| match self.resolve_path( |
| &path, |
| Some(ns), |
| &parent_scope, |
| Some(Finalize::new(ast::CRATE_NODE_ID, path_span)), |
| None, |
| None, |
| ) { |
| PathResult::NonModule(path_res) if let Some(res) = path_res.full_res() => { |
| check_consistency(self, &path, path_span, kind, initial_res, res) |
| } |
| // This may be a trait for glob delegation expansions. |
| PathResult::Module(ModuleOrUniformRoot::Module(module)) => check_consistency( |
| self, |
| &path, |
| path_span, |
| kind, |
| initial_res, |
| module.res().unwrap(), |
| ), |
| path_res @ (PathResult::NonModule(..) | PathResult::Failed { .. }) => { |
| let mut suggestion = None; |
| let (span, label, module) = |
| if let PathResult::Failed { span, label, module, .. } = path_res { |
| // try to suggest if it's not a macro, maybe a function |
| if let PathResult::NonModule(partial_res) = |
| self.maybe_resolve_path(&path, Some(ValueNS), &parent_scope, None) |
| && partial_res.unresolved_segments() == 0 |
| { |
| let sm = self.tcx.sess.source_map(); |
| let exclamation_span = sm.next_point(span); |
| suggestion = Some(( |
| vec![(exclamation_span, "".to_string())], |
| format!( |
| "{} is not a macro, but a {}, try to remove `!`", |
| Segment::names_to_string(&path), |
| partial_res.base_res().descr() |
| ), |
| Applicability::MaybeIncorrect, |
| )); |
| } |
| (span, label, module) |
| } else { |
| ( |
| path_span, |
| format!( |
| "partially resolved path in {} {}", |
| kind.article(), |
| kind.descr() |
| ), |
| None, |
| ) |
| }; |
| self.report_error(span, ResolutionError::FailedToResolve { |
| segment: path.last().map(|segment| segment.ident.name), |
| label, |
| suggestion, |
| module, |
| }); |
| } |
| PathResult::Module(..) | PathResult::Indeterminate => unreachable!(), |
| } |
| } |
| |
| let macro_resolutions = mem::take(&mut self.single_segment_macro_resolutions); |
| for (ident, kind, parent_scope, initial_binding) in macro_resolutions { |
| match self.early_resolve_ident_in_lexical_scope( |
| ident, |
| ScopeSet::Macro(kind), |
| &parent_scope, |
| Some(Finalize::new(ast::CRATE_NODE_ID, ident.span)), |
| true, |
| None, |
| None, |
| ) { |
| Ok(binding) => { |
| let initial_res = initial_binding.map(|initial_binding| { |
| self.record_use(ident, initial_binding, Used::Other); |
| initial_binding.res() |
| }); |
| let res = binding.res(); |
| let seg = Segment::from_ident(ident); |
| check_consistency(self, &[seg], ident.span, kind, initial_res, res); |
| if res == Res::NonMacroAttr(NonMacroAttrKind::DeriveHelperCompat) { |
| let node_id = self |
| .invocation_parents |
| .get(&parent_scope.expansion) |
| .map_or(ast::CRATE_NODE_ID, |parent| { |
| self.def_id_to_node_id[parent.parent_def] |
| }); |
| self.lint_buffer.buffer_lint( |
| LEGACY_DERIVE_HELPERS, |
| node_id, |
| ident.span, |
| BuiltinLintDiag::LegacyDeriveHelpers(binding.span), |
| ); |
| } |
| } |
| Err(..) => { |
| let expected = kind.descr_expected(); |
| |
| let mut err = self.dcx().create_err(CannotFindIdentInThisScope { |
| span: ident.span, |
| expected, |
| ident, |
| }); |
| self.unresolved_macro_suggestions(&mut err, kind, &parent_scope, ident, krate); |
| err.emit(); |
| } |
| } |
| } |
| |
| let builtin_attrs = mem::take(&mut self.builtin_attrs); |
| for (ident, parent_scope) in builtin_attrs { |
| let _ = self.early_resolve_ident_in_lexical_scope( |
| ident, |
| ScopeSet::Macro(MacroKind::Attr), |
| &parent_scope, |
| Some(Finalize::new(ast::CRATE_NODE_ID, ident.span)), |
| true, |
| None, |
| None, |
| ); |
| } |
| } |
| |
| fn check_stability_and_deprecation( |
| &mut self, |
| ext: &SyntaxExtension, |
| path: &ast::Path, |
| node_id: NodeId, |
| ) { |
| let span = path.span; |
| if let Some(stability) = &ext.stability { |
| if let StabilityLevel::Unstable { reason, issue, is_soft, implied_by } = stability.level |
| { |
| let feature = stability.feature; |
| |
| let is_allowed = |feature| { |
| self.tcx.features().declared_features.contains(&feature) |
| || span.allows_unstable(feature) |
| }; |
| let allowed_by_implication = implied_by.is_some_and(|feature| is_allowed(feature)); |
| if !is_allowed(feature) && !allowed_by_implication { |
| let lint_buffer = &mut self.lint_buffer; |
| let soft_handler = |lint, span, msg: String| { |
| lint_buffer.buffer_lint( |
| lint, |
| node_id, |
| span, |
| BuiltinLintDiag::UnstableFeature( |
| // FIXME make this translatable |
| msg.into(), |
| ), |
| ) |
| }; |
| stability::report_unstable( |
| self.tcx.sess, |
| feature, |
| reason.to_opt_reason(), |
| issue, |
| None, |
| is_soft, |
| span, |
| soft_handler, |
| ); |
| } |
| } |
| } |
| if let Some(depr) = &ext.deprecation { |
| let path = pprust::path_to_string(path); |
| stability::early_report_macro_deprecation( |
| &mut self.lint_buffer, |
| depr, |
| span, |
| node_id, |
| path, |
| ); |
| } |
| } |
| |
| fn prohibit_imported_non_macro_attrs( |
| &self, |
| binding: Option<NameBinding<'ra>>, |
| res: Option<Res>, |
| span: Span, |
| ) { |
| if let Some(Res::NonMacroAttr(kind)) = res { |
| if kind != NonMacroAttrKind::Tool && binding.map_or(true, |b| b.is_import()) { |
| let binding_span = binding.map(|binding| binding.span); |
| self.dcx().emit_err(errors::CannotUseThroughAnImport { |
| span, |
| article: kind.article(), |
| descr: kind.descr(), |
| binding_span, |
| }); |
| } |
| } |
| } |
| |
| fn report_out_of_scope_macro_calls( |
| &mut self, |
| path: &ast::Path, |
| parent_scope: &ParentScope<'ra>, |
| invoc_in_mod_inert_attr: Option<(LocalDefId, NodeId)>, |
| binding: Option<NameBinding<'ra>>, |
| ) { |
| if let Some((mod_def_id, node_id)) = invoc_in_mod_inert_attr |
| && let Some(binding) = binding |
| // This is a `macro_rules` itself, not some import. |
| && let NameBindingKind::Res(res) = binding.kind |
| && let Res::Def(DefKind::Macro(MacroKind::Bang), def_id) = res |
| // And the `macro_rules` is defined inside the attribute's module, |
| // so it cannot be in scope unless imported. |
| && self.tcx.is_descendant_of(def_id, mod_def_id.to_def_id()) |
| { |
| // Try to resolve our ident ignoring `macro_rules` scopes. |
| // If such resolution is successful and gives the same result |
| // (e.g. if the macro is re-imported), then silence the lint. |
| let no_macro_rules = self.arenas.alloc_macro_rules_scope(MacroRulesScope::Empty); |
| let fallback_binding = self.early_resolve_ident_in_lexical_scope( |
| path.segments[0].ident, |
| ScopeSet::Macro(MacroKind::Bang), |
| &ParentScope { macro_rules: no_macro_rules, ..*parent_scope }, |
| None, |
| false, |
| None, |
| None, |
| ); |
| if fallback_binding.ok().and_then(|b| b.res().opt_def_id()) != Some(def_id) { |
| self.tcx.sess.psess.buffer_lint( |
| OUT_OF_SCOPE_MACRO_CALLS, |
| path.span, |
| node_id, |
| BuiltinLintDiag::OutOfScopeMacroCalls { path: pprust::path_to_string(path) }, |
| ); |
| } |
| } |
| } |
| |
| pub(crate) fn check_reserved_macro_name(&mut self, ident: Ident, res: Res) { |
| // Reserve some names that are not quite covered by the general check |
| // performed on `Resolver::builtin_attrs`. |
| if ident.name == sym::cfg || ident.name == sym::cfg_attr { |
| let macro_kind = self.get_macro(res).map(|macro_data| macro_data.ext.macro_kind()); |
| if macro_kind.is_some() && sub_namespace_match(macro_kind, Some(MacroKind::Attr)) { |
| self.dcx() |
| .emit_err(errors::NameReservedInAttributeNamespace { span: ident.span, ident }); |
| } |
| } |
| } |
| |
| /// Compile the macro into a `SyntaxExtension` and its rule spans. |
| /// |
| /// Possibly replace its expander to a pre-defined one for built-in macros. |
| pub(crate) fn compile_macro(&mut self, item: &ast::Item, edition: Edition) -> MacroData { |
| let (mut ext, mut rule_spans) = |
| compile_declarative_macro(self.tcx.sess, self.tcx.features(), item, edition); |
| |
| if let Some(builtin_name) = ext.builtin_name { |
| // The macro was marked with `#[rustc_builtin_macro]`. |
| if let Some(builtin_macro) = self.builtin_macros.get_mut(&builtin_name) { |
| // The macro is a built-in, replace its expander function |
| // while still taking everything else from the source code. |
| // If we already loaded this builtin macro, give a better error message than 'no such builtin macro'. |
| match mem::replace(builtin_macro, BuiltinMacroState::AlreadySeen(item.span)) { |
| BuiltinMacroState::NotYetSeen(builtin_ext) => { |
| ext.kind = builtin_ext; |
| rule_spans = Vec::new(); |
| } |
| BuiltinMacroState::AlreadySeen(span) => { |
| self.dcx().emit_err(errors::AttemptToDefineBuiltinMacroTwice { |
| span: item.span, |
| note_span: span, |
| }); |
| } |
| } |
| } else { |
| self.dcx().emit_err(errors::CannotFindBuiltinMacroWithName { |
| span: item.span, |
| ident: item.ident, |
| }); |
| } |
| } |
| |
| let ItemKind::MacroDef(def) = &item.kind else { unreachable!() }; |
| MacroData { ext: Lrc::new(ext), rule_spans, macro_rules: def.macro_rules } |
| } |
| |
| fn path_accessible( |
| &mut self, |
| expn_id: LocalExpnId, |
| path: &ast::Path, |
| namespaces: &[Namespace], |
| ) -> Result<bool, Indeterminate> { |
| let span = path.span; |
| let path = &Segment::from_path(path); |
| let parent_scope = self.invocation_parent_scopes[&expn_id]; |
| |
| let mut indeterminate = false; |
| for ns in namespaces { |
| match self.maybe_resolve_path(path, Some(*ns), &parent_scope, None) { |
| PathResult::Module(ModuleOrUniformRoot::Module(_)) => return Ok(true), |
| PathResult::NonModule(partial_res) if partial_res.unresolved_segments() == 0 => { |
| return Ok(true); |
| } |
| PathResult::NonModule(..) | |
| // HACK(Urgau): This shouldn't be necessary |
| PathResult::Failed { is_error_from_last_segment: false, .. } => { |
| self.dcx() |
| .emit_err(errors::CfgAccessibleUnsure { span }); |
| |
| // If we get a partially resolved NonModule in one namespace, we should get the |
| // same result in any other namespaces, so we can return early. |
| return Ok(false); |
| } |
| PathResult::Indeterminate => indeterminate = true, |
| // We can only be sure that a path doesn't exist after having tested all the |
| // possibilities, only at that time we can return false. |
| PathResult::Failed { .. } => {} |
| PathResult::Module(_) => panic!("unexpected path resolution"), |
| } |
| } |
| |
| if indeterminate { |
| return Err(Indeterminate); |
| } |
| |
| Ok(false) |
| } |
| } |
