use ra_db::FileId; use ra_syntax::ast; use rustc_hash::FxHashMap; use test_utils::tested_by; use crate::{ either::Either, ids::{AstItemDef, LocationCtx, MacroCallId, MacroCallLoc, MacroDefId, MacroFileKind}, name::MACRO_RULES, nameres::{ diagnostics::DefDiagnostic, mod_resolution::{resolve_submodule, ParentModule}, raw, CrateDefMap, CrateModuleId, ItemOrMacro, ModuleData, ModuleDef, PerNs, ReachedFixedPoint, Resolution, ResolveMode, }, AstId, Const, DefDatabase, Enum, Function, HirFileId, MacroDef, Module, Name, Path, Static, Struct, Trait, TypeAlias, Union, }; pub(super) fn collect_defs(db: &impl DefDatabase, mut def_map: CrateDefMap) -> CrateDefMap { // populate external prelude for dep in def_map.krate.dependencies(db) { log::debug!("crate dep {:?} -> {:?}", dep.name, dep.krate); if let Some(module) = dep.krate.root_module(db) { def_map.extern_prelude.insert(dep.name.clone(), module.into()); } // look for the prelude if def_map.prelude.is_none() { let map = db.crate_def_map(dep.krate); if map.prelude.is_some() { def_map.prelude = map.prelude; } } } let mut collector = DefCollector { db, def_map, glob_imports: FxHashMap::default(), unresolved_imports: Vec::new(), unexpanded_macros: Vec::new(), global_macro_scope: FxHashMap::default(), macro_stack_monitor: MacroStackMonitor::default(), }; collector.collect(); collector.finish() } #[derive(Default)] struct MacroStackMonitor { counts: FxHashMap, /// Mainly use for test validator: Option bool>>, } impl MacroStackMonitor { fn increase(&mut self, macro_def_id: MacroDefId) { *self.counts.entry(macro_def_id).or_default() += 1; } fn decrease(&mut self, macro_def_id: MacroDefId) { *self.counts.entry(macro_def_id).or_default() -= 1; } fn is_poison(&self, macro_def_id: MacroDefId) -> bool { let cur = *self.counts.get(¯o_def_id).unwrap_or(&0); if let Some(validator) = &self.validator { validator(cur) } else { cur > 100 } } } /// Walks the tree of module recursively struct DefCollector { db: DB, def_map: CrateDefMap, glob_imports: FxHashMap>, unresolved_imports: Vec<(CrateModuleId, raw::ImportId, raw::ImportData)>, unexpanded_macros: Vec<(CrateModuleId, AstId, Path)>, global_macro_scope: FxHashMap, /// Some macro use `$tt:tt which mean we have to handle the macro perfectly /// To prevent stack overflow, we add a deep counter here for prevent that. macro_stack_monitor: MacroStackMonitor, } impl<'a, DB> DefCollector<&'a DB> where DB: DefDatabase, { fn collect(&mut self) { let crate_graph = self.db.crate_graph(); let file_id = crate_graph.crate_root(self.def_map.krate.crate_id()); let raw_items = self.db.raw_items(file_id.into()); let module_id = self.def_map.root; self.def_map.modules[module_id].definition = Some(file_id); ModCollector { def_collector: &mut *self, module_id, file_id: file_id.into(), raw_items: &raw_items, parent_module: None, } .collect(raw_items.items()); // main name resolution fixed-point loop. let mut i = 0; loop { self.db.check_canceled(); match (self.resolve_imports(), self.resolve_macros()) { (ReachedFixedPoint::Yes, ReachedFixedPoint::Yes) => break, _ => i += 1, } if i == 1000 { log::error!("diverging name resolution"); break; } } let unresolved_imports = std::mem::replace(&mut self.unresolved_imports, Vec::new()); // show unresolved imports in completion, etc for (module_id, import, import_data) in unresolved_imports { self.record_resolved_import(module_id, Either::A(PerNs::none()), import, &import_data) } } fn define_macro( &mut self, module_id: CrateModuleId, name: Name, macro_id: MacroDefId, export: bool, ) { // macro-by-example in Rust have completely weird name resolution logic, // unlike anything else in the language. We'd don't fully implement yet, // just give a somewhat precise approximation. // // Specifically, we store a set of visible macros in each module, just // like how we do with usual items. This is wrong, however, because // macros can be shadowed and their scopes are mostly unrelated to // modules. To paper over the second problem, we also maintain // `global_macro_scope` which works when we construct `CrateDefMap`, but // is completely ignored in expressions. // // What we should do is that, in CrateDefMap, we should maintain a // separate tower of macro scopes, with ids. Then, for each item in the // module, we need to store it's macro scope. let def = Either::B(MacroDef { id: macro_id }); // In Rust, `#[macro_export]` macros are unconditionally visible at the // crate root, even if the parent modules is **not** visible. if export { self.update(self.def_map.root, None, &[(name.clone(), def.clone())]); // Exported macros are collected in crate level ready for // glob import with `#[macro_use]`. self.def_map.exported_macros.insert(name.clone(), macro_id); } self.update(module_id, None, &[(name.clone(), def)]); self.global_macro_scope.insert(name, macro_id); } /// Import macros from `#[macro_use] extern crate`. /// /// They are non-scoped, and will only be inserted into mutable `global_macro_scope`. fn import_macros_from_extern_crate(&mut self, import: &raw::ImportData) { log::debug!( "importing macros from extern crate: {:?} ({:?})", import, self.def_map.edition, ); let res = self.def_map.resolve_name_in_extern_prelude( &import .path .as_ident() .expect("extern crate should have been desugared to one-element path"), ); if let Some(ModuleDef::Module(m)) = res.take_types() { tested_by!(macro_rules_from_other_crates_are_visible_with_macro_use); self.import_all_macros_exported(m); } } fn import_all_macros_exported(&mut self, module: Module) { let item_map = self.db.crate_def_map(module.krate); for (name, ¯o_id) in &item_map.exported_macros { self.global_macro_scope.insert(name.clone(), macro_id); } } fn resolve_imports(&mut self) -> ReachedFixedPoint { let mut imports = std::mem::replace(&mut self.unresolved_imports, Vec::new()); let mut resolved = Vec::new(); imports.retain(|(module_id, import, import_data)| { let (def, fp) = self.resolve_import(*module_id, import_data); if fp == ReachedFixedPoint::Yes { resolved.push((*module_id, def, *import, import_data.clone())) } fp == ReachedFixedPoint::No }); self.unresolved_imports = imports; // Resolves imports, filling-in module scopes let result = if resolved.is_empty() { ReachedFixedPoint::Yes } else { ReachedFixedPoint::No }; for (module_id, def, import, import_data) in resolved { self.record_resolved_import(module_id, def, import, &import_data) } result } fn resolve_import( &self, module_id: CrateModuleId, import: &raw::ImportData, ) -> (ItemOrMacro, ReachedFixedPoint) { log::debug!("resolving import: {:?} ({:?})", import, self.def_map.edition); if import.is_extern_crate { let res = self.def_map.resolve_name_in_extern_prelude( &import .path .as_ident() .expect("extern crate should have been desugared to one-element path"), ); (Either::A(res), ReachedFixedPoint::Yes) } else { let res = self.def_map.resolve_path_fp_with_macro( self.db, ResolveMode::Import, module_id, &import.path, ); (res.resolved_def, res.reached_fixedpoint) } } fn record_resolved_import( &mut self, module_id: CrateModuleId, def: ItemOrMacro, import_id: raw::ImportId, import: &raw::ImportData, ) { if import.is_glob { log::debug!("glob import: {:?}", import); match def.a().and_then(|item| item.take_types()) { Some(ModuleDef::Module(m)) => { if import.is_prelude { tested_by!(std_prelude); self.def_map.prelude = Some(m); } else if m.krate != self.def_map.krate { tested_by!(glob_across_crates); // glob import from other crate => we can just import everything once let item_map = self.db.crate_def_map(m.krate); let scope = &item_map[m.module_id].scope; let items = scope .items .iter() .map(|(name, res)| (name.clone(), Either::A(res.clone()))); let macros = scope.macros.iter().map(|(name, res)| (name.clone(), Either::B(*res))); let all = items.chain(macros).collect::>(); self.update(module_id, Some(import_id), &all); } else { // glob import from same crate => we do an initial // import, and then need to propagate any further // additions let scope = &self.def_map[m.module_id].scope; let items = scope .items .iter() .map(|(name, res)| (name.clone(), Either::A(res.clone()))); let macros = scope.macros.iter().map(|(name, res)| (name.clone(), Either::B(*res))); let all = items.chain(macros).collect::>(); self.update(module_id, Some(import_id), &all); // record the glob import in case we add further items self.glob_imports .entry(m.module_id) .or_default() .push((module_id, import_id)); } } Some(ModuleDef::Enum(e)) => { tested_by!(glob_enum); // glob import from enum => just import all the variants let variants = e.variants(self.db); let resolutions = variants .into_iter() .filter_map(|variant| { let res = Resolution { def: PerNs::both(variant.into(), variant.into()), import: Some(import_id), }; let name = variant.name(self.db)?; Some((name, Either::A(res))) }) .collect::>(); self.update(module_id, Some(import_id), &resolutions); } Some(d) => { log::debug!("glob import {:?} from non-module/enum {:?}", import, d); } None => { log::debug!("glob import {:?} didn't resolve as type", import); } } } else { match import.path.segments.last() { Some(last_segment) => { let name = import.alias.clone().unwrap_or_else(|| last_segment.name.clone()); log::debug!("resolved import {:?} ({:?}) to {:?}", name, import, def); // extern crates in the crate root are special-cased to insert entries into the extern prelude: rust-lang/rust#54658 if import.is_extern_crate && module_id == self.def_map.root { if let Some(def) = def.a().and_then(|item| item.take_types()) { self.def_map.extern_prelude.insert(name.clone(), def); } } let resolution = match def { Either::A(item) => { Either::A(Resolution { def: item, import: Some(import_id) }) } Either::B(macro_) => Either::B(macro_), }; self.update(module_id, Some(import_id), &[(name, resolution)]); } None => tested_by!(bogus_paths), } } } fn update( &mut self, module_id: CrateModuleId, import: Option, resolutions: &[(Name, Either)], ) { self.update_recursive(module_id, import, resolutions, 0) } fn update_recursive( &mut self, module_id: CrateModuleId, import: Option, resolutions: &[(Name, Either)], depth: usize, ) { if depth > 100 { // prevent stack overflows (but this shouldn't be possible) panic!("infinite recursion in glob imports!"); } let module_items = &mut self.def_map.modules[module_id].scope; let mut changed = false; for (name, res) in resolutions { match res { // item Either::A(res) => { let existing = module_items.items.entry(name.clone()).or_default(); if existing.def.types.is_none() && res.def.types.is_some() { existing.def.types = res.def.types; existing.import = import.or(res.import); changed = true; } if existing.def.values.is_none() && res.def.values.is_some() { existing.def.values = res.def.values; existing.import = import.or(res.import); changed = true; } if existing.def.is_none() && res.def.is_none() && existing.import.is_none() && res.import.is_some() { existing.import = res.import; } } // macro Either::B(res) => { // Always shadowing module_items.macros.insert(name.clone(), *res); } } } if !changed { return; } let glob_imports = self .glob_imports .get(&module_id) .into_iter() .flat_map(|v| v.iter()) .cloned() .collect::>(); for (glob_importing_module, glob_import) in glob_imports { // We pass the glob import so that the tracked import in those modules is that glob import self.update_recursive(glob_importing_module, Some(glob_import), resolutions, depth + 1); } } fn resolve_macros(&mut self) -> ReachedFixedPoint { let mut macros = std::mem::replace(&mut self.unexpanded_macros, Vec::new()); let mut resolved = Vec::new(); let mut res = ReachedFixedPoint::Yes; macros.retain(|(module_id, ast_id, path)| { let resolved_res = self.def_map.resolve_path_fp_with_macro( self.db, ResolveMode::Other, *module_id, path, ); if let Some(def) = resolved_res.resolved_def.b() { let call_id = MacroCallLoc { def: def.id, ast_id: *ast_id }.id(self.db); resolved.push((*module_id, call_id, def.id)); res = ReachedFixedPoint::No; return false; } if resolved_res.reached_fixedpoint != ReachedFixedPoint::Yes { let crate_name = &path.segments[0].name; // FIXME: // $crate are not handled in resolver right now if crate_name.to_string() == "$crate" { return true; } // FIXME: // Currently `#[cfg(test)]` are ignored and cargo-metadata do not insert // dev-dependencies of dependencies. For example, // if we depend on parking lot, and parking lot has a dev-dependency on lazy_static. // Then `lazy_static` wil not included in `CrateGraph` // We can fix that by proper handling `cfg(test)`. // // So right now we set the fixpoint to No only if its crate is in CrateGraph // See issue #1282 for details let krate = match self.def_map.resolve_name_in_extern_prelude(crate_name).take_types() { Some(ModuleDef::Module(m)) => m.krate(self.db), _ => return true, }; if krate.is_none() { return true; } res = resolved_res.reached_fixedpoint; } true }); self.unexpanded_macros = macros; for (module_id, macro_call_id, macro_def_id) in resolved { self.collect_macro_expansion(module_id, macro_call_id, macro_def_id); } res } fn collect_macro_expansion( &mut self, module_id: CrateModuleId, macro_call_id: MacroCallId, macro_def_id: MacroDefId, ) { if self.def_map.poison_macros.contains(¯o_def_id) { return; } self.macro_stack_monitor.increase(macro_def_id); if !self.macro_stack_monitor.is_poison(macro_def_id) { let file_id: HirFileId = macro_call_id.as_file(MacroFileKind::Items); let raw_items = self.db.raw_items(file_id); ModCollector { def_collector: &mut *self, file_id, module_id, raw_items: &raw_items, parent_module: None, } .collect(raw_items.items()); } else { log::error!("Too deep macro expansion: {:?}", macro_call_id); self.def_map.poison_macros.insert(macro_def_id); } self.macro_stack_monitor.decrease(macro_def_id); } fn finish(self) -> CrateDefMap { self.def_map } } /// Walks a single module, populating defs, imports and macros struct ModCollector<'a, D> { def_collector: D, module_id: CrateModuleId, file_id: HirFileId, raw_items: &'a raw::RawItems, parent_module: Option>, } impl ModCollector<'_, &'_ mut DefCollector<&'_ DB>> where DB: DefDatabase, { fn collect(&mut self, items: &[raw::RawItem]) { // Prelude module is always considered to be `#[macro_use]`. if let Some(prelude_module) = self.def_collector.def_map.prelude { if prelude_module.krate != self.def_collector.def_map.krate { tested_by!(prelude_is_macro_use); self.def_collector.import_all_macros_exported(prelude_module); } } // This should be processed eagerly instead of deferred to resolving. // `#[macro_use] extern crate` is hoisted to imports macros before collecting // any other items. for item in items { if let raw::RawItem::Import(import_id) = *item { let import = self.raw_items[import_id].clone(); if import.is_extern_crate && import.is_macro_use { self.def_collector.import_macros_from_extern_crate(&import); } } } for item in items { match *item { raw::RawItem::Module(m) => self.collect_module(&self.raw_items[m]), raw::RawItem::Import(import_id) => self.def_collector.unresolved_imports.push(( self.module_id, import_id, self.raw_items[import_id].clone(), )), raw::RawItem::Def(def) => self.define_def(&self.raw_items[def]), raw::RawItem::Macro(mac) => self.collect_macro(&self.raw_items[mac]), } } } fn collect_module(&mut self, module: &raw::ModuleData) { match module { // inline module, just recurse raw::ModuleData::Definition { name, items, ast_id, attr_path } => { let module_id = self.push_child_module(name.clone(), ast_id.with_file_id(self.file_id), None); let parent_module = ParentModule { name, attr_path: attr_path.as_ref() }; ModCollector { def_collector: &mut *self.def_collector, module_id, file_id: self.file_id, raw_items: self.raw_items, parent_module: Some(parent_module), } .collect(&*items); } // out of line module, resolve, parse and recurse raw::ModuleData::Declaration { name, ast_id, attr_path } => { let ast_id = ast_id.with_file_id(self.file_id); let is_root = self.def_collector.def_map.modules[self.module_id].parent.is_none(); match resolve_submodule( self.def_collector.db, self.file_id, name, is_root, attr_path.as_ref(), self.parent_module, ) { Ok(file_id) => { let module_id = self.push_child_module(name.clone(), ast_id, Some(file_id)); let raw_items = self.def_collector.db.raw_items(file_id.into()); ModCollector { def_collector: &mut *self.def_collector, module_id, file_id: file_id.into(), raw_items: &raw_items, parent_module: None, } .collect(raw_items.items()) } Err(candidate) => self.def_collector.def_map.diagnostics.push( DefDiagnostic::UnresolvedModule { module: self.module_id, declaration: ast_id, candidate, }, ), }; } } } fn push_child_module( &mut self, name: Name, declaration: AstId, definition: Option, ) -> CrateModuleId { let modules = &mut self.def_collector.def_map.modules; let res = modules.alloc(ModuleData::default()); modules[res].parent = Some(self.module_id); modules[res].declaration = Some(declaration); modules[res].definition = definition; modules[self.module_id].children.insert(name.clone(), res); let resolution = Resolution { def: PerNs::types( Module { krate: self.def_collector.def_map.krate, module_id: res }.into(), ), import: None, }; self.def_collector.update(self.module_id, None, &[(name, Either::A(resolution))]); res } fn define_def(&mut self, def: &raw::DefData) { let module = Module { krate: self.def_collector.def_map.krate, module_id: self.module_id }; let ctx = LocationCtx::new(self.def_collector.db, module, self.file_id); macro_rules! def { ($kind:ident, $ast_id:ident) => { $kind { id: AstItemDef::from_ast_id(ctx, $ast_id) }.into() }; } let name = def.name.clone(); let def: PerNs = match def.kind { raw::DefKind::Function(ast_id) => PerNs::values(def!(Function, ast_id)), raw::DefKind::Struct(ast_id) => { let s = def!(Struct, ast_id); PerNs::both(s, s) } raw::DefKind::Union(ast_id) => { let s = def!(Union, ast_id); PerNs::both(s, s) } raw::DefKind::Enum(ast_id) => PerNs::types(def!(Enum, ast_id)), raw::DefKind::Const(ast_id) => PerNs::values(def!(Const, ast_id)), raw::DefKind::Static(ast_id) => PerNs::values(def!(Static, ast_id)), raw::DefKind::Trait(ast_id) => PerNs::types(def!(Trait, ast_id)), raw::DefKind::TypeAlias(ast_id) => PerNs::types(def!(TypeAlias, ast_id)), }; let resolution = Resolution { def, import: None }; self.def_collector.update(self.module_id, None, &[(name, Either::A(resolution))]) } fn collect_macro(&mut self, mac: &raw::MacroData) { // Case 1: macro rules, define a macro in crate-global mutable scope if is_macro_rules(&mac.path) { if let Some(name) = &mac.name { let macro_id = MacroDefId(mac.ast_id.with_file_id(self.file_id)); self.def_collector.define_macro(self.module_id, name.clone(), macro_id, mac.export) } return; } let ast_id = mac.ast_id.with_file_id(self.file_id); // Case 2: try to expand macro_rules from this crate, triggering // recursive item collection. if let Some(macro_id) = mac.path.as_ident().and_then(|name| self.def_collector.global_macro_scope.get(&name)) { let def = *macro_id; let macro_call_id = MacroCallLoc { def, ast_id }.id(self.def_collector.db); self.def_collector.collect_macro_expansion(self.module_id, macro_call_id, def); return; } // Case 3: path to a macro from another crate, expand during name resolution self.def_collector.unexpanded_macros.push((self.module_id, ast_id, mac.path.clone())) } } fn is_macro_rules(path: &Path) -> bool { path.as_ident() == Some(&MACRO_RULES) } #[cfg(test)] mod tests { use ra_db::SourceDatabase; use super::*; use crate::{mock::MockDatabase, Crate, DefDatabase}; use ra_arena::Arena; use rustc_hash::FxHashSet; fn do_collect_defs( db: &impl DefDatabase, def_map: CrateDefMap, monitor: MacroStackMonitor, ) -> CrateDefMap { let mut collector = DefCollector { db, def_map, glob_imports: FxHashMap::default(), unresolved_imports: Vec::new(), unexpanded_macros: Vec::new(), global_macro_scope: FxHashMap::default(), macro_stack_monitor: monitor, }; collector.collect(); collector.finish() } fn do_limited_resolve(code: &str, limit: u32, poison_limit: u32) -> CrateDefMap { let (db, _source_root, _) = MockDatabase::with_single_file(&code); let crate_id = db.crate_graph().iter().next().unwrap(); let krate = Crate { crate_id }; let def_map = { let edition = krate.edition(&db); let mut modules: Arena = Arena::default(); let root = modules.alloc(ModuleData::default()); CrateDefMap { krate, edition, extern_prelude: FxHashMap::default(), prelude: None, root, modules, poison_macros: FxHashSet::default(), exported_macros: FxHashMap::default(), diagnostics: Vec::new(), } }; let mut monitor = MacroStackMonitor::default(); monitor.validator = Some(Box::new(move |count| { assert!(count < limit); count >= poison_limit })); do_collect_defs(&db, def_map, monitor) } #[test] fn test_macro_expand_limit_width() { do_limited_resolve( r#" macro_rules! foo { ($($ty:ty)*) => { foo!($($ty)*, $($ty)*); } } foo!(KABOOM); "#, 16, 1000, ); } #[test] fn test_macro_expand_poisoned() { let def = do_limited_resolve( r#" macro_rules! foo { ($ty:ty) => { foo!($ty); } } foo!(KABOOM); "#, 100, 16, ); assert_eq!(def.poison_macros.len(), 1); } #[test] fn test_macro_expand_normal() { let def = do_limited_resolve( r#" macro_rules! foo { ($ident:ident) => { struct $ident {} } } foo!(Bar); "#, 16, 16, ); assert_eq!(def.poison_macros.len(), 0); } }