rust/crates/hir_def/src/item_scope.rs

418 lines
14 KiB
Rust

//! Describes items defined or visible (ie, imported) in a certain scope.
//! This is shared between modules and blocks.
use std::collections::hash_map::Entry;
use base_db::CrateId;
use hir_expand::{name::Name, AstId, MacroCallId, MacroDefKind};
use once_cell::sync::Lazy;
use profile::Count;
use rustc_hash::{FxHashMap, FxHashSet};
use smallvec::SmallVec;
use stdx::format_to;
use syntax::ast;
use crate::{
attr::AttrId, db::DefDatabase, per_ns::PerNs, visibility::Visibility, AdtId, BuiltinType,
ConstId, ImplId, LocalModuleId, MacroDefId, ModuleDefId, ModuleId, TraitId,
};
#[derive(Copy, Clone)]
pub(crate) enum ImportType {
Glob,
Named,
}
#[derive(Debug, Default)]
pub struct PerNsGlobImports {
types: FxHashSet<(LocalModuleId, Name)>,
values: FxHashSet<(LocalModuleId, Name)>,
macros: FxHashSet<(LocalModuleId, Name)>,
}
#[derive(Debug, Default, PartialEq, Eq)]
pub struct ItemScope {
_c: Count<Self>,
/// Defs visible in this scope. This includes `declarations`, but also
/// imports.
types: FxHashMap<Name, (ModuleDefId, Visibility)>,
values: FxHashMap<Name, (ModuleDefId, Visibility)>,
macros: FxHashMap<Name, (MacroDefId, Visibility)>,
unresolved: FxHashSet<Name>,
/// The defs declared in this scope. Each def has a single scope where it is
/// declared.
declarations: Vec<ModuleDefId>,
impls: Vec<ImplId>,
unnamed_consts: Vec<ConstId>,
/// Traits imported via `use Trait as _;`.
unnamed_trait_imports: FxHashMap<TraitId, Visibility>,
/// Macros visible in current module in legacy textual scope
///
/// For macros invoked by an unqualified identifier like `bar!()`, `legacy_macros` will be searched in first.
/// If it yields no result, then it turns to module scoped `macros`.
/// It macros with name qualified with a path like `crate::foo::bar!()`, `legacy_macros` will be skipped,
/// and only normal scoped `macros` will be searched in.
///
/// Note that this automatically inherit macros defined textually before the definition of module itself.
///
/// Module scoped macros will be inserted into `items` instead of here.
// FIXME: Macro shadowing in one module is not properly handled. Non-item place macros will
// be all resolved to the last one defined if shadowing happens.
legacy_macros: FxHashMap<Name, MacroDefId>,
attr_macros: FxHashMap<AstId<ast::Item>, MacroCallId>,
derive_macros: FxHashMap<AstId<ast::Item>, SmallVec<[(AttrId, MacroCallId); 1]>>,
}
pub(crate) static BUILTIN_SCOPE: Lazy<FxHashMap<Name, PerNs>> = Lazy::new(|| {
BuiltinType::ALL
.iter()
.map(|(name, ty)| (name.clone(), PerNs::types((*ty).into(), Visibility::Public)))
.collect()
});
/// Shadow mode for builtin type which can be shadowed by module.
#[derive(Debug, Copy, Clone, PartialEq, Eq)]
pub(crate) enum BuiltinShadowMode {
/// Prefer user-defined modules (or other types) over builtins.
Module,
/// Prefer builtins over user-defined modules (but not other types).
Other,
}
/// Legacy macros can only be accessed through special methods like `get_legacy_macros`.
/// Other methods will only resolve values, types and module scoped macros only.
impl ItemScope {
pub fn entries<'a>(&'a self) -> impl Iterator<Item = (&'a Name, PerNs)> + 'a {
// FIXME: shadowing
let keys: FxHashSet<_> = self
.types
.keys()
.chain(self.values.keys())
.chain(self.macros.keys())
.chain(self.unresolved.iter())
.collect();
keys.into_iter().map(move |name| (name, self.get(name)))
}
pub fn declarations(&self) -> impl Iterator<Item = ModuleDefId> + '_ {
self.declarations.iter().copied()
}
pub fn impls(&self) -> impl Iterator<Item = ImplId> + ExactSizeIterator + '_ {
self.impls.iter().copied()
}
pub fn values(
&self,
) -> impl Iterator<Item = (ModuleDefId, Visibility)> + ExactSizeIterator + '_ {
self.values.values().copied()
}
pub fn unnamed_consts(&self) -> impl Iterator<Item = ConstId> + '_ {
self.unnamed_consts.iter().copied()
}
/// Iterate over all module scoped macros
pub(crate) fn macros<'a>(&'a self) -> impl Iterator<Item = (&'a Name, MacroDefId)> + 'a {
self.entries().filter_map(|(name, def)| def.take_macros().map(|macro_| (name, macro_)))
}
/// Iterate over all legacy textual scoped macros visible at the end of the module
pub(crate) fn legacy_macros<'a>(&'a self) -> impl Iterator<Item = (&'a Name, MacroDefId)> + 'a {
self.legacy_macros.iter().map(|(name, def)| (name, *def))
}
/// Get a name from current module scope, legacy macros are not included
pub(crate) fn get(&self, name: &Name) -> PerNs {
PerNs {
types: self.types.get(name).copied(),
values: self.values.get(name).copied(),
macros: self.macros.get(name).copied(),
}
}
/// XXX: this is O(N) rather than O(1), try to not introduce new usages.
pub(crate) fn name_of(&self, item: ItemInNs) -> Option<(&Name, Visibility)> {
for (name, per_ns) in self.entries() {
if let Some(vis) = item.match_with(per_ns) {
return Some((name, vis));
}
}
None
}
pub(crate) fn traits<'a>(&'a self) -> impl Iterator<Item = TraitId> + 'a {
self.types
.values()
.filter_map(|(def, _)| match def {
ModuleDefId::TraitId(t) => Some(*t),
_ => None,
})
.chain(self.unnamed_trait_imports.keys().copied())
}
pub(crate) fn declare(&mut self, def: ModuleDefId) {
self.declarations.push(def)
}
pub(crate) fn get_legacy_macro(&self, name: &Name) -> Option<MacroDefId> {
self.legacy_macros.get(name).copied()
}
pub(crate) fn define_impl(&mut self, imp: ImplId) {
self.impls.push(imp)
}
pub(crate) fn define_unnamed_const(&mut self, konst: ConstId) {
self.unnamed_consts.push(konst);
}
pub(crate) fn define_legacy_macro(&mut self, name: Name, mac: MacroDefId) {
self.legacy_macros.insert(name, mac);
}
pub(crate) fn add_attr_macro_invoc(&mut self, item: AstId<ast::Item>, call: MacroCallId) {
self.attr_macros.insert(item, call);
}
pub(crate) fn attr_macro_invocs(
&self,
) -> impl Iterator<Item = (AstId<ast::Item>, MacroCallId)> + '_ {
self.attr_macros.iter().map(|(k, v)| (*k, *v))
}
pub(crate) fn add_derive_macro_invoc(
&mut self,
item: AstId<ast::Item>,
call: MacroCallId,
attr_id: AttrId,
) {
self.derive_macros.entry(item).or_default().push((attr_id, call));
}
pub(crate) fn derive_macro_invocs(
&self,
) -> impl Iterator<Item = (AstId<ast::Item>, &[(AttrId, MacroCallId)])> + '_ {
self.derive_macros.iter().map(|(k, v)| (*k, v.as_ref()))
}
pub(crate) fn unnamed_trait_vis(&self, tr: TraitId) -> Option<Visibility> {
self.unnamed_trait_imports.get(&tr).copied()
}
pub(crate) fn push_unnamed_trait(&mut self, tr: TraitId, vis: Visibility) {
self.unnamed_trait_imports.insert(tr, vis);
}
pub(crate) fn push_res_with_import(
&mut self,
glob_imports: &mut PerNsGlobImports,
lookup: (LocalModuleId, Name),
def: PerNs,
def_import_type: ImportType,
) -> bool {
let mut changed = false;
macro_rules! check_changed {
(
$changed:ident,
( $this:ident / $def:ident ) . $field:ident,
$glob_imports:ident [ $lookup:ident ],
$def_import_type:ident
) => {{
let existing = $this.$field.entry($lookup.1.clone());
match (existing, $def.$field) {
(Entry::Vacant(entry), Some(_)) => {
match $def_import_type {
ImportType::Glob => {
$glob_imports.$field.insert($lookup.clone());
}
ImportType::Named => {
$glob_imports.$field.remove(&$lookup);
}
}
if let Some(fld) = $def.$field {
entry.insert(fld);
}
$changed = true;
}
(Entry::Occupied(mut entry), Some(_))
if $glob_imports.$field.contains(&$lookup)
&& matches!($def_import_type, ImportType::Named) =>
{
cov_mark::hit!(import_shadowed);
$glob_imports.$field.remove(&$lookup);
if let Some(fld) = $def.$field {
entry.insert(fld);
}
$changed = true;
}
_ => {}
}
}};
}
check_changed!(changed, (self / def).types, glob_imports[lookup], def_import_type);
check_changed!(changed, (self / def).values, glob_imports[lookup], def_import_type);
check_changed!(changed, (self / def).macros, glob_imports[lookup], def_import_type);
if def.is_none() && self.unresolved.insert(lookup.1) {
changed = true;
}
changed
}
pub(crate) fn resolutions<'a>(&'a self) -> impl Iterator<Item = (Option<Name>, PerNs)> + 'a {
self.entries().map(|(name, res)| (Some(name.clone()), res)).chain(
self.unnamed_trait_imports
.iter()
.map(|(tr, vis)| (None, PerNs::types(ModuleDefId::TraitId(*tr), *vis))),
)
}
pub(crate) fn collect_legacy_macros(&self) -> FxHashMap<Name, MacroDefId> {
self.legacy_macros.clone()
}
/// Marks everything that is not a procedural macro as private to `this_module`.
pub(crate) fn censor_non_proc_macros(&mut self, this_module: ModuleId) {
self.types
.values_mut()
.chain(self.values.values_mut())
.map(|(_, v)| v)
.chain(self.unnamed_trait_imports.values_mut())
.for_each(|vis| *vis = Visibility::Module(this_module));
for (mac, vis) in self.macros.values_mut() {
if let MacroDefKind::ProcMacro(..) = mac.kind {
// FIXME: Technically this is insufficient since reexports of proc macros are also
// forbidden. Practically nobody does that.
continue;
}
*vis = Visibility::Module(this_module);
}
}
pub(crate) fn dump(&self, buf: &mut String) {
let mut entries: Vec<_> = self.resolutions().collect();
entries.sort_by_key(|(name, _)| name.clone());
for (name, def) in entries {
format_to!(buf, "{}:", name.map_or("_".to_string(), |name| name.to_string()));
if def.types.is_some() {
buf.push_str(" t");
}
if def.values.is_some() {
buf.push_str(" v");
}
if def.macros.is_some() {
buf.push_str(" m");
}
if def.is_none() {
buf.push_str(" _");
}
buf.push('\n');
}
}
pub(crate) fn shrink_to_fit(&mut self) {
// Exhaustive match to require handling new fields.
let Self {
_c: _,
types,
values,
macros,
unresolved,
declarations: defs,
impls,
unnamed_consts,
unnamed_trait_imports,
legacy_macros,
attr_macros,
derive_macros,
} = self;
types.shrink_to_fit();
values.shrink_to_fit();
macros.shrink_to_fit();
unresolved.shrink_to_fit();
defs.shrink_to_fit();
impls.shrink_to_fit();
unnamed_consts.shrink_to_fit();
unnamed_trait_imports.shrink_to_fit();
legacy_macros.shrink_to_fit();
attr_macros.shrink_to_fit();
derive_macros.shrink_to_fit();
}
}
impl PerNs {
pub(crate) fn from_def(def: ModuleDefId, v: Visibility, has_constructor: bool) -> PerNs {
match def {
ModuleDefId::ModuleId(_) => PerNs::types(def, v),
ModuleDefId::FunctionId(_) => PerNs::values(def, v),
ModuleDefId::AdtId(adt) => match adt {
AdtId::UnionId(_) => PerNs::types(def, v),
AdtId::EnumId(_) => PerNs::types(def, v),
AdtId::StructId(_) => {
if has_constructor {
PerNs::both(def, def, v)
} else {
PerNs::types(def, v)
}
}
},
ModuleDefId::EnumVariantId(_) => PerNs::both(def, def, v),
ModuleDefId::ConstId(_) | ModuleDefId::StaticId(_) => PerNs::values(def, v),
ModuleDefId::TraitId(_) => PerNs::types(def, v),
ModuleDefId::TypeAliasId(_) => PerNs::types(def, v),
ModuleDefId::BuiltinType(_) => PerNs::types(def, v),
}
}
}
#[derive(Clone, Copy, PartialEq, Eq, Debug, Hash)]
pub enum ItemInNs {
Types(ModuleDefId),
Values(ModuleDefId),
Macros(MacroDefId),
}
impl ItemInNs {
fn match_with(self, per_ns: PerNs) -> Option<Visibility> {
match self {
ItemInNs::Types(def) => {
per_ns.types.filter(|(other_def, _)| *other_def == def).map(|(_, vis)| vis)
}
ItemInNs::Values(def) => {
per_ns.values.filter(|(other_def, _)| *other_def == def).map(|(_, vis)| vis)
}
ItemInNs::Macros(def) => {
per_ns.macros.filter(|(other_def, _)| *other_def == def).map(|(_, vis)| vis)
}
}
}
pub fn as_module_def_id(self) -> Option<ModuleDefId> {
match self {
ItemInNs::Types(id) | ItemInNs::Values(id) => Some(id),
ItemInNs::Macros(_) => None,
}
}
/// Returns the crate defining this item (or `None` if `self` is built-in).
pub fn krate(&self, db: &dyn DefDatabase) -> Option<CrateId> {
match self {
ItemInNs::Types(did) | ItemInNs::Values(did) => did.module(db).map(|m| m.krate),
ItemInNs::Macros(id) => Some(id.krate),
}
}
}