1 use rustc_hash::FxHashMap;
4 use ra_syntax::{ast::AttrsOwner, SmolStr};
7 db::{AstDatabase, DefDatabase, HirDatabase},
8 Adt, Crate, Enum, Function, HasSource, ImplBlock, Module, ModuleDef, Static, Struct, Trait,
11 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
12 pub enum LangItemTarget {
22 pub(crate) fn krate(&self, db: &impl HirDatabase) -> Option<Crate> {
24 LangItemTarget::Enum(e) => e.module(db).krate(db),
25 LangItemTarget::Function(f) => f.module(db).krate(db),
26 LangItemTarget::ImplBlock(i) => i.module().krate(db),
27 LangItemTarget::Static(s) => s.module(db).krate(db),
28 LangItemTarget::Struct(s) => s.module(db).krate(db),
29 LangItemTarget::Trait(t) => t.module(db).krate(db),
34 #[derive(Default, Debug, Clone, PartialEq, Eq)]
35 pub struct LangItems {
36 items: FxHashMap<SmolStr, LangItemTarget>,
40 pub fn target<'a>(&'a self, item: &str) -> Option<&'a LangItemTarget> {
44 /// Salsa query. This will look for lang items in a specific crate.
45 pub(crate) fn crate_lang_items_query(
46 db: &(impl DefDatabase + AstDatabase),
49 let mut lang_items = LangItems::default();
51 if let Some(module) = krate.root_module(db) {
52 lang_items.collect_lang_items_recursive(db, module);
58 pub(crate) fn module_lang_items_query(
59 db: &(impl DefDatabase + AstDatabase),
61 ) -> Option<Arc<LangItems>> {
62 let mut lang_items = LangItems::default();
63 lang_items.collect_lang_items(db, module);
64 if lang_items.items.is_empty() {
67 Some(Arc::new(lang_items))
71 /// Salsa query. Look for a lang item, starting from the specified crate and recursively
72 /// traversing its dependencies.
73 pub(crate) fn lang_item_query(
74 db: &impl DefDatabase,
77 ) -> Option<LangItemTarget> {
78 let lang_items = db.crate_lang_items(start_crate);
79 let start_crate_target = lang_items.items.get(&item);
80 if let Some(target) = start_crate_target {
83 for dep in start_crate.dependencies(db) {
84 let dep_crate = dep.krate;
85 let dep_target = db.lang_item(dep_crate, item.clone());
86 if dep_target.is_some() {
94 fn collect_lang_items(&mut self, db: &(impl DefDatabase + AstDatabase), module: Module) {
95 // Look for impl targets
96 for impl_block in module.impl_blocks(db) {
97 let src = impl_block.source(db);
98 if let Some(lang_item_name) = lang_item_name(&src.ast) {
100 .entry(lang_item_name)
101 .or_insert_with(|| LangItemTarget::ImplBlock(impl_block));
105 for def in module.declarations(db) {
107 ModuleDef::Trait(trait_) => {
108 self.collect_lang_item(db, trait_, LangItemTarget::Trait)
110 ModuleDef::Adt(Adt::Enum(e)) => self.collect_lang_item(db, e, LangItemTarget::Enum),
111 ModuleDef::Adt(Adt::Struct(s)) => {
112 self.collect_lang_item(db, s, LangItemTarget::Struct)
114 ModuleDef::Function(f) => self.collect_lang_item(db, f, LangItemTarget::Function),
115 ModuleDef::Static(s) => self.collect_lang_item(db, s, LangItemTarget::Static),
121 fn collect_lang_items_recursive(
123 db: &(impl DefDatabase + AstDatabase),
126 if let Some(module_lang_items) = db.module_lang_items(module) {
127 self.items.extend(module_lang_items.items.iter().map(|(k, v)| (k.clone(), *v)))
130 // Look for lang items in the children
131 for child in module.children(db) {
132 self.collect_lang_items_recursive(db, child);
136 fn collect_lang_item<T, N>(
138 db: &(impl DefDatabase + AstDatabase),
140 constructor: fn(T) -> LangItemTarget,
142 T: Copy + HasSource<Ast = N>,
145 let node = item.source(db).ast;
146 if let Some(lang_item_name) = lang_item_name(&node) {
147 self.items.entry(lang_item_name).or_insert_with(|| constructor(item));
152 fn lang_item_name<T: AttrsOwner>(node: &T) -> Option<SmolStr> {
154 .filter_map(|a| a.as_key_value())
155 .filter(|(key, _)| key == "lang")