4 files changed, 129 insertions, 7 deletions

diff --git a/crates/ra_hir_def/src/attr.rs b/crates/ra_hir_def/src/attr.rs
index 7a9d0fdf4..ce397f6b0 100644
--- a/crates/ra_hir_def/src/attr.rs
+++ b/crates/ra_hir_def/src/attr.rs
@@ -2,7 +2,7 @@
 
 use std::{ops, sync::Arc};
 
-use hir_expand::hygiene::Hygiene;
+use hir_expand::{either::Either, hygiene::Hygiene, AstId};
 use mbe::ast_to_token_tree;
 use ra_cfg::CfgOptions;
 use ra_syntax::{
@@ -11,7 +11,9 @@ use ra_syntax::{
 };
 use tt::Subtree;
 
-use crate::path::Path;
+use crate::{
+    db::DefDatabase2, path::Path, AdtId, AstItemDef, AttrDefId, HasChildSource, HasSource, Lookup,
+};
 
 #[derive(Default, Debug, Clone, PartialEq, Eq)]
 pub struct Attrs {
@@ -30,6 +32,46 @@ impl ops::Deref for Attrs {
 }
 
 impl Attrs {
+    pub(crate) fn attrs_query(db: &impl DefDatabase2, def: AttrDefId) -> Attrs {
+        match def {
+            AttrDefId::ModuleId(module) => {
+                let def_map = db.crate_def_map(module.krate);
+                let src = match def_map[module.module_id].declaration_source(db) {
+                    Some(it) => it,
+                    None => return Attrs::default(),
+                };
+                let hygiene = Hygiene::new(db, src.file_id);
+                Attr::from_attrs_owner(&src.value, &hygiene)
+            }
+            AttrDefId::StructFieldId(it) => {
+                let src = it.parent.child_source(db);
+                match &src.value[it.local_id] {
+                    Either::A(_tuple) => Attrs::default(),
+                    Either::B(record) => {
+                        let hygiene = Hygiene::new(db, src.file_id);
+                        Attr::from_attrs_owner(record, &hygiene)
+                    }
+                }
+            }
+            AttrDefId::AdtId(it) => match it {
+                AdtId::StructId(it) => attrs_from_ast(it.0.lookup_intern(db).ast_id, db),
+                AdtId::EnumId(it) => attrs_from_ast(it.lookup_intern(db).ast_id, db),
+                AdtId::UnionId(it) => attrs_from_ast(it.0.lookup_intern(db).ast_id, db),
+            },
+            AttrDefId::EnumVariantId(it) => {
+                let src = it.parent.child_source(db);
+                let hygiene = Hygiene::new(db, src.file_id);
+                Attr::from_attrs_owner(&src.value[it.local_id], &hygiene)
+            }
+            AttrDefId::StaticId(it) => attrs_from_ast(it.lookup_intern(db).ast_id, db),
+            AttrDefId::ConstId(it) => attrs_from_loc(it.lookup(db), db),
+            AttrDefId::FunctionId(it) => attrs_from_loc(it.lookup(db), db),
+            AttrDefId::TraitId(it) => attrs_from_ast(it.lookup_intern(db).ast_id, db),
+            AttrDefId::TypeAliasId(it) => attrs_from_loc(it.lookup(db), db),
+            AttrDefId::MacroDefId(it) => attrs_from_ast(it.ast_id, db),
+        }
+    }
+
     pub fn has_atom(&self, atom: &str) -> bool {
         self.iter().any(|it| it.is_simple_atom(atom))
     }
@@ -106,3 +148,23 @@ impl Attr {
         cfg_options.is_cfg_enabled(self.as_cfg()?)
     }
 }
+
+fn attrs_from_ast<D, N>(src: AstId<N>, db: &D) -> Attrs
+where
+    N: ast::AttrsOwner,
+    D: DefDatabase2,
+{
+    let hygiene = Hygiene::new(db, src.file_id());
+    Attr::from_attrs_owner(&src.to_node(db), &hygiene)
+}
+
+fn attrs_from_loc<T, D>(node: T, db: &D) -> Attrs
+where
+    T: HasSource,
+    T::Value: ast::AttrsOwner,
+    D: DefDatabase2,
+{
+    let src = node.source(db);
+    let hygiene = Hygiene::new(db, src.file_id);
+    Attr::from_attrs_owner(&src.value, &hygiene)
+}
diff --git a/crates/ra_hir_def/src/db.rs b/crates/ra_hir_def/src/db.rs
index 2c660ab88..e91e741bb 100644
--- a/crates/ra_hir_def/src/db.rs
+++ b/crates/ra_hir_def/src/db.rs
@@ -7,6 +7,7 @@ use ra_syntax::ast;
 
 use crate::{
     adt::{EnumData, StructData},
+    attr::Attrs,
     body::{scope::ExprScopes, Body, BodySourceMap},
     data::{ConstData, FunctionData, ImplData, TraitData, TypeAliasData},
     generics::GenericParams,
@@ -14,7 +15,7 @@ use crate::{
         raw::{ImportSourceMap, RawItems},
         CrateDefMap,
     },
-    ConstId, DefWithBodyId, EnumId, FunctionId, GenericDefId, ImplId, ItemLoc, StaticId,
+    AttrDefId, ConstId, DefWithBodyId, EnumId, FunctionId, GenericDefId, ImplId, ItemLoc, StaticId,
     StructOrUnionId, TraitId, TypeAliasId,
 };
 
@@ -87,4 +88,7 @@ pub trait DefDatabase2: InternDatabase + AstDatabase {
 
     #[salsa::invoke(GenericParams::generic_params_query)]
     fn generic_params(&self, def: GenericDefId) -> Arc<GenericParams>;
+
+    #[salsa::invoke(Attrs::attrs_query)]
+    fn attrs(&self, def: AttrDefId) -> Attrs;
 }
diff --git a/crates/ra_hir_def/src/lib.rs b/crates/ra_hir_def/src/lib.rs
index 2edf743ab..1bcdf9b78 100644
--- a/crates/ra_hir_def/src/lib.rs
+++ b/crates/ra_hir_def/src/lib.rs
@@ -32,7 +32,7 @@ pub mod nameres;
 
 use std::hash::{Hash, Hasher};
 
-use hir_expand::{ast_id_map::FileAstId, db::AstDatabase, AstId, HirFileId, Source};
+use hir_expand::{ast_id_map::FileAstId, db::AstDatabase, AstId, HirFileId, MacroDefId, Source};
 use ra_arena::{impl_arena_id, map::ArenaMap, RawId};
 use ra_db::{salsa, CrateId, FileId};
 use ra_syntax::{ast, AstNode, SyntaxNode};
@@ -280,8 +280,8 @@ pub enum VariantId {
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct StructFieldId {
-    parent: VariantId,
-    local_id: LocalStructFieldId,
+    pub parent: VariantId,
+    pub local_id: LocalStructFieldId,
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
@@ -477,6 +477,33 @@ impl_froms!(
     ConstId
 );
 
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+pub enum AttrDefId {
+    ModuleId(ModuleId),
+    StructFieldId(StructFieldId),
+    AdtId(AdtId),
+    FunctionId(FunctionId),
+    EnumVariantId(EnumVariantId),
+    StaticId(StaticId),
+    ConstId(ConstId),
+    TraitId(TraitId),
+    TypeAliasId(TypeAliasId),
+    MacroDefId(MacroDefId),
+}
+
+impl_froms!(
+    AttrDefId: ModuleId,
+    StructFieldId,
+    AdtId(StructId, EnumId, UnionId),
+    EnumVariantId,
+    StaticId,
+    ConstId,
+    FunctionId,
+    TraitId,
+    TypeAliasId,
+    MacroDefId
+);
+
 trait Intern {
     type ID;
     fn intern(self, db: &impl db::DefDatabase2) -> Self::ID;
diff --git a/crates/ra_hir_def/src/nameres.rs b/crates/ra_hir_def/src/nameres.rs
index c01e020ef..6723465a5 100644
--- a/crates/ra_hir_def/src/nameres.rs
+++ b/crates/ra_hir_def/src/nameres.rs
@@ -58,7 +58,10 @@ mod tests;
 
 use std::sync::Arc;
 
-use hir_expand::{ast_id_map::FileAstId, diagnostics::DiagnosticSink, name::Name, MacroDefId};
+use hir_expand::{
+    ast_id_map::FileAstId, diagnostics::DiagnosticSink, either::Either, name::Name, MacroDefId,
+    Source,
+};
 use once_cell::sync::Lazy;
 use ra_arena::Arena;
 use ra_db::{CrateId, Edition, FileId};
@@ -116,12 +119,15 @@ pub struct ModuleData {
     pub parent: Option<CrateModuleId>,
     pub children: FxHashMap<Name, CrateModuleId>,
     pub scope: ModuleScope,
+
+    //  FIXME: these can't be both null, we need a three-state enum here.
     /// None for root
     pub declaration: Option<AstId<ast::Module>>,
     /// None for inline modules.
     ///
     /// Note that non-inline modules, by definition, live inside non-macro file.
     pub definition: Option<FileId>,
+
     pub impls: Vec<ImplId>,
 }
 
@@ -285,6 +291,29 @@ impl CrateDefMap {
     }
 }
 
+impl ModuleData {
+    /// Returns a node which defines this module. That is, a file or a `mod foo {}` with items.
+    pub fn definition_source(
+        &self,
+        db: &impl DefDatabase2,
+    ) -> Source<Either<ast::SourceFile, ast::Module>> {
+        if let Some(file_id) = self.definition {
+            let sf = db.parse(file_id).tree();
+            return Source::new(file_id.into(), Either::A(sf));
+        }
+        let decl = self.declaration.unwrap();
+        Source::new(decl.file_id(), Either::B(decl.to_node(db)))
+    }
+
+    /// Returns a node which declares this module, either a `mod foo;` or a `mod foo {}`.
+    /// `None` for the crate root.
+    pub fn declaration_source(&self, db: &impl DefDatabase2) -> Option<Source<ast::Module>> {
+        let decl = self.declaration?;
+        let value = decl.to_node(db);
+        Some(Source { file_id: decl.file_id(), value })
+    }
+}
+
 mod diagnostics {
     use hir_expand::diagnostics::DiagnosticSink;
     use ra_db::RelativePathBuf;