11 files changed, 118 insertions, 134 deletions

diff --git a/crates/ra_assists/src/test_db.rs b/crates/ra_assists/src/test_db.rs
index 5be7383ed..715270344 100644
--- a/crates/ra_assists/src/test_db.rs
+++ b/crates/ra_assists/src/test_db.rs
@@ -9,7 +9,6 @@ use ra_db::{salsa, CrateId, FileId, FileLoader, FileLoaderDelegate, RelativePath
     ra_db::SourceDatabaseStorage,
     hir::db::InternDatabaseStorage,
     hir::db::AstDatabaseStorage,
-    hir::db::DefDatabaseStorage,
     hir::db::DefDatabase2Storage,
     hir::db::HirDatabaseStorage
 )]
diff --git a/crates/ra_hir/src/code_model.rs b/crates/ra_hir/src/code_model.rs
index 496b4ee8a..4b3ec5457 100644
--- a/crates/ra_hir/src/code_model.rs
+++ b/crates/ra_hir/src/code_model.rs
@@ -1,7 +1,6 @@
 //! FIXME: write short doc here
 
 pub(crate) mod src;
-pub(crate) mod docs;
 
 use std::sync::Arc;
 
@@ -9,11 +8,12 @@ use hir_def::{
     adt::VariantData,
     body::scope::ExprScopes,
     builtin_type::BuiltinType,
+    docs::Documentation,
     nameres::per_ns::PerNs,
     resolver::{HasResolver, TypeNs},
     type_ref::TypeRef,
-    AdtId, ContainerId, CrateModuleId, EnumVariantId, HasModule, ImplId, LocalEnumVariantId,
-    LocalStructFieldId, Lookup, ModuleId, StructFieldId, UnionId,
+    ContainerId, CrateModuleId, HasModule, ImplId, LocalEnumVariantId, LocalStructFieldId, Lookup,
+    ModuleId, UnionId,
 };
 use hir_expand::{
     diagnostics::DiagnosticSink,
@@ -1024,18 +1024,17 @@ pub trait HasAttrs {
 
 impl<T: Into<AttrDef>> HasAttrs for T {
     fn attrs(self, db: &impl DefDatabase) -> Attrs {
-        let def = self.into();
-        match def {
-            AttrDef::Module(it) => db.attrs(it.id.into()),
-            AttrDef::StructField(it) => db.attrs(StructFieldId::from(it).into()),
-            AttrDef::Adt(it) => db.attrs(AdtId::from(it).into()),
-            AttrDef::Function(it) => db.attrs(it.id.into()),
-            AttrDef::EnumVariant(it) => db.attrs(EnumVariantId::from(it).into()),
-            AttrDef::Static(it) => db.attrs(it.id.into()),
-            AttrDef::Const(it) => db.attrs(it.id.into()),
-            AttrDef::Trait(it) => db.attrs(it.id.into()),
-            AttrDef::TypeAlias(it) => db.attrs(it.id.into()),
-            AttrDef::MacroDef(it) => db.attrs(it.id.into()),
-        }
+        let def: AttrDef = self.into();
+        db.attrs(def.into())
+    }
+}
+
+pub trait Docs {
+    fn docs(&self, db: &impl HirDatabase) -> Option<Documentation>;
+}
+impl<T: Into<AttrDef> + Copy> Docs for T {
+    fn docs(&self, db: &impl HirDatabase) -> Option<Documentation> {
+        let def: AttrDef = (*self).into();
+        db.documentation(def.into())
     }
 }
diff --git a/crates/ra_hir/src/code_model/docs.rs b/crates/ra_hir/src/code_model/docs.rs
deleted file mode 100644
index e40efef34..000000000
--- a/crates/ra_hir/src/code_model/docs.rs
+++ /dev/null
@@ -1,97 +0,0 @@
-//! FIXME: write short doc here
-
-use std::sync::Arc;
-
-use ra_syntax::ast;
-
-use crate::{
-    db::{AstDatabase, DefDatabase, HirDatabase},
-    Adt, Const, Enum, EnumVariant, FieldSource, Function, HasSource, MacroDef, Module, Static,
-    Struct, StructField, Trait, TypeAlias, Union,
-};
-
-#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
-pub enum DocDef {
-    Module(Module),
-    StructField(StructField),
-    Adt(Adt),
-    EnumVariant(EnumVariant),
-    Static(Static),
-    Const(Const),
-    Function(Function),
-    Trait(Trait),
-    TypeAlias(TypeAlias),
-    MacroDef(MacroDef),
-}
-
-impl_froms!(
-    DocDef: Module,
-    StructField,
-    Adt(Struct, Enum, Union),
-    EnumVariant,
-    Static,
-    Const,
-    Function,
-    Trait,
-    TypeAlias,
-    MacroDef
-);
-
-/// Holds documentation
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub struct Documentation(Arc<str>);
-
-impl Documentation {
-    fn new(s: &str) -> Documentation {
-        Documentation(s.into())
-    }
-
-    pub fn as_str(&self) -> &str {
-        &*self.0
-    }
-}
-
-impl Into<String> for Documentation {
-    fn into(self) -> String {
-        self.as_str().to_owned()
-    }
-}
-
-pub trait Docs {
-    fn docs(&self, db: &impl HirDatabase) -> Option<Documentation>;
-}
-
-pub(crate) fn docs_from_ast(node: &impl ast::DocCommentsOwner) -> Option<Documentation> {
-    node.doc_comment_text().map(|it| Documentation::new(&it))
-}
-
-pub(crate) fn documentation_query(
-    db: &(impl DefDatabase + AstDatabase),
-    def: DocDef,
-) -> Option<Documentation> {
-    match def {
-        DocDef::Module(it) => docs_from_ast(&it.declaration_source(db)?.value),
-        DocDef::StructField(it) => match it.source(db).value {
-            FieldSource::Named(named) => docs_from_ast(&named),
-            FieldSource::Pos(..) => None,
-        },
-        DocDef::Adt(it) => match it {
-            Adt::Struct(it) => docs_from_ast(&it.source(db).value),
-            Adt::Enum(it) => docs_from_ast(&it.source(db).value),
-            Adt::Union(it) => docs_from_ast(&it.source(db).value),
-        },
-        DocDef::EnumVariant(it) => docs_from_ast(&it.source(db).value),
-        DocDef::Static(it) => docs_from_ast(&it.source(db).value),
-        DocDef::Const(it) => docs_from_ast(&it.source(db).value),
-        DocDef::Function(it) => docs_from_ast(&it.source(db).value),
-        DocDef::Trait(it) => docs_from_ast(&it.source(db).value),
-        DocDef::TypeAlias(it) => docs_from_ast(&it.source(db).value),
-        DocDef::MacroDef(it) => docs_from_ast(&it.source(db).value),
-    }
-}
-
-impl<T: Into<DocDef> + Copy> Docs for T {
-    fn docs(&self, db: &impl HirDatabase) -> Option<Documentation> {
-        db.documentation((*self).into())
-    }
-}
diff --git a/crates/ra_hir/src/db.rs b/crates/ra_hir/src/db.rs
index cae305f98..2dca0f637 100644
--- a/crates/ra_hir/src/db.rs
+++ b/crates/ra_hir/src/db.rs
@@ -5,7 +5,6 @@ use std::sync::Arc;
 use ra_db::salsa;
 
 use crate::{
-    debug::HirDebugDatabase,
     ids,
     ty::{
         method_resolution::CrateImplBlocks,
@@ -18,23 +17,17 @@ use crate::{
 
 pub use hir_def::db::{
     BodyQuery, BodyWithSourceMapQuery, ConstDataQuery, CrateDefMapQuery, CrateLangItemsQuery,
-    DefDatabase2, DefDatabase2Storage, EnumDataQuery, ExprScopesQuery, FunctionDataQuery,
-    GenericParamsQuery, ImplDataQuery, InternDatabase, InternDatabaseStorage, LangItemQuery,
-    ModuleLangItemsQuery, RawItemsQuery, RawItemsWithSourceMapQuery, StaticDataQuery,
-    StructDataQuery, TraitDataQuery, TypeAliasDataQuery,
+    DefDatabase2, DefDatabase2Storage, DocumentationQuery, EnumDataQuery, ExprScopesQuery,
+    FunctionDataQuery, GenericParamsQuery, ImplDataQuery, InternDatabase, InternDatabaseStorage,
+    LangItemQuery, ModuleLangItemsQuery, RawItemsQuery, RawItemsWithSourceMapQuery,
+    StaticDataQuery, StructDataQuery, TraitDataQuery, TypeAliasDataQuery,
 };
 pub use hir_expand::db::{
     AstDatabase, AstDatabaseStorage, AstIdMapQuery, MacroArgQuery, MacroDefQuery, MacroExpandQuery,
     ParseMacroQuery,
 };
 
-// This database uses `AstDatabase` internally,
-#[salsa::query_group(DefDatabaseStorage)]
-#[salsa::requires(AstDatabase)]
-pub trait DefDatabase: HirDebugDatabase + DefDatabase2 {
-    #[salsa::invoke(crate::code_model::docs::documentation_query)]
-    fn documentation(&self, def: crate::DocDef) -> Option<crate::Documentation>;
-}
+pub use DefDatabase2 as DefDatabase;
 
 #[salsa::query_group(HirDatabaseStorage)]
 #[salsa::requires(salsa::Database)]
diff --git a/crates/ra_hir/src/from_id.rs b/crates/ra_hir/src/from_id.rs
index 5d7af00ab..529ac8251 100644
--- a/crates/ra_hir/src/from_id.rs
+++ b/crates/ra_hir/src/from_id.rs
@@ -4,14 +4,14 @@
 //! are splitting the hir.
 
 use hir_def::{
-    AdtId, AssocItemId, ConstId, DefWithBodyId, EnumId, EnumVariantId, FunctionId, GenericDefId,
-    ModuleDefId, StaticId, StructFieldId, StructId, TypeAliasId, UnionId, VariantId,
+    AdtId, AssocItemId, AttrDefId, ConstId, DefWithBodyId, EnumId, EnumVariantId, FunctionId,
+    GenericDefId, ModuleDefId, StaticId, StructFieldId, StructId, TypeAliasId, UnionId, VariantId,
 };
 
 use crate::{
     ty::{CallableDef, TypableDef},
-    Adt, AssocItem, Const, Crate, DefWithBody, EnumVariant, Function, GenericDef, ModuleDef,
-    Static, StructField, TypeAlias, VariantDef,
+    Adt, AssocItem, AttrDef, Const, Crate, DefWithBody, EnumVariant, Function, GenericDef,
+    ModuleDef, Static, StructField, TypeAlias, VariantDef,
 };
 
 impl From<ra_db::CrateId> for Crate {
@@ -240,3 +240,20 @@ impl From<StructField> for StructFieldId {
         StructFieldId { parent: def.parent.into(), local_id: def.id }
     }
 }
+
+impl From<AttrDef> for AttrDefId {
+    fn from(def: AttrDef) -> Self {
+        match def {
+            AttrDef::Module(it) => AttrDefId::ModuleId(it.id),
+            AttrDef::StructField(it) => AttrDefId::StructFieldId(it.into()),
+            AttrDef::Adt(it) => AttrDefId::AdtId(it.into()),
+            AttrDef::Function(it) => AttrDefId::FunctionId(it.id),
+            AttrDef::EnumVariant(it) => AttrDefId::EnumVariantId(it.into()),
+            AttrDef::Static(it) => AttrDefId::StaticId(it.id),
+            AttrDef::Const(it) => AttrDefId::ConstId(it.id),
+            AttrDef::Trait(it) => AttrDefId::TraitId(it.id),
+            AttrDef::TypeAlias(it) => AttrDefId::TypeAliasId(it.id),
+            AttrDef::MacroDef(it) => AttrDefId::MacroDefId(it.id),
+        }
+    }
+}
diff --git a/crates/ra_hir/src/lib.rs b/crates/ra_hir/src/lib.rs
index 22da05a97..868df5b6b 100644
--- a/crates/ra_hir/src/lib.rs
+++ b/crates/ra_hir/src/lib.rs
@@ -50,9 +50,8 @@ mod marks;
 
 pub use crate::{
     code_model::{
-        docs::{DocDef, Docs, Documentation},
         src::{HasBodySource, HasSource},
-        Adt, AssocItem, AttrDef, Const, Container, Crate, CrateDependency, DefWithBody, Enum,
+        Adt, AssocItem, AttrDef, Const, Container, Crate, CrateDependency, DefWithBody, Docs, Enum,
         EnumVariant, FieldSource, Function, GenericDef, GenericParam, HasAttrs, HasBody, ImplBlock,
         Local, MacroDef, Module, ModuleDef, ModuleSource, ScopeDef, Static, Struct, StructField,
         Trait, TypeAlias, Union, VariantDef,
@@ -70,6 +69,7 @@ pub use crate::{
 
 pub use hir_def::{
     builtin_type::BuiltinType,
+    docs::Documentation,
     nameres::{per_ns::PerNs, raw::ImportId},
     path::{Path, PathKind},
     type_ref::Mutability,
diff --git a/crates/ra_hir/src/test_db.rs b/crates/ra_hir/src/test_db.rs
index 1caa2e875..c369a80d4 100644
--- a/crates/ra_hir/src/test_db.rs
+++ b/crates/ra_hir/src/test_db.rs
@@ -14,7 +14,6 @@ use crate::{db, debug::HirDebugHelper};
     ra_db::SourceDatabaseStorage,
     db::InternDatabaseStorage,
     db::AstDatabaseStorage,
-    db::DefDatabaseStorage,
     db::DefDatabase2Storage,
     db::HirDatabaseStorage
 )]
diff --git a/crates/ra_hir_def/src/db.rs b/crates/ra_hir_def/src/db.rs
index e87bd525a..1481868d0 100644
--- a/crates/ra_hir_def/src/db.rs
+++ b/crates/ra_hir_def/src/db.rs
@@ -10,6 +10,7 @@ use crate::{
     attr::Attrs,
     body::{scope::ExprScopes, Body, BodySourceMap},
     data::{ConstData, FunctionData, ImplData, TraitData, TypeAliasData},
+    docs::Documentation,
     generics::GenericParams,
     lang_item::{LangItemTarget, LangItems},
     nameres::{
@@ -101,4 +102,9 @@ pub trait DefDatabase2: InternDatabase + AstDatabase {
 
     #[salsa::invoke(LangItems::lang_item_query)]
     fn lang_item(&self, start_crate: CrateId, item: SmolStr) -> Option<LangItemTarget>;
+
+    // FIXME(https://github.com/rust-analyzer/rust-analyzer/issues/2148#issuecomment-550519102)
+    // Remove this query completely, in favor of `Attrs::docs` method
+    #[salsa::invoke(Documentation::documentation_query)]
+    fn documentation(&self, def: AttrDefId) -> Option<Documentation>;
 }
diff --git a/crates/ra_hir_def/src/docs.rs b/crates/ra_hir_def/src/docs.rs
new file mode 100644
index 000000000..1b5c85437
--- /dev/null
+++ b/crates/ra_hir_def/src/docs.rs
@@ -0,0 +1,68 @@
+//! FIXME: write short doc here
+
+use std::sync::Arc;
+
+use hir_expand::either::Either;
+use ra_syntax::ast;
+
+use crate::{db::DefDatabase2, AdtId, AstItemDef, AttrDefId, HasChildSource, HasSource, Lookup};
+
+/// Holds documentation
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct Documentation(Arc<str>);
+
+impl Into<String> for Documentation {
+    fn into(self) -> String {
+        self.as_str().to_owned()
+    }
+}
+
+impl Documentation {
+    fn new(s: &str) -> Documentation {
+        Documentation(s.into())
+    }
+
+    pub fn as_str(&self) -> &str {
+        &*self.0
+    }
+
+    pub(crate) fn documentation_query(
+        db: &impl DefDatabase2,
+        def: AttrDefId,
+    ) -> Option<Documentation> {
+        match def {
+            AttrDefId::ModuleId(module) => {
+                let def_map = db.crate_def_map(module.krate);
+                let src = def_map[module.module_id].declaration_source(db)?;
+                docs_from_ast(&src.value)
+            }
+            AttrDefId::StructFieldId(it) => {
+                let src = it.parent.child_source(db);
+                match &src.value[it.local_id] {
+                    Either::A(_tuple) => None,
+                    Either::B(record) => docs_from_ast(record),
+                }
+            }
+            AttrDefId::AdtId(it) => match it {
+                AdtId::StructId(it) => docs_from_ast(&it.0.source(db).value),
+                AdtId::EnumId(it) => docs_from_ast(&it.source(db).value),
+                AdtId::UnionId(it) => docs_from_ast(&it.0.source(db).value),
+            },
+            AttrDefId::EnumVariantId(it) => {
+                let src = it.parent.child_source(db);
+                docs_from_ast(&src.value[it.local_id])
+            }
+            AttrDefId::StaticId(it) => docs_from_ast(&it.source(db).value),
+            AttrDefId::TraitId(it) => docs_from_ast(&it.source(db).value),
+            AttrDefId::MacroDefId(it) => docs_from_ast(&it.ast_id.to_node(db)),
+            AttrDefId::ConstId(it) => docs_from_ast(&it.lookup(db).source(db).value),
+            AttrDefId::FunctionId(it) => docs_from_ast(&it.lookup(db).source(db).value),
+            AttrDefId::TypeAliasId(it) => docs_from_ast(&it.lookup(db).source(db).value),
+            AttrDefId::ImplId(_) => None,
+        }
+    }
+}
+
+pub(crate) fn docs_from_ast(node: &impl ast::DocCommentsOwner) -> Option<Documentation> {
+    node.doc_comment_text().map(|it| Documentation::new(&it))
+}
diff --git a/crates/ra_hir_def/src/lib.rs b/crates/ra_hir_def/src/lib.rs
index 899510be4..1ba7c7ee3 100644
--- a/crates/ra_hir_def/src/lib.rs
+++ b/crates/ra_hir_def/src/lib.rs
@@ -20,6 +20,7 @@ pub mod generics;
 pub mod resolver;
 pub mod data;
 pub mod lang_item;
+pub mod docs;
 
 mod trace;
 
diff --git a/crates/ra_ide_api/src/db.rs b/crates/ra_ide_api/src/db.rs
index c96465b6a..7d35d2137 100644
--- a/crates/ra_ide_api/src/db.rs
+++ b/crates/ra_ide_api/src/db.rs
@@ -21,7 +21,6 @@ use crate::{
     symbol_index::SymbolsDatabaseStorage,
     hir::db::InternDatabaseStorage,
     hir::db::AstDatabaseStorage,
-    hir::db::DefDatabaseStorage,
     hir::db::DefDatabase2Storage,
     hir::db::HirDatabaseStorage
 )]