2 files changed, 14 insertions, 9 deletions

diff --git a/crates/ra_ide_api/src/db.rs b/crates/ra_ide_api/src/db.rs
index 02e12437c..119190e0a 100644
--- a/crates/ra_ide_api/src/db.rs
+++ b/crates/ra_ide_api/src/db.rs
@@ -1,11 +1,11 @@
 use std::sync::Arc;
 
 use ra_db::{
-    CheckCanceled, FileId, Canceled,
-    salsa::{self, Database},
+    CheckCanceled, FileId, Canceled, FilesDatabase,
+    salsa,
 };
 
-use crate::{symbol_index, LineIndex};
+use crate::{LineIndex, symbol_index::{self, SymbolsDatabase}};
 
 #[salsa::database(
     ra_db::FilesDatabaseStorage,
@@ -34,12 +34,9 @@ impl Default for RootDatabase {
             runtime: salsa::Runtime::default(),
             interner: Default::default(),
         };
-        db.query_mut(ra_db::CrateGraphQuery)
-            .set((), Default::default());
-        db.query_mut(ra_db::LocalRootsQuery)
-            .set((), Default::default());
-        db.query_mut(ra_db::LibraryRootsQuery)
-            .set((), Default::default());
+        db.set_crate_graph(Default::default());
+        db.set_local_roots(Default::default());
+        db.set_library_roots(Default::default());
         db
     }
 }
diff --git a/crates/ra_ide_api/src/symbol_index.rs b/crates/ra_ide_api/src/symbol_index.rs
index e073a349e..4d81d14b3 100644
--- a/crates/ra_ide_api/src/symbol_index.rs
+++ b/crates/ra_ide_api/src/symbol_index.rs
@@ -49,6 +49,14 @@ pub(crate) trait SymbolsDatabase: hir::db::HirDatabase {
     fn file_symbols(&self, file_id: FileId) -> Arc<SymbolIndex>;
     #[salsa::input]
     fn library_symbols(&self, id: SourceRootId) -> Arc<SymbolIndex>;
+    /// The set of "local" (that is, from the current workspace) roots.
+    /// Files in local roots are assumed to change frequently.
+    #[salsa::input]
+    fn local_roots(&self) -> Arc<Vec<SourceRootId>>;
+    /// The set of roots for crates.io libraries.
+    /// Files in libraries are assumed to never change.
+    #[salsa::input]
+    fn library_roots(&self) -> Arc<Vec<SourceRootId>>;
 }
 
 fn file_symbols(db: &impl SymbolsDatabase, file_id: FileId) -> Arc<SymbolIndex> {