2 files changed, 19 insertions, 4 deletions

diff --git a/crates/ra_ide_api/src/db.rs b/crates/ra_ide_api/src/db.rs
index cccf0ada4..b3f395502 100644
--- a/crates/ra_ide_api/src/db.rs
+++ b/crates/ra_ide_api/src/db.rs
@@ -41,6 +41,12 @@ impl salsa::Database for RootDatabase {
 
 impl Default for RootDatabase {
     fn default() -> RootDatabase {
+        RootDatabase::new(None)
+    }
+}
+
+impl RootDatabase {
+    pub fn new(lru_capacity: Option<usize>) -> RootDatabase {
         let mut db = RootDatabase {
             runtime: salsa::Runtime::default(),
             last_gc: time::Instant::now(),
@@ -49,9 +55,9 @@ impl Default for RootDatabase {
         db.set_crate_graph(Default::default());
         db.set_local_roots(Default::default());
         db.set_library_roots(Default::default());
-        let lru_cap = ra_db::DEFAULT_LRU_CAP;
-        db.query_mut(ra_db::ParseQuery).set_lru_capacity(lru_cap);
-        db.query_mut(hir::db::ParseMacroQuery).set_lru_capacity(lru_cap);
+        let lru_capacity = lru_capacity.unwrap_or(ra_db::DEFAULT_LRU_CAP);
+        db.query_mut(ra_db::ParseQuery).set_lru_capacity(lru_capacity);
+        db.query_mut(hir::db::ParseMacroQuery).set_lru_capacity(lru_capacity);
         db
     }
 }
diff --git a/crates/ra_ide_api/src/lib.rs b/crates/ra_ide_api/src/lib.rs
index dbebf50a6..8741e736f 100644
--- a/crates/ra_ide_api/src/lib.rs
+++ b/crates/ra_ide_api/src/lib.rs
@@ -242,12 +242,21 @@ pub struct CallInfo {
 }
 
 /// `AnalysisHost` stores the current state of the world.
-#[derive(Debug, Default)]
+#[derive(Debug)]
 pub struct AnalysisHost {
     db: db::RootDatabase,
 }
 
+impl Default for AnalysisHost {
+    fn default() -> AnalysisHost {
+        AnalysisHost::new(None)
+    }
+}
+
 impl AnalysisHost {
+    pub fn new(lru_capcity: Option<usize>) -> AnalysisHost {
+        AnalysisHost { db: db::RootDatabase::new(lru_capcity) }
+    }
     /// Returns a snapshot of the current state, which you can query for
     /// semantic information.
     pub fn analysis(&self) -> Analysis {