1 files changed, 8 insertions, 0 deletions

diff --git a/crates/ra_hir_def/src/trace.rs b/crates/ra_hir_def/src/trace.rs
index 9769e88df..2bcd707bc 100644
--- a/crates/ra_hir_def/src/trace.rs
+++ b/crates/ra_hir_def/src/trace.rs
@@ -18,6 +18,10 @@ pub(crate) struct Trace<ID: ArenaId, T, V> {
 }
 
 impl<ID: ra_arena::ArenaId + Copy, T, V> Trace<ID, T, V> {
+    pub(crate) fn new() -> Trace<ID, T, V> {
+        Trace { arena: Some(Arena::default()), map: Some(ArenaMap::default()), len: 0 }
+    }
+
     pub(crate) fn new_for_arena() -> Trace<ID, T, V> {
         Trace { arena: Some(Arena::default()), map: None, len: 0 }
     }
@@ -48,4 +52,8 @@ impl<ID: ra_arena::ArenaId + Copy, T, V> Trace<ID, T, V> {
     pub(crate) fn into_map(mut self) -> ArenaMap<ID, V> {
         self.map.take().unwrap()
     }
+
+    pub(crate) fn into_arena_and_map(mut self) -> (Arena<ID, T>, ArenaMap<ID, V>) {
+        (self.arena.take().unwrap(), self.map.take().unwrap())
+    }
 }