2 files changed, 6 insertions, 3 deletions

diff --git a/crates/ra_hir/src/db.rs b/crates/ra_hir/src/db.rs
index 6b21fe744..e03632519 100644
--- a/crates/ra_hir/src/db.rs
+++ b/crates/ra_hir/src/db.rs
@@ -103,3 +103,8 @@ pub trait HirDatabase: PersistentHirDatabase {
     #[salsa::invoke(crate::ty::method_resolution::CrateImplBlocks::impls_in_crate_query)]
     fn impls_in_crate(&self, krate: Crate) -> Arc<CrateImplBlocks>;
 }
+
+#[test]
+fn hir_database_is_object_safe() {
+    fn _assert_object_safe(_: &dyn HirDatabase) {}
+}
diff --git a/crates/ra_hir/src/mock.rs b/crates/ra_hir/src/mock.rs
index 17bdd48c6..00a07d1a1 100644
--- a/crates/ra_hir/src/mock.rs
+++ b/crates/ra_hir/src/mock.rs
@@ -2,7 +2,7 @@ use std::{sync::Arc, panic};
 
 use parking_lot::Mutex;
 use ra_db::{
-    CheckCanceled, FilePosition, FileId, CrateGraph, SourceRoot, SourceRootId, SourceDatabase, salsa,
+    FilePosition, FileId, CrateGraph, SourceRoot, SourceRootId, SourceDatabase, salsa,
 };
 use relative_path::RelativePathBuf;
 use test_utils::{parse_fixture, CURSOR_MARKER, extract_offset};
@@ -159,8 +159,6 @@ impl salsa::ParallelDatabase for MockDatabase {
     }
 }
 
-impl CheckCanceled for MockDatabase {}
-
 impl AsRef<HirInterner> for MockDatabase {
     fn as_ref(&self) -> &HirInterner {
         &self.interner