diff --git a/crates/project/Cargo.toml b/crates/project/Cargo.toml
index 23ab43c46b7c03d393e2d405d93c238da963c112..ea5a852f781223f3626d86963812eff87a949014 100644
--- a/crates/project/Cargo.toml
+++ b/crates/project/Cargo.toml
@@ -14,6 +14,7 @@ doctest = false
 
 [features]
 test-support = [
+    "buffer_diff/test-support",
     "client/test-support",
     "language/test-support",
     "settings/test-support",