Add and use `IndexVec::append`

1 files changed, 5 insertions, 0 deletions

diff --git a/compiler/rustc_index/src/vec.rs b/compiler/rustc_index/src/vec.rs
index 7438c97eb58..1cb8bc861af 100644
--- a/compiler/rustc_index/src/vec.rs
+++ b/compiler/rustc_index/src/vec.rs
@@ -188,6 +188,11 @@ impl<I: Idx, T> IndexVec<I, T> {
         let min_new_len = elem.index() + 1;
         self.raw.resize_with(min_new_len, fill_value);
     }
+
+    #[inline]
+    pub fn append(&mut self, other: &mut Self) {
+        self.raw.append(&mut other.raw);
+    }
 }
 
 /// `IndexVec` is often used as a map, so it provides some map-like APIs.