diff --git a/src/common/io/rewind.rs b/src/common/io/rewind.rs
index c2556f013d..c1f7a4f1b9 100644
--- a/src/common/io/rewind.rs
+++ b/src/common/io/rewind.rs
@@ -156,5 +156,7 @@ mod tests {
 
         let mut buf = [0; 5];
         stream.read_exact(&mut buf).await.expect("read1");
+
+        assert_eq!(&buf, &underlying);
     }
 }