diff --git a/Cargo.toml b/Cargo.toml
index 3bc10f3..cf10494 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "tokio-rustls"
-version = "0.12.0-alpha.8"
+version = "0.12.0"
 authors = ["quininer kel <quininer@live.com>"]
 license = "MIT/Apache-2.0"
 repository = "https://github.com/quininer/tokio-rustls"
@@ -15,6 +15,7 @@ edition = "2018"
 github-actions = { repository = "quininer/tokio-rustls", workflow = "ci" }
 
 [dependencies]
+bytes = "0.5"
 tokio = "0.2.0"
 futures-core = "0.3.1"
 rustls = "0.16"
diff --git a/src/client.rs b/src/client.rs
index 470194a..779ddc5 100644
--- a/src/client.rs
+++ b/src/client.rs
@@ -128,8 +128,8 @@ where
                             return Poll::Pending,
                         Err(err) => return Poll::Ready(Err(err))
                     };
-                    data.extend_from_slice(&buf[..len]);
                     if len != 0 {
+                        data.extend_from_slice(&buf[..len]);
                         return Poll::Ready(Ok(len));
                     }
                 }