From 40624b83d209bf5b5a7fad6f637071efd05b378f Mon Sep 17 00:00:00 2001
From: Alexey Orlenko <alex@aqrln.net>
Date: Fri, 25 Apr 2025 20:04:56 +0200
Subject: [PATCH] Consume the `Responses` in `Statement::drop`

Instead of dropping the `Responses` in `Statement::drop` and closing the
channel stored in there, poll the response messages from it.
---
 tokio-postgres/Cargo.toml       |  2 +-
 tokio-postgres/src/statement.rs | 18 +++++++++++++++++-
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/tokio-postgres/Cargo.toml b/tokio-postgres/Cargo.toml
index 77b0ec700..d619c19ce 100644
--- a/tokio-postgres/Cargo.toml
+++ b/tokio-postgres/Cargo.toml
@@ -60,7 +60,7 @@ phf = "0.11"
 postgres-protocol = { version = "0.6.8", path = "../postgres-protocol" }
 postgres-types = { version = "0.2.9", path = "../postgres-types" }
 socket2 = "0.5.3"
-tokio = { version = "1.27", features = ["io-util"] }
+tokio = { version = "1.27", features = ["io-util", "rt"] }
 tokio-util = { version = "0.7", features = ["codec"] }
 rand = "0.9.0"
 whoami = "1.4.1"
diff --git a/tokio-postgres/src/statement.rs b/tokio-postgres/src/statement.rs
index bf9db30bb..1e9aba5fb 100644
--- a/tokio-postgres/src/statement.rs
+++ b/tokio-postgres/src/statement.rs
@@ -2,6 +2,7 @@ use crate::client::InnerClient;
 use crate::codec::FrontendMessage;
 use crate::connection::RequestMessages;
 use crate::types::Type;
+use postgres_protocol::message::backend::Message;
 use postgres_protocol::message::frontend;
 use std::fmt;
 use std::sync::{Arc, Weak};
@@ -19,13 +20,28 @@ impl Drop for StatementInner {
             // Unnamed statements don't need to be closed
             return;
         }
+
         if let Some(client) = self.client.upgrade() {
             let buf = client.with_buf(|buf| {
                 frontend::close(b'S', &self.name, buf).unwrap();
                 frontend::sync(buf);
                 buf.split().freeze()
             });
-            let _ = client.send(RequestMessages::Single(FrontendMessage::Raw(buf)));
+
+            let response = client.send(RequestMessages::Single(FrontendMessage::Raw(buf)));
+
+            tokio::spawn(async move {
+                let result = async move {
+                    match response?.next().await? {
+                        Message::CloseComplete => Ok(()),
+                        _ => Err(crate::Error::unexpected_message()),
+                    }
+                };
+
+                if let Err(err) = result.await {
+                    log::error!("failed to deallocate prepared statement: {err}");
+                }
+            });
         }
     }
 }