Remove useless flush fn on postgres raw conn

src/postgres/connection/establish.rs

@@ -38,7 +38,7 @@ pub async fn establish<'a, 'b: 'a>(
     let message = StartupMessage { params };
 
     conn.write(message);
-    conn.flush().await?;
+    conn.stream.flush().await?;
 
     while let Some(message) = conn.receive().await? {
         match message {
@@ -52,7 +52,7 @@ pub async fn establish<'a, 'b: 'a>(
                         // FIXME: Should error early (before send) if the user did not supply a password
                         conn.write(PasswordMessage::Cleartext(password));
 
-                        conn.flush().await?;
+                        conn.stream.flush().await?;
                     }
 
                     Authentication::Md5Password { salt } => {
@@ -63,7 +63,7 @@ pub async fn establish<'a, 'b: 'a>(
                             salt,
                         });
 
-                        conn.flush().await?;
+                        conn.stream.flush().await?;
                     }
 
                     auth => {

src/postgres/connection/execute.rs

@@ -3,7 +3,7 @@ use crate::{error::Error, postgres::protocol::Message};
 use std::io;
 
 pub async fn execute(conn: &mut PostgresRawConnection) -> Result<u64, Error> {
-    conn.flush().await?;
+    conn.stream.flush().await?;
 
     let mut rows = 0;
 

src/postgres/connection/fetch.rs

@@ -7,7 +7,7 @@ pub fn fetch<'a>(
     conn: &'a mut PostgresRawConnection,
 ) -> impl Stream<Item = Result<PostgresRow, Error>> + 'a {
     async_stream::try_stream! {
-        conn.flush().await?;
+        conn.stream.flush().await.map_err(Error::Io)?;
 
         while let Some(message) = conn.receive().await? {
             match message {

src/postgres/connection/fetch_optional.rs

@@ -5,7 +5,7 @@ use std::io;
 pub async fn fetch_optional<'a>(
     conn: &'a mut PostgresRawConnection,
 ) -> Result<Option<PostgresRow>, Error> {
-    conn.flush().await?;
+    conn.stream.flush().await?;
 
     let mut row: Option<PostgresRow> = None;
 

src/postgres/connection/mod.rs

@@ -123,12 +123,6 @@ impl PostgresRawConnection {
     pub(super) fn write(&mut self, message: impl Encode) {
         message.encode(self.stream.buffer_mut());
     }
-
-    async fn flush(&mut self) -> Result<(), Error> {
-        self.stream.flush().await?;
-
-        Ok(())
-    }
 }
 
 impl RawConnection for PostgresRawConnection {