fix warnings and bugs, noticed on nightly

src/imap/mod.rs

@@ -811,7 +811,6 @@ impl Imap {
                     Ok(_) => Some(server_uid),
                     Err(err) => {
                         warn!(context, "dc_receive_imf error: {}", err);
-                        read_errors += 1;
                         None
                     }
                 }

src/location.rs

@@ -530,7 +530,7 @@ pub async fn save(
             accuracy,
             ..
         } = location;
-        context
+        let (loc_id, ts) = context
             .sql
             .with_conn(move |mut conn| {
                 let mut stmt_test = conn
@@ -569,9 +569,11 @@ pub async fn save(
                         )?;
                     }
                 }
-                Ok(())
+                Ok((newest_location_id, newest_timestamp))
             })
             .await?;
+        newest_timestamp = ts;
+        newest_location_id = loc_id;
     }
 
     Ok(newest_location_id)

src/mimeparser.rs

@@ -257,7 +257,8 @@ impl MimeMessage {
                 self.parts[0].msg = "".to_string();
 
                 // swap new with old
-                std::mem::replace(&mut self.parts[0], filepart);
+                self.parts.push(filepart); // push to the end
+                let _ = self.parts.swap_remove(0); // drops first element, replacing it with the last one in O(1)
             }
         }
     }