You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: tests.rs
    path of file: ./repos/skytable/server/src/engine/storage/v2/raw/journal
    
    the code of the file until where you have to start completion: /*
 * Created on Fri Feb 09 2024
 *
 * This file is a part of Skytable
 * Skytable (formerly known as TerrabaseDB or Skybase) is a free and open-source
 * NoSQL database written by Sayan Nandan ("the Author") with the
 * 
    
    fn push(&self, driver: &mut BatchDriver<BatchDBAdapter>, key: &str) -> RuntimeResult<()> {
        let mut me = self._mut();
        me.data.push(key.into());
        let changed = me.data.len() - me.last_flushed_at;
        if changed == 2 {
            // this is the second change about to happen, so flush it!
            driver.commit_event(BatchDBFlush(&me, me.data.len()))?;
            me.last_flushed_at = me.data.len();
        }
        Ok(())
    }