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: helper.rs
    path of file: ./repos/dozer/dozer-cli/src/cli
    
    the code of the file until where you have to start completion: use crate::config_helper::combine_config;
use crate::errors::CliError;
use crate::errors::CliError::{ConfigurationFilePathNotProvided, FailedToFindConfigurationFiles};
use crate::errors::ConfigCombineError::CannotReadConf
    
    fn test_override_top_level() {
        let mut config = Config {
            app_name: "test_override_top_level".to_string(),
            ..Default::default()
        };
        config.sql = Some("sql1".to_string());
        let sql = "sql2".to_string();
        let config = apply_overrides(
            &config,
            vec![("/sql".to_string(), serde_json::to_value(&sql).unwrap())],
        )
        .unwrap();
        assert_eq!(config.sql.unwrap(), sql);
    }