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/dozer/dozer-cli/src
    
    the code of the file until where you have to start completion: use crate::config_helper::add_file_content_to_config;
use dozer_types::models::config::Config;
use dozer_types::serde_yaml;
use dozer_types::serde_yaml::Mappin
    
fn test_sql_from_single_sql_source_in_config() {
    let query = "select * from table_b";

    let yaml = r#"
    app_name: dozer-config-sample
    version: 1
    "#;

    let mut combined_yaml = serde_yaml::Value::Mapping(Mapping::new());

    add_file_content_to_config(&mut combined_yaml, "config.yaml", yaml.into()).unwrap();
    add_file_content_to_config(&mut combined_yaml, "query.sql", query.into()).unwrap();

    let config = serde_yaml::from_value::<Config>(combined_yaml).unwrap();

    assert_eq!(config.sql, Some(query.to_string()));
}