trail-config 0.4.0

A Rust library for reading config files with path-based access, typed deserialization, environment overlays, deep merging, env variable interpolation, and hot reload support.
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use super::{Config, ConfigError, YAML};

#[test]
fn get_as_strict_success() {
    #[derive(serde::Deserialize, Debug, PartialEq)]
    struct RedisConfig {
        server: String,
        port: u16,
        key_expiry: u32,
    }

    let config = Config::load_yaml(YAML, "/").unwrap();
    let redis: RedisConfig = config.get_as_strict("db/redis").unwrap();

    assert_eq!(redis.server, "127.0.0.1");
    assert_eq!(redis.port, 6379);
    assert_eq!(redis.key_expiry, 3600);
}

#[test]
fn get_as_strict_path_not_found() {
    #[derive(serde::Deserialize)]
    #[allow(dead_code)]
    struct Dummy { value: String }

    let config = Config::load_yaml(YAML, "/").unwrap();
    let result = config.get_as_strict::<Dummy>("db/nonexistent");

    assert!(result.is_err());
    match result {
        Err(ConfigError::PathNotFound(_)) => (),
        _ => panic!("Expected PathNotFound"),
    }
}

#[test]
fn get_as_strict_type_mismatch() {
    #[derive(serde::Deserialize, Debug)]
    #[allow(dead_code)]
    struct Wrong { totally_made_up_field: String }

    let config = Config::load_yaml(YAML, "/").unwrap();
    let result = config.get_as_strict::<Wrong>("db/redis/port");

    assert!(result.is_err());
    match result {
        Err(ConfigError::YamlError(_)) => (),
        _ => panic!("Expected YamlError"),
    }
}

#[test]
fn get_as_lenient_returns_none_on_missing() {
    #[derive(serde::Deserialize)]
    #[allow(dead_code)]
    struct Dummy { value: String }

    let config = Config::load_yaml(YAML, "/").unwrap();
    let result = config.get_as::<Dummy>("nonexistent/path");

    assert!(result.is_none());
}

#[test]
fn get_as_nested_struct() {
    #[derive(serde::Deserialize, Debug, PartialEq)]
    struct AppConfig {
        debug: bool,
        max_retries: i32,
        timeout: f64,
    }

    let config = Config::load_yaml(YAML, "/").unwrap();
    let app: AppConfig = config.get_as_strict("app").unwrap();

    assert_eq!(app.debug, true);
    assert_eq!(app.max_retries, 5);
    assert!((app.timeout - 2.5).abs() < 0.001);
}

#[test]
fn deserialize_strict_full_config() {
    #[derive(serde::Deserialize, Debug)]
    struct FullConfig {
        db: DbConfig,
        app: AppConfig,
    }
    #[derive(serde::Deserialize, Debug)]
    struct DbConfig {
        redis: RedisConfig,
    }
    #[derive(serde::Deserialize, Debug)]
    struct RedisConfig {
        server: String,
        port: u16,
        key_expiry: u32,
    }
    #[derive(serde::Deserialize, Debug)]
    struct AppConfig {
        debug: bool,
        max_retries: i32,
        timeout: f64,
    }

    let config = Config::load_yaml(YAML, "/").unwrap();
    let full: FullConfig = config.deserialize_strict().unwrap();

    assert_eq!(full.db.redis.server, "127.0.0.1");
    assert_eq!(full.db.redis.port, 6379);
    assert_eq!(full.db.redis.key_expiry, 3600);
    assert_eq!(full.app.debug, true);
    assert_eq!(full.app.max_retries, 5);
    assert!((full.app.timeout - 2.5).abs() < 0.001);
}

#[test]
fn deserialize_strict_type_mismatch() {
    #[derive(serde::Deserialize)]
    #[allow(dead_code)]
    struct Wrong { totally_made_up_field: String }

    let config = Config::load_yaml(YAML, "/").unwrap();
    let result = config.deserialize_strict::<Wrong>();

    assert!(result.is_err());
    match result {
        Err(ConfigError::YamlError(_)) => (),
        _ => panic!("Expected YamlError"),
    }
}

#[test]
fn deserialize_lenient_returns_none_on_mismatch() {
    #[derive(serde::Deserialize)]
    #[allow(dead_code)]
    struct Wrong { totally_made_up_field: String }

    let config = Config::load_yaml(YAML, "/").unwrap();
    let result = config.deserialize::<Wrong>();

    assert!(result.is_none());
}

#[test]
fn deserialize_strict_empty_config() {
    #[derive(serde::Deserialize, Debug, PartialEq)]
    struct NonEmpty { required_field: String }

    let config = Config::load_yaml("", "/").unwrap();
    let result = config.deserialize_strict::<NonEmpty>();

    assert!(result.is_err());
    match result {
        Err(ConfigError::YamlError(_)) => (),
        _ => panic!("Expected YamlError for empty config"),
    }
}