foxhunt/testing/integration/fixtures/helpers.rs

/// Decimal Conversion Helpers for Tests
///
/// Provides utilities to safely convert between f64 and Decimal types in test code.
///
/// Production code should use Decimal throughout, but tests often need to work with
/// floating point values for convenience.
use rust_decimal::Decimal;
pub use rust_decimal_macros::dec;

/// Trait to convert f64 to Decimal safely
pub trait ToDecimal {
    fn to_decimal(self) -> Decimal;
}

impl ToDecimal for f64 {
    /// Convert f64 to Decimal, returning ZERO on failure
    fn to_decimal(self) -> Decimal {
        Decimal::from_f64_retain(self).unwrap_or(Decimal::ZERO)
    }
}

impl ToDecimal for i32 {
    /// Convert i32 to Decimal safely
    fn to_decimal(self) -> Decimal {
        Decimal::from(self)
    }
}

impl ToDecimal for i64 {
    /// Convert i64 to Decimal safely
    fn to_decimal(self) -> Decimal {
        Decimal::from(self)
    }
}

impl ToDecimal for u32 {
    /// Convert u32 to Decimal safely
    fn to_decimal(self) -> Decimal {
        Decimal::from(self)
    }
}

impl ToDecimal for u64 {
    /// Convert u64 to Decimal safely
    fn to_decimal(self) -> Decimal {
        Decimal::from(self)
    }
}

/// Convert f64 to Decimal (convenience function)
pub fn decimal(f: f64) -> Decimal {
    f.to_decimal()
}

/// Convert f64 to Decimal with explicit error message
pub fn decimal_or_panic(f: f64, msg: &str) -> Decimal {
    Decimal::from_f64_retain(f).expect(msg)
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_f64_to_decimal() {
        let d = 100.5.to_decimal();
        assert_eq!(d.to_string(), "100.5");

        let d2 = decimal(200.75);
        assert_eq!(d2.to_string(), "200.75");
    }

    #[test]
    fn test_integer_to_decimal() {
        let d1 = 100i32.to_decimal();
        assert_eq!(d1, Decimal::from(100));

        let d2 = 1000u64.to_decimal();
        assert_eq!(d2, Decimal::from(1000));
    }

    #[test]
    fn test_nan_returns_zero() {
        let d = f64::NAN.to_decimal();
        assert_eq!(d, Decimal::ZERO);
    }

    #[test]
    fn test_infinity_returns_zero() {
        let d = f64::INFINITY.to_decimal();
        assert_eq!(d, Decimal::ZERO);
    }
}