qubit-function 0.16.0

Functional programming traits and Box/Rc/Arc adapters for Rust, inspired by Java functional interfaces
// =============================================================================
//    Copyright (c) 2025 - 2026 Haixing Hu.
//
//    SPDX-License-Identifier: Apache-2.0
//
//    Licensed under the Apache License, Version 2.0.
// =============================================================================

//! Unit tests for StatefulMutator types

use qubit_function::{
    ArcStatefulMutator,
    BoxStatefulMutator,
    MutatorOnce,
    RcStatefulMutator,
    StatefulMutator,
};

// ============================================================================
// BoxStatefulMutator Tests
// ============================================================================

#[cfg(test)]
mod test_unified_interface {
    use super::{
        ArcStatefulMutator,
        BoxStatefulMutator,
        RcStatefulMutator,
        StatefulMutator,
    };

    fn apply_mutator<C: StatefulMutator<i32>>(
        mutator: &mut C,
        value: i32,
    ) -> i32 {
        let mut val = value;
        mutator.apply(&mut val);
        val
    }

    #[test]
    fn test_with_box_consumer() {
        let mut mutator = BoxStatefulMutator::new(|x: &mut i32| *x *= 2);
        assert_eq!(apply_mutator(&mut mutator, 5), 10);
    }

    #[test]
    fn test_with_arc_consumer() {
        let mut mutator = ArcStatefulMutator::new(|x: &mut i32| *x *= 2);
        assert_eq!(apply_mutator(&mut mutator, 5), 10);
    }

    #[test]
    fn test_with_rc_consumer() {
        let mut mutator = RcStatefulMutator::new(|x: &mut i32| *x *= 2);
        assert_eq!(apply_mutator(&mut mutator, 5), 10);
    }

    #[test]
    fn test_with_closure() {
        let mut closure = |x: &mut i32| *x *= 2;
        assert_eq!(apply_mutator(&mut closure, 5), 10);
    }
}

// ============================================================================
// Complex Scenarios Tests
// ============================================================================