rs_bindings_from_cc/test/function/non_extern_c/test.rs

// Part of the Crubit project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

#[cfg(test)]
mod tests {
    #[test]
    fn test_return_value() {
        use simple_functions::return_value;
        assert_eq!(return_value(), 42);
    }

    #[test]
    fn test_return_pointer() {
        use simple_functions::return_pointer;
        unsafe {
            assert_eq!(*return_pointer(), 42);
        }
    }

    #[test]
    fn test_return_reference() {
        use simple_functions::return_reference;
        unsafe {
            assert_eq!(*return_reference(), 42);
        }
    }

    #[test]
    fn test_take_pointer() {
        use simple_functions::take_pointer;
        unsafe {
            take_pointer(std::ptr::null_mut());
        }
        let mut i: i32 = 0;
        unsafe {
            take_pointer(&mut i);
        }
        assert_eq!(i, 42);
    }

    #[test]
    fn test_take_reference() {
        use simple_functions::take_reference;
        let mut i: i32 = 0;
        unsafe {
            take_reference(&mut i);
        }
        assert_eq!(i, 42);
    }

    #[test]
    fn test_forward_pointer() {
        use simple_functions::forward_pointer;
        assert_eq!(unsafe { forward_pointer(std::ptr::null()) }, std::ptr::null());
        let i: i32 = 42;
        assert_eq!(unsafe { *forward_pointer(&i) }, 42);
    }

    #[test]
    fn test_forward_reference() {
        use simple_functions::forward_reference;
        let i: i32 = 42;
        assert_eq!(unsafe { *forward_reference(&i) }, 42);
    }

    #[test]
    fn test_multiply() {
        assert_eq!(simple_functions::multiply(42, 123), 42 * 123);
    }

    #[test]
    fn test_multiply_with_unnamed_parameters() {
        assert_eq!(simple_functions::multiply_with_unnamed_parameters(42, 456), 42 * 456);
    }

    #[test]
    fn test_multiply_with_keyword_named_parameters() {
        assert_eq!(
            42 * 123 * 456,
            simple_functions::multiply_with_keyword_named_parameters(42, 123, 456)
        );
    }

    #[test]
    fn test_function_pointer() {
        let maybe_mul_fn = simple_functions::get_pointer_to_multiply_function();
        let mul_fn = maybe_mul_fn.expect("Expecting non-null / non-None function pointer");
        assert_eq!(mul_fn(123, 456), 123 * 456);
    }

    #[test]
    fn test_function_reference() {
        // TODO(b/217419782): Replicate `test_function_pointer`, but for C++
        // references. (e.g. no `expect` / `Option` unwrapping should be
        // needed).
    }

    #[test]
    fn test_function_pointer_returned_from_inline_function() {
        let maybe_mul_fn = simple_functions::inline_get_pointer_to_multiply_function();
        let mul_fn = maybe_mul_fn.expect("Expecting non-null / non-None function pointer");
        assert_eq!(mul_fn(123, 456), 123 * 456);
    }

    /// Test that function pointers can be accepted as function parameters.
    #[test]
    fn test_apply_binary_op() {
        extern "C" fn multiply(x: i32, y: i32) -> i32 {
            x * y
        }
        extern "C" fn add(x: i32, y: i32) -> i32 {
            x + y
        }

        assert_eq!(100 * 200, simple_functions::apply_binary_op(100, 200, Some(multiply)),);
        assert_eq!(300 + 400, simple_functions::apply_binary_op(300, 400, Some(add)),);
    }
}