slint/helper_crates/const-field-offset/tests/test_field_offset.rs

// Copyright © SixtyFPS GmbH <info@slint.dev>
// SPDX-License-Identifier: MIT OR Apache-2.0

use const_field_offset::*;
use memoffset::offset_of;
use std::sync::atomic::Ordering::SeqCst;

#[derive(FieldOffsets)]
#[repr(C)]
struct MyStruct {
    a: u8,
    b: u16,
    c: u8,
    d: u16,
}

#[derive(FieldOffsets)]
#[repr(C)]
struct MyStruct2 {
    k: core::cell::Cell<isize>,
    xx: MyStruct,
    v: u32,
}

#[derive(FieldOffsets)]
#[repr(C)]
#[allow(unused)]
struct MyStruct3 {
    ms2: MyStruct2,
}

const XX_CONST: usize = MyStruct2::FIELD_OFFSETS.xx.get_byte_offset();
static D_STATIC: usize = MyStruct::FIELD_OFFSETS.d.get_byte_offset();

#[test]
fn test() {
    assert_eq!(offset_of!(MyStruct, a), MyStruct::FIELD_OFFSETS.a.get_byte_offset());
    assert_eq!(offset_of!(MyStruct, b), MyStruct::FIELD_OFFSETS.b.get_byte_offset());
    assert_eq!(offset_of!(MyStruct, c), MyStruct::FIELD_OFFSETS.c.get_byte_offset());
    assert_eq!(offset_of!(MyStruct, d), MyStruct::FIELD_OFFSETS.d.get_byte_offset());
    assert_eq!(offset_of!(MyStruct2, xx), MyStruct2::FIELD_OFFSETS.xx.get_byte_offset());
    assert_eq!(offset_of!(MyStruct2, v), MyStruct2::FIELD_OFFSETS.v.get_byte_offset());
    assert_eq!(offset_of!(MyStruct2, k), MyStruct2::FIELD_OFFSETS.k.get_byte_offset());

    assert_eq!(XX_CONST, offset_of!(MyStruct2, xx));
    assert_eq!(D_STATIC, offset_of!(MyStruct, d));
}

#[test]
#[cfg(feature = "field-offset-trait")]
fn test_module() {
    assert_eq!(offset_of!(MyStruct, a), MyStruct_field_offsets::a.get_byte_offset());
    assert_eq!(offset_of!(MyStruct, b), MyStruct_field_offsets::b.get_byte_offset());
    assert_eq!(offset_of!(MyStruct, c), MyStruct_field_offsets::c.get_byte_offset());
    assert_eq!(offset_of!(MyStruct, d), MyStruct_field_offsets::d.get_byte_offset());
    assert_eq!(offset_of!(MyStruct2, xx), MyStruct2_field_offsets::xx.get_byte_offset());
    assert_eq!(offset_of!(MyStruct2, v), MyStruct2_field_offsets::v.get_byte_offset());
    assert_eq!(offset_of!(MyStruct2, k), MyStruct2_field_offsets::k.get_byte_offset());

    assert_eq!(core::mem::size_of::<MyStruct_field_offsets::c>(), 0);

    let d_in_ms2 = MyStruct2_field_offsets::xx + MyStruct_field_offsets::d;
    assert_eq!(offset_of!(MyStruct2, xx) + offset_of!(MyStruct, d), d_in_ms2.get_byte_offset());
    assert_eq!(core::mem::size_of_val(&d_in_ms2), 0);

    let a = MyStruct3_field_offsets::ms2 + d_in_ms2;
    let b = MyStruct3_field_offsets::ms2 + MyStruct2_field_offsets::xx + MyStruct_field_offsets::d;
    assert_eq!(a.get_byte_offset(), b.get_byte_offset());
}

#[derive(FieldOffsets)]
#[repr(C)]
#[pin]
struct MyStructPin {
    phantom: core::marker::PhantomPinned,
    pub a: u8,
    b: u16,
    c: u8,
    d: u16,
}

#[derive(FieldOffsets)]
#[repr(C)]
#[pin]
struct MyStruct2Pin {
    phantom: core::marker::PhantomPinned,
    k: core::cell::Cell<isize>,
    xx: MyStruct,
    v: u32,
}

const XX_CONST_PIN: usize = MyStruct2Pin::FIELD_OFFSETS.xx.get_byte_offset();
static D_STATIC_PIN: usize = MyStructPin::FIELD_OFFSETS.d.get_byte_offset();

#[test]
fn test_pin() {
    assert_eq!(offset_of!(MyStructPin, a), MyStructPin::FIELD_OFFSETS.a.get_byte_offset());
    assert_eq!(offset_of!(MyStructPin, b), MyStructPin::FIELD_OFFSETS.b.get_byte_offset());
    assert_eq!(offset_of!(MyStructPin, c), MyStructPin::FIELD_OFFSETS.c.get_byte_offset());
    assert_eq!(offset_of!(MyStructPin, d), MyStructPin::FIELD_OFFSETS.d.get_byte_offset());
    assert_eq!(offset_of!(MyStruct2Pin, xx), MyStruct2Pin::FIELD_OFFSETS.xx.get_byte_offset());
    assert_eq!(offset_of!(MyStruct2Pin, v), MyStruct2Pin::FIELD_OFFSETS.v.get_byte_offset());
    assert_eq!(offset_of!(MyStruct2Pin, k), MyStruct2Pin::FIELD_OFFSETS.k.get_byte_offset());

    assert_eq!(XX_CONST_PIN, offset_of!(MyStruct2Pin, xx));
    assert_eq!(D_STATIC_PIN, offset_of!(MyStructPin, d));
}

static DROP_CALLED: std::sync::atomic::AtomicBool = std::sync::atomic::AtomicBool::new(false);

#[derive(FieldOffsets)]
#[repr(C)]
#[pin]
#[pin_drop]
struct MyPinnedStructWithDrop {
    x: u32,
}

impl PinnedDrop for MyPinnedStructWithDrop {
    fn drop(self: core::pin::Pin<&mut MyPinnedStructWithDrop>) {
        DROP_CALLED.store(true, SeqCst);
    }
}

#[test]
fn test_pin_drop() {
    DROP_CALLED.store(false, SeqCst);
    {
        let _instance = Box::pin(MyPinnedStructWithDrop { x: 42 });
    }
    assert!(DROP_CALLED.load(SeqCst));
}

mod priv_mod {
    #[derive(const_field_offset::FieldOffsets)]
    #[repr(C)]
    struct PrivStruct {
        pub a: u32,
        pub b: Vec<PrivStruct>,
    }

    #[allow(unused)]
    #[derive(const_field_offset::FieldOffsets)]
    #[repr(C)]
    pub struct PubStruct {
        pub a: u32,
        b: Vec<PrivStruct>,
        pub r#mod: Vec<PubStruct>,
    }
}