#[test]
fn os_user_runtime_alloc_positive() {
    let (mut runtime, _, child) = setup();
    activate(&mut runtime, child);
    let baseline = runtime.fixture_backend().primary_inventory();
    let acquisitions = runtime.fixture_backend().runtime_hooks.borrow().acquisitions;
    assert!(matches!(runtime.allocate(1, 3), Err(Error::Invalid)));
    assert_eq!(runtime.fixture_backend().runtime_hooks.borrow().acquisitions,
        acquisitions);
    let mut buffers = Vec::new();
    for (index, capacity) in [16, 32, 64].into_iter().enumerate() {
        let buffer = runtime.allocate(capacity, 16).unwrap();
        for position in 0..capacity {
            runtime.push(&buffer, (index as u8) ^ (position as u8)).unwrap();
        }
        buffers.push(buffer);
    }
    assert_eq!(runtime.fixture_backend().heap_inventory(),
        Inventory { pages: 3, pins: 3 });
    for (index, buffer) in buffers.iter().enumerate() {
        for position in 0..[16, 32, 64][index] {
            assert_eq!(runtime.read(buffer, position),
                Ok((index as u8) ^ (position as u8)));
        }
    }
    for buffer in buffers { runtime.free(buffer).ok().unwrap(); }
    assert_eq!(runtime.fixture_backend().heap_inventory(),
        Inventory { pages: 0, pins: 0 });
    assert_eq!(runtime.fixture_backend().primary_inventory(), baseline);
}

#[test]
fn os_user_runtime_alloc_negative() {
    let (mut runtime, shell, child) = setup();
    activate(&mut runtime, child);
    let baseline = runtime.fixture_backend().primary_inventory();
    let buffers: Vec<_> = (0..3).map(|_| runtime.allocate(1, 1).unwrap()).collect();
    let acquisitions = runtime.fixture_backend().runtime_hooks.borrow().acquisitions;
    let full = runtime.fixture_backend().primary_inventory();
    assert!(matches!(runtime.allocate(1, 1), Err(Error::NoMem)));
    assert_eq!(runtime.fixture_backend().runtime_hooks.borrow().acquisitions,
        acquisitions);
    assert_eq!(runtime.fixture_backend().primary_inventory(), full);
    activate(&mut runtime, shell);
    let healthy = runtime.allocate(8, 8).unwrap();
    runtime.push(&healthy, 0x5a).unwrap();
    assert_eq!(runtime.read(&healthy, 0), Ok(0x5a));
    assert_eq!(runtime.fixture_backend().record(shell).resources.state,
        threads::State::Running);
    runtime.free(healthy).ok().unwrap();
    activate(&mut runtime, child);
    for buffer in buffers { runtime.free(buffer).ok().unwrap(); }
    assert_eq!(runtime.fixture_backend().heap_inventory(),
        Inventory { pages: 0, pins: 0 });
    assert_eq!(runtime.fixture_backend().primary_inventory(), baseline);
}