pyo3/tests/test_gc.rs
2021-03-26 13:21:38 +08:00

315 lines
8 KiB
Rust

use pyo3::class::PyGCProtocol;
use pyo3::class::PyTraverseError;
use pyo3::class::PyVisit;
use pyo3::prelude::*;
use pyo3::type_object::PyTypeObject;
use pyo3::{py_run, AsPyPointer, PyCell, PyTryInto};
use std::sync::atomic::{AtomicBool, Ordering};
use std::sync::Arc;
mod common;
#[pyclass(freelist = 2)]
struct ClassWithFreelist {}
#[test]
fn class_with_freelist() {
let ptr;
{
let gil = Python::acquire_gil();
let py = gil.python();
let inst = Py::new(py, ClassWithFreelist {}).unwrap();
let _inst2 = Py::new(py, ClassWithFreelist {}).unwrap();
ptr = inst.as_ptr();
drop(inst);
}
{
let gil = Python::acquire_gil();
let py = gil.python();
let inst3 = Py::new(py, ClassWithFreelist {}).unwrap();
assert_eq!(ptr, inst3.as_ptr());
let inst4 = Py::new(py, ClassWithFreelist {}).unwrap();
assert_ne!(ptr, inst4.as_ptr())
}
}
struct TestDropCall {
drop_called: Arc<AtomicBool>,
}
impl Drop for TestDropCall {
fn drop(&mut self) {
self.drop_called.store(true, Ordering::Relaxed);
}
}
#[allow(dead_code)]
#[pyclass]
struct DataIsDropped {
member1: TestDropCall,
member2: TestDropCall,
}
#[test]
fn data_is_dropped() {
let drop_called1 = Arc::new(AtomicBool::new(false));
let drop_called2 = Arc::new(AtomicBool::new(false));
{
let gil = Python::acquire_gil();
let py = gil.python();
let data_is_dropped = DataIsDropped {
member1: TestDropCall {
drop_called: Arc::clone(&drop_called1),
},
member2: TestDropCall {
drop_called: Arc::clone(&drop_called2),
},
};
let inst = Py::new(py, data_is_dropped).unwrap();
assert!(!drop_called1.load(Ordering::Relaxed));
assert!(!drop_called2.load(Ordering::Relaxed));
drop(inst);
}
assert!(drop_called1.load(Ordering::Relaxed));
assert!(drop_called2.load(Ordering::Relaxed));
}
#[allow(dead_code)]
#[pyclass]
struct GcIntegration {
self_ref: PyObject,
dropped: TestDropCall,
}
#[pyproto]
impl PyGCProtocol for GcIntegration {
fn __traverse__(&self, visit: PyVisit) -> Result<(), PyTraverseError> {
visit.call(&self.self_ref)
}
fn __clear__(&mut self) {
let gil = Python::acquire_gil();
self.self_ref = gil.python().None();
}
}
#[test]
fn gc_integration() {
let drop_called = Arc::new(AtomicBool::new(false));
{
let gil = Python::acquire_gil();
let py = gil.python();
let inst = PyCell::new(
py,
GcIntegration {
self_ref: py.None(),
dropped: TestDropCall {
drop_called: Arc::clone(&drop_called),
},
},
)
.unwrap();
let mut borrow = inst.borrow_mut();
borrow.self_ref = inst.to_object(py);
}
let gil = Python::acquire_gil();
let py = gil.python();
py.run("import gc; gc.collect()", None, None).unwrap();
assert!(drop_called.load(Ordering::Relaxed));
}
#[pyclass(gc)]
struct GcIntegration2 {}
#[pyproto]
impl PyGCProtocol for GcIntegration2 {
fn __traverse__(&self, _visit: PyVisit) -> Result<(), PyTraverseError> {
Ok(())
}
fn __clear__(&mut self) {}
}
#[test]
fn gc_integration2() {
let gil = Python::acquire_gil();
let py = gil.python();
let inst = PyCell::new(py, GcIntegration2 {}).unwrap();
py_run!(py, inst, "import gc; assert inst in gc.get_objects()");
}
#[pyclass(weakref, subclass)]
struct WeakRefSupport {}
#[test]
#[cfg_attr(all(Py_LIMITED_API, not(Py_3_9)), ignore)]
fn weakref_support() {
let gil = Python::acquire_gil();
let py = gil.python();
let inst = PyCell::new(py, WeakRefSupport {}).unwrap();
py_run!(
py,
inst,
"import weakref; assert weakref.ref(inst)() is inst"
);
}
// If the base class has weakref support, child class also has weakref.
#[pyclass(extends=WeakRefSupport)]
struct InheritWeakRef {
_value: usize,
}
#[test]
#[cfg_attr(all(Py_LIMITED_API, not(Py_3_9)), ignore)]
fn inherited_weakref() {
let gil = Python::acquire_gil();
let py = gil.python();
let inst = PyCell::new(py, (InheritWeakRef { _value: 0 }, WeakRefSupport {})).unwrap();
py_run!(
py,
inst,
"import weakref; assert weakref.ref(inst)() is inst"
);
}
#[pyclass(subclass)]
struct BaseClassWithDrop {
data: Option<Arc<AtomicBool>>,
}
#[pymethods]
impl BaseClassWithDrop {
#[new]
fn new() -> BaseClassWithDrop {
BaseClassWithDrop { data: None }
}
}
impl Drop for BaseClassWithDrop {
fn drop(&mut self) {
if let Some(data) = &self.data {
data.store(true, Ordering::Relaxed);
}
}
}
#[pyclass(extends = BaseClassWithDrop)]
struct SubClassWithDrop {
data: Option<Arc<AtomicBool>>,
}
#[pymethods]
impl SubClassWithDrop {
#[new]
fn new() -> (Self, BaseClassWithDrop) {
(
SubClassWithDrop { data: None },
BaseClassWithDrop { data: None },
)
}
}
impl Drop for SubClassWithDrop {
fn drop(&mut self) {
if let Some(data) = &self.data {
data.store(true, Ordering::Relaxed);
}
}
}
#[test]
fn inheritance_with_new_methods_with_drop() {
let drop_called1 = Arc::new(AtomicBool::new(false));
let drop_called2 = Arc::new(AtomicBool::new(false));
{
let gil = Python::acquire_gil();
let py = gil.python();
let _typebase = py.get_type::<BaseClassWithDrop>();
let typeobj = py.get_type::<SubClassWithDrop>();
let inst = typeobj.call((), None).unwrap();
let obj: &PyCell<SubClassWithDrop> = inst.try_into().unwrap();
let mut obj_ref_mut = obj.borrow_mut();
obj_ref_mut.data = Some(Arc::clone(&drop_called1));
let base: &mut BaseClassWithDrop = obj_ref_mut.as_mut();
base.data = Some(Arc::clone(&drop_called2));
}
assert!(drop_called1.load(Ordering::Relaxed));
assert!(drop_called2.load(Ordering::Relaxed));
}
#[pyclass(gc)]
struct TraversableClass {
traversed: AtomicBool,
}
impl TraversableClass {
fn new() -> Self {
Self {
traversed: AtomicBool::new(false),
}
}
}
#[pyproto]
impl PyGCProtocol for TraversableClass {
fn __clear__(&mut self) {}
fn __traverse__(&self, _visit: PyVisit) -> Result<(), PyTraverseError> {
self.traversed.store(true, Ordering::Relaxed);
Ok(())
}
}
unsafe fn get_type_traverse(tp: *mut pyo3::ffi::PyTypeObject) -> Option<pyo3::ffi::traverseproc> {
std::mem::transmute(pyo3::ffi::PyType_GetSlot(tp, pyo3::ffi::Py_tp_traverse))
}
#[test]
fn gc_during_borrow() {
let gil = Python::acquire_gil();
let py = gil.python();
unsafe {
// declare a dummy visitor function
extern "C" fn novisit(
_object: *mut pyo3::ffi::PyObject,
_arg: *mut core::ffi::c_void,
) -> std::os::raw::c_int {
0
}
// get the traverse function
let ty = TraversableClass::type_object(py).as_type_ptr();
let traverse = get_type_traverse(ty).unwrap();
// create an object and check that traversing it works normally
// when it's not borrowed
let cell = PyCell::new(py, TraversableClass::new()).unwrap();
let obj = cell.to_object(py);
assert!(!cell.borrow().traversed.load(Ordering::Relaxed));
traverse(obj.as_ptr(), novisit, std::ptr::null_mut());
assert!(cell.borrow().traversed.load(Ordering::Relaxed));
// create an object and check that it is not traversed if the GC
// is invoked while it is already borrowed mutably
let cell2 = PyCell::new(py, TraversableClass::new()).unwrap();
let obj2 = cell2.to_object(py);
let guard = cell2.borrow_mut();
assert!(!guard.traversed.load(Ordering::Relaxed));
traverse(obj2.as_ptr(), novisit, std::ptr::null_mut());
assert!(!guard.traversed.load(Ordering::Relaxed));
drop(guard);
}
}