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use crate::conversion::PyTryFrom;
use crate::err::{self, PyDowncastError, PyErr, PyResult};
use crate::gil;
use crate::pycell::{PyBorrowError, PyBorrowMutError, PyCell};
use crate::pyclass::boolean_struct::{False, True};
use crate::types::any::PyAnyMethods;
use crate::types::{PyDict, PyString, PyTuple};
use crate::{
ffi, AsPyPointer, FromPyObject, IntoPy, PyAny, PyClass, PyClassInitializer, PyRef, PyRefMut,
PyTypeInfo, Python, ToPyObject,
};
use std::marker::PhantomData;
use std::mem::{self, ManuallyDrop};
use std::ops::Deref;
use std::ptr::NonNull;
/// Types that are built into the Python interpreter.
///
/// PyO3 is designed in a way that all references to those types are bound
/// to the GIL, which is why you can get a token from all references of those
/// types.
///
/// # Safety
///
/// This trait must only be implemented for types which cannot be accessed without the GIL.
pub unsafe trait PyNativeType: Sized {
/// Returns a GIL marker constrained to the lifetime of this type.
#[inline]
fn py(&self) -> Python<'_> {
unsafe { Python::assume_gil_acquired() }
}
/// Cast `&PyAny` to `&Self` without no type checking.
///
/// # Safety
///
/// `obj` must have the same layout as `*const ffi::PyObject` and must be
/// an instance of a type corresponding to `Self`.
unsafe fn unchecked_downcast(obj: &PyAny) -> &Self {
&*(obj.as_ptr() as *const Self)
}
}
/// A GIL-attached equivalent to `Py`.
#[repr(transparent)]
pub(crate) struct Py2<'py, T>(Python<'py>, ManuallyDrop<Py<T>>);
impl<'py> Py2<'py, PyAny> {
/// Constructs a new Py2 from a pointer. Panics if ptr is null.
pub(crate) unsafe fn from_owned_ptr(py: Python<'py>, ptr: *mut ffi::PyObject) -> Self {
Self(py, ManuallyDrop::new(Py::from_owned_ptr(py, ptr)))
}
// /// Constructs a new Py2 from a pointer. Returns None if ptr is null.
// ///
// /// Safety: ptr must be a valid pointer to a Python object, or NULL.
// pub unsafe fn from_owned_ptr_or_opt(py: Python<'py>, ptr: *mut ffi::PyObject) -> Option<Self> {
// Py::from_owned_ptr_or_opt(py, ptr).map(|obj| Self(py, ManuallyDrop::new(obj)))
// }
/// Constructs a new Py2 from a pointer. Returns error if ptr is null.
pub(crate) unsafe fn from_owned_ptr_or_err(
py: Python<'py>,
ptr: *mut ffi::PyObject,
) -> PyResult<Self> {
Py::from_owned_ptr_or_err(py, ptr).map(|obj| Self(py, ManuallyDrop::new(obj)))
}
}
impl<'py, T> Py2<'py, T> {
/// Helper to cast to Py2<'py, PyAny>
pub(crate) fn as_any(&self) -> &Py2<'py, PyAny> {
// Safety: all Py2<T> have the same memory layout, and all Py2<T> are valid Py2<PyAny>
unsafe { std::mem::transmute(self) }
}
}
impl<'py, T> std::fmt::Debug for Py2<'py, T> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
let any = self.as_any();
python_format(any, any.repr(), f)
}
}
impl<'py, T> std::fmt::Display for Py2<'py, T> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
let any = self.as_any();
python_format(any, any.str(), f)
}
}
fn python_format(
any: &Py2<'_, PyAny>,
format_result: PyResult<Py2<'_, PyString>>,
f: &mut std::fmt::Formatter<'_>,
) -> Result<(), std::fmt::Error> {
match format_result {
Result::Ok(s) => return f.write_str(&s.as_gil_ref().to_string_lossy()),
Result::Err(err) => {
err.write_unraisable(any.py(), std::option::Option::Some(any.as_gil_ref()))
}
}
match any.get_type().name() {
Result::Ok(name) => std::write!(f, "<unprintable {} object>", name),
Result::Err(_err) => f.write_str("<unprintable object>"),
}
}
impl<'py, T> Deref for Py2<'py, T>
where
T: AsRef<PyAny>,
{
type Target = Py2<'py, PyAny>;
#[inline]
fn deref(&self) -> &Py2<'py, PyAny> {
self.as_any()
}
}
impl<'py, T> AsRef<Py2<'py, PyAny>> for Py2<'py, T>
where
T: AsRef<PyAny>,
{
fn as_ref(&self) -> &Py2<'py, PyAny> {
self.as_any()
}
}
impl<T> Clone for Py2<'_, T> {
fn clone(&self) -> Self {
Self(self.0, ManuallyDrop::new(self.1.clone_ref(self.0)))
}
}
impl<T> Drop for Py2<'_, T> {
fn drop(&mut self) {
unsafe { ffi::Py_DECREF(self.1.as_ptr()) }
}
}
impl<'py, T> Py2<'py, T> {
/// Returns the GIL token associated with this object.
pub fn py(&self) -> Python<'py> {
self.0
}
/// Returns the raw FFI pointer represented by self.
///
/// # Safety
///
/// Callers are responsible for ensuring that the pointer does not outlive self.
///
/// The reference is borrowed; callers should not decrease the reference count
/// when they are finished with the pointer.
#[inline]
pub fn as_ptr(&self) -> *mut ffi::PyObject {
self.1.as_ptr()
}
/// Returns an owned raw FFI pointer represented by self.
///
/// # Safety
///
/// The reference is owned; when finished the caller should either transfer ownership
/// of the pointer or decrease the reference count (e.g. with [`pyo3::ffi::Py_DecRef`](crate::ffi::Py_DecRef)).
#[inline]
pub fn into_ptr(self) -> *mut ffi::PyObject {
self.into_non_null().as_ptr()
}
/// Internal helper to convert e.g. &'a &'py PyDict to &'a Py2<'py, PyDict> for
/// backwards-compatibility during migration to removal of pool.
#[doc(hidden)] // public and doc(hidden) to use in examples and tests for now
pub fn borrowed_from_gil_ref<'a>(gil_ref: &'a &'py T::AsRefTarget) -> &'a Self
where
T: PyTypeInfo,
{
// Safety: &'py T::AsRefTarget is expected to be a Python pointer,
// so &'a &'py T::AsRefTarget has the same layout as &'a Py2<'py, T>
unsafe { std::mem::transmute(gil_ref) }
}
/// Internal helper to get to pool references for backwards compatibility
#[doc(hidden)] // public and doc(hidden) to use in examples and tests for now
pub fn as_gil_ref(&'py self) -> &'py T::AsRefTarget
where
T: PyTypeInfo,
{
unsafe { self.py().from_borrowed_ptr(self.as_ptr()) }
}
/// Internal helper to get to pool references for backwards compatibility
#[doc(hidden)] // public but hidden, to use for tests for now
pub fn into_gil_ref(self) -> &'py T::AsRefTarget
where
T: PyTypeInfo,
{
unsafe { self.py().from_owned_ptr(self.into_ptr()) }
}
// Internal helper to convert `self` into a `NonNull` which owns the
// Python reference.
pub(crate) fn into_non_null(self) -> NonNull<ffi::PyObject> {
// wrap in ManuallyDrop to avoid running Drop for self and decreasing
// the reference count
ManuallyDrop::new(self).1 .0
}
}
unsafe impl<T> AsPyPointer for Py2<'_, T> {
fn as_ptr(&self) -> *mut ffi::PyObject {
self.1.as_ptr()
}
}
/// A GIL-independent reference to an object allocated on the Python heap.
///
/// This type does not auto-dereference to the inner object because you must prove you hold the GIL to access it.
/// Instead, call one of its methods to access the inner object:
/// - [`Py::as_ref`], to borrow a GIL-bound reference to the contained object.
/// - [`Py::borrow`], [`Py::try_borrow`], [`Py::borrow_mut`], or [`Py::try_borrow_mut`],
/// to get a (mutable) reference to a contained pyclass, using a scheme similar to std's [`RefCell`].
/// See the [`PyCell` guide entry](https://pyo3.rs/latest/class.html#pycell-and-interior-mutability)
/// for more information.
/// - You can call methods directly on `Py` with [`Py::call`], [`Py::call_method`] and friends.
/// These require passing in the [`Python<'py>`](crate::Python) token but are otherwise similar to the corresponding
/// methods on [`PyAny`].
///
/// # Example: Storing Python objects in structs
///
/// As all the native Python objects only appear as references, storing them in structs doesn't work well.
/// For example, this won't compile:
///
/// ```compile_fail
/// # use pyo3::prelude::*;
/// # use pyo3::types::PyDict;
/// #
/// #[pyclass]
/// struct Foo<'py> {
/// inner: &'py PyDict,
/// }
///
/// impl Foo {
/// fn new() -> Foo {
/// let foo = Python::with_gil(|py| {
/// // `py` will only last for this scope.
///
/// // `&PyDict` derives its lifetime from `py` and
/// // so won't be able to outlive this closure.
/// let dict: &PyDict = PyDict::new(py);
///
/// // because `Foo` contains `dict` its lifetime
/// // is now also tied to `py`.
/// Foo { inner: dict }
/// });
/// // Foo is no longer valid.
/// // Returning it from this function is a 💥 compiler error 💥
/// foo
/// }
/// }
/// ```
///
/// [`Py`]`<T>` can be used to get around this by converting `dict` into a GIL-independent reference:
///
/// ```rust
/// use pyo3::prelude::*;
/// use pyo3::types::PyDict;
///
/// #[pyclass]
/// struct Foo {
/// inner: Py<PyDict>,
/// }
///
/// #[pymethods]
/// impl Foo {
/// #[new]
/// fn __new__() -> Foo {
/// Python::with_gil(|py| {
/// let dict: Py<PyDict> = PyDict::new(py).into();
/// Foo { inner: dict }
/// })
/// }
/// }
/// #
/// # fn main() -> PyResult<()> {
/// # Python::with_gil(|py| {
/// # let m = pyo3::types::PyModule::new(py, "test")?;
/// # m.add_class::<Foo>()?;
/// #
/// # let foo: &PyCell<Foo> = m.getattr("Foo")?.call0()?.downcast()?;
/// # let dict = &foo.borrow().inner;
/// # let dict: &PyDict = dict.as_ref(py);
/// #
/// # Ok(())
/// # })
/// # }
/// ```
///
/// This can also be done with other pyclasses:
/// ```rust
/// use pyo3::prelude::*;
///
/// #[pyclass]
/// struct Bar {/* ... */}
///
/// #[pyclass]
/// struct Foo {
/// inner: Py<Bar>,
/// }
///
/// #[pymethods]
/// impl Foo {
/// #[new]
/// fn __new__() -> PyResult<Foo> {
/// Python::with_gil(|py| {
/// let bar: Py<Bar> = Py::new(py, Bar {})?;
/// Ok(Foo { inner: bar })
/// })
/// }
/// }
/// #
/// # fn main() -> PyResult<()> {
/// # Python::with_gil(|py| {
/// # let m = pyo3::types::PyModule::new(py, "test")?;
/// # m.add_class::<Foo>()?;
/// #
/// # let foo: &PyCell<Foo> = m.getattr("Foo")?.call0()?.downcast()?;
/// # let bar = &foo.borrow().inner;
/// # let bar: &Bar = &*bar.borrow(py);
/// #
/// # Ok(())
/// # })
/// # }
/// ```
///
/// # Example: Shared ownership of Python objects
///
/// `Py<T>` can be used to share ownership of a Python object, similar to std's [`Rc`]`<T>`.
/// As with [`Rc`]`<T>`, cloning it increases its reference count rather than duplicating
/// the underlying object.
///
/// This can be done using either [`Py::clone_ref`] or [`Py`]`<T>`'s [`Clone`] trait implementation.
/// [`Py::clone_ref`] will be faster if you happen to be already holding the GIL.
///
/// ```rust
/// use pyo3::prelude::*;
/// use pyo3::types::PyDict;
///
/// # fn main() {
/// Python::with_gil(|py| {
/// let first: Py<PyDict> = PyDict::new(py).into();
///
/// // All of these are valid syntax
/// let second = Py::clone_ref(&first, py);
/// let third = first.clone_ref(py);
/// let fourth = Py::clone(&first);
/// let fifth = first.clone();
///
/// // Disposing of our original `Py<PyDict>` just decrements the reference count.
/// drop(first);
///
/// // They all point to the same object
/// assert!(second.is(&third));
/// assert!(fourth.is(&fifth));
/// assert!(second.is(&fourth));
/// });
/// # }
/// ```
///
/// # Preventing reference cycles
///
/// It is easy to accidentally create reference cycles using [`Py`]`<T>`.
/// The Python interpreter can break these reference cycles within pyclasses if they
/// [integrate with the garbage collector][gc]. If your pyclass contains other Python
/// objects you should implement it to avoid leaking memory.
///
/// # A note on Python reference counts
///
/// Dropping a [`Py`]`<T>` will eventually decrease Python's reference count
/// of the pointed-to variable, allowing Python's garbage collector to free
/// the associated memory, but this may not happen immediately. This is
/// because a [`Py`]`<T>` can be dropped at any time, but the Python reference
/// count can only be modified when the GIL is held.
///
/// If a [`Py`]`<T>` is dropped while its thread happens to be holding the
/// GIL then the Python reference count will be decreased immediately.
/// Otherwise, the reference count will be decreased the next time the GIL is
/// reacquired.
///
/// # A note on `Send` and `Sync`
///
/// Accessing this object is threadsafe, since any access to its API requires a [`Python<'py>`](crate::Python) token.
/// As you can only get this by acquiring the GIL, `Py<...>` "implements [`Send`] and [`Sync`].
///
/// [`Rc`]: std::rc::Rc
/// [`RefCell`]: std::cell::RefCell
/// [gc]: https://pyo3.rs/main/class/protocols.html#garbage-collector-integration
#[repr(transparent)]
pub struct Py<T>(NonNull<ffi::PyObject>, PhantomData<T>);
// The inner value is only accessed through ways that require proving the gil is held
#[cfg(feature = "nightly")]
unsafe impl<T> crate::marker::Ungil for Py<T> {}
unsafe impl<T> Send for Py<T> {}
unsafe impl<T> Sync for Py<T> {}
impl<T> Py<T>
where
T: PyClass,
{
/// Creates a new instance `Py<T>` of a `#[pyclass]` on the Python heap.
///
/// # Examples
///
/// ```rust
/// use pyo3::prelude::*;
///
/// #[pyclass]
/// struct Foo {/* fields omitted */}
///
/// # fn main() -> PyResult<()> {
/// Python::with_gil(|py| -> PyResult<Py<Foo>> {
/// let foo: Py<Foo> = Py::new(py, Foo {})?;
/// Ok(foo)
/// })?;
/// # Ok(())
/// # }
/// ```
pub fn new(py: Python<'_>, value: impl Into<PyClassInitializer<T>>) -> PyResult<Py<T>> {
let initializer = value.into();
let obj = initializer.create_cell(py)?;
let ob = unsafe { Py::from_owned_ptr(py, obj as _) };
Ok(ob)
}
}
impl<T> Py<T>
where
T: PyTypeInfo,
{
/// Borrows a GIL-bound reference to the contained `T`.
///
/// By binding to the GIL lifetime, this allows the GIL-bound reference to not require
/// [`Python<'py>`](crate::Python) for any of its methods, which makes calling methods
/// on it more ergonomic.
///
/// For native types, this reference is `&T`. For pyclasses, this is `&PyCell<T>`.
///
/// Note that the lifetime of the returned reference is the shortest of `&self` and
/// [`Python<'py>`](crate::Python).
/// Consider using [`Py::into_ref`] instead if this poses a problem.
///
/// # Examples
///
/// Get access to `&PyList` from `Py<PyList>`:
///
/// ```
/// # use pyo3::prelude::*;
/// # use pyo3::types::PyList;
/// #
/// Python::with_gil(|py| {
/// let list: Py<PyList> = PyList::empty(py).into();
/// // FIXME as_ref() no longer makes sense with new Py API, remove this doc
/// // let list: &PyList = list.as_ref(py);
/// // assert_eq!(list.len(), 0);
/// });
/// ```
///
/// Get access to `&PyCell<MyClass>` from `Py<MyClass>`:
///
/// ```
/// # use pyo3::prelude::*;
/// #
/// #[pyclass]
/// struct MyClass {}
///
/// Python::with_gil(|py| {
/// let my_class: Py<MyClass> = Py::new(py, MyClass {}).unwrap();
/// let my_class_cell: &PyCell<MyClass> = my_class.as_ref(py);
/// assert!(my_class_cell.try_borrow().is_ok());
/// });
/// ```
pub fn as_ref<'py>(&'py self, _py: Python<'py>) -> &'py T::AsRefTarget {
let any = self.as_ptr() as *const PyAny;
unsafe { PyNativeType::unchecked_downcast(&*any) }
}
/// Borrows a GIL-bound reference to the contained `T` independently of the lifetime of `T`.
///
/// This method is similar to [`as_ref`](#method.as_ref) but consumes `self` and registers the
/// Python object reference in PyO3's object storage. The reference count for the Python
/// object will not be decreased until the GIL lifetime ends.
///
/// You should prefer using [`as_ref`](#method.as_ref) if you can as it'll have less overhead.
///
/// # Examples
///
/// [`Py::as_ref`]'s lifetime limitation forbids creating a function that references a
/// variable created inside the function.
///
/// ```rust,compile_fail
/// # use pyo3::prelude::*;
/// #
/// fn new_py_any<'py>(py: Python<'py>, value: impl IntoPy<Py<PyAny>>) -> &'py PyAny {
/// let obj: Py<PyAny> = value.into_py(py);
///
/// // The lifetime of the return value of this function is the shortest
/// // of `obj` and `py`. As `obj` is owned by the current function,
/// // Rust won't let the return value escape this function!
/// obj.as_ref(py)
/// }
/// ```
///
/// This can be solved by using [`Py::into_ref`] instead, which does not suffer from this issue.
/// Note that the lifetime of the [`Python<'py>`](crate::Python) token is transferred to
/// the returned reference.
///
/// ```rust
/// # use pyo3::prelude::*;
/// # #[allow(dead_code)] // This is just to show it compiles.
/// fn new_py_any<'py>(py: Python<'py>, value: impl IntoPy<Py<PyAny>>) -> &'py PyAny {
/// let obj: Py<PyAny> = value.into_py(py);
///
/// // This reference's lifetime is determined by `py`'s lifetime.
/// // Because that originates from outside this function,
/// // this return value is allowed.
/// obj.into_ref(py)
/// }
/// ```
pub fn into_ref(self, py: Python<'_>) -> &T::AsRefTarget {
unsafe { py.from_owned_ptr(self.into_ptr()) }
}
}
impl<T> Py<T> {
/// Returns the raw FFI pointer represented by self.
///
/// # Safety
///
/// Callers are responsible for ensuring that the pointer does not outlive self.
///
/// The reference is borrowed; callers should not decrease the reference count
/// when they are finished with the pointer.
#[inline]
pub fn as_ptr(&self) -> *mut ffi::PyObject {
self.0.as_ptr()
}
/// Returns an owned raw FFI pointer represented by self.
///
/// # Safety
///
/// The reference is owned; when finished the caller should either transfer ownership
/// of the pointer or decrease the reference count (e.g. with [`pyo3::ffi::Py_DecRef`](crate::ffi::Py_DecRef)).
#[inline]
pub fn into_ptr(self) -> *mut ffi::PyObject {
let ptr = self.0.as_ptr();
std::mem::forget(self);
ptr
}
}
impl<T> Py<T>
where
T: PyClass,
{
/// Immutably borrows the value `T`.
///
/// This borrow lasts while the returned [`PyRef`] exists.
/// Multiple immutable borrows can be taken out at the same time.
///
/// For frozen classes, the simpler [`get`][Self::get] is available.
///
/// Equivalent to `self.as_ref(py).borrow()` -
/// see [`PyCell::borrow`](crate::pycell::PyCell::borrow).
///
/// # Examples
///
/// ```rust
/// # use pyo3::prelude::*;
/// #
/// #[pyclass]
/// struct Foo {
/// inner: u8,
/// }
///
/// # fn main() -> PyResult<()> {
/// Python::with_gil(|py| -> PyResult<()> {
/// let foo: Py<Foo> = Py::new(py, Foo { inner: 73 })?;
/// let inner: &u8 = &foo.borrow(py).inner;
///
/// assert_eq!(*inner, 73);
/// Ok(())
/// })?;
/// # Ok(())
/// # }
/// ```
///
/// # Panics
///
/// Panics if the value is currently mutably borrowed. For a non-panicking variant, use
/// [`try_borrow`](#method.try_borrow).
pub fn borrow<'py>(&'py self, py: Python<'py>) -> PyRef<'py, T> {
self.as_ref(py).borrow()
}
/// Mutably borrows the value `T`.
///
/// This borrow lasts while the returned [`PyRefMut`] exists.
///
/// Equivalent to `self.as_ref(py).borrow_mut()` -
/// see [`PyCell::borrow_mut`](crate::pycell::PyCell::borrow_mut).
///
/// # Examples
///
/// ```
/// # use pyo3::prelude::*;
/// #
/// #[pyclass]
/// struct Foo {
/// inner: u8,
/// }
///
/// # fn main() -> PyResult<()> {
/// Python::with_gil(|py| -> PyResult<()> {
/// let foo: Py<Foo> = Py::new(py, Foo { inner: 73 })?;
/// foo.borrow_mut(py).inner = 35;
///
/// assert_eq!(foo.borrow(py).inner, 35);
/// Ok(())
/// })?;
/// # Ok(())
/// # }
/// ```
///
/// # Panics
/// Panics if the value is currently borrowed. For a non-panicking variant, use
/// [`try_borrow_mut`](#method.try_borrow_mut).
pub fn borrow_mut<'py>(&'py self, py: Python<'py>) -> PyRefMut<'py, T>
where
T: PyClass<Frozen = False>,
{
self.as_ref(py).borrow_mut()
}
/// Attempts to immutably borrow the value `T`, returning an error if the value is currently mutably borrowed.
///
/// The borrow lasts while the returned [`PyRef`] exists.
///
/// This is the non-panicking variant of [`borrow`](#method.borrow).
///
/// For frozen classes, the simpler [`get`][Self::get] is available.
///
/// Equivalent to `self.as_ref(py).borrow_mut()` -
/// see [`PyCell::try_borrow`](crate::pycell::PyCell::try_borrow).
pub fn try_borrow<'py>(&'py self, py: Python<'py>) -> Result<PyRef<'py, T>, PyBorrowError> {
self.as_ref(py).try_borrow()
}
/// Attempts to mutably borrow the value `T`, returning an error if the value is currently borrowed.
///
/// The borrow lasts while the returned [`PyRefMut`] exists.
///
/// This is the non-panicking variant of [`borrow_mut`](#method.borrow_mut).
///
/// Equivalent to `self.as_ref(py).try_borrow_mut()` -
/// see [`PyCell::try_borrow_mut`](crate::pycell::PyCell::try_borrow_mut).
pub fn try_borrow_mut<'py>(
&'py self,
py: Python<'py>,
) -> Result<PyRefMut<'py, T>, PyBorrowMutError>
where
T: PyClass<Frozen = False>,
{
self.as_ref(py).try_borrow_mut()
}
/// Provide an immutable borrow of the value `T` without acquiring the GIL.
///
/// This is available if the class is [`frozen`][macro@crate::pyclass] and [`Sync`].
///
/// # Examples
///
/// ```
/// use std::sync::atomic::{AtomicUsize, Ordering};
/// # use pyo3::prelude::*;
///
/// #[pyclass(frozen)]
/// struct FrozenCounter {
/// value: AtomicUsize,
/// }
///
/// let cell = Python::with_gil(|py| {
/// let counter = FrozenCounter { value: AtomicUsize::new(0) };
///
/// Py::new(py, counter).unwrap()
/// });
///
/// cell.get().value.fetch_add(1, Ordering::Relaxed);
/// ```
pub fn get(&self) -> &T
where
T: PyClass<Frozen = True> + Sync,
{
let any = self.as_ptr() as *const PyAny;
// SAFETY: The class itself is frozen and `Sync` and we do not access anything but `cell.contents.value`.
unsafe {
let cell: &PyCell<T> = PyNativeType::unchecked_downcast(&*any);
&*cell.get_ptr()
}
}
}
impl<T> Py<T> {
/// Attaches this `Py` to the given Python context, allowing access to further Python APIs.
pub(crate) fn attach<'py>(&self, _py: Python<'py>) -> &Py2<'py, T> {
// Safety: `Py2` has the same layout as `Py`
unsafe { &*(self as *const Py<T>).cast() }
}
/// Same as `attach` but takes ownership of `self`.
pub(crate) fn attach_into(self, py: Python<'_>) -> Py2<'_, T> {
Py2(py, ManuallyDrop::new(self))
}
/// Returns whether `self` and `other` point to the same object. To compare
/// the equality of two objects (the `==` operator), use [`eq`](PyAny::eq).
///
/// This is equivalent to the Python expression `self is other`.
#[inline]
pub fn is<U: AsPyPointer>(&self, o: &U) -> bool {
self.as_ptr() == o.as_ptr()
}
/// Gets the reference count of the `ffi::PyObject` pointer.
#[inline]
pub fn get_refcnt(&self, _py: Python<'_>) -> isize {
unsafe { ffi::Py_REFCNT(self.0.as_ptr()) }
}
/// Makes a clone of `self`.
///
/// This creates another pointer to the same object, increasing its reference count.
///
/// You should prefer using this method over [`Clone`] if you happen to be holding the GIL already.
///
/// # Examples
///
/// ```rust
/// use pyo3::prelude::*;
/// use pyo3::types::PyDict;
///
/// # fn main() {
/// Python::with_gil(|py| {
/// let first: Py<PyDict> = PyDict::new(py).into();
/// let second = Py::clone_ref(&first, py);
///
/// // Both point to the same object
/// assert!(first.is(&second));
/// });
/// # }
/// ```
#[inline]
pub fn clone_ref(&self, py: Python<'_>) -> Py<T> {
unsafe { Py::from_borrowed_ptr(py, self.0.as_ptr()) }
}
/// Returns whether the object is considered to be None.
///
/// This is equivalent to the Python expression `self is None`.
pub fn is_none(&self, _py: Python<'_>) -> bool {
unsafe { ffi::Py_None() == self.as_ptr() }
}
/// Returns whether the object is Ellipsis, e.g. `...`.
///
/// This is equivalent to the Python expression `self is ...`.
#[deprecated(since = "0.20.0", note = "use `.is(py.Ellipsis())` instead")]
pub fn is_ellipsis(&self) -> bool {
unsafe { ffi::Py_Ellipsis() == self.as_ptr() }
}
/// Returns whether the object is considered to be true.
///
/// This is equivalent to the Python expression `bool(self)`.
pub fn is_true(&self, py: Python<'_>) -> PyResult<bool> {
let v = unsafe { ffi::PyObject_IsTrue(self.as_ptr()) };
err::error_on_minusone(py, v)?;
Ok(v != 0)
}
/// Extracts some type from the Python object.
///
/// This is a wrapper function around `FromPyObject::extract()`.
pub fn extract<'p, D>(&'p self, py: Python<'p>) -> PyResult<D>
where
D: FromPyObject<'p>,
{
FromPyObject::extract(unsafe { py.from_borrowed_ptr(self.as_ptr()) })
}
/// Retrieves an attribute value.
///
/// This is equivalent to the Python expression `self.attr_name`.
///
/// If calling this method becomes performance-critical, the [`intern!`](crate::intern) macro
/// can be used to intern `attr_name`, thereby avoiding repeated temporary allocations of
/// Python strings.
///
/// # Example: `intern!`ing the attribute name
///
/// ```
/// # use pyo3::{intern, pyfunction, types::PyModule, IntoPy, Py, Python, PyObject, PyResult};
/// #
/// #[pyfunction]
/// fn version(sys: Py<PyModule>, py: Python<'_>) -> PyResult<PyObject> {
/// sys.getattr(py, intern!(py, "version"))
/// }
/// #
/// # Python::with_gil(|py| {
/// # let sys = py.import("sys").unwrap().into_py(py);
/// # version(sys, py).unwrap();
/// # });
/// ```
pub fn getattr<N>(&self, py: Python<'_>, attr_name: N) -> PyResult<PyObject>
where
N: IntoPy<Py<PyString>>,
{
self.attach(py).as_any().getattr(attr_name).map(Into::into)
}
/// Sets an attribute value.
///
/// This is equivalent to the Python expression `self.attr_name = value`.
///
/// To avoid repeated temporary allocations of Python strings, the [`intern!`](crate::intern)
/// macro can be used to intern `attr_name`.
///
/// # Example: `intern!`ing the attribute name
///
/// ```
/// # use pyo3::{intern, pyfunction, types::PyModule, IntoPy, PyObject, Python, PyResult};
/// #
/// #[pyfunction]
/// fn set_answer(ob: PyObject, py: Python<'_>) -> PyResult<()> {
/// ob.setattr(py, intern!(py, "answer"), 42)
/// }
/// #
/// # Python::with_gil(|py| {
/// # let ob = PyModule::new(py, "empty").unwrap().into_py(py);
/// # set_answer(ob, py).unwrap();
/// # });
/// ```
pub fn setattr<N, V>(&self, py: Python<'_>, attr_name: N, value: V) -> PyResult<()>
where
N: IntoPy<Py<PyString>>,
V: IntoPy<Py<PyAny>>,
{
self.attach(py)
.as_any()
.setattr(attr_name, value.into_py(py).attach_into(py))
}
/// Calls the object.
///
/// This is equivalent to the Python expression `self(*args, **kwargs)`.
pub fn call(
&self,
py: Python<'_>,
args: impl IntoPy<Py<PyTuple>>,
kwargs: Option<&PyDict>,
) -> PyResult<PyObject> {
self.attach(py).as_any().call(args, kwargs).map(Into::into)
}
/// Calls the object with only positional arguments.
///
/// This is equivalent to the Python expression `self(*args)`.
pub fn call1(&self, py: Python<'_>, args: impl IntoPy<Py<PyTuple>>) -> PyResult<PyObject> {
self.attach(py).as_any().call1(args).map(Into::into)
}
/// Calls the object without arguments.
///
/// This is equivalent to the Python expression `self()`.
pub fn call0(&self, py: Python<'_>) -> PyResult<PyObject> {
self.attach(py).as_any().call0().map(Into::into)
}
/// Calls a method on the object.
///
/// This is equivalent to the Python expression `self.name(*args, **kwargs)`.
///
/// To avoid repeated temporary allocations of Python strings, the [`intern!`](crate::intern)
/// macro can be used to intern `name`.
pub fn call_method<N, A>(
&self,
py: Python<'_>,
name: N,
args: A,
kwargs: Option<&PyDict>,
) -> PyResult<PyObject>
where
N: IntoPy<Py<PyString>>,
A: IntoPy<Py<PyTuple>>,
{
self.attach(py)
.as_any()
.call_method(name, args, kwargs)
.map(Into::into)
}
/// Calls a method on the object with only positional arguments.
///
/// This is equivalent to the Python expression `self.name(*args)`.
///
/// To avoid repeated temporary allocations of Python strings, the [`intern!`](crate::intern)
/// macro can be used to intern `name`.
pub fn call_method1<N, A>(&self, py: Python<'_>, name: N, args: A) -> PyResult<PyObject>
where
N: IntoPy<Py<PyString>>,
A: IntoPy<Py<PyTuple>>,
{
self.attach(py)
.as_any()
.call_method1(name, args)
.map(Into::into)
}
/// Calls a method on the object with no arguments.
///
/// This is equivalent to the Python expression `self.name()`.
///
/// To avoid repeated temporary allocations of Python strings, the [`intern!`](crate::intern)
/// macro can be used to intern `name`.
pub fn call_method0<N>(&self, py: Python<'_>, name: N) -> PyResult<PyObject>
where
N: IntoPy<Py<PyString>>,
{
self.attach(py).as_any().call_method0(name).map(Into::into)
}
/// Create a `Py<T>` instance by taking ownership of the given FFI pointer.
///
/// # Safety
/// `ptr` must be a pointer to a Python object of type T.
///
/// Callers must own the object referred to by `ptr`, as this function
/// implicitly takes ownership of that object.
///
/// # Panics
/// Panics if `ptr` is null.
#[inline]
pub unsafe fn from_owned_ptr(py: Python<'_>, ptr: *mut ffi::PyObject) -> Py<T> {
match NonNull::new(ptr) {
Some(nonnull_ptr) => Py(nonnull_ptr, PhantomData),
None => crate::err::panic_after_error(py),
}
}
/// Create a `Py<T>` instance by taking ownership of the given FFI pointer.
///
/// If `ptr` is null then the current Python exception is fetched as a [`PyErr`].
///
/// # Safety
/// If non-null, `ptr` must be a pointer to a Python object of type T.
#[inline]
pub unsafe fn from_owned_ptr_or_err(
py: Python<'_>,
ptr: *mut ffi::PyObject,
) -> PyResult<Py<T>> {
match NonNull::new(ptr) {
Some(nonnull_ptr) => Ok(Py(nonnull_ptr, PhantomData)),
None => Err(PyErr::fetch(py)),
}
}
/// Create a `Py<T>` instance by taking ownership of the given FFI pointer.
///
/// If `ptr` is null then `None` is returned.
///
/// # Safety
/// If non-null, `ptr` must be a pointer to a Python object of type T.
#[inline]
pub unsafe fn from_owned_ptr_or_opt(_py: Python<'_>, ptr: *mut ffi::PyObject) -> Option<Self> {
NonNull::new(ptr).map(|nonnull_ptr| Py(nonnull_ptr, PhantomData))
}
/// Create a `Py<T>` instance by creating a new reference from the given FFI pointer.
///
/// # Safety
/// `ptr` must be a pointer to a Python object of type T.
///
/// # Panics
/// Panics if `ptr` is null.
#[inline]
pub unsafe fn from_borrowed_ptr(py: Python<'_>, ptr: *mut ffi::PyObject) -> Py<T> {
match Self::from_borrowed_ptr_or_opt(py, ptr) {
Some(slf) => slf,
None => crate::err::panic_after_error(py),
}
}
/// Create a `Py<T>` instance by creating a new reference from the given FFI pointer.
///
/// If `ptr` is null then the current Python exception is fetched as a `PyErr`.
///
/// # Safety
/// `ptr` must be a pointer to a Python object of type T.
#[inline]
pub unsafe fn from_borrowed_ptr_or_err(
py: Python<'_>,
ptr: *mut ffi::PyObject,
) -> PyResult<Self> {
Self::from_borrowed_ptr_or_opt(py, ptr).ok_or_else(|| PyErr::fetch(py))
}
/// Create a `Py<T>` instance by creating a new reference from the given FFI pointer.
///
/// If `ptr` is null then `None` is returned.
///
/// # Safety
/// `ptr` must be a pointer to a Python object of type T.
#[inline]
pub unsafe fn from_borrowed_ptr_or_opt(
_py: Python<'_>,
ptr: *mut ffi::PyObject,
) -> Option<Self> {
NonNull::new(ptr).map(|nonnull_ptr| {
ffi::Py_INCREF(ptr);
Py(nonnull_ptr, PhantomData)
})
}
/// For internal conversions.
///
/// # Safety
/// `ptr` must point to a Python object of type T.
#[inline]
unsafe fn from_non_null(ptr: NonNull<ffi::PyObject>) -> Self {
Self(ptr, PhantomData)
}
/// Returns the inner pointer without decreasing the refcount.
#[inline]
fn into_non_null(self) -> NonNull<ffi::PyObject> {
let pointer = self.0;
mem::forget(self);
pointer
}
}
impl<T> ToPyObject for Py<T> {
/// Converts `Py` instance -> PyObject.
fn to_object(&self, py: Python<'_>) -> PyObject {
unsafe { PyObject::from_borrowed_ptr(py, self.as_ptr()) }
}
}
impl<T> IntoPy<PyObject> for Py<T> {
/// Converts a `Py` instance to `PyObject`.
/// Consumes `self` without calling `Py_DECREF()`.
#[inline]
fn into_py(self, _py: Python<'_>) -> PyObject {
unsafe { PyObject::from_non_null(self.into_non_null()) }
}
}
impl<T> IntoPy<PyObject> for &'_ Py<T> {
#[inline]
fn into_py(self, py: Python<'_>) -> PyObject {
self.to_object(py)
}
}
impl<T> ToPyObject for Py2<'_, T> {
/// Converts `Py` instance -> PyObject.
fn to_object(&self, py: Python<'_>) -> PyObject {
unsafe { PyObject::from_borrowed_ptr(py, self.as_ptr()) }
}
}
impl<T> IntoPy<PyObject> for Py2<'_, T> {
/// Converts a `Py` instance to `PyObject`.
/// Consumes `self` without calling `Py_DECREF()`.
#[inline]
fn into_py(self, _py: Python<'_>) -> PyObject {
unsafe { PyObject::from_non_null(self.into_non_null()) }
}
}
impl<T> IntoPy<PyObject> for &Py2<'_, T> {
/// Converts a `Py` instance to `PyObject`.
/// Consumes `self` without calling `Py_DECREF()`.
#[inline]
fn into_py(self, _py: Python<'_>) -> PyObject {
unsafe { PyObject::from_non_null(self.clone().into_non_null()) }
}
}
unsafe impl<T> crate::AsPyPointer for Py<T> {
/// Gets the underlying FFI pointer, returns a borrowed pointer.
#[inline]
fn as_ptr(&self) -> *mut ffi::PyObject {
self.0.as_ptr()
}
}
impl std::convert::From<&'_ PyAny> for PyObject {
fn from(obj: &PyAny) -> Self {
unsafe { Py::from_borrowed_ptr(obj.py(), obj.as_ptr()) }
}
}
impl<T> std::convert::From<&'_ T> for PyObject
where
T: PyNativeType + AsRef<PyAny>,
{
fn from(obj: &T) -> Self {
unsafe { Py::from_borrowed_ptr(obj.py(), obj.as_ref().as_ptr()) }
}
}
impl<T> std::convert::From<Py<T>> for PyObject
where
T: AsRef<PyAny>,
{
#[inline]
fn from(other: Py<T>) -> Self {
unsafe { Self::from_non_null(other.into_non_null()) }
}
}
impl<T> std::convert::From<Py2<'_, T>> for PyObject
where
T: AsRef<PyAny>,
{
#[inline]
fn from(other: Py2<'_, T>) -> Self {
let py = other.py();
other.into_py(py)
}
}
impl<T> std::convert::From<Py2<'_, T>> for Py<T> {
#[inline]
fn from(other: Py2<'_, T>) -> Self {
unsafe { Self::from_non_null(other.into_non_null()) }
}
}
// `&PyCell<T>` can be converted to `Py<T>`
impl<T> std::convert::From<&PyCell<T>> for Py<T>
where
T: PyClass,
{
fn from(cell: &PyCell<T>) -> Self {
unsafe { Py::from_borrowed_ptr(cell.py(), cell.as_ptr()) }
}
}
impl<'a, T> std::convert::From<PyRef<'a, T>> for Py<T>
where
T: PyClass,
{
fn from(pyref: PyRef<'a, T>) -> Self {
unsafe { Py::from_borrowed_ptr(pyref.py(), pyref.as_ptr()) }
}
}
impl<'a, T> std::convert::From<PyRefMut<'a, T>> for Py<T>
where
T: PyClass<Frozen = False>,
{
fn from(pyref: PyRefMut<'a, T>) -> Self {
unsafe { Py::from_borrowed_ptr(pyref.py(), pyref.as_ptr()) }
}
}
/// If the GIL is held this increments `self`'s reference count.
/// Otherwise this registers the [`Py`]`<T>` instance to have its reference count
/// incremented the next time PyO3 acquires the GIL.
impl<T> Clone for Py<T> {
fn clone(&self) -> Self {
unsafe {
gil::register_incref(self.0);
}
Self(self.0, PhantomData)
}
}
/// Dropping a `Py` instance decrements the reference count on the object by 1.
impl<T> Drop for Py<T> {
fn drop(&mut self) {
unsafe {
gil::register_decref(self.0);
}
}
}
impl<'a, T> FromPyObject<'a> for Py<T>
where
T: PyTypeInfo,
&'a T::AsRefTarget: FromPyObject<'a>,
T::AsRefTarget: 'a + AsPyPointer,
{
/// Extracts `Self` from the source `PyObject`.
fn extract(ob: &'a PyAny) -> PyResult<Self> {
unsafe {
ob.extract::<&T::AsRefTarget>()
.map(|val| Py::from_borrowed_ptr(ob.py(), val.as_ptr()))
}
}
}
impl<'a, T> FromPyObject<'a> for Py2<'a, T>
where
T: PyTypeInfo,
{
/// Extracts `Self` from the source `PyObject`.
fn extract(ob: &'a PyAny) -> PyResult<Self> {
Py2::<PyAny>::borrowed_from_gil_ref(&ob)
.downcast()
.map(Clone::clone)
.map_err(Into::into)
}
}
/// `Py<T>` can be used as an error when T is an Error.
///
/// However for GIL lifetime reasons, cause() cannot be implemented for `Py<T>`.
/// Use .as_ref() to get the GIL-scoped error if you need to inspect the cause.
impl<T> std::error::Error for Py<T>
where
T: std::error::Error + PyTypeInfo,
T::AsRefTarget: std::fmt::Display,
{
}
impl<T> std::fmt::Display for Py<T>
where
T: PyTypeInfo,
T::AsRefTarget: std::fmt::Display,
{
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
Python::with_gil(|py| std::fmt::Display::fmt(self.as_ref(py), f))
}
}
impl<T> std::fmt::Debug for Py<T> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.debug_tuple("Py").field(&self.0.as_ptr()).finish()
}
}
/// A commonly-used alias for `Py<PyAny>`.
///
/// This is an owned reference a Python object without any type information. This value can also be
/// safely sent between threads.
///
/// See the documentation for [`Py`](struct.Py.html).
pub type PyObject = Py<PyAny>;
impl PyObject {
/// Downcast this `PyObject` to a concrete Python type or pyclass.
///
/// Note that you can often avoid downcasting yourself by just specifying
/// the desired type in function or method signatures.
/// However, manual downcasting is sometimes necessary.
///
/// For extracting a Rust-only type, see [`Py::extract`](struct.Py.html#method.extract).
///
/// # Example: Downcasting to a specific Python object
///
/// ```rust
/// use pyo3::prelude::*;
/// use pyo3::types::{PyDict, PyList};
///
/// Python::with_gil(|py| {
/// let any: PyObject = PyDict::new(py).into();
///
/// assert!(any.downcast::<PyDict>(py).is_ok());
/// assert!(any.downcast::<PyList>(py).is_err());
/// });
/// ```
///
/// # Example: Getting a reference to a pyclass
///
/// This is useful if you want to mutate a `PyObject` that
/// might actually be a pyclass.
///
/// ```rust
/// # fn main() -> Result<(), pyo3::PyErr> {
/// use pyo3::prelude::*;
///
/// #[pyclass]
/// struct Class {
/// i: i32,
/// }
///
/// Python::with_gil(|py| {
/// let class: PyObject = Py::new(py, Class { i: 0 }).unwrap().into_py(py);
///
/// let class_cell: &PyCell<Class> = class.downcast(py)?;
///
/// class_cell.borrow_mut().i += 1;
///
/// // Alternatively you can get a `PyRefMut` directly
/// let class_ref: PyRefMut<'_, Class> = class.extract(py)?;
/// assert_eq!(class_ref.i, 1);
/// Ok(())
/// })
/// # }
/// ```
#[inline]
pub fn downcast<'p, T>(&'p self, py: Python<'p>) -> Result<&T, PyDowncastError<'_>>
where
T: PyTryFrom<'p>,
{
<T as PyTryFrom<'_>>::try_from(self.as_ref(py))
}
/// Casts the PyObject to a concrete Python object type without checking validity.
///
/// # Safety
///
/// Callers must ensure that the type is valid or risk type confusion.
#[inline]
pub unsafe fn downcast_unchecked<'p, T>(&'p self, py: Python<'p>) -> &T
where
T: PyTryFrom<'p>,
{
<T as PyTryFrom<'_>>::try_from_unchecked(self.as_ref(py))
}
}
#[cfg(test)]
mod tests {
use super::{Py, Py2, PyObject};
use crate::types::{PyDict, PyString};
use crate::{PyAny, PyResult, Python, ToPyObject};
#[test]
fn test_call0() {
Python::with_gil(|py| {
let obj = py.get_type::<PyDict>().to_object(py);
assert_eq!(
obj.call0(py)
.unwrap()
.as_ref(py)
.repr()
.unwrap()
.to_string_lossy(),
"{}"
);
})
}
#[test]
fn test_call_for_non_existing_method() {
Python::with_gil(|py| {
let obj: PyObject = PyDict::new(py).into();
assert!(obj.call_method0(py, "asdf").is_err());
assert!(obj
.call_method(py, "nonexistent_method", (1,), None)
.is_err());
assert!(obj.call_method0(py, "nonexistent_method").is_err());
assert!(obj.call_method1(py, "nonexistent_method", (1,)).is_err());
});
}
#[test]
fn py_from_dict() {
let dict: Py<PyDict> = Python::with_gil(|py| {
let native = PyDict::new(py);
Py::from(native)
});
assert_eq!(Python::with_gil(|py| dict.get_refcnt(py)), 1);
}
#[test]
fn pyobject_from_py() {
Python::with_gil(|py| {
let dict: Py<PyDict> = PyDict::new(py).into();
let cnt = dict.get_refcnt(py);
let p: PyObject = dict.into();
assert_eq!(p.get_refcnt(py), cnt);
});
}
#[test]
fn attr() -> PyResult<()> {
use crate::types::PyModule;
Python::with_gil(|py| {
const CODE: &str = r#"
class A:
pass
a = A()
"#;
let module = PyModule::from_code(py, CODE, "", "")?;
let instance: Py<PyAny> = module.getattr("a")?.into();
instance.getattr(py, "foo").unwrap_err();
instance.setattr(py, "foo", "bar")?;
assert!(instance
.getattr(py, "foo")?
.as_ref(py)
.eq(PyString::new(py, "bar"))?);
instance.getattr(py, "foo")?;
Ok(())
})
}
#[test]
fn pystring_attr() -> PyResult<()> {
use crate::types::PyModule;
Python::with_gil(|py| {
const CODE: &str = r#"
class A:
pass
a = A()
"#;
let module = PyModule::from_code(py, CODE, "", "")?;
let instance: Py<PyAny> = module.getattr("a")?.into();
let foo = crate::intern!(py, "foo");
let bar = crate::intern!(py, "bar");
instance.getattr(py, foo).unwrap_err();
instance.setattr(py, foo, bar)?;
assert!(instance.getattr(py, foo)?.as_ref(py).eq(bar)?);
Ok(())
})
}
#[test]
fn invalid_attr() -> PyResult<()> {
Python::with_gil(|py| {
let instance: Py<PyAny> = py.eval("object()", None, None)?.into();
instance.getattr(py, "foo").unwrap_err();
// Cannot assign arbitrary attributes to `object`
instance.setattr(py, "foo", "bar").unwrap_err();
Ok(())
})
}
#[test]
fn test_py2_from_py_object() {
Python::with_gil(|py| {
let instance: &PyAny = py.eval("object()", None, None).unwrap();
let ptr = instance.as_ptr();
let instance: Py2<'_, PyAny> = instance.extract().unwrap();
assert_eq!(instance.as_ptr(), ptr);
})
}
#[test]
fn test_py2_into_py_object() {
Python::with_gil(|py| {
let instance: Py2<'_, PyAny> =
Py2::borrowed_from_gil_ref(&py.eval("object()", None, None).unwrap()).clone();
let ptr = instance.as_ptr();
let instance: PyObject = instance.clone().into();
assert_eq!(instance.as_ptr(), ptr);
})
}
#[test]
#[allow(deprecated)]
fn test_is_ellipsis() {
Python::with_gil(|py| {
let v = py
.eval("...", None, None)
.map_err(|e| e.display(py))
.unwrap()
.to_object(py);
assert!(v.is_ellipsis());
let not_ellipsis = 5.to_object(py);
assert!(!not_ellipsis.is_ellipsis());
});
}
#[test]
fn test_debug_fmt() {
Python::with_gil(|py| {
let obj = "hello world".to_object(py).attach_into(py);
assert_eq!(format!("{:?}", obj), "'hello world'");
});
}
#[test]
fn test_display_fmt() {
Python::with_gil(|py| {
let obj = "hello world".to_object(py).attach_into(py);
assert_eq!(format!("{}", obj), "hello world");
});
}
#[cfg(feature = "macros")]
mod using_macros {
use super::*;
#[crate::pyclass]
#[pyo3(crate = "crate")]
struct SomeClass(i32);
#[test]
fn instance_borrow_methods() {
// More detailed tests of the underlying semantics in pycell.rs
Python::with_gil(|py| {
let instance = Py::new(py, SomeClass(0)).unwrap();
assert_eq!(instance.borrow(py).0, 0);
assert_eq!(instance.try_borrow(py).unwrap().0, 0);
assert_eq!(instance.borrow_mut(py).0, 0);
assert_eq!(instance.try_borrow_mut(py).unwrap().0, 0);
instance.borrow_mut(py).0 = 123;
assert_eq!(instance.borrow(py).0, 123);
assert_eq!(instance.try_borrow(py).unwrap().0, 123);
assert_eq!(instance.borrow_mut(py).0, 123);
assert_eq!(instance.try_borrow_mut(py).unwrap().0, 123);
})
}
}
}