Remove IntoPyPointer

guide/src/migration.md

@@ -62,6 +62,10 @@ fn add(a: u64, b: u64) -> u64 {
 }
 ```
 
+### `IntoPyPointer` trait removed
+
+The trait `IntoPyPointer`, which provided the `into_ptr` method on many types, has been removed. `into_ptr` is now available as an inherent method on all types that previously implemented this trait.
+
 ## from 0.18.* to 0.19
 
 ### Access to `Python` inside `__traverse__` implementations are now forbidden

newsfragments/3385.removed.md

@@ -0,0 +1 @@
+Removed `IntoPyPointer` trait, `into_ptr` is now an inherent method on most types representing Python objects

src/conversion.rs

@@ -61,38 +61,6 @@ pub trait AsPyPointer {
     fn as_ptr(&self) -> *mut ffi::PyObject;
 }
 
-/// Returns an owned pointer to a Python object.
-///
-/// The returned pointer will be valid until you decrease its reference count. It may be null
-/// depending on the implementation.
-/// It is your responsibility to decrease the reference count of the pointer to avoid leaking memory.
-///
-/// # Examples
-///
-/// ```rust
-/// use pyo3::prelude::*;
-/// use pyo3::types::PyString;
-/// use pyo3::ffi;
-///
-/// Python::with_gil(|py| {
-///     let s: Py<PyString> = "foo".into_py(py);
-///     let ptr = s.into_ptr();
-///
-///     let is_really_a_pystring = unsafe { ffi::PyUnicode_CheckExact(ptr) };
-///     assert_eq!(is_really_a_pystring, 1);
-///
-///     // Because we took ownership of the pointer,
-///     // we must manually decrement it to avoid leaking memory
-///     unsafe { ffi::Py_DECREF(ptr) };
-/// });
-/// ```
-pub trait IntoPyPointer {
-    /// Returns the underlying FFI pointer as an owned pointer.
-    ///
-    /// If `self` has ownership of the underlying pointer, it will "steal" ownership of it.
-    fn into_ptr(self) -> *mut ffi::PyObject;
-}
-
 /// Convert `None` into a null pointer.
 impl<T> AsPyPointer for Option<T>
 where
@@ -105,26 +73,6 @@ where
     }
 }
 
-/// Convert `None` into a null pointer.
-impl<T> IntoPyPointer for Option<T>
-where
-    T: IntoPyPointer,
-{
-    #[inline]
-    fn into_ptr(self) -> *mut ffi::PyObject {
-        self.map_or_else(std::ptr::null_mut, |t| t.into_ptr())
-    }
-}
-
-impl<'a, T> IntoPyPointer for &'a T
-where
-    T: AsPyPointer,
-{
-    fn into_ptr(self) -> *mut ffi::PyObject {
-        unsafe { ffi::_Py_XNewRef(self.as_ptr()) }
-    }
-}
-
 /// Conversion trait that allows various objects to be converted into `PyObject`.
 pub trait ToPyObject {
     /// Converts self into a Python object.

src/instance.rs

@@ -5,8 +5,8 @@ use crate::pycell::{PyBorrowError, PyBorrowMutError, PyCell};
 use crate::pyclass::boolean_struct::{False, True};
 use crate::types::{PyDict, PyString, PyTuple};
 use crate::{
-    ffi, AsPyPointer, FromPyObject, IntoPy, IntoPyPointer, PyAny, PyClass, PyClassInitializer,
-    PyRef, PyRefMut, PyTypeInfo, Python, ToPyObject,
+    ffi, AsPyPointer, FromPyObject, IntoPy, PyAny, PyClass, PyClassInitializer, PyRef, PyRefMut,
+    PyTypeInfo, Python, ToPyObject,
 };
 use std::marker::PhantomData;
 use std::mem;
@@ -693,7 +693,7 @@ impl<T> Py<T> {
         kwargs: Option<&PyDict>,
     ) -> PyResult<PyObject> {
         let args = args.into_py(py);
-        let kwargs = kwargs.into_ptr();
+        let kwargs = kwargs.map_or(std::ptr::null_mut(), |p| p.into_ptr());
 
         unsafe {
             let ret = PyObject::from_owned_ptr_or_err(
@@ -750,7 +750,7 @@ impl<T> Py<T> {
     {
         let callee = self.getattr(py, name)?;
         let args: Py<PyTuple> = args.into_py(py);
-        let kwargs = kwargs.into_ptr();
+        let kwargs = kwargs.map_or(std::ptr::null_mut(), |p| p.into_ptr());
 
         unsafe {
             let result = PyObject::from_owned_ptr_or_err(
@@ -933,15 +933,6 @@ impl<T> crate::AsPyPointer for Py<T> {
     }
 }
 
-impl<T> IntoPyPointer for Py<T> {
-    /// Gets the underlying FFI pointer, returns a owned pointer.
-    #[inline]
-    #[must_use]
-    fn into_ptr(self) -> *mut ffi::PyObject {
-        self.into_non_null().as_ptr()
-    }
-}
-
 impl<T> std::convert::From<&'_ T> for PyObject
 where
     T: AsPyPointer + PyNativeType,

src/lib.rs

@@ -297,8 +297,7 @@
 //! [`Ungil`]: crate::marker::Ungil
 pub use crate::class::*;
 pub use crate::conversion::{
-    AsPyPointer, FromPyObject, FromPyPointer, IntoPy, IntoPyPointer, PyTryFrom, PyTryInto,
-    ToPyObject,
+    AsPyPointer, FromPyObject, FromPyPointer, IntoPy, PyTryFrom, PyTryInto, ToPyObject,
 };
 pub use crate::err::{PyDowncastError, PyErr, PyErrArguments, PyResult};
 pub use crate::gil::GILPool;

src/prelude.rs

@@ -8,9 +8,7 @@
 //! use pyo3::prelude::*;
 //! ```
 
-pub use crate::conversion::{
-    FromPyObject, IntoPy, IntoPyPointer, PyTryFrom, PyTryInto, ToPyObject,
-};
+pub use crate::conversion::{FromPyObject, IntoPy, PyTryFrom, PyTryInto, ToPyObject};
 pub use crate::err::{PyErr, PyResult};
 pub use crate::instance::{Py, PyObject};
 pub use crate::marker::Python;