From 1b61cb015a498d383c4a9406e2179f3f2849d65e Mon Sep 17 00:00:00 2001
From: David Hewitt <mail@davidhewitt.dev>
Date: Sat, 23 Dec 2023 21:48:04 +0000
Subject: [PATCH 1/2] Add `.as_borrowed()` conversion from gil-refs to
 `Bound<T>`

---
 newsfragments/3692.added.md   |   1 +
 newsfragments/3692.changed.md |   1 +
 src/conversions/chrono.rs     |   7 ++-
 src/err/mod.rs                |   6 +-
 src/instance.rs               |  42 +++++++-------
 src/prelude.rs                |   1 +
 src/types/any.rs              | 100 +++++++++++++++-------------------
 src/types/boolobject.rs       |   6 +-
 src/types/bytearray.rs        |  16 +++---
 src/types/bytes.rs            |   4 +-
 src/types/datetime.rs         |  42 +++++++-------
 src/types/dict.rs             |  32 +++++------
 src/types/float.rs            |   2 +-
 src/types/iterator.rs         |   6 +-
 src/types/list.rs             |  44 ++++++---------
 src/types/mapping.rs          |  31 ++++-------
 src/types/mod.rs              |   3 +-
 src/types/pysuper.rs          |  11 ++--
 src/types/sequence.rs         |  51 +++++++----------
 src/types/string.rs           |  10 ++--
 20 files changed, 185 insertions(+), 231 deletions(-)
 create mode 100644 newsfragments/3692.added.md
 create mode 100644 newsfragments/3692.changed.md

diff --git a/newsfragments/3692.added.md b/newsfragments/3692.added.md
new file mode 100644
index 00000000000..45cdd5aba28
--- /dev/null
+++ b/newsfragments/3692.added.md
@@ -0,0 +1 @@
+Add `PyNativeType::as_bound` to convert "GIL refs" to the new `Bound` smart pointer.
diff --git a/newsfragments/3692.changed.md b/newsfragments/3692.changed.md
new file mode 100644
index 00000000000..9535cbb23db
--- /dev/null
+++ b/newsfragments/3692.changed.md
@@ -0,0 +1 @@
+Include `PyNativeType` in `pyo3::prelude`.
diff --git a/src/conversions/chrono.rs b/src/conversions/chrono.rs
index 83100f8023a..cc0eb73a8ef 100644
--- a/src/conversions/chrono.rs
+++ b/src/conversions/chrono.rs
@@ -42,7 +42,6 @@
 //! }
 //! ```
 use crate::exceptions::{PyTypeError, PyUserWarning, PyValueError};
-use crate::instance::Bound;
 #[cfg(Py_LIMITED_API)]
 use crate::sync::GILOnceCell;
 #[cfg(not(Py_LIMITED_API))]
@@ -56,7 +55,9 @@ use crate::types::{
 };
 #[cfg(Py_LIMITED_API)]
 use crate::{intern, PyDowncastError};
-use crate::{FromPyObject, IntoPy, PyAny, PyErr, PyObject, PyResult, Python, ToPyObject};
+use crate::{
+    FromPyObject, IntoPy, PyAny, PyErr, PyNativeType, PyObject, PyResult, Python, ToPyObject,
+};
 use chrono::offset::{FixedOffset, Utc};
 use chrono::{
     DateTime, Datelike, Duration, NaiveDate, NaiveDateTime, NaiveTime, Offset, TimeZone, Timelike,
@@ -466,7 +467,7 @@ fn warn_truncated_leap_second(obj: &PyAny) {
         "ignored leap-second, `datetime` does not support leap-seconds",
         0,
     ) {
-        e.write_unraisable_bound(py, Some(Bound::borrowed_from_gil_ref(&obj)))
+        e.write_unraisable_bound(py, Some(&obj.as_borrowed()))
     };
 }
 
diff --git a/src/err/mod.rs b/src/err/mod.rs
index c2d47a8f17a..ed719103646 100644
--- a/src/err/mod.rs
+++ b/src/err/mod.rs
@@ -7,7 +7,7 @@ use crate::{
     exceptions::{self, PyBaseException},
     ffi,
 };
-use crate::{IntoPy, Py, PyAny, PyObject, Python, ToPyObject};
+use crate::{IntoPy, Py, PyAny, PyNativeType, PyObject, Python, ToPyObject};
 use std::borrow::Cow;
 use std::cell::UnsafeCell;
 use std::ffi::CString;
@@ -542,7 +542,7 @@ impl PyErr {
     )]
     #[inline]
     pub fn write_unraisable(self, py: Python<'_>, obj: Option<&PyAny>) {
-        self.write_unraisable_bound(py, obj.as_ref().map(Bound::borrowed_from_gil_ref))
+        self.write_unraisable_bound(py, obj.map(PyAny::as_borrowed).as_deref())
     }
 
     /// Reports the error as unraisable.
@@ -821,7 +821,7 @@ impl<'a> std::error::Error for PyDowncastError<'a> {}
 
 impl<'a> std::fmt::Display for PyDowncastError<'a> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
-        display_downcast_error(f, Bound::borrowed_from_gil_ref(&self.from), &self.to)
+        display_downcast_error(f, &self.from.as_borrowed(), &self.to)
     }
 }
 
diff --git a/src/instance.rs b/src/instance.rs
index dae71e671d8..90e672c4fa5 100644
--- a/src/instance.rs
+++ b/src/instance.rs
@@ -28,6 +28,19 @@ pub unsafe trait PyNativeType: Sized {
     /// The form of this which is stored inside a `Py<T>` smart pointer.
     type AsRefSource: HasPyGilRef<AsRefTarget = Self>;
 
+    /// Cast `&self` to a `Borrowed` smart pointer.
+    ///
+    /// `Borrowed<T>` implements `Deref<Target=Bound<T>>`, so can also be used in locations
+    /// where `Bound<T>` is expected.
+    ///
+    /// This is available as a migration tool to adjust code from the deprecated "GIL Refs"
+    /// API to the `Bound` smart pointer API.
+    fn as_borrowed(&self) -> Borrowed<'_, '_, Self::AsRefSource> {
+        // Safety: &'py Self is expected to be a Python pointer,
+        // so has the same layout as Borrowed<'py, 'py, T>
+        unsafe { std::mem::transmute(self) }
+    }
+
     /// Returns a GIL marker constrained to the lifetime of this type.
     #[inline]
     fn py(&self) -> Python<'_> {
@@ -184,18 +197,6 @@ impl<'py, T> Bound<'py, T> {
         self.into_non_null().as_ptr()
     }
 
-    /// Internal helper to convert e.g. &'a &'py PyDict to &'a Bound<'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, U>(gil_ref: &'a &'py U) -> &'a Self
-    where
-        U: PyNativeType<AsRefSource = T>,
-    {
-        // Safety: &'py T::AsRefTarget is expected to be a Python pointer,
-        // so &'a &'py T::AsRefTarget has the same layout as &'a Bound<'py, T>
-        unsafe { std::mem::transmute(gil_ref) }
-    }
-
     /// Casts this `Bound<T>` as the corresponding "GIL Ref" type.
     ///
     /// This is a helper to be used for migration from the deprecated "GIL Refs" API.
@@ -311,12 +312,6 @@ impl<'py, T> Borrowed<'py, 'py, T>
 where
     T: HasPyGilRef,
 {
-    pub(crate) fn from_gil_ref(gil_ref: &'py T::AsRefTarget) -> Self {
-        // Safety: &'py T::AsRefTarget is expected to be a Python pointer,
-        // so &'py T::AsRefTarget has the same layout as Self.
-        unsafe { std::mem::transmute(gil_ref) }
-    }
-
     // pub(crate) fn into_gil_ref(self) -> &'py T::AsRefTarget {
     //     // Safety: self is a borrow over `'py`.
     //     unsafe { self.py().from_borrowed_ptr(self.0.as_ptr()) }
@@ -1366,7 +1361,7 @@ where
 {
     /// Extracts `Self` from the source `PyObject`.
     fn extract(ob: &'a PyAny) -> PyResult<Self> {
-        Bound::borrowed_from_gil_ref(&ob)
+        ob.as_borrowed()
             .downcast()
             .map(Clone::clone)
             .map_err(Into::into)
@@ -1485,7 +1480,7 @@ impl PyObject {
 mod tests {
     use super::{Bound, Py, PyObject};
     use crate::types::{PyDict, PyString};
-    use crate::{PyAny, PyResult, Python, ToPyObject};
+    use crate::{PyAny, PyNativeType, PyResult, Python, ToPyObject};
 
     #[test]
     fn test_call0() {
@@ -1612,8 +1607,11 @@ a = A()
     #[test]
     fn test_py2_into_py_object() {
         Python::with_gil(|py| {
-            let instance: Bound<'_, PyAny> =
-                Bound::borrowed_from_gil_ref(&py.eval("object()", None, None).unwrap()).clone();
+            let instance = py
+                .eval("object()", None, None)
+                .unwrap()
+                .as_borrowed()
+                .to_owned();
             let ptr = instance.as_ptr();
             let instance: PyObject = instance.clone().into();
             assert_eq!(instance.as_ptr(), ptr);
diff --git a/src/prelude.rs b/src/prelude.rs
index 866b2226765..b06625dc36a 100644
--- a/src/prelude.rs
+++ b/src/prelude.rs
@@ -17,6 +17,7 @@ pub use crate::marker::Python;
 pub use crate::pycell::{PyCell, PyRef, PyRefMut};
 pub use crate::pyclass_init::PyClassInitializer;
 pub use crate::types::{PyAny, PyModule};
+pub use crate::PyNativeType;
 
 #[cfg(feature = "macros")]
 pub use pyo3_macros::{pyclass, pyfunction, pymethods, pymodule, FromPyObject};
diff --git a/src/types/any.rs b/src/types/any.rs
index b8e8c03ad06..edc74879cb6 100644
--- a/src/types/any.rs
+++ b/src/types/any.rs
@@ -73,7 +73,7 @@ impl PyAny {
     /// This is equivalent to the Python expression `self is other`.
     #[inline]
     pub fn is<T: AsPyPointer>(&self, other: &T) -> bool {
-        Bound::borrowed_from_gil_ref(&self).is(other)
+        self.as_borrowed().is(other)
     }
 
     /// Determines whether this object has the given attribute.
@@ -102,7 +102,7 @@ impl PyAny {
     where
         N: IntoPy<Py<PyString>>,
     {
-        Bound::borrowed_from_gil_ref(&self).hasattr(attr_name)
+        self.as_borrowed().hasattr(attr_name)
     }
 
     /// Retrieves an attribute value.
@@ -131,7 +131,7 @@ impl PyAny {
     where
         N: IntoPy<Py<PyString>>,
     {
-        Bound::borrowed_from_gil_ref(&self)
+        self.as_borrowed()
             .getattr(attr_name)
             .map(Bound::into_gil_ref)
     }
@@ -208,7 +208,7 @@ impl PyAny {
         N: IntoPy<Py<PyString>>,
         V: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).setattr(attr_name, value)
+        self.as_borrowed().setattr(attr_name, value)
     }
 
     /// Deletes an attribute.
@@ -221,7 +221,7 @@ impl PyAny {
     where
         N: IntoPy<Py<PyString>>,
     {
-        Bound::borrowed_from_gil_ref(&self).delattr(attr_name)
+        self.as_borrowed().delattr(attr_name)
     }
 
     /// Returns an [`Ordering`] between `self` and `other`.
@@ -274,7 +274,7 @@ impl PyAny {
     where
         O: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).compare(other)
+        self.as_borrowed().compare(other)
     }
 
     /// Tests whether two Python objects obey a given [`CompareOp`].
@@ -315,7 +315,7 @@ impl PyAny {
     where
         O: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self)
+        self.as_borrowed()
             .rich_compare(other, compare_op)
             .map(Bound::into_gil_ref)
     }
@@ -327,7 +327,7 @@ impl PyAny {
     where
         O: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).lt(other)
+        self.as_borrowed().lt(other)
     }
 
     /// Tests whether this object is less than or equal to another.
@@ -337,7 +337,7 @@ impl PyAny {
     where
         O: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).le(other)
+        self.as_borrowed().le(other)
     }
 
     /// Tests whether this object is equal to another.
@@ -347,7 +347,7 @@ impl PyAny {
     where
         O: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).eq(other)
+        self.as_borrowed().eq(other)
     }
 
     /// Tests whether this object is not equal to another.
@@ -357,7 +357,7 @@ impl PyAny {
     where
         O: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).ne(other)
+        self.as_borrowed().ne(other)
     }
 
     /// Tests whether this object is greater than another.
@@ -367,7 +367,7 @@ impl PyAny {
     where
         O: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).gt(other)
+        self.as_borrowed().gt(other)
     }
 
     /// Tests whether this object is greater than or equal to another.
@@ -377,7 +377,7 @@ impl PyAny {
     where
         O: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).ge(other)
+        self.as_borrowed().ge(other)
     }
 
     /// Determines whether this object appears callable.
@@ -408,7 +408,7 @@ impl PyAny {
     ///
     /// [1]: https://docs.python.org/3/library/functions.html#callable
     pub fn is_callable(&self) -> bool {
-        Bound::borrowed_from_gil_ref(&self).is_callable()
+        self.as_borrowed().is_callable()
     }
 
     /// Calls the object.
@@ -446,7 +446,7 @@ impl PyAny {
         args: impl IntoPy<Py<PyTuple>>,
         kwargs: Option<&PyDict>,
     ) -> PyResult<&PyAny> {
-        Bound::borrowed_from_gil_ref(&self)
+        self.as_borrowed()
             .call(args, kwargs)
             .map(Bound::into_gil_ref)
     }
@@ -472,9 +472,7 @@ impl PyAny {
     ///
     /// This is equivalent to the Python expression `help()`.
     pub fn call0(&self) -> PyResult<&PyAny> {
-        Bound::borrowed_from_gil_ref(&self)
-            .call0()
-            .map(Bound::into_gil_ref)
+        self.as_borrowed().call0().map(Bound::into_gil_ref)
     }
 
     /// Calls the object with only positional arguments.
@@ -505,9 +503,7 @@ impl PyAny {
     /// # }
     /// ```
     pub fn call1(&self, args: impl IntoPy<Py<PyTuple>>) -> PyResult<&PyAny> {
-        Bound::borrowed_from_gil_ref(&self)
-            .call1(args)
-            .map(Bound::into_gil_ref)
+        self.as_borrowed().call1(args).map(Bound::into_gil_ref)
     }
 
     /// Calls a method on the object.
@@ -550,7 +546,7 @@ impl PyAny {
         N: IntoPy<Py<PyString>>,
         A: IntoPy<Py<PyTuple>>,
     {
-        Bound::borrowed_from_gil_ref(&self)
+        self.as_borrowed()
             .call_method(name, args, kwargs)
             .map(Bound::into_gil_ref)
     }
@@ -590,7 +586,7 @@ impl PyAny {
     where
         N: IntoPy<Py<PyString>>,
     {
-        Bound::borrowed_from_gil_ref(&self)
+        self.as_borrowed()
             .call_method0(name)
             .map(Bound::into_gil_ref)
     }
@@ -632,7 +628,7 @@ impl PyAny {
         N: IntoPy<Py<PyString>>,
         A: IntoPy<Py<PyTuple>>,
     {
-        Bound::borrowed_from_gil_ref(&self)
+        self.as_borrowed()
             .call_method1(name, args)
             .map(Bound::into_gil_ref)
     }
@@ -649,7 +645,7 @@ impl PyAny {
     ///
     /// This applies truth value testing equivalent to the Python expression `bool(self)`.
     pub fn is_truthy(&self) -> PyResult<bool> {
-        Bound::borrowed_from_gil_ref(&self).is_truthy()
+        self.as_borrowed().is_truthy()
     }
 
     /// Returns whether the object is considered to be None.
@@ -657,7 +653,7 @@ impl PyAny {
     /// This is equivalent to the Python expression `self is None`.
     #[inline]
     pub fn is_none(&self) -> bool {
-        Bound::borrowed_from_gil_ref(&self).is_none()
+        self.as_borrowed().is_none()
     }
 
     /// Returns whether the object is Ellipsis, e.g. `...`.
@@ -665,14 +661,14 @@ impl PyAny {
     /// 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 {
-        Bound::borrowed_from_gil_ref(&self).is_ellipsis()
+        self.as_borrowed().is_ellipsis()
     }
 
     /// Returns true if the sequence or mapping has a length of 0.
     ///
     /// This is equivalent to the Python expression `len(self) == 0`.
     pub fn is_empty(&self) -> PyResult<bool> {
-        Bound::borrowed_from_gil_ref(&self).is_empty()
+        self.as_borrowed().is_empty()
     }
 
     /// Gets an item from the collection.
@@ -682,9 +678,7 @@ impl PyAny {
     where
         K: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self)
-            .get_item(key)
-            .map(Bound::into_gil_ref)
+        self.as_borrowed().get_item(key).map(Bound::into_gil_ref)
     }
 
     /// Sets a collection item value.
@@ -695,7 +689,7 @@ impl PyAny {
         K: ToPyObject,
         V: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).set_item(key, value)
+        self.as_borrowed().set_item(key, value)
     }
 
     /// Deletes an item from the collection.
@@ -705,7 +699,7 @@ impl PyAny {
     where
         K: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).del_item(key)
+        self.as_borrowed().del_item(key)
     }
 
     /// Takes an object and returns an iterator for it.
@@ -713,20 +707,18 @@ impl PyAny {
     /// This is typically a new iterator but if the argument is an iterator,
     /// this returns itself.
     pub fn iter(&self) -> PyResult<&PyIterator> {
-        Bound::borrowed_from_gil_ref(&self)
-            .iter()
-            .map(Bound::into_gil_ref)
+        self.as_borrowed().iter().map(Bound::into_gil_ref)
     }
 
     /// Returns the Python type object for this object's type.
     pub fn get_type(&self) -> &PyType {
-        Bound::borrowed_from_gil_ref(&self).get_type()
+        self.as_borrowed().get_type()
     }
 
     /// Returns the Python type pointer for this object.
     #[inline]
     pub fn get_type_ptr(&self) -> *mut ffi::PyTypeObject {
-        Bound::borrowed_from_gil_ref(&self).get_type_ptr()
+        self.as_borrowed().get_type_ptr()
     }
 
     /// Downcast this `PyAny` to a concrete Python type or pyclass.
@@ -863,46 +855,42 @@ impl PyAny {
 
     /// Returns the reference count for the Python object.
     pub fn get_refcnt(&self) -> isize {
-        Bound::borrowed_from_gil_ref(&self).get_refcnt()
+        self.as_borrowed().get_refcnt()
     }
 
     /// Computes the "repr" representation of self.
     ///
     /// This is equivalent to the Python expression `repr(self)`.
     pub fn repr(&self) -> PyResult<&PyString> {
-        Bound::borrowed_from_gil_ref(&self)
-            .repr()
-            .map(Bound::into_gil_ref)
+        self.as_borrowed().repr().map(Bound::into_gil_ref)
     }
 
     /// Computes the "str" representation of self.
     ///
     /// This is equivalent to the Python expression `str(self)`.
     pub fn str(&self) -> PyResult<&PyString> {
-        Bound::borrowed_from_gil_ref(&self)
-            .str()
-            .map(Bound::into_gil_ref)
+        self.as_borrowed().str().map(Bound::into_gil_ref)
     }
 
     /// Retrieves the hash code of self.
     ///
     /// This is equivalent to the Python expression `hash(self)`.
     pub fn hash(&self) -> PyResult<isize> {
-        Bound::borrowed_from_gil_ref(&self).hash()
+        self.as_borrowed().hash()
     }
 
     /// Returns the length of the sequence or mapping.
     ///
     /// This is equivalent to the Python expression `len(self)`.
     pub fn len(&self) -> PyResult<usize> {
-        Bound::borrowed_from_gil_ref(&self).len()
+        self.as_borrowed().len()
     }
 
     /// Returns the list of attributes of this object.
     ///
     /// This is equivalent to the Python expression `dir(self)`.
     pub fn dir(&self) -> &PyList {
-        Bound::borrowed_from_gil_ref(&self).dir().into_gil_ref()
+        self.as_borrowed().dir().into_gil_ref()
     }
 
     /// Checks whether this object is an instance of type `ty`.
@@ -910,7 +898,7 @@ impl PyAny {
     /// This is equivalent to the Python expression `isinstance(self, ty)`.
     #[inline]
     pub fn is_instance(&self, ty: &PyAny) -> PyResult<bool> {
-        Bound::borrowed_from_gil_ref(&self).is_instance(Bound::borrowed_from_gil_ref(&ty))
+        self.as_borrowed().is_instance(&ty.as_borrowed())
     }
 
     /// Checks whether this object is an instance of exactly type `ty` (not a subclass).
@@ -918,7 +906,7 @@ impl PyAny {
     /// This is equivalent to the Python expression `type(self) is ty`.
     #[inline]
     pub fn is_exact_instance(&self, ty: &PyAny) -> bool {
-        Bound::borrowed_from_gil_ref(&self).is_exact_instance(Bound::borrowed_from_gil_ref(&ty))
+        self.as_borrowed().is_exact_instance(&ty.as_borrowed())
     }
 
     /// Checks whether this object is an instance of type `T`.
@@ -927,7 +915,7 @@ impl PyAny {
     /// if the type `T` is known at compile time.
     #[inline]
     pub fn is_instance_of<T: PyTypeInfo>(&self) -> bool {
-        Bound::borrowed_from_gil_ref(&self).is_instance_of::<T>()
+        self.as_borrowed().is_instance_of::<T>()
     }
 
     /// Checks whether this object is an instance of exactly type `T`.
@@ -936,7 +924,7 @@ impl PyAny {
     /// if the type `T` is known at compile time.
     #[inline]
     pub fn is_exact_instance_of<T: PyTypeInfo>(&self) -> bool {
-        Bound::borrowed_from_gil_ref(&self).is_exact_instance_of::<T>()
+        self.as_borrowed().is_exact_instance_of::<T>()
     }
 
     /// Determines if self contains `value`.
@@ -946,7 +934,7 @@ impl PyAny {
     where
         V: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).contains(value)
+        self.as_borrowed().contains(value)
     }
 
     /// Returns a GIL marker constrained to the lifetime of this type.
@@ -985,9 +973,7 @@ impl PyAny {
     /// This is equivalent to the Python expression `super()`
     #[cfg(not(PyPy))]
     pub fn py_super(&self) -> PyResult<&PySuper> {
-        Bound::borrowed_from_gil_ref(&self)
-            .py_super()
-            .map(Bound::into_gil_ref)
+        self.as_borrowed().py_super().map(Bound::into_gil_ref)
     }
 }
 
@@ -2193,7 +2179,7 @@ impl<'py> PyAnyMethods<'py> for Bound<'py, PyAny> {
 
     #[cfg(not(PyPy))]
     fn py_super(&self) -> PyResult<Bound<'py, PySuper>> {
-        PySuper::new_bound(Bound::borrowed_from_gil_ref(&self.get_type()), self)
+        PySuper::new_bound(&self.get_type().as_borrowed(), self)
     }
 }
 
diff --git a/src/types/boolobject.rs b/src/types/boolobject.rs
index 55896f877c5..5c246de380d 100644
--- a/src/types/boolobject.rs
+++ b/src/types/boolobject.rs
@@ -1,8 +1,8 @@
 #[cfg(feature = "experimental-inspect")]
 use crate::inspect::types::TypeInfo;
 use crate::{
-    exceptions::PyTypeError, ffi, instance::Bound, FromPyObject, IntoPy, PyAny, PyObject, PyResult,
-    Python, ToPyObject,
+    exceptions::PyTypeError, ffi, instance::Bound, FromPyObject, IntoPy, PyAny, PyNativeType,
+    PyObject, PyResult, Python, ToPyObject,
 };
 
 /// Represents a Python `bool`.
@@ -21,7 +21,7 @@ impl PyBool {
     /// Gets whether this boolean is `true`.
     #[inline]
     pub fn is_true(&self) -> bool {
-        Bound::borrowed_from_gil_ref(&self).is_true()
+        self.as_borrowed().is_true()
     }
 }
 
diff --git a/src/types/bytearray.rs b/src/types/bytearray.rs
index a90fec82273..f1b8050c066 100644
--- a/src/types/bytearray.rs
+++ b/src/types/bytearray.rs
@@ -1,6 +1,6 @@
 use crate::err::{PyErr, PyResult};
 use crate::instance::{Borrowed, Bound};
-use crate::{ffi, AsPyPointer, Py, PyAny, Python};
+use crate::{ffi, AsPyPointer, Py, PyAny, PyNativeType, Python};
 use std::os::raw::c_char;
 use std::slice;
 
@@ -75,12 +75,12 @@ impl PyByteArray {
     /// Gets the length of the bytearray.
     #[inline]
     pub fn len(&self) -> usize {
-        Bound::borrowed_from_gil_ref(&self).len()
+        self.as_borrowed().len()
     }
 
     /// Checks if the bytearray is empty.
     pub fn is_empty(&self) -> bool {
-        Bound::borrowed_from_gil_ref(&self).is_empty()
+        self.as_borrowed().is_empty()
     }
 
     /// Gets the start of the buffer containing the contents of the bytearray.
@@ -89,7 +89,7 @@ impl PyByteArray {
     ///
     /// See the safety requirements of [`PyByteArray::as_bytes`] and [`PyByteArray::as_bytes_mut`].
     pub fn data(&self) -> *mut u8 {
-        Bound::borrowed_from_gil_ref(&self).data()
+        self.as_borrowed().data()
     }
 
     /// Extracts a slice of the `ByteArray`'s entire buffer.
@@ -188,7 +188,7 @@ impl PyByteArray {
     /// }
     /// ```
     pub unsafe fn as_bytes(&self) -> &[u8] {
-        Borrowed::from_gil_ref(self).as_bytes()
+        self.as_borrowed().as_bytes()
     }
 
     /// Extracts a mutable slice of the `ByteArray`'s entire buffer.
@@ -200,7 +200,7 @@ impl PyByteArray {
     /// apply to this function as well.
     #[allow(clippy::mut_from_ref)]
     pub unsafe fn as_bytes_mut(&self) -> &mut [u8] {
-        Borrowed::from_gil_ref(self).as_bytes_mut()
+        self.as_borrowed().as_bytes_mut()
     }
 
     /// Copies the contents of the bytearray to a Rust vector.
@@ -222,7 +222,7 @@ impl PyByteArray {
     /// # });
     /// ```
     pub fn to_vec(&self) -> Vec<u8> {
-        Bound::borrowed_from_gil_ref(&self).to_vec()
+        self.as_borrowed().to_vec()
     }
 
     /// Resizes the bytearray object to the new length `len`.
@@ -230,7 +230,7 @@ impl PyByteArray {
     /// Note that this will invalidate any pointers obtained by [PyByteArray::data], as well as
     /// any (unsafe) slices obtained from [PyByteArray::as_bytes] and [PyByteArray::as_bytes_mut].
     pub fn resize(&self, len: usize) -> PyResult<()> {
-        Bound::borrowed_from_gil_ref(&self).resize(len)
+        self.as_borrowed().resize(len)
     }
 }
 
diff --git a/src/types/bytes.rs b/src/types/bytes.rs
index 4db098c6bb6..5a7b174ea0c 100644
--- a/src/types/bytes.rs
+++ b/src/types/bytes.rs
@@ -1,5 +1,5 @@
 use crate::instance::{Borrowed, Bound};
-use crate::{ffi, FromPyObject, IntoPy, Py, PyAny, PyResult, Python, ToPyObject};
+use crate::{ffi, FromPyObject, IntoPy, Py, PyAny, PyNativeType, PyResult, Python, ToPyObject};
 use std::borrow::Cow;
 use std::ops::Index;
 use std::os::raw::c_char;
@@ -89,7 +89,7 @@ impl PyBytes {
     /// Gets the Python string as a byte slice.
     #[inline]
     pub fn as_bytes(&self) -> &[u8] {
-        Borrowed::from_gil_ref(self).as_bytes()
+        self.as_borrowed().as_bytes()
     }
 }
 
diff --git a/src/types/datetime.rs b/src/types/datetime.rs
index b2d0f6efa00..b671249c983 100644
--- a/src/types/datetime.rs
+++ b/src/types/datetime.rs
@@ -223,15 +223,15 @@ impl PyDate {
 
 impl PyDateAccess for PyDate {
     fn get_year(&self) -> i32 {
-        Bound::borrowed_from_gil_ref(&self).get_year()
+        self.as_borrowed().get_year()
     }
 
     fn get_month(&self) -> u8 {
-        Bound::borrowed_from_gil_ref(&self).get_month()
+        self.as_borrowed().get_month()
     }
 
     fn get_day(&self) -> u8 {
-        Bound::borrowed_from_gil_ref(&self).get_day()
+        self.as_borrowed().get_day()
     }
 }
 
@@ -351,15 +351,15 @@ impl PyDateTime {
 
 impl PyDateAccess for PyDateTime {
     fn get_year(&self) -> i32 {
-        Bound::borrowed_from_gil_ref(&self).get_year()
+        self.as_borrowed().get_year()
     }
 
     fn get_month(&self) -> u8 {
-        Bound::borrowed_from_gil_ref(&self).get_month()
+        self.as_borrowed().get_month()
     }
 
     fn get_day(&self) -> u8 {
-        Bound::borrowed_from_gil_ref(&self).get_day()
+        self.as_borrowed().get_day()
     }
 }
 
@@ -379,23 +379,23 @@ impl PyDateAccess for Bound<'_, PyDateTime> {
 
 impl PyTimeAccess for PyDateTime {
     fn get_hour(&self) -> u8 {
-        Bound::borrowed_from_gil_ref(&self).get_hour()
+        self.as_borrowed().get_hour()
     }
 
     fn get_minute(&self) -> u8 {
-        Bound::borrowed_from_gil_ref(&self).get_minute()
+        self.as_borrowed().get_minute()
     }
 
     fn get_second(&self) -> u8 {
-        Bound::borrowed_from_gil_ref(&self).get_second()
+        self.as_borrowed().get_second()
     }
 
     fn get_microsecond(&self) -> u32 {
-        Bound::borrowed_from_gil_ref(&self).get_microsecond()
+        self.as_borrowed().get_microsecond()
     }
 
     fn get_fold(&self) -> bool {
-        Bound::borrowed_from_gil_ref(&self).get_fold()
+        self.as_borrowed().get_fold()
     }
 }
 
@@ -423,7 +423,7 @@ impl PyTimeAccess for Bound<'_, PyDateTime> {
 
 impl<'py> PyTzInfoAccess<'py> for &'py PyDateTime {
     fn get_tzinfo_bound(&self) -> Option<Bound<'py, PyTzInfo>> {
-        Bound::borrowed_from_gil_ref(self).get_tzinfo_bound()
+        self.as_borrowed().get_tzinfo_bound()
     }
 }
 
@@ -509,23 +509,23 @@ impl PyTime {
 
 impl PyTimeAccess for PyTime {
     fn get_hour(&self) -> u8 {
-        Bound::borrowed_from_gil_ref(&self).get_hour()
+        self.as_borrowed().get_hour()
     }
 
     fn get_minute(&self) -> u8 {
-        Bound::borrowed_from_gil_ref(&self).get_minute()
+        self.as_borrowed().get_minute()
     }
 
     fn get_second(&self) -> u8 {
-        Bound::borrowed_from_gil_ref(&self).get_second()
+        self.as_borrowed().get_second()
     }
 
     fn get_microsecond(&self) -> u32 {
-        Bound::borrowed_from_gil_ref(&self).get_microsecond()
+        self.as_borrowed().get_microsecond()
     }
 
     fn get_fold(&self) -> bool {
-        Bound::borrowed_from_gil_ref(&self).get_fold()
+        self.as_borrowed().get_fold()
     }
 }
 
@@ -553,7 +553,7 @@ impl PyTimeAccess for Bound<'_, PyTime> {
 
 impl<'py> PyTzInfoAccess<'py> for &'py PyTime {
     fn get_tzinfo_bound(&self) -> Option<Bound<'py, PyTzInfo>> {
-        Bound::borrowed_from_gil_ref(self).get_tzinfo_bound()
+        self.as_borrowed().get_tzinfo_bound()
     }
 }
 
@@ -644,15 +644,15 @@ impl PyDelta {
 
 impl PyDeltaAccess for PyDelta {
     fn get_days(&self) -> i32 {
-        Bound::borrowed_from_gil_ref(&self).get_days()
+        self.as_borrowed().get_days()
     }
 
     fn get_seconds(&self) -> i32 {
-        Bound::borrowed_from_gil_ref(&self).get_seconds()
+        self.as_borrowed().get_seconds()
     }
 
     fn get_microseconds(&self) -> i32 {
-        Bound::borrowed_from_gil_ref(&self).get_microseconds()
+        self.as_borrowed().get_microseconds()
     }
 }
 
diff --git a/src/types/dict.rs b/src/types/dict.rs
index 89e0df96e63..80d2798a863 100644
--- a/src/types/dict.rs
+++ b/src/types/dict.rs
@@ -6,7 +6,7 @@ use crate::instance::{Borrowed, Bound};
 use crate::py_result_ext::PyResultExt;
 use crate::types::any::PyAnyMethods;
 use crate::types::{PyAny, PyList};
-use crate::{ffi, Python, ToPyObject};
+use crate::{ffi, PyNativeType, Python, ToPyObject};
 
 /// Represents a Python `dict`.
 #[repr(transparent)]
@@ -82,26 +82,24 @@ impl PyDict {
     ///
     /// This is equivalent to the Python expression `self.copy()`.
     pub fn copy(&self) -> PyResult<&PyDict> {
-        Bound::borrowed_from_gil_ref(&self)
-            .copy()
-            .map(Bound::into_gil_ref)
+        self.as_borrowed().copy().map(Bound::into_gil_ref)
     }
 
     /// Empties an existing dictionary of all key-value pairs.
     pub fn clear(&self) {
-        Bound::borrowed_from_gil_ref(&self).clear()
+        self.as_borrowed().clear()
     }
 
     /// Return the number of items in the dictionary.
     ///
     /// This is equivalent to the Python expression `len(self)`.
     pub fn len(&self) -> usize {
-        Bound::borrowed_from_gil_ref(&self).len()
+        self.as_borrowed().len()
     }
 
     /// Checks if the dict is empty, i.e. `len(self) == 0`.
     pub fn is_empty(&self) -> bool {
-        Bound::borrowed_from_gil_ref(&self).is_empty()
+        self.as_borrowed().is_empty()
     }
 
     /// Determines if the dictionary contains the specified key.
@@ -111,7 +109,7 @@ impl PyDict {
     where
         K: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).contains(key)
+        self.as_borrowed().contains(key)
     }
 
     /// Gets an item from the dictionary.
@@ -160,7 +158,7 @@ impl PyDict {
     where
         K: ToPyObject,
     {
-        match Bound::borrowed_from_gil_ref(&self).get_item(key) {
+        match self.as_borrowed().get_item(key) {
             Ok(Some(item)) => Ok(Some(item.into_gil_ref())),
             Ok(None) => Ok(None),
             Err(e) => Err(e),
@@ -188,7 +186,7 @@ impl PyDict {
         K: ToPyObject,
         V: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).set_item(key, value)
+        self.as_borrowed().set_item(key, value)
     }
 
     /// Deletes an item.
@@ -198,28 +196,28 @@ impl PyDict {
     where
         K: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).del_item(key)
+        self.as_borrowed().del_item(key)
     }
 
     /// Returns a list of dict keys.
     ///
     /// This is equivalent to the Python expression `list(dict.keys())`.
     pub fn keys(&self) -> &PyList {
-        Bound::borrowed_from_gil_ref(&self).keys().into_gil_ref()
+        self.as_borrowed().keys().into_gil_ref()
     }
 
     /// Returns a list of dict values.
     ///
     /// This is equivalent to the Python expression `list(dict.values())`.
     pub fn values(&self) -> &PyList {
-        Bound::borrowed_from_gil_ref(&self).values().into_gil_ref()
+        self.as_borrowed().values().into_gil_ref()
     }
 
     /// Returns a list of dict items.
     ///
     /// This is equivalent to the Python expression `list(dict.items())`.
     pub fn items(&self) -> &PyList {
-        Bound::borrowed_from_gil_ref(&self).items().into_gil_ref()
+        self.as_borrowed().items().into_gil_ref()
     }
 
     /// Returns an iterator of `(key, value)` pairs in this dictionary.
@@ -230,7 +228,7 @@ impl PyDict {
     /// It is allowed to modify values as you iterate over the dictionary, but only
     /// so long as the set of keys does not change.
     pub fn iter(&self) -> PyDictIterator<'_> {
-        PyDictIterator(Bound::borrowed_from_gil_ref(&self).iter())
+        PyDictIterator(self.as_borrowed().iter())
     }
 
     /// Returns `self` cast as a `PyMapping`.
@@ -243,7 +241,7 @@ impl PyDict {
     /// This is equivalent to the Python expression `self.update(other)`. If `other` is a `PyDict`, you may want
     /// to use `self.update(other.as_mapping())`, note: `PyDict::as_mapping` is a zero-cost conversion.
     pub fn update(&self, other: &PyMapping) -> PyResult<()> {
-        Bound::borrowed_from_gil_ref(&self).update(Bound::borrowed_from_gil_ref(&other))
+        self.as_borrowed().update(&other.as_borrowed())
     }
 
     /// Add key/value pairs from another dictionary to this one only when they do not exist in this.
@@ -255,7 +253,7 @@ impl PyDict {
     /// This method uses [`PyDict_Merge`](https://docs.python.org/3/c-api/dict.html#c.PyDict_Merge) internally,
     /// so should have the same performance as `update`.
     pub fn update_if_missing(&self, other: &PyMapping) -> PyResult<()> {
-        Bound::borrowed_from_gil_ref(&self).update_if_missing(Bound::borrowed_from_gil_ref(&other))
+        self.as_borrowed().update_if_missing(&other.as_borrowed())
     }
 }
 
diff --git a/src/types/float.rs b/src/types/float.rs
index bb55d7ed5f5..b6dabdc48e8 100644
--- a/src/types/float.rs
+++ b/src/types/float.rs
@@ -29,7 +29,7 @@ impl PyFloat {
 
     /// Gets the value of this float.
     pub fn value(&self) -> c_double {
-        Bound::borrowed_from_gil_ref(&self).value()
+        self.as_borrowed().value()
     }
 }
 
diff --git a/src/types/iterator.rs b/src/types/iterator.rs
index 0e033232964..67866348f8c 100644
--- a/src/types/iterator.rs
+++ b/src/types/iterator.rs
@@ -35,7 +35,7 @@ impl PyIterator {
     ///
     /// Equivalent to Python's built-in `iter` function.
     pub fn from_object(obj: &PyAny) -> PyResult<&PyIterator> {
-        Self::from_object2(Bound::borrowed_from_gil_ref(&obj)).map(Bound::into_gil_ref)
+        Self::from_object2(&obj.as_borrowed()).map(Bound::into_gil_ref)
     }
 
     pub(crate) fn from_object2<'py>(obj: &Bound<'py, PyAny>) -> PyResult<Bound<'py, PyIterator>> {
@@ -57,14 +57,14 @@ impl<'p> Iterator for &'p PyIterator {
     /// Further `next()` calls after an exception occurs are likely
     /// to repeatedly result in the same exception.
     fn next(&mut self) -> Option<Self::Item> {
-        Borrowed::<PyIterator>::from_gil_ref(self)
+        self.as_borrowed()
             .next()
             .map(|result| result.map(Bound::into_gil_ref))
     }
 
     #[cfg(not(Py_LIMITED_API))]
     fn size_hint(&self) -> (usize, Option<usize>) {
-        Bound::borrowed_from_gil_ref(self).size_hint()
+        self.as_borrowed().size_hint()
     }
 }
 
diff --git a/src/types/list.rs b/src/types/list.rs
index 0e7fc952b00..cdc39349bfd 100644
--- a/src/types/list.rs
+++ b/src/types/list.rs
@@ -7,7 +7,7 @@ use crate::ffi_ptr_ext::FfiPtrExt;
 use crate::instance::Borrowed;
 use crate::internal_tricks::get_ssize_index;
 use crate::types::{PySequence, PyTuple};
-use crate::{Bound, PyAny, PyObject, Python, ToPyObject};
+use crate::{Bound, PyAny, PyNativeType, PyObject, Python, ToPyObject};
 
 use crate::types::any::PyAnyMethods;
 use crate::types::sequence::PySequenceMethods;
@@ -98,12 +98,12 @@ impl PyList {
 
     /// Returns the length of the list.
     pub fn len(&self) -> usize {
-        Bound::borrowed_from_gil_ref(&self).len()
+        self.as_borrowed().len()
     }
 
     /// Checks if the list is empty.
     pub fn is_empty(&self) -> bool {
-        Bound::borrowed_from_gil_ref(&self).is_empty()
+        self.as_borrowed().is_empty()
     }
 
     /// Returns `self` cast as a `PySequence`.
@@ -122,9 +122,7 @@ impl PyList {
     /// });
     /// ```
     pub fn get_item(&self, index: usize) -> PyResult<&PyAny> {
-        Bound::borrowed_from_gil_ref(&self)
-            .get_item(index)
-            .map(Bound::into_gil_ref)
+        self.as_borrowed().get_item(index).map(Bound::into_gil_ref)
     }
 
     /// Gets the list item at the specified index. Undefined behavior on bad index. Use with caution.
@@ -134,9 +132,7 @@ impl PyList {
     /// Caller must verify that the index is within the bounds of the list.
     #[cfg(not(Py_LIMITED_API))]
     pub unsafe fn get_item_unchecked(&self, index: usize) -> &PyAny {
-        Bound::borrowed_from_gil_ref(&self)
-            .get_item_unchecked(index)
-            .into_gil_ref()
+        self.as_borrowed().get_item_unchecked(index).into_gil_ref()
     }
 
     /// Takes the slice `self[low:high]` and returns it as a new list.
@@ -144,9 +140,7 @@ impl PyList {
     /// Indices must be nonnegative, and out-of-range indices are clipped to
     /// `self.len()`.
     pub fn get_slice(&self, low: usize, high: usize) -> &PyList {
-        Bound::borrowed_from_gil_ref(&self)
-            .get_slice(low, high)
-            .into_gil_ref()
+        self.as_borrowed().get_slice(low, high).into_gil_ref()
     }
 
     /// Sets the item at the specified index.
@@ -156,7 +150,7 @@ impl PyList {
     where
         I: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).set_item(index, item)
+        self.as_borrowed().set_item(index, item)
     }
 
     /// Deletes the `index`th element of self.
@@ -164,7 +158,7 @@ impl PyList {
     /// This is equivalent to the Python statement `del self[i]`.
     #[inline]
     pub fn del_item(&self, index: usize) -> PyResult<()> {
-        Bound::borrowed_from_gil_ref(&self).del_item(index)
+        self.as_borrowed().del_item(index)
     }
 
     /// Assigns the sequence `seq` to the slice of `self` from `low` to `high`.
@@ -172,7 +166,7 @@ impl PyList {
     /// This is equivalent to the Python statement `self[low:high] = v`.
     #[inline]
     pub fn set_slice(&self, low: usize, high: usize, seq: &PyAny) -> PyResult<()> {
-        Bound::borrowed_from_gil_ref(&self).set_slice(low, high, Bound::borrowed_from_gil_ref(&seq))
+        self.as_borrowed().set_slice(low, high, &seq.as_borrowed())
     }
 
     /// Deletes the slice from `low` to `high` from `self`.
@@ -180,7 +174,7 @@ impl PyList {
     /// This is equivalent to the Python statement `del self[low:high]`.
     #[inline]
     pub fn del_slice(&self, low: usize, high: usize) -> PyResult<()> {
-        Bound::borrowed_from_gil_ref(&self).del_slice(low, high)
+        self.as_borrowed().del_slice(low, high)
     }
 
     /// Appends an item to the list.
@@ -188,7 +182,7 @@ impl PyList {
     where
         I: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).append(item)
+        self.as_borrowed().append(item)
     }
 
     /// Inserts an item at the specified index.
@@ -198,7 +192,7 @@ impl PyList {
     where
         I: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).insert(index, item)
+        self.as_borrowed().insert(index, item)
     }
 
     /// Determines if self contains `value`.
@@ -209,7 +203,7 @@ impl PyList {
     where
         V: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).contains(value)
+        self.as_borrowed().contains(value)
     }
 
     /// Returns the first index `i` for which `self[i] == value`.
@@ -220,31 +214,29 @@ impl PyList {
     where
         V: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).index(value)
+        self.as_borrowed().index(value)
     }
 
     /// Returns an iterator over this list's items.
     pub fn iter(&self) -> PyListIterator<'_> {
-        PyListIterator(Bound::borrowed_from_gil_ref(&self).iter())
+        PyListIterator(self.as_borrowed().iter())
     }
 
     /// Sorts the list in-place. Equivalent to the Python expression `l.sort()`.
     pub fn sort(&self) -> PyResult<()> {
-        Bound::borrowed_from_gil_ref(&self).sort()
+        self.as_borrowed().sort()
     }
 
     /// Reverses the list in-place. Equivalent to the Python expression `l.reverse()`.
     pub fn reverse(&self) -> PyResult<()> {
-        Bound::borrowed_from_gil_ref(&self).reverse()
+        self.as_borrowed().reverse()
     }
 
     /// Return a new tuple containing the contents of the list; equivalent to the Python expression `tuple(list)`.
     ///
     /// This method is equivalent to `self.as_sequence().to_tuple()` and faster than `PyTuple::new(py, this_list)`.
     pub fn to_tuple(&self) -> &PyTuple {
-        Bound::borrowed_from_gil_ref(&self)
-            .to_tuple()
-            .into_gil_ref()
+        self.as_borrowed().to_tuple().into_gil_ref()
     }
 }
 
diff --git a/src/types/mapping.rs b/src/types/mapping.rs
index 239ade9b20c..4c9677cea8b 100644
--- a/src/types/mapping.rs
+++ b/src/types/mapping.rs
@@ -20,13 +20,13 @@ impl PyMapping {
     /// This is equivalent to the Python expression `len(self)`.
     #[inline]
     pub fn len(&self) -> PyResult<usize> {
-        Bound::borrowed_from_gil_ref(&self).len()
+        self.as_borrowed().len()
     }
 
     /// Returns whether the mapping is empty.
     #[inline]
     pub fn is_empty(&self) -> PyResult<bool> {
-        Bound::borrowed_from_gil_ref(&self).is_empty()
+        self.as_borrowed().is_empty()
     }
 
     /// Determines if the mapping contains the specified key.
@@ -36,7 +36,7 @@ impl PyMapping {
     where
         K: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).contains(key)
+        self.as_borrowed().contains(key)
     }
 
     /// Gets the item in self with key `key`.
@@ -49,9 +49,7 @@ impl PyMapping {
     where
         K: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self)
-            .get_item(key)
-            .map(Bound::into_gil_ref)
+        self.as_borrowed().get_item(key).map(Bound::into_gil_ref)
     }
 
     /// Sets the item in self with key `key`.
@@ -63,7 +61,7 @@ impl PyMapping {
         K: ToPyObject,
         V: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).set_item(key, value)
+        self.as_borrowed().set_item(key, value)
     }
 
     /// Deletes the item with key `key`.
@@ -74,31 +72,25 @@ impl PyMapping {
     where
         K: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).del_item(key)
+        self.as_borrowed().del_item(key)
     }
 
     /// Returns a sequence containing all keys in the mapping.
     #[inline]
     pub fn keys(&self) -> PyResult<&PySequence> {
-        Bound::borrowed_from_gil_ref(&self)
-            .keys()
-            .map(Bound::into_gil_ref)
+        self.as_borrowed().keys().map(Bound::into_gil_ref)
     }
 
     /// Returns a sequence containing all values in the mapping.
     #[inline]
     pub fn values(&self) -> PyResult<&PySequence> {
-        Bound::borrowed_from_gil_ref(&self)
-            .values()
-            .map(Bound::into_gil_ref)
+        self.as_borrowed().values().map(Bound::into_gil_ref)
     }
 
     /// Returns a sequence of tuples of all (key, value) pairs in the mapping.
     #[inline]
     pub fn items(&self) -> PyResult<&PySequence> {
-        Bound::borrowed_from_gil_ref(&self)
-            .items()
-            .map(Bound::into_gil_ref)
+        self.as_borrowed().items().map(Bound::into_gil_ref)
     }
 
     /// Register a pyclass as a subclass of `collections.abc.Mapping` (from the Python standard
@@ -257,10 +249,7 @@ impl PyTypeCheck for PyMapping {
             || get_mapping_abc(object.py())
                 .and_then(|abc| object.is_instance(abc))
                 .unwrap_or_else(|err| {
-                    err.write_unraisable_bound(
-                        object.py(),
-                        Some(Bound::borrowed_from_gil_ref(&object)),
-                    );
+                    err.write_unraisable_bound(object.py(), Some(&object.as_borrowed()));
                     false
                 })
     }
diff --git a/src/types/mod.rs b/src/types/mod.rs
index f153c4d92ec..41fb5b0adc8 100644
--- a/src/types/mod.rs
+++ b/src/types/mod.rs
@@ -105,9 +105,10 @@ macro_rules! pyobject_native_type_base(
             fn fmt(&self, f: &mut ::std::fmt::Formatter<'_>)
                    -> ::std::result::Result<(), ::std::fmt::Error>
             {
+                use $crate::PyNativeType;
                 match self.str() {
                     ::std::result::Result::Ok(s) => return f.write_str(&s.to_string_lossy()),
-                    ::std::result::Result::Err(err) => err.write_unraisable_bound(self.py(), ::std::option::Option::Some($crate::Bound::borrowed_from_gil_ref(&self))),
+                    ::std::result::Result::Err(err) => err.write_unraisable_bound(self.py(), ::std::option::Option::Some(&self.as_borrowed())),
                 }
 
                 match self.get_type().name() {
diff --git a/src/types/pysuper.rs b/src/types/pysuper.rs
index d14670987b5..23f445f76b3 100644
--- a/src/types/pysuper.rs
+++ b/src/types/pysuper.rs
@@ -1,7 +1,7 @@
 use crate::instance::Bound;
 use crate::types::any::PyAnyMethods;
 use crate::types::PyType;
-use crate::{ffi, PyTypeInfo};
+use crate::{ffi, PyNativeType, PyTypeInfo};
 use crate::{PyAny, PyResult};
 
 /// Represents a Python `super` object.
@@ -22,11 +22,7 @@ impl PySuper {
         note = "`PySuper::new` will be replaced by `PySuper::new_bound` in a future PyO3 version"
     )]
     pub fn new<'py>(ty: &'py PyType, obj: &'py PyAny) -> PyResult<&'py PySuper> {
-        Self::new_bound(
-            Bound::borrowed_from_gil_ref(&ty),
-            Bound::borrowed_from_gil_ref(&obj),
-        )
-        .map(Bound::into_gil_ref)
+        Self::new_bound(&ty.as_borrowed(), &obj.as_borrowed()).map(Bound::into_gil_ref)
     }
 
     /// Constructs a new super object. More read about super object: [docs](https://docs.python.org/3/library/functions.html#super)
@@ -73,7 +69,8 @@ impl PySuper {
         ty: &Bound<'py, PyType>,
         obj: &Bound<'py, PyAny>,
     ) -> PyResult<Bound<'py, PySuper>> {
-        Bound::borrowed_from_gil_ref(&PySuper::type_object(ty.py()))
+        PySuper::type_object(ty.py())
+            .as_borrowed()
             .call1((ty, obj))
             .map(|any| {
                 // Safety: super() always returns instance of super
diff --git a/src/types/sequence.rs b/src/types/sequence.rs
index 9b497ded4f7..f4eae4d05a9 100644
--- a/src/types/sequence.rs
+++ b/src/types/sequence.rs
@@ -23,13 +23,13 @@ impl PySequence {
     /// This is equivalent to the Python expression `len(self)`.
     #[inline]
     pub fn len(&self) -> PyResult<usize> {
-        Bound::borrowed_from_gil_ref(&self).len()
+        self.as_borrowed().len()
     }
 
     /// Returns whether the sequence is empty.
     #[inline]
     pub fn is_empty(&self) -> PyResult<bool> {
-        Bound::borrowed_from_gil_ref(&self).is_empty()
+        self.as_borrowed().is_empty()
     }
 
     /// Returns the concatenation of `self` and `other`.
@@ -37,8 +37,8 @@ impl PySequence {
     /// This is equivalent to the Python expression `self + other`.
     #[inline]
     pub fn concat(&self, other: &PySequence) -> PyResult<&PySequence> {
-        Bound::borrowed_from_gil_ref(&self)
-            .concat(Bound::borrowed_from_gil_ref(&other))
+        self.as_borrowed()
+            .concat(&other.as_borrowed())
             .map(Bound::into_gil_ref)
     }
 
@@ -47,9 +47,7 @@ impl PySequence {
     /// This is equivalent to the Python expression `self * count`.
     #[inline]
     pub fn repeat(&self, count: usize) -> PyResult<&PySequence> {
-        Bound::borrowed_from_gil_ref(&self)
-            .repeat(count)
-            .map(Bound::into_gil_ref)
+        self.as_borrowed().repeat(count).map(Bound::into_gil_ref)
     }
 
     /// Concatenates `self` and `other`, in place if possible.
@@ -61,8 +59,8 @@ impl PySequence {
     /// possible, but create and return a new object if not.
     #[inline]
     pub fn in_place_concat(&self, other: &PySequence) -> PyResult<&PySequence> {
-        Bound::borrowed_from_gil_ref(&self)
-            .in_place_concat(Bound::borrowed_from_gil_ref(&other))
+        self.as_borrowed()
+            .in_place_concat(&other.as_borrowed())
             .map(Bound::into_gil_ref)
     }
 
@@ -75,7 +73,7 @@ impl PySequence {
     /// possible, but create and return a new object if not.
     #[inline]
     pub fn in_place_repeat(&self, count: usize) -> PyResult<&PySequence> {
-        Bound::borrowed_from_gil_ref(&self)
+        self.as_borrowed()
             .in_place_repeat(count)
             .map(Bound::into_gil_ref)
     }
@@ -85,9 +83,7 @@ impl PySequence {
     /// This is equivalent to the Python expression `self[index]` without support of negative indices.
     #[inline]
     pub fn get_item(&self, index: usize) -> PyResult<&PyAny> {
-        Bound::borrowed_from_gil_ref(&self)
-            .get_item(index)
-            .map(|py2| py2.into_gil_ref())
+        self.as_borrowed().get_item(index).map(Bound::into_gil_ref)
     }
 
     /// Returns the slice of sequence object between `begin` and `end`.
@@ -95,7 +91,7 @@ impl PySequence {
     /// This is equivalent to the Python expression `self[begin:end]`.
     #[inline]
     pub fn get_slice(&self, begin: usize, end: usize) -> PyResult<&PySequence> {
-        Bound::borrowed_from_gil_ref(&self)
+        self.as_borrowed()
             .get_slice(begin, end)
             .map(Bound::into_gil_ref)
     }
@@ -108,7 +104,7 @@ impl PySequence {
     where
         I: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).set_item(i, item)
+        self.as_borrowed().set_item(i, item)
     }
 
     /// Deletes the `i`th element of self.
@@ -116,7 +112,7 @@ impl PySequence {
     /// This is equivalent to the Python statement `del self[i]`.
     #[inline]
     pub fn del_item(&self, i: usize) -> PyResult<()> {
-        Bound::borrowed_from_gil_ref(&self).del_item(i)
+        self.as_borrowed().del_item(i)
     }
 
     /// Assigns the sequence `v` to the slice of `self` from `i1` to `i2`.
@@ -124,7 +120,7 @@ impl PySequence {
     /// This is equivalent to the Python statement `self[i1:i2] = v`.
     #[inline]
     pub fn set_slice(&self, i1: usize, i2: usize, v: &PyAny) -> PyResult<()> {
-        Bound::borrowed_from_gil_ref(&self).set_slice(i1, i2, Bound::borrowed_from_gil_ref(&v))
+        self.as_borrowed().set_slice(i1, i2, &v.as_borrowed())
     }
 
     /// Deletes the slice from `i1` to `i2` from `self`.
@@ -132,7 +128,7 @@ impl PySequence {
     /// This is equivalent to the Python statement `del self[i1:i2]`.
     #[inline]
     pub fn del_slice(&self, i1: usize, i2: usize) -> PyResult<()> {
-        Bound::borrowed_from_gil_ref(&self).del_slice(i1, i2)
+        self.as_borrowed().del_slice(i1, i2)
     }
 
     /// Returns the number of occurrences of `value` in self, that is, return the
@@ -143,7 +139,7 @@ impl PySequence {
     where
         V: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).count(value)
+        self.as_borrowed().count(value)
     }
 
     /// Determines if self contains `value`.
@@ -154,7 +150,7 @@ impl PySequence {
     where
         V: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).contains(value)
+        self.as_borrowed().contains(value)
     }
 
     /// Returns the first index `i` for which `self[i] == value`.
@@ -165,23 +161,19 @@ impl PySequence {
     where
         V: ToPyObject,
     {
-        Bound::borrowed_from_gil_ref(&self).index(value)
+        self.as_borrowed().index(value)
     }
 
     /// Returns a fresh list based on the Sequence.
     #[inline]
     pub fn to_list(&self) -> PyResult<&PyList> {
-        Bound::borrowed_from_gil_ref(&self)
-            .to_list()
-            .map(|py2| py2.into_gil_ref())
+        self.as_borrowed().to_list().map(Bound::into_gil_ref)
     }
 
     /// Returns a fresh tuple based on the Sequence.
     #[inline]
     pub fn to_tuple(&self) -> PyResult<&PyTuple> {
-        Bound::borrowed_from_gil_ref(&self)
-            .to_tuple()
-            .map(|py2| py2.into_gil_ref())
+        self.as_borrowed().to_tuple().map(Bound::into_gil_ref)
     }
 
     /// Register a pyclass as a subclass of `collections.abc.Sequence` (from the Python standard
@@ -541,10 +533,7 @@ impl PyTypeCheck for PySequence {
             || get_sequence_abc(object.py())
                 .and_then(|abc| object.is_instance(abc))
                 .unwrap_or_else(|err| {
-                    err.write_unraisable_bound(
-                        object.py(),
-                        Some(Bound::borrowed_from_gil_ref(&object)),
-                    );
+                    err.write_unraisable_bound(object.py(), Some(&object.as_borrowed()));
                     false
                 })
     }
diff --git a/src/types/string.rs b/src/types/string.rs
index 03d41963f1e..111f3112f26 100644
--- a/src/types/string.rs
+++ b/src/types/string.rs
@@ -5,7 +5,7 @@ use crate::instance::Borrowed;
 use crate::types::any::PyAnyMethods;
 use crate::types::bytes::PyBytesMethods;
 use crate::types::PyBytes;
-use crate::{ffi, Bound, IntoPy, Py, PyAny, PyResult, Python};
+use crate::{ffi, Bound, IntoPy, Py, PyAny, PyNativeType, PyResult, Python};
 use std::borrow::Cow;
 use std::os::raw::c_char;
 use std::str;
@@ -184,7 +184,7 @@ impl PyString {
     pub fn to_str(&self) -> PyResult<&str> {
         #[cfg(any(Py_3_10, not(Py_LIMITED_API)))]
         {
-            Borrowed::from_gil_ref(self).to_str()
+            self.as_borrowed().to_str()
         }
 
         #[cfg(not(any(Py_3_10, not(Py_LIMITED_API))))]
@@ -202,7 +202,7 @@ impl PyString {
     /// Returns a `UnicodeEncodeError` if the input is not valid unicode
     /// (containing unpaired surrogates).
     pub fn to_cow(&self) -> PyResult<Cow<'_, str>> {
-        Borrowed::from_gil_ref(self).to_cow()
+        self.as_borrowed().to_cow()
     }
 
     /// Converts the `PyString` into a Rust string.
@@ -210,7 +210,7 @@ impl PyString {
     /// Unpaired surrogates invalid UTF-8 sequences are
     /// replaced with `U+FFFD REPLACEMENT CHARACTER`.
     pub fn to_string_lossy(&self) -> Cow<'_, str> {
-        Borrowed::from_gil_ref(self).to_string_lossy()
+        self.as_borrowed().to_string_lossy()
     }
 
     /// Obtains the raw data backing the Python string.
@@ -229,7 +229,7 @@ impl PyString {
     /// expected on the targets where you plan to distribute your software.
     #[cfg(not(Py_LIMITED_API))]
     pub unsafe fn data(&self) -> PyResult<PyStringData<'_>> {
-        Borrowed::from_gil_ref(self).data()
+        self.as_borrowed().data()
     }
 }
 

From d36ad8f61fdb999b6cc21c9f8fa0e4cfb96db5d6 Mon Sep 17 00:00:00 2001
From: David Hewitt <mail@davidhewitt.dev>
Date: Sun, 24 Dec 2023 13:48:13 +0000
Subject: [PATCH 2/2] introduce `Bound::as_borrowed`

---
 src/instance.rs        | 15 ++++++++++-----
 src/types/bytearray.rs |  6 +++---
 src/types/bytes.rs     |  2 +-
 src/types/string.rs    |  8 ++++----
 4 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/src/instance.rs b/src/instance.rs
index 90e672c4fa5..e857efc9889 100644
--- a/src/instance.rs
+++ b/src/instance.rs
@@ -197,6 +197,15 @@ impl<'py, T> Bound<'py, T> {
         self.into_non_null().as_ptr()
     }
 
+    /// Casts this `Bound<T>` to a `Borrowed<T>` smart pointer.
+    pub fn as_borrowed<'a>(&'a self) -> Borrowed<'a, 'py, T> {
+        Borrowed(
+            unsafe { NonNull::new_unchecked(self.as_ptr()) },
+            PhantomData,
+            self.py(),
+        )
+    }
+
     /// Casts this `Bound<T>` as the corresponding "GIL Ref" type.
     ///
     /// This is a helper to be used for migration from the deprecated "GIL Refs" API.
@@ -300,11 +309,7 @@ impl<'a, 'py> Borrowed<'a, 'py, PyAny> {
 impl<'a, 'py, T> From<&'a Bound<'py, T>> for Borrowed<'a, 'py, T> {
     /// Create borrow on a Bound
     fn from(instance: &'a Bound<'py, T>) -> Self {
-        Self(
-            unsafe { NonNull::new_unchecked(instance.as_ptr()) },
-            PhantomData,
-            instance.py(),
-        )
+        instance.as_borrowed()
     }
 }
 
diff --git a/src/types/bytearray.rs b/src/types/bytearray.rs
index f1b8050c066..2514e987d4d 100644
--- a/src/types/bytearray.rs
+++ b/src/types/bytearray.rs
@@ -400,16 +400,16 @@ impl<'py> PyByteArrayMethods<'py> for Bound<'py, PyByteArray> {
     }
 
     fn data(&self) -> *mut u8 {
-        Borrowed::from(self).data()
+        self.as_borrowed().data()
     }
 
     unsafe fn as_bytes(&self) -> &[u8] {
-        Borrowed::from(self).as_bytes()
+        self.as_borrowed().as_bytes()
     }
 
     #[allow(clippy::mut_from_ref)]
     unsafe fn as_bytes_mut(&self) -> &mut [u8] {
-        Borrowed::from(self).as_bytes_mut()
+        self.as_borrowed().as_bytes_mut()
     }
 
     fn to_vec(&self) -> Vec<u8> {
diff --git a/src/types/bytes.rs b/src/types/bytes.rs
index 5a7b174ea0c..d9d22dbb173 100644
--- a/src/types/bytes.rs
+++ b/src/types/bytes.rs
@@ -107,7 +107,7 @@ pub trait PyBytesMethods<'py> {
 impl<'py> PyBytesMethods<'py> for Bound<'py, PyBytes> {
     #[inline]
     fn as_bytes(&self) -> &[u8] {
-        Borrowed::from(self).as_bytes()
+        self.as_borrowed().as_bytes()
     }
 }
 
diff --git a/src/types/string.rs b/src/types/string.rs
index 111f3112f26..65f5a3922b9 100644
--- a/src/types/string.rs
+++ b/src/types/string.rs
@@ -280,20 +280,20 @@ pub trait PyStringMethods<'py> {
 impl<'py> PyStringMethods<'py> for Bound<'py, PyString> {
     #[cfg(any(Py_3_10, not(Py_LIMITED_API)))]
     fn to_str(&self) -> PyResult<&str> {
-        Borrowed::from(self).to_str()
+        self.as_borrowed().to_str()
     }
 
     fn to_cow(&self) -> PyResult<Cow<'_, str>> {
-        Borrowed::from(self).to_cow()
+        self.as_borrowed().to_cow()
     }
 
     fn to_string_lossy(&self) -> Cow<'_, str> {
-        Borrowed::from(self).to_string_lossy()
+        self.as_borrowed().to_string_lossy()
     }
 
     #[cfg(not(Py_LIMITED_API))]
     unsafe fn data(&self) -> PyResult<PyStringData<'_>> {
-        Borrowed::from(self).data()
+        self.as_borrowed().data()
     }
 }