Merge pull request #2448 from davidhewitt/frozen

pyclass: switch from immutable to frozen

guide/src/class.md

@@ -951,7 +951,9 @@ unsafe impl ::pyo3::type_object::PyTypeInfo for MyClass {
     }
 }
 
-impl ::pyo3::PyClass for MyClass { }
+impl ::pyo3::PyClass for MyClass {
+    type Frozen = pyo3::pyclass::boolean_struct::False;
+}
 
 impl<'a> ::pyo3::derive_utils::ExtractExt<'a> for &'a mut MyClass {
     type Target = ::pyo3::PyRefMut<'a, MyClass>;
@@ -974,7 +976,6 @@ impl pyo3::impl_::pyclass::PyClassImpl for MyClass {
     type Layout = PyCell<MyClass>;
     type BaseType = PyAny;
     type ThreadChecker = pyo3::impl_::pyclass::ThreadCheckerStub<MyClass>;
-    type Mutability = pyo3::pycell::Mutable;
     type PyClassMutability = pyo3::pycell::MutableClass;
     type Dict = ::pyo3::impl_::pyclass::PyClassDummySlot;
     type WeakRef = ::pyo3::impl_::pyclass::PyClassDummySlot;

pyo3-macros-backend/src/attributes.rs

@@ -15,6 +15,7 @@ pub mod kw {
     syn::custom_keyword!(extends);
     syn::custom_keyword!(freelist);
     syn::custom_keyword!(from_py_with);
+    syn::custom_keyword!(frozen);
     syn::custom_keyword!(gc);
     syn::custom_keyword!(get);
     syn::custom_keyword!(item);
@@ -29,7 +30,6 @@ pub mod kw {
     syn::custom_keyword!(transparent);
     syn::custom_keyword!(unsendable);
     syn::custom_keyword!(weakref);
-    syn::custom_keyword!(immutable);
 }
 
 #[derive(Clone, Debug)]

pyo3-macros-backend/src/pyclass.rs

@@ -61,7 +61,7 @@ pub struct PyClassPyO3Options {
     pub dict: Option<kw::dict>,
     pub extends: Option<ExtendsAttribute>,
     pub freelist: Option<FreelistAttribute>,
-    pub immutable: Option<kw::immutable>,
+    pub frozen: Option<kw::frozen>,
     pub mapping: Option<kw::mapping>,
     pub module: Option<ModuleAttribute>,
     pub name: Option<NameAttribute>,
@@ -78,7 +78,7 @@ enum PyClassPyO3Option {
     Dict(kw::dict),
     Extends(ExtendsAttribute),
     Freelist(FreelistAttribute),
-    Immutable(kw::immutable),
+    Frozen(kw::frozen),
     Mapping(kw::mapping),
     Module(ModuleAttribute),
     Name(NameAttribute),
@@ -101,8 +101,8 @@ impl Parse for PyClassPyO3Option {
             input.parse().map(PyClassPyO3Option::Extends)
         } else if lookahead.peek(attributes::kw::freelist) {
             input.parse().map(PyClassPyO3Option::Freelist)
-        } else if lookahead.peek(attributes::kw::immutable) {
-            input.parse().map(PyClassPyO3Option::Immutable)
+        } else if lookahead.peek(attributes::kw::frozen) {
+            input.parse().map(PyClassPyO3Option::Frozen)
         } else if lookahead.peek(attributes::kw::mapping) {
             input.parse().map(PyClassPyO3Option::Mapping)
         } else if lookahead.peek(attributes::kw::module) {
@@ -160,7 +160,7 @@ impl PyClassPyO3Options {
             PyClassPyO3Option::Dict(dict) => set_option!(dict),
             PyClassPyO3Option::Extends(extends) => set_option!(extends),
             PyClassPyO3Option::Freelist(freelist) => set_option!(freelist),
-            PyClassPyO3Option::Immutable(immutable) => set_option!(immutable),
+            PyClassPyO3Option::Frozen(frozen) => set_option!(frozen),
             PyClassPyO3Option::Mapping(mapping) => set_option!(mapping),
             PyClassPyO3Option::Module(module) => set_option!(module),
             PyClassPyO3Option::Name(name) => set_option!(name),
@@ -713,12 +713,14 @@ impl<'a> PyClassImplsBuilder<'a> {
         let cls = self.cls;
 
         quote! {
-            impl _pyo3::PyClass for #cls { }
+            impl _pyo3::PyClass for #cls {
+                type Frozen = <Self::PyClassMutability as _pyo3::pycell::PyClassMutability>::Frozen;
+            }
         }
     }
     fn impl_extractext(&self) -> TokenStream {
         let cls = self.cls;
-        if self.attr.options.immutable.is_some() {
+        if self.attr.options.frozen.is_some() {
             quote! {
                 impl<'a> _pyo3::derive_utils::ExtractExt<'a> for &'a #cls
                 {
@@ -855,17 +857,7 @@ impl<'a> PyClassImplsBuilder<'a> {
 
         let deprecations = &self.attr.deprecations;
 
-        let mutability = if self.attr.options.immutable.is_some() {
-            quote! {
-                 _pyo3::pycell::Immutable
-            }
-        } else {
-            quote! {
-                _pyo3::pycell::Mutable
-            }
-        };
-
-        let class_mutability = if self.attr.options.immutable.is_some() {
+        let class_mutability = if self.attr.options.frozen.is_some() {
             quote! {
                 ImmutableChild
             }
@@ -907,7 +899,6 @@ impl<'a> PyClassImplsBuilder<'a> {
                 type BaseType = #base;
                 type ThreadChecker = #thread_checker;
                 #inventory
-                type Mutability = #mutability;
                 type PyClassMutability = <<#base as _pyo3::impl_::pyclass::PyClassBaseType>::PyClassMutability as _pyo3::pycell::PyClassMutability>::#class_mutability;
                 type Dict = #dict;
                 type WeakRef = #weakref;

src/class/basic.rs

@@ -10,9 +10,8 @@
 //! [typeobj docs](https://docs.python.org/3/c-api/typeobj.html)
 
 use crate::callback::{HashCallbackOutput, IntoPyCallbackOutput};
-use crate::{
-    exceptions, ffi, pyclass::MutablePyClass, FromPyObject, PyAny, PyCell, PyClass, PyObject,
-};
+use crate::pyclass::boolean_struct::False;
+use crate::{exceptions, ffi, FromPyObject, PyAny, PyCell, PyClass, PyObject};
 use std::os::raw::c_int;
 
 /// Basic Python class customization
@@ -28,14 +27,14 @@ pub trait PyObjectProtocol<'p>: PyClass {
 
     fn __setattr__(&'p mut self, name: Self::Name, value: Self::Value) -> Self::Result
     where
-        Self: PyObjectSetAttrProtocol<'p> + MutablePyClass,
+        Self: PyObjectSetAttrProtocol<'p> + PyClass<Frozen = False>,
     {
         unimplemented!()
     }
 
     fn __delattr__(&'p mut self, name: Self::Name) -> Self::Result
     where
-        Self: PyObjectDelAttrProtocol<'p> + MutablePyClass,
+        Self: PyObjectDelAttrProtocol<'p> + PyClass<Frozen = False>,
     {
         unimplemented!()
     }
@@ -79,12 +78,12 @@ pub trait PyObjectGetAttrProtocol<'p>: PyObjectProtocol<'p> {
     type Name: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<PyObject>;
 }
-pub trait PyObjectSetAttrProtocol<'p>: PyObjectProtocol<'p> + MutablePyClass {
+pub trait PyObjectSetAttrProtocol<'p>: PyObjectProtocol<'p> + PyClass<Frozen = False> {
     type Name: FromPyObject<'p>;
     type Value: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
-pub trait PyObjectDelAttrProtocol<'p>: PyObjectProtocol<'p> + MutablePyClass {
+pub trait PyObjectDelAttrProtocol<'p>: PyObjectProtocol<'p> + PyClass<Frozen = False> {
     type Name: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }

src/class/buffer.rs

@@ -6,7 +6,8 @@
 //! For more information check [buffer protocol](https://docs.python.org/3/c-api/buffer.html)
 //! c-api
 use crate::callback::IntoPyCallbackOutput;
-use crate::{ffi, pyclass::MutablePyClass, PyCell, PyRefMut};
+use crate::pyclass::boolean_struct::False;
+use crate::{ffi, PyCell, PyClass, PyRefMut};
 use std::os::raw::c_int;
 
 /// Buffer protocol interface
@@ -15,7 +16,7 @@ use std::os::raw::c_int;
 /// c-api.
 #[allow(unused_variables)]
 #[deprecated(since = "0.16.0", note = "prefer `#[pymethods]` to `#[pyproto]`")]
-pub trait PyBufferProtocol<'p>: MutablePyClass {
+pub trait PyBufferProtocol<'p>: PyClass<Frozen = False> {
     // No default implementations so that implementors of this trait provide both methods.
 
     fn bf_getbuffer(

src/class/gc.rs

@@ -3,14 +3,15 @@
 
 //! Python GC support
 
-use crate::{ffi, pyclass::MutablePyClass, PyCell};
+use crate::pyclass::boolean_struct::False;
+use crate::{ffi, PyCell, PyClass};
 use std::os::raw::{c_int, c_void};
 
 pub use crate::impl_::pymethods::{PyTraverseError, PyVisit};
 
 /// GC support
 #[deprecated(since = "0.16.0", note = "prefer `#[pymethods]` to `#[pyproto]`")]
-pub trait PyGCProtocol<'p>: MutablePyClass {
+pub trait PyGCProtocol<'p>: PyClass<Frozen = False> {
     fn __traverse__(&'p self, visit: PyVisit<'_>) -> Result<(), PyTraverseError>;
     fn __clear__(&'p mut self);
 }

src/class/mapping.rs

@@ -5,12 +5,13 @@
 //! Trait and support implementation for implementing mapping support
 
 use crate::callback::IntoPyCallbackOutput;
-use crate::{pyclass::MutablePyClass, FromPyObject, PyClass, PyObject};
+use crate::pyclass::boolean_struct::False;
+use crate::{FromPyObject, PyClass, PyObject};
 
 /// Mapping interface
 #[allow(unused_variables)]
 #[deprecated(since = "0.16.0", note = "prefer `#[pymethods]` to `#[pyproto]`")]
-pub trait PyMappingProtocol<'p>: PyClass {
+pub trait PyMappingProtocol<'p>: PyClass<Frozen = False> {
     fn __len__(&'p self) -> Self::Result
     where
         Self: PyMappingLenProtocol<'p>,
@@ -52,13 +53,13 @@ pub trait PyMappingGetItemProtocol<'p>: PyMappingProtocol<'p> {
     type Result: IntoPyCallbackOutput<PyObject>;
 }
 
-pub trait PyMappingSetItemProtocol<'p>: PyMappingProtocol<'p> + MutablePyClass {
+pub trait PyMappingSetItemProtocol<'p>: PyMappingProtocol<'p> + PyClass<Frozen = False> {
     type Key: FromPyObject<'p>;
     type Value: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
 
-pub trait PyMappingDelItemProtocol<'p>: PyMappingProtocol<'p> + MutablePyClass {
+pub trait PyMappingDelItemProtocol<'p>: PyMappingProtocol<'p> + PyClass<Frozen = False> {
     type Key: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }

src/class/number.rs

@@ -5,7 +5,8 @@
 //! Trait and support implementation for implementing number protocol
 use crate::callback::IntoPyCallbackOutput;
 use crate::err::PyErr;
-use crate::{ffi, pyclass::MutablePyClass, FromPyObject, PyClass, PyObject};
+use crate::pyclass::boolean_struct::False;
+use crate::{ffi, FromPyObject, PyClass, PyObject};
 
 /// Number interface
 #[allow(unused_variables)]
@@ -461,76 +462,76 @@ pub trait PyNumberROrProtocol<'p>: PyNumberProtocol<'p> {
     type Result: IntoPyCallbackOutput<PyObject>;
 }
 
-pub trait PyNumberIAddProtocol<'p>: PyNumberProtocol<'p> + MutablePyClass {
+pub trait PyNumberIAddProtocol<'p>: PyNumberProtocol<'p> + PyClass<Frozen = False> {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
 
-pub trait PyNumberISubProtocol<'p>: PyNumberProtocol<'p> + MutablePyClass {
+pub trait PyNumberISubProtocol<'p>: PyNumberProtocol<'p> + PyClass<Frozen = False> {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
 
-pub trait PyNumberIMulProtocol<'p>: PyNumberProtocol<'p> + MutablePyClass {
+pub trait PyNumberIMulProtocol<'p>: PyNumberProtocol<'p> + PyClass<Frozen = False> {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
 
-pub trait PyNumberIMatmulProtocol<'p>: PyNumberProtocol<'p> + MutablePyClass {
+pub trait PyNumberIMatmulProtocol<'p>: PyNumberProtocol<'p> + PyClass<Frozen = False> {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
 
-pub trait PyNumberITruedivProtocol<'p>: PyNumberProtocol<'p> + MutablePyClass {
+pub trait PyNumberITruedivProtocol<'p>: PyNumberProtocol<'p> + PyClass<Frozen = False> {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
 
-pub trait PyNumberIFloordivProtocol<'p>: PyNumberProtocol<'p> + MutablePyClass {
+pub trait PyNumberIFloordivProtocol<'p>: PyNumberProtocol<'p> + PyClass<Frozen = False> {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
 
-pub trait PyNumberIModProtocol<'p>: PyNumberProtocol<'p> + MutablePyClass {
+pub trait PyNumberIModProtocol<'p>: PyNumberProtocol<'p> + PyClass<Frozen = False> {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
 
-pub trait PyNumberIDivmodProtocol<'p>: PyNumberProtocol<'p> + MutablePyClass {
+pub trait PyNumberIDivmodProtocol<'p>: PyNumberProtocol<'p> + PyClass<Frozen = False> {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
 
-pub trait PyNumberIPowProtocol<'p>: PyNumberProtocol<'p> + MutablePyClass {
+pub trait PyNumberIPowProtocol<'p>: PyNumberProtocol<'p> + PyClass<Frozen = False> {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
     // See https://bugs.python.org/issue36379
     type Modulo: FromPyObject<'p>;
 }
 
 #[allow(clippy::upper_case_acronyms)]
-pub trait PyNumberILShiftProtocol<'p>: PyNumberProtocol<'p> + MutablePyClass {
+pub trait PyNumberILShiftProtocol<'p>: PyNumberProtocol<'p> + PyClass<Frozen = False> {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
 
 #[allow(clippy::upper_case_acronyms)]
-pub trait PyNumberIRShiftProtocol<'p>: PyNumberProtocol<'p> + MutablePyClass {
+pub trait PyNumberIRShiftProtocol<'p>: PyNumberProtocol<'p> + PyClass<Frozen = False> {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
 
-pub trait PyNumberIAndProtocol<'p>: PyNumberProtocol<'p> + MutablePyClass {
+pub trait PyNumberIAndProtocol<'p>: PyNumberProtocol<'p> + PyClass<Frozen = False> {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
 
-pub trait PyNumberIXorProtocol<'p>: PyNumberProtocol<'p> + MutablePyClass {
+pub trait PyNumberIXorProtocol<'p>: PyNumberProtocol<'p> + PyClass<Frozen = False> {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
 
-pub trait PyNumberIOrProtocol<'p>: PyNumberProtocol<'p> + MutablePyClass {
+pub trait PyNumberIOrProtocol<'p>: PyNumberProtocol<'p> + PyClass<Frozen = False> {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }

src/class/sequence.rs

@@ -6,7 +6,8 @@
 use crate::callback::IntoPyCallbackOutput;
 use crate::conversion::{FromPyObject, IntoPy};
 use crate::err::PyErr;
-use crate::{exceptions, ffi, pyclass::MutablePyClass, PyAny, PyCell, PyClass, PyObject};
+use crate::pyclass::boolean_struct::False;
+use crate::{exceptions, ffi, PyAny, PyCell, PyClass, PyObject};
 use std::os::raw::c_int;
 
 /// Sequence interface
@@ -89,13 +90,13 @@ pub trait PySequenceGetItemProtocol<'p>: PySequenceProtocol<'p> {
     type Result: IntoPyCallbackOutput<PyObject>;
 }
 
-pub trait PySequenceSetItemProtocol<'p>: PySequenceProtocol<'p> + MutablePyClass {
+pub trait PySequenceSetItemProtocol<'p>: PySequenceProtocol<'p> + PyClass<Frozen = False> {
     type Index: FromPyObject<'p> + From<isize>;
     type Value: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<()>;
 }
 
-pub trait PySequenceDelItemProtocol<'p>: PySequenceProtocol<'p> + MutablePyClass {
+pub trait PySequenceDelItemProtocol<'p>: PySequenceProtocol<'p> + PyClass<Frozen = False> {
     type Index: FromPyObject<'p> + From<isize>;
     type Result: IntoPyCallbackOutput<()>;
 }
@@ -116,14 +117,14 @@ pub trait PySequenceRepeatProtocol<'p>: PySequenceProtocol<'p> {
 }
 
 pub trait PySequenceInplaceConcatProtocol<'p>:
-    PySequenceProtocol<'p> + IntoPy<PyObject> + MutablePyClass
+    PySequenceProtocol<'p> + IntoPy<PyObject> + PyClass<Frozen = False>
 {
     type Other: FromPyObject<'p>;
     type Result: IntoPyCallbackOutput<Self>;
 }
 
 pub trait PySequenceInplaceRepeatProtocol<'p>:
-    PySequenceProtocol<'p> + IntoPy<PyObject> + MutablePyClass + 'p
+    PySequenceProtocol<'p> + IntoPy<PyObject> + PyClass<Frozen = False> + 'p
 {
     type Index: FromPyObject<'p> + From<isize>;
     type Result: IntoPyCallbackOutput<Self>;

src/conversion.rs

@@ -2,11 +2,11 @@
 
 //! Defines conversions between Rust and Python types.
 use crate::err::{self, PyDowncastError, PyResult};
+use crate::pyclass::boolean_struct::False;
 use crate::type_object::PyTypeInfo;
 use crate::types::PyTuple;
 use crate::{
-    ffi, gil, pyclass::MutablePyClass, Py, PyAny, PyCell, PyClass, PyNativeType, PyObject, PyRef,
-    PyRefMut, Python,
+    ffi, gil, Py, PyAny, PyCell, PyClass, PyNativeType, PyObject, PyRef, PyRefMut, Python,
 };
 use std::ptr::NonNull;
 
@@ -375,7 +375,7 @@ where
 
 impl<'a, T> FromPyObject<'a> for PyRefMut<'a, T>
 where
-    T: MutablePyClass,
+    T: PyClass<Frozen = False>,
 {
     fn extract(obj: &'a PyAny) -> PyResult<Self> {
         let cell: &PyCell<T> = PyTryFrom::try_from(obj)?;