Merge pull request #889 from kngwyu/refactor-pymethods-inventory

Unify PyMethodsInventoryDispatch and PyMethodsProtocol

Author: kngwyu

CHANGELOG.md

@@ -24,6 +24,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 * `&'static Py~` being allowed as arguments. [#869](https://github.com/PyO3/pyo3/pull/869)
 * `#[pyo3(get)]` for `Py<T>`. [#880](https://github.com/PyO3/pyo3/pull/880)
 
+### Removed
+* `PyMethodsProtocol` is now renamed to `PyMethodsImpl` and hidden. [#889](https://github.com/PyO3/pyo3/pull/889)
+
 
 ## [0.9.2]
 

guide/src/class.md

@@ -63,11 +63,11 @@ impl pyo3::IntoPy<PyObject> for MyClass {
     }
 }
 
-pub struct MyClassGeneratedPyo3Inventory {
+pub struct Pyo3MethodsInventoryForMyClass {
     methods: &'static [pyo3::class::PyMethodDefType],
 }
 
-impl pyo3::class::methods::PyMethodsInventory for MyClassGeneratedPyo3Inventory {
+impl pyo3::class::methods::PyMethodsInventory for Pyo3MethodsInventoryForMyClass {
     fn new(methods: &'static [pyo3::class::PyMethodDefType]) -> Self {
         Self { methods }
     }
@@ -77,11 +77,11 @@ impl pyo3::class::methods::PyMethodsInventory for MyClassGeneratedPyo3Inventory
     }
 }
 
-impl pyo3::class::methods::PyMethodsInventoryDispatch for MyClass {
-    type InventoryType = MyClassGeneratedPyo3Inventory;
+impl pyo3::class::methods::PyMethodsImpl for MyClass {
+    type Methods = Pyo3MethodsInventoryForMyClass;
 }
 
-pyo3::inventory::collect!(MyClassGeneratedPyo3Inventory);
+pyo3::inventory::collect!(Pyo3MethodsInventoryForMyClass);
 # let gil = Python::acquire_gil();
 # let py = gil.python();
 # let cls = py.get_type::<MyClass>();

pyo3-derive-backend/src/pyclass.rs

@@ -213,7 +213,7 @@ fn parse_descriptors(item: &mut syn::Field) -> syn::Result<Vec<FnType>> {
 fn impl_inventory(cls: &syn::Ident) -> TokenStream {
     // Try to build a unique type that gives a hint about it's function when
     // it comes up in error messages
-    let name = cls.to_string() + "GeneratedPyo3Inventory";
+    let name = format!("Pyo3MethodsInventoryFor{}", cls);
     let inventory_cls = syn::Ident::new(&name, Span::call_site());
 
     quote! {
@@ -234,8 +234,8 @@ fn impl_inventory(cls: &syn::Ident) -> TokenStream {
             }
         }
 
-        impl pyo3::class::methods::PyMethodsInventoryDispatch for #cls {
-            type InventoryType = #inventory_cls;
+        impl pyo3::class::methods::PyMethodsImpl for #cls {
+            type Methods = #inventory_cls;
         }
 
         pyo3::inventory::collect!(#inventory_cls);
@@ -461,7 +461,7 @@ fn impl_descriptors(
     Ok(quote! {
         pyo3::inventory::submit! {
             #![crate = pyo3] {
-                type ClsInventory = <#cls as pyo3::class::methods::PyMethodsInventoryDispatch>::InventoryType;
+                type ClsInventory = <#cls as pyo3::class::methods::PyMethodsImpl>::Methods;
                 <ClsInventory as pyo3::class::methods::PyMethodsInventory>::new(&[#(#py_methods),*])
             }
         }

pyo3-derive-backend/src/pyimpl.rs

@@ -33,7 +33,7 @@ pub fn impl_methods(ty: &syn::Type, impls: &mut Vec<syn::ImplItem>) -> syn::Resu
     Ok(quote! {
        pyo3::inventory::submit! {
             #![crate = pyo3] {
-                type TyInventory = <#ty as pyo3::class::methods::PyMethodsInventoryDispatch>::InventoryType;
+                type TyInventory = <#ty as pyo3::class::methods::PyMethodsImpl>::Methods;
                 <TyInventory as pyo3::class::methods::PyMethodsInventory>::new(&[#(
                     #(#cfg_attributes)*
                     #methods

src/class/methods.rs

@@ -115,16 +115,10 @@ impl PySetterDef {
     }
 }
 
-#[doc(hidden)] // Only to be used through the proc macros, use PyMethodsProtocol in custom code
-/// This trait is implemented for all pyclass so to implement the [PyMethodsProtocol]
-/// through inventory
-pub trait PyMethodsInventoryDispatch {
-    /// This allows us to get the inventory type when only the pyclass is in scope
-    type InventoryType: PyMethodsInventory;
-}
-
-#[doc(hidden)] // Only to be used through the proc macros, use PyMethodsProtocol in custom code
-/// Allows arbitrary pymethod blocks to submit their methods, which are eventually collected by pyclass
+/// Implementation detail. Only to be used through the proc macros.
+/// Allows arbitrary pymethod blocks to submit their methods, which are eventually
+/// collected by pyclass.
+#[doc(hidden)]
 pub trait PyMethodsInventory: inventory::Collect {
     /// Create a new instance
     fn new(methods: &'static [PyMethodDefType]) -> Self;
@@ -133,20 +127,16 @@ pub trait PyMethodsInventory: inventory::Collect {
     fn get_methods(&self) -> &'static [PyMethodDefType];
 }
 
-/// The implementation of this trait defines which methods a Python type has.
-///
-/// For pyclass derived structs this is implemented by collecting all impl blocks through inventory
-pub trait PyMethodsProtocol {
-    /// Returns all methods that are defined for a class
-    fn py_methods() -> Vec<&'static PyMethodDefType>;
-}
+/// Implementation detail. Only to be used through the proc macros.
+/// For pyclass derived structs, this trait collects method from all impl blocks using inventory.
+#[doc(hidden)]
+pub trait PyMethodsImpl {
+    /// Normal methods. Mainly defined by `#[pymethod]`.
+    type Methods: PyMethodsInventory;
 
-impl<T> PyMethodsProtocol for T
-where
-    T: PyMethodsInventoryDispatch,
-{
+    /// Returns all methods that are defined for a class.
     fn py_methods() -> Vec<&'static PyMethodDefType> {
-        inventory::iter::<T::InventoryType>
+        inventory::iter::<Self::Methods>
             .into_iter()
             .flat_map(PyMethodsInventory::get_methods)
             .collect()

src/pyclass.rs

@@ -1,5 +1,5 @@
 //! `PyClass` trait
-use crate::class::methods::{PyMethodDefType, PyMethodsProtocol};
+use crate::class::methods::{PyMethodDefType, PyMethodsImpl};
 use crate::pyclass_slots::{PyClassDict, PyClassWeakRef};
 use crate::type_object::{type_flags, PyLayout};
 use crate::{class, ffi, PyCell, PyErr, PyNativeType, PyResult, PyTypeInfo, Python};
@@ -71,7 +71,7 @@ pub unsafe fn tp_free_fallback(obj: *mut ffi::PyObject) {
 /// The `#[pyclass]` attribute automatically implements this trait for your Rust struct,
 /// so you don't have to use this trait directly.
 pub trait PyClass:
-    PyTypeInfo<Layout = PyCell<Self>> + Sized + PyClassAlloc + PyMethodsProtocol
+    PyTypeInfo<Layout = PyCell<Self>> + Sized + PyClassAlloc + PyMethodsImpl
 {
     /// Specify this class has `#[pyclass(dict)]` or not.
     type Dict: PyClassDict;
@@ -215,7 +215,7 @@ fn py_class_flags<T: PyTypeInfo>(type_object: &mut ffi::PyTypeObject) {
     }
 }
 
-fn py_class_method_defs<T: PyMethodsProtocol>() -> (
+fn py_class_method_defs<T: PyMethodsImpl>() -> (
     Option<ffi::newfunc>,
     Option<ffi::PyCFunctionWithKeywords>,
     Vec<ffi::PyMethodDef>,
@@ -274,7 +274,7 @@ fn py_class_async_methods<T>(defs: &mut Vec<ffi::PyMethodDef>) {
     }
 }
 
-fn py_class_properties<T: PyMethodsProtocol>() -> Vec<ffi::PyGetSetDef> {
+fn py_class_properties<T: PyMethodsImpl>() -> Vec<ffi::PyGetSetDef> {
     let mut defs = std::collections::HashMap::new();
 
     for def in T::py_methods() {