Refine some magic methods introspection

- __richcmp__ is mapped to le/lt/ge/gt/eq/ne
- __concat__, __repeat__, __inplace_concat__ and __inplace_repeat__ are mapped to their Python equivalent

Author: Tpt

newsfragments/5273.fixed.md

@@ -0,0 +1 @@
+Introspection: Fixes introspection of `__richcmp__`, `__concat__`, `__repeat__`, `__inplace_concat__` and `__inplace_repeat__`

pyo3-macros-backend/src/method.rs

@@ -448,6 +448,7 @@ impl CallingConvention {
     }
 }
 
+#[derive(Clone)]
 pub struct FnSpec<'a> {
     pub tp: FnType,
     // Rust function name

pyo3-macros-backend/src/pyfunction.rs

@@ -96,13 +96,14 @@ pub struct PyFunctionWarningAttribute {
     pub span: Span,
 }
 
-#[derive(PartialEq)]
+#[derive(PartialEq, Clone)]
 pub enum PyFunctionWarningCategory {
     Path(Path),
     UserWarning,
     DeprecationWarning, // TODO: unused for now, intended for pyo3(deprecated) special-case
 }
 
+#[derive(Clone)]
 pub struct PyFunctionWarning {
     pub message: LitStr,
     pub category: PyFunctionWarningCategory,

pyo3-macros-backend/src/pyfunction/signature.rs

@@ -266,7 +266,7 @@ impl ConstructorAttribute {
     }
 }
 
-#[derive(Default)]
+#[derive(Default, Clone)]
 pub struct PythonSignature {
     pub positional_parameters: Vec<String>,
     pub positional_only_parameters: usize,
@@ -286,6 +286,7 @@ impl PythonSignature {
     }
 }
 
+#[derive(Clone)]
 pub struct FunctionSignature<'a> {
     pub arguments: Vec<FnArg<'a>>,
     pub python_signature: PythonSignature,

pyo3-macros-backend/src/pyimpl.rs

@@ -14,7 +14,7 @@ use crate::{
         self, is_proto_method, GeneratedPyMethod, MethodAndMethodDef, MethodAndSlotDef, PyMethod,
     },
 };
-use proc_macro2::TokenStream;
+use proc_macro2::{Ident, TokenStream};
 use quote::{format_ident, quote};
 use syn::ImplItemFn;
 use syn::{
@@ -354,22 +354,34 @@ fn method_introspection_code(spec: &FnSpec<'_>, parent: &syn::Type, ctx: &Ctx) -
     let Ctx { pyo3_path, .. } = ctx;
 
     let name = spec.python_name.to_string();
-    if matches!(
-        name.as_str(),
-        "__richcmp__"
-            | "__concat__"
-            | "__repeat__"
-            | "__inplace_concat__"
-            | "__inplace_repeat__"
-            | "__getbuffer__"
-            | "__releasebuffer__"
-            | "__traverse__"
-            | "__clear__"
-    ) {
-        // This is not a magic Python method, ignore for now
-        // TODO: properly implement
-        return quote! {};
+
+    // __richcmp__ special case
+    if name == "__richcmp__" {
+        // We expend into each individual method
+        return ["__eq__", "__ne__", "__lt__", "__le__", "__gt__", "__ge__"]
+            .into_iter()
+            .map(|method_name| {
+                let mut spec = (*spec).clone();
+                spec.python_name = Ident::new(method_name, spec.python_name.span());
+                // We remove the CompareOp arg, this is safe because the signature is always the same
+                // First the other value to compare with then the CompareOp
+                // We cant to keep the first argument type, hence this hack
+                spec.signature.arguments.pop();
+                spec.signature.python_signature.positional_parameters.pop();
+                method_introspection_code(&spec, parent, ctx)
+            })
+            .collect();
     }
+    // We map or ignore some magic methods
+    // TODO: this might create a naming conflict
+    let name = match name.as_str() {
+        "__concat__" => "__add__".into(),
+        "__repeat__" => "__mul__".into(),
+        "__inplace_concat__" => "__iadd__".into(),
+        "__inplace_repeat__" => "__imul__".into(),
+        "__getbuffer__" | "__releasebuffer__" | "__traverse__" | "__clear__" => return quote! {},
+        _ => name,
+    };
 
     // We introduce self/cls argument and setup decorators
     let mut first_argument = None;

pytests/src/comparisons.rs

@@ -1,3 +1,4 @@
+use pyo3::basic::CompareOp;
 use pyo3::prelude::*;
 
 #[pyclass]
@@ -81,6 +82,21 @@ impl Ordered {
     }
 }
 
+#[pyclass]
+struct OrderedRichCmp(i64);
+
+#[pymethods]
+impl OrderedRichCmp {
+    #[new]
+    fn new(value: i64) -> Self {
+        Self(value)
+    }
+
+    fn __richcmp__(&self, other: &Self, op: CompareOp) -> bool {
+        op.matches(self.0.cmp(&other.0))
+    }
+}
+
 #[pyclass]
 struct OrderedDefaultNe(i64);
 
@@ -113,11 +129,7 @@ impl OrderedDefaultNe {
 }
 
 #[pymodule(gil_used = false)]
-pub fn comparisons(m: &Bound<'_, PyModule>) -> PyResult<()> {
-    m.add_class::<Eq>()?;
-    m.add_class::<EqDefaultNe>()?;
-    m.add_class::<EqDerived>()?;
-    m.add_class::<Ordered>()?;
-    m.add_class::<OrderedDefaultNe>()?;
-    Ok(())
+pub mod comparisons {
+    #[pymodule_export]
+    use super::{Eq, EqDefaultNe, EqDerived, Ordered, OrderedDefaultNe, OrderedRichCmp};
 }

pytests/src/lib.rs

@@ -23,7 +23,9 @@ mod pyo3_pytests {
     use super::*;
 
     #[pymodule_export]
-    use {consts::consts, pyclasses::pyclasses, pyfunctions::pyfunctions};
+    use {
+        comparisons::comparisons, consts::consts, pyclasses::pyclasses, pyfunctions::pyfunctions,
+    };
 
     // Inserting to sys.modules allows importing submodules nicely from Python
     // e.g. import pyo3_pytests.buf_and_str as bas
@@ -32,7 +34,6 @@ mod pyo3_pytests {
         m.add_wrapped(wrap_pymodule!(awaitable::awaitable))?;
         #[cfg(not(Py_LIMITED_API))]
         m.add_wrapped(wrap_pymodule!(buf_and_str::buf_and_str))?;
-        m.add_wrapped(wrap_pymodule!(comparisons::comparisons))?;
         #[cfg(not(Py_LIMITED_API))]
         m.add_wrapped(wrap_pymodule!(datetime::datetime))?;
         m.add_wrapped(wrap_pymodule!(dict_iter::dict_iter))?;

pytests/stubs/comparisons.pyi

@@ -0,0 +1,37 @@
+class Eq:
+    def __eq__(self, /, other: Eq) -> bool: ...
+    def __ne__(self, /, other: Eq) -> bool: ...
+    def __new__(cls, /, value: int) -> None: ...
+
+class EqDefaultNe:
+    def __eq__(self, /, other: EqDefaultNe) -> bool: ...
+    def __new__(cls, /, value: int) -> None: ...
+
+class EqDerived:
+    def __new__(cls, /, value: int) -> None: ...
+
+class Ordered:
+    def __eq__(self, /, other: Ordered) -> bool: ...
+    def __ge__(self, /, other: Ordered) -> bool: ...
+    def __gt__(self, /, other: Ordered) -> bool: ...
+    def __le__(self, /, other: Ordered) -> bool: ...
+    def __lt__(self, /, other: Ordered) -> bool: ...
+    def __ne__(self, /, other: Ordered) -> bool: ...
+    def __new__(cls, /, value: int) -> None: ...
+
+class OrderedDefaultNe:
+    def __eq__(self, /, other: OrderedDefaultNe) -> bool: ...
+    def __ge__(self, /, other: OrderedDefaultNe) -> bool: ...
+    def __gt__(self, /, other: OrderedDefaultNe) -> bool: ...
+    def __le__(self, /, other: OrderedDefaultNe) -> bool: ...
+    def __lt__(self, /, other: OrderedDefaultNe) -> bool: ...
+    def __new__(cls, /, value: int) -> None: ...
+
+class OrderedRichCmp:
+    def __eq__(self, /, other: OrderedRichCmp) -> bool: ...
+    def __ge__(self, /, other: OrderedRichCmp) -> bool: ...
+    def __gt__(self, /, other: OrderedRichCmp) -> bool: ...
+    def __le__(self, /, other: OrderedRichCmp) -> bool: ...
+    def __lt__(self, /, other: OrderedRichCmp) -> bool: ...
+    def __ne__(self, /, other: OrderedRichCmp) -> bool: ...
+    def __new__(cls, /, value: int) -> None: ...

pytests/tests/test_comparisons.py

@@ -8,6 +8,7 @@
     EqDerived,
     Ordered,
     OrderedDefaultNe,
+    OrderedRichCmp,
 )
 from typing_extensions import Self
 
@@ -132,8 +133,10 @@ def __ge__(self, other: Self) -> bool:
         return self.x >= other.x
 
 
-@pytest.mark.parametrize("ty", (Ordered, PyOrdered), ids=("rust", "python"))
-def test_ordered(ty: Type[Union[Ordered, PyOrdered]]):
+@pytest.mark.parametrize(
+    "ty", (Ordered, OrderedRichCmp, PyOrdered), ids=("rust", "rust-richcmp", "python")
+)
+def test_ordered(ty: Type[Union[Ordered, OrderedRichCmp, PyOrdered]]):
     a = ty(0)
     b = ty(0)
     c = ty(1)

src/types/boolobject.rs

@@ -141,6 +141,9 @@ impl<'py> IntoPyObject<'py> for bool {
     type Output = Borrowed<'py, 'py, Self::Target>;
     type Error = Infallible;
 
+    #[cfg(feature = "experimental-inspect")]
+    const OUTPUT_TYPE: &'static str = "bool";
+
     #[inline]
     fn into_pyobject(self, py: Python<'py>) -> Result<Self::Output, Self::Error> {
         Ok(PyBool::new(py, self))
@@ -157,6 +160,9 @@ impl<'py> IntoPyObject<'py> for &bool {
     type Output = Borrowed<'py, 'py, Self::Target>;
     type Error = Infallible;
 
+    #[cfg(feature = "experimental-inspect")]
+    const OUTPUT_TYPE: &'static str = bool::OUTPUT_TYPE;
+
     #[inline]
     fn into_pyobject(self, py: Python<'py>) -> Result<Self::Output, Self::Error> {
         (*self).into_pyobject(py)