stubgen.py: handle method aliases similarly to function aliases

Author: wojdyr

src/stubgen.py

@@ -376,6 +376,20 @@ def put_nb_func(self, fn: NbFunction, name: Optional[str] = None) -> None:
                 self.write_ln(f"@{overload}")
                 self.put_nb_overload(fn, s, name)
 
+    def put_nb_method(self, fn: NbFunction, name: Optional[str], parent: Optional[object]) -> None:
+        fn_qualname = getattr(fn, "__qualname__", None)
+        if name and fn_qualname:
+            fn_class, _, fn_name = fn_qualname.rpartition('.')
+            # Check if this function is an alias
+            if name != fn_name:
+                if fn_class == getattr(parent, "__qualname__", None):
+                    real_name = fn_name
+                else:
+                    real_name = fn_qualname
+                self.write_ln(f"{name} = {real_name}\n")
+                return
+        self.put_nb_func(fn, name)
+
     def put_function(self, fn: Callable[..., Any], name: Optional[str] = None, parent: Optional[object] = None):
         """Append a function of an arbitrary type to the stub"""
         # Don't generate a constructor for nanobind classes that aren't constructible
@@ -848,7 +862,7 @@ def put(self, value: object, name: Optional[str] = None, parent: Optional[object
             elif tp_mod == "nanobind":
                 if tp_name == "nb_method":
                     value = cast(NbFunction, value)
-                    self.put_nb_func(value, name)
+                    self.put_nb_method(value, name, parent)
                 elif tp_name == "nb_static_property":
                     value = cast(NbStaticProperty, value)
                     self.put_nb_static_property(name, value)

tests/test_typing.cpp

@@ -57,9 +57,10 @@ NB_MODULE(test_typing_ext, m) {
 
     m.def("makeNestedClass", [] { return NestedClass(); });
 
-    // Aliases to local functoins and types
+    // Aliases to functions and types
     m.attr("FooAlias") = m.attr("Foo");
     m.attr("f_alias") = m.attr("f");
+    nb::type<Foo>().attr("lt_alias") = nb::type<Foo>().attr("__lt__");
 
     // Custom signature generation for classes and methods
     struct CustomSignature { int value; };

tests/test_typing_ext.pyi.ref

@@ -32,6 +32,8 @@ class Foo:
 
     def __ge__(self, arg: Foo, /) -> bool: ...
 
+    lt_alias = __lt__
+
 FooAlias: TypeAlias = Foo
 
 T = TypeVar("T", contravariant=True)