Merge b74f295c9d into 1f8b4a7f1a

include/pybind11/cast.h

@@ -1570,9 +1570,9 @@ class argument_loader {
     using indices = make_index_sequence<sizeof...(Args)>;
 
     template <typename Arg>
-    using argument_is_args = std::is_same<intrinsic_t<Arg>, args>;
+    using argument_is_args = std::is_base_of<args, intrinsic_t<Arg>>;
     template <typename Arg>
-    using argument_is_kwargs = std::is_same<intrinsic_t<Arg>, kwargs>;
+    using argument_is_kwargs = std::is_base_of<kwargs, intrinsic_t<Arg>>;
     // Get kwargs argument position, or -1 if not present:
     static constexpr auto kwargs_pos = constexpr_last<argument_is_kwargs, Args...>();
 

tests/test_kwargs_and_defaults.cpp

@@ -14,6 +14,26 @@
 
 #include <utility>
 
+// Classes needed for subclass test.
+class ArgsSubclass : public py::args {
+    using py::args::args;
+};
+class KWArgsSubclass : public py::kwargs {
+    using py::kwargs::kwargs;
+};
+namespace pybind11 {
+namespace detail {
+template <>
+struct handle_type_name<ArgsSubclass> {
+    static constexpr auto name = const_name("*args");
+};
+template <>
+struct handle_type_name<KWArgsSubclass> {
+    static constexpr auto name = const_name("**kwargs");
+};
+} // namespace detail
+} // namespace pybind11
+
 TEST_SUBMODULE(kwargs_and_defaults, m) {
     auto kw_func
         = [](int x, int y) { return "x=" + std::to_string(x) + ", y=" + std::to_string(y); };
@@ -322,4 +342,10 @@ TEST_SUBMODULE(kwargs_and_defaults, m) {
             py::pos_only{},
             py::arg("i"),
             py::arg("j"));
+
+    // Test support for args and kwargs subclasses
+    m.def("args_kwargs_subclass_function",
+          [](const ArgsSubclass &args, const KWArgsSubclass &kwargs) {
+              return py::make_tuple(args, kwargs);
+          });
 }

tests/test_kwargs_and_defaults.py

@@ -426,3 +426,8 @@ def test_args_refcount():
     assert m.mixed_args_refcount(myval, myval, myval) == (exp3_3, exp3_3, exp3_3)
 
     assert m.class_default_argument() == "<class 'decimal.Decimal'>"
+
+    assert m.args_kwargs_subclass_function(7, 8, myval, a=1, b=myval) == (
+        (7, 8, myval),
+        {"a": 1, "b": myval},
+    )