Merged test case to check writeonly properties

Author: TD22057

include/pybind11/pybind11.h

@@ -1174,6 +1174,14 @@ class class_ : public detail::generic_type {
         return *this;
     }
 
+    template <typename C, typename D, typename... Extra>
+    class_ &def_writeonly(const char *name, D C::*pm, const Extra& ...extra) {
+        static_assert(std::is_base_of<C, type>::value, "def_writeonly() requires a class member (or base class member)");
+        cpp_function fset([pm](type &c, const D &value) { c.*pm = value; }, is_method(*this));
+        def_property_writeonly(name, fset, extra...);
+        return *this;
+    }
+
     template <typename D, typename... Extra>
     class_ &def_readwrite_static(const char *name, D *pm, const Extra& ...extra) {
         cpp_function fget([pm](object) -> const D &{ return *pm; }, scope(*this)),
@@ -1189,31 +1197,58 @@ class class_ : public detail::generic_type {
         return *this;
     }
 
+    template <typename D, typename... Extra>
+    class_ &def_writeonly_static(const char *name, D *pm, const Extra& ...extra) {
+        cpp_function fset([pm](object, const D &value) { *pm = value; }, scope(*this));
+        def_property_writeonly_static(name, fset, extra...);
+        return *this;
+    }
+
     /// Uses return_value_policy::reference_internal by default
     template <typename Getter, typename... Extra>
     class_ &def_property_readonly(const char *name, const Getter &fget, const Extra& ...extra) {
         return def_property_readonly(name, cpp_function(method_adaptor<type>(fget)),
                                      return_value_policy::reference_internal, extra...);
     }
 
+    template <typename Setter, typename... Extra>
+    class_ &def_property_writeonly(const char *name, const Setter &fset, const Extra& ...extra) {
+        return def_property_writeonly(name, cpp_function(method_adaptor<type>(fset)),extra...);
+    }
+
     /// Uses cpp_function's return_value_policy by default
     template <typename... Extra>
     class_ &def_property_readonly(const char *name, const cpp_function &fget, const Extra& ...extra) {
         return def_property(name, fget, cpp_function(), extra...);
     }
 
+    template <typename... Extra>
+    class_ &def_property_writeonly(const char *name, const cpp_function &fset, const Extra& ...extra) {
+        return def_property(name, cpp_function(), fset, extra...);
+    }
+
     /// Uses return_value_policy::reference by default
     template <typename Getter, typename... Extra>
     class_ &def_property_readonly_static(const char *name, const Getter &fget, const Extra& ...extra) {
         return def_property_readonly_static(name, cpp_function(fget), return_value_policy::reference, extra...);
     }
 
+    template <typename Setter, typename... Extra>
+    class_ &def_property_writeonly_static(const char *name, const Setter &fset, const Extra& ...extra) {
+        return def_property_writeonly_static(name, cpp_function(fset), extra...);
+    }
+
     /// Uses cpp_function's return_value_policy by default
     template <typename... Extra>
     class_ &def_property_readonly_static(const char *name, const cpp_function &fget, const Extra& ...extra) {
         return def_property_static(name, fget, cpp_function(), extra...);
     }
 
+    template <typename... Extra>
+    class_ &def_property_writeonly_static(const char *name, const cpp_function &fset, const Extra& ...extra) {
+        return def_property_static(name, cpp_function(), fset, extra...);
+    }
+
     /// Uses return_value_policy::reference_internal by default
     template <typename Getter, typename Setter, typename... Extra>
     class_ &def_property(const char *name, const Getter &fget, const Setter &fset, const Extra& ...extra) {