Add static method support to ClassDB

* Based on the work done for Variant in the past.
* Added `ClassDB::bind_static_method`
* Cleaned up ClassDB::bind_method to use variadic templates.

This adds support for having static methods in Object derived classes.
Note that this does not make it work yet in GDScript or Mono and, while it works for GDExtension, GodotCPP needs to be updated.

1 files changed, 18 insertions, 66 deletions

diff --git a/core/object/class_db.h b/core/object/class_db.h
index 32e4bf7644..4211601d15 100644
--- a/core/object/class_db.h
+++ b/core/object/class_db.h
@@ -227,75 +227,27 @@ public:
 
 	static uint64_t get_api_hash(APIType p_api);
 
-	template <class N, class M>
-	static MethodBind *bind_method(N p_method_name, M p_method) {
-		MethodBind *bind = create_method_bind(p_method);
-
-		return bind_methodfi(METHOD_FLAGS_DEFAULT, bind, p_method_name, nullptr, 0); //use static function, much smaller binary usage
-	}
-
-	template <class N, class M>
-	static MethodBind *bind_method(N p_method_name, M p_method, const Variant &p_def1) {
-		MethodBind *bind = create_method_bind(p_method);
-		const Variant *ptr[1] = { &p_def1 };
-
-		return bind_methodfi(METHOD_FLAGS_DEFAULT, bind, p_method_name, ptr, 1);
-	}
-
-	template <class N, class M>
-	static MethodBind *bind_method(N p_method_name, M p_method, const Variant &p_def1, const Variant &p_def2) {
-		MethodBind *bind = create_method_bind(p_method);
-		const Variant *ptr[2] = { &p_def1, &p_def2 };
-
-		return bind_methodfi(METHOD_FLAGS_DEFAULT, bind, p_method_name, ptr, 2);
-	}
-
-	template <class N, class M>
-	static MethodBind *bind_method(N p_method_name, M p_method, const Variant &p_def1, const Variant &p_def2, const Variant &p_def3) {
-		MethodBind *bind = create_method_bind(p_method);
-		const Variant *ptr[3] = { &p_def1, &p_def2, &p_def3 };
-
-		return bind_methodfi(METHOD_FLAGS_DEFAULT, bind, p_method_name, ptr, 3);
-	}
-
-	template <class N, class M>
-	static MethodBind *bind_method(N p_method_name, M p_method, const Variant &p_def1, const Variant &p_def2, const Variant &p_def3, const Variant &p_def4) {
-		MethodBind *bind = create_method_bind(p_method);
-		const Variant *ptr[4] = { &p_def1, &p_def2, &p_def3, &p_def4 };
-
-		return bind_methodfi(METHOD_FLAGS_DEFAULT, bind, p_method_name, ptr, 4);
-	}
-
-	template <class N, class M>
-	static MethodBind *bind_method(N p_method_name, M p_method, const Variant &p_def1, const Variant &p_def2, const Variant &p_def3, const Variant &p_def4, const Variant &p_def5) {
-		MethodBind *bind = create_method_bind(p_method);
-		const Variant *ptr[5] = { &p_def1, &p_def2, &p_def3, &p_def4, &p_def5 };
-
-		return bind_methodfi(METHOD_FLAGS_DEFAULT, bind, p_method_name, ptr, 5);
-	}
-
-	template <class N, class M>
-	static MethodBind *bind_method(N p_method_name, M p_method, const Variant &p_def1, const Variant &p_def2, const Variant &p_def3, const Variant &p_def4, const Variant &p_def5, const Variant &p_def6) {
-		MethodBind *bind = create_method_bind(p_method);
-		const Variant *ptr[6] = { &p_def1, &p_def2, &p_def3, &p_def4, &p_def5, &p_def6 };
-
-		return bind_methodfi(METHOD_FLAGS_DEFAULT, bind, p_method_name, ptr, 6);
-	}
-
-	template <class N, class M>
-	static MethodBind *bind_method(N p_method_name, M p_method, const Variant &p_def1, const Variant &p_def2, const Variant &p_def3, const Variant &p_def4, const Variant &p_def5, const Variant &p_def6, const Variant &p_def7) {
+	template <class N, class M, typename... VarArgs>
+	static MethodBind *bind_method(N p_method_name, M p_method, VarArgs... p_args) {
+		Variant args[sizeof...(p_args) + 1] = { p_args..., Variant() }; // +1 makes sure zero sized arrays are also supported.
+		const Variant *argptrs[sizeof...(p_args) + 1];
+		for (uint32_t i = 0; i < sizeof...(p_args); i++) {
+			argptrs[i] = &args[i];
+		}
 		MethodBind *bind = create_method_bind(p_method);
-		const Variant *ptr[7] = { &p_def1, &p_def2, &p_def3, &p_def4, &p_def5, &p_def6, &p_def7 };
-
-		return bind_methodfi(METHOD_FLAGS_DEFAULT, bind, p_method_name, ptr, 7);
+		return bind_methodfi(METHOD_FLAGS_DEFAULT, bind, p_method_name, sizeof...(p_args) == 0 ? nullptr : (const Variant **)argptrs, sizeof...(p_args));
 	}
 
-	template <class N, class M>
-	static MethodBind *bind_method(N p_method_name, M p_method, const Variant &p_def1, const Variant &p_def2, const Variant &p_def3, const Variant &p_def4, const Variant &p_def5, const Variant &p_def6, const Variant &p_def7, const Variant &p_def8) {
-		MethodBind *bind = create_method_bind(p_method);
-		const Variant *ptr[8] = { &p_def1, &p_def2, &p_def3, &p_def4, &p_def5, &p_def6, &p_def7, &p_def8 };
-
-		return bind_methodfi(METHOD_FLAGS_DEFAULT, bind, p_method_name, ptr, 8);
+	template <class N, class M, typename... VarArgs>
+	static MethodBind *bind_static_method(const StringName &p_class, N p_method_name, M p_method, VarArgs... p_args) {
+		Variant args[sizeof...(p_args) + 1] = { p_args..., Variant() }; // +1 makes sure zero sized arrays are also supported.
+		const Variant *argptrs[sizeof...(p_args) + 1];
+		for (uint32_t i = 0; i < sizeof...(p_args); i++) {
+			argptrs[i] = &args[i];
+		}
+		MethodBind *bind = create_static_method_bind(p_method);
+		bind->set_instance_class(p_class);
+		return bind_methodfi(METHOD_FLAGS_DEFAULT, bind, p_method_name, sizeof...(p_args) == 0 ? nullptr : (const Variant **)argptrs, sizeof...(p_args));
 	}
 
 	template <class M>