Raise the same error as CRuby when rb_define_method argc is invalid

Author: eregon

lib/truffle/truffle/cext_ruby.rb

@@ -15,8 +15,8 @@ module Truffle::CExt
   # methods defined with rb_define_method are normal Ruby methods therefore they cannot be defined in the cext.rb file
   # file because blocks passed as arguments would be skipped by org.truffleruby.cext.CExtNodes.BlockProcNode
   def rb_define_method(mod, name, function, argc)
-    if argc < -2
-      raise "Unsupported rb_define_method argc: #{argc}"
+    if argc < -2 or 15 < argc
+      raise ArgumentError, "arity out of range: #{argc} for -2..15"
     end
 
     method_body = Truffle::Graal.copy_captured_locals -> *args, &block do