Use `Primitive.mandatory_only?` for `Array#sample`

array.c

@@ -6337,7 +6337,7 @@ rb_ary_shuffle(rb_execution_context_t *ec, VALUE ary, VALUE randgen)
 }
 
 static VALUE
-rb_ary_sample(rb_execution_context_t *ec, VALUE ary, VALUE randgen, VALUE nv, VALUE to_array)
+ary_sample(rb_execution_context_t *ec, VALUE ary, VALUE randgen, VALUE nv, VALUE to_array)
 {
     VALUE result;
     long n, len, i, j, k, idx[10];
@@ -6466,6 +6466,12 @@ rb_ary_sample(rb_execution_context_t *ec, VALUE ary, VALUE randgen, VALUE nv, VA
     return result;
 }
 
+static VALUE
+ary_sample0(rb_execution_context_t *ec, VALUE ary)
+{
+    return ary_sample(ec, ary, rb_cRandom, Qfalse, Qfalse);
+}
+
 static VALUE
 rb_ary_cycle_size(VALUE self, VALUE args, VALUE eobj)
 {

array.rb

@@ -58,6 +58,12 @@ class Array
   #    a.sample(random: Random.new(1))     #=> 6
   #    a.sample(4, random: Random.new(1))  #=> [6, 10, 9, 2]
   def sample(n = (ary = false), random: Random)
-    Primitive.rb_ary_sample(random, n, ary)
+    if Primitive.mandatory_only?
+      # Primitive.cexpr! %{ rb_ary_sample(self, rb_cRandom, Qfalse, Qfalse) }
+      Primitive.ary_sample0
+    else
+      # Primitive.cexpr! %{ rb_ary_sample(self, random, n, ary) }
+      Primitive.ary_sample(random, n, ary)
+    end
   end
 end