Array#[]= should return assigning value; close #584

src/array.c

@@ -719,24 +719,21 @@ mrb_ary_aset(mrb_state *mrb, mrb_value self)
   mrb_get_args(mrb, "*", &argv, &argc);
   switch(argc) {
   case 2:
-    if (mrb_fixnum_p(argv[0])) {
-      mrb_ary_set(mrb, self, mrb_fixnum(argv[0]), argv[1]);
-    }
-    else {
+    if (!mrb_fixnum_p(argv[0])) {
       /* Should we support Range object for 1st arg ? */
       mrb_raise(mrb, E_TYPE_ERROR, "expected Fixnum for 1st argument");
     }
-    break;
+    mrb_ary_set(mrb, self, mrb_fixnum(argv[0]), argv[1]);
+    return argv[1];
 
   case 3:
     mrb_ary_splice(mrb, self, mrb_fixnum(argv[0]), mrb_fixnum(argv[1]), argv[2]);
-    break;
+    return argv[2];
 
   default:
     mrb_raise(mrb, E_ARGUMENT_ERROR, "wrong number of arguments");
+    return mrb_nil_value();
   }
-
-  return self;
 }
 
 mrb_value

test/t/array.rb

@@ -74,8 +74,8 @@ assert('Array#[]=', '15.2.12.5.5') do
     e3 = e1
   end
 
-  [1,2,3].[]=(1,4) == [1, 4, 3] and
-  [1,2,3].[]=(1,2,3) == [1, 3] and
+  [1,2,3].[]=(1,4) == 4 and
+  [1,2,3].[]=(1,2,3) == 3 and
     e2.class == ArgumentError and
     e3.class == ArgumentError
 end