* array.c (rb_ary_splice): fix r37583 doesn't condier the case when

beg > array length.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@37588 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Fri Nov  9 19:40:03 2012  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* array.c (rb_ary_splice): fix r37583 doesn't condier the case when
+	  beg > array length.
+
 Fri Nov  9 16:11:58 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* random.c (rb_memhash): use siphash.

array.c

@@ -1438,7 +1438,7 @@ rb_ary_splice(VALUE ary, long beg, long len, VALUE rpl)
 	if (beg > ARY_MAX_SIZE - rlen) {
 	    rb_raise(rb_eIndexError, "index %ld too big", beg);
 	}
-	ary_ensure_room_for_push(ary, rlen);
+	ary_ensure_room_for_push(ary, rlen-len); /* len is 0 or negative */
 	len = beg + rlen;
 	rb_mem_clear(RARRAY_PTR(ary) + RARRAY_LEN(ary), beg - RARRAY_LEN(ary));
 	if (rlen > 0) {

test/ruby/test_array.rb

@@ -426,6 +426,18 @@ class TestArray < Test::Unit::TestCase
     a = @cls[1, 2, 3]
     a[-1, 0] = a
     assert_equal([1, 2, 1, 2, 3, 3], a)
+
+    a = @cls[]
+    a[5,0] = [5]
+    assert_equal([nil, nil, nil, nil, nil, 5], a)
+
+    a = @cls[1]
+    a[1,0] = [2]
+    assert_equal([1, 2], a)
+
+    a = @cls[1]
+    a[1,1] = [2]
+    assert_equal([1, 2], a)
   end
 
   def test_assoc