* array.c (rb_ary_flatten): flatten(0) works as Array#dup.

  [ruby-core:23168]

* test/ruby/test_array.rb: add a test for above.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@23191 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 5 insertions, 0 deletions

diff --git a/test/ruby/test_array.rb b/test/ruby/test_array.rb
index 92c309241f..9b3dfdf45f 100644
--- a/test/ruby/test_array.rb
+++ b/test/ruby/test_array.rb
@@ -719,6 +719,11 @@ class TestArray < Test::Unit::TestCase
     a7 = a6.flatten
     assert_equal(true, a7.tainted?)
     assert_equal(true, a7.untrusted?)
+
+    a8 = @cls[[1, 2], 3]
+    a9 = a8.flatten(0)
+    assert_equal(a8, a9)
+    assert_not_same(a8, a9)
   end
 
   def test_flatten!