* ext/psych/lib/psych/visitors/yaml_tree.rb: use YAML 1.0 output

  format for serializing nil values.  Thanks Eric Hodel!
* test/psych/test_nil.rb: test for nil values

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@30459 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 18 insertions, 0 deletions

diff --git a/test/psych/test_nil.rb b/test/psych/test_nil.rb
new file mode 100644
index 0000000000..e63c6c7286
--- /dev/null
+++ b/test/psych/test_nil.rb
@@ -0,0 +1,18 @@
+require_relative 'helper'
+
+module Psych
+  class TestNil < TestCase
+    def test_nil
+      yml = Psych.dump nil
+      assert_equal "--- \n...\n", yml
+      assert_equal nil, Psych.load(yml)
+    end
+
+    def test_array_nil
+      yml = Psych.dump [nil]
+      assert_equal "---\n- \n", yml
+      assert_equal [nil], Psych.load(yml)
+    end
+
+  end
+end