* lib/psych.rb: Fix problem with empty and white-space only strings.

Thanks Peter McLain!
* test/psych/test_psych.rb: tests for change.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@27099 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Tue Mar 30 08:10:59 2010  Aaron Patterson <aaron@tenderlovemaking.com>
+
+	* lib/psych.rb: Fix problem with empty and white-space only strings.
+	  Thanks Peter McLain!
+	* test/psych/test_psych.rb: tests for change.
+
 Tue Mar 30 05:31:39 2010  Aaron Patterson <aaron@tenderlovemaking.com>
 
 	* lib/psych.rb: documentation updates.  Thanks Peter McLain!

lib/psych.rb

@@ -101,7 +101,8 @@ module Psych
   #   Psych.load("--- a")           # => 'a'
   #   Psych.load("---\n - a\n - b") # => ['a', 'b']
   def self.load yaml
-    parse(yaml).to_ruby
+    result = parse(yaml)
+    result ? result.to_ruby : result
   end
 
   ###
@@ -113,7 +114,8 @@ module Psych
   #
   # See Psych::Nodes for more information about YAML AST.
   def self.parse yaml
-    parse_stream(yaml).children.first.children.first
+    children = parse_stream(yaml).children
+    children.empty? ? false : children.first.children.first
   end
 
   ###

test/psych/test_psych.rb

@@ -66,4 +66,11 @@ class TestPsych < Psych::TestCase
 
     assert_equal 'hello world', Psych.parse_file(name).transform
   end
+
+  def test_degenerate_strings
+    assert_equal false, Psych.load('    ')
+    assert_equal false, Psych.parse('   ')
+    assert_equal false, Psych.load('')
+    assert_equal false, Psych.parse('')
+  end
 end