Fixed OrderedHash merge bug. New tests for OrderedHash.

lib/mongo/util/ordered_hash.rb

@@ -34,9 +34,20 @@ class OrderedHash < Hash
     @ordered_keys.each { |k| yield k, self[k] }
   end
 
+  def values
+    collect { |k, v| v }
+  end
+
   def merge(other)
+    oh = self.dup
+    oh.merge!(other)
+    oh
+  end
+
+  def merge!(other)
     @ordered_keys ||= []
     @ordered_keys += other.keys # unordered if not an OrderedHash
+    @ordered_keys.uniq!
     super(other)
   end
 

tests/test_ordered_hash.rb

@@ -0,0 +1,82 @@
+$LOAD_PATH[0,0] = File.join(File.dirname(__FILE__), '..', 'lib')
+require 'mongo/util/ordered_hash'
+require 'test/unit'
+
+# NOTE: assumes Mongo is running
+class OrderedHashTest < Test::Unit::TestCase
+
+  def setup
+    @oh = OrderedHash.new
+    @oh['c'] = 1
+    @oh['a'] = 2
+    @oh['z'] = 3
+    @ordered_keys = %w(c a z)
+  end
+
+  def test_empty
+    assert_equal [], OrderedHash.new.keys
+  end
+
+  def test_order_preserved
+    assert_equal @ordered_keys, @oh.keys
+  end
+
+  def test_order_preserved_after_replace
+    @oh['a'] = 42
+    assert_equal @ordered_keys, @oh.keys
+    @oh['c'] = 'foobar'
+    assert_equal @ordered_keys, @oh.keys
+    @oh['z'] = /huh?/
+    assert_equal @ordered_keys, @oh.keys
+  end
+
+  def test_each
+    keys = []
+    @oh.each { |k, v| keys << k }
+    assert_equal keys, @oh.keys
+
+    @oh['z'] = 42
+    assert_equal keys, @oh.keys
+  end
+
+  def test_values
+    assert_equal [1, 2, 3], @oh.values
+  end
+
+  def test_merge
+    other = OrderedHash.new
+    other['f'] = 'foo'
+    noob = @oh.merge(other)
+    assert_equal @ordered_keys + ['f'], noob.keys
+    assert_equal [1, 2, 3, 'foo'], noob.values
+  end
+
+  def test_merge_bang
+    other = OrderedHash.new
+    other['f'] = 'foo'
+    @oh.merge!(other)
+    assert_equal @ordered_keys + ['f'], @oh.keys
+    assert_equal [1, 2, 3, 'foo'], @oh.values
+  end
+
+  def test_merge_bang_with_overlap
+    other = OrderedHash.new
+    other['a'] = 'apple'
+    other['c'] = 'crab'
+    other['f'] = 'foo'
+    @oh.merge!(other)
+    assert_equal @ordered_keys + ['f'], @oh.keys
+    assert_equal ['crab', 'apple', 3, 'foo'], @oh.values
+  end
+
+  def test_merge_bang_with_hash_with_overlap
+    other = Hash.new
+    other['a'] = 'apple'
+    other['c'] = 'crab'
+    other['f'] = 'foo'
+    @oh.merge!(other)
+    assert_equal @ordered_keys + ['f'], @oh.keys
+    assert_equal ['crab', 'apple', 3, 'foo'], @oh.values
+  end
+
+end