RUBY-137 specify index name

lib/mongo/collection.rb

@@ -374,7 +374,7 @@ module Mongo
     #
     # @core indexes create_index-instance_method
     def create_index(spec, opts={})
-      opts.assert_valid_keys(:min, :max, :background, :unique, :dropDups)
+      opts.assert_valid_keys(:min, :max, :name, :background, :unique, :dropDups)
       field_spec = BSON::OrderedHash.new
       if spec.is_a?(String) || spec.is_a?(Symbol)
         field_spec[spec.to_s] = 1
@@ -392,7 +392,7 @@ module Mongo
           "should be either a string, symbol, or an array of arrays."
       end
 
-      name = generate_index_name(field_spec)
+      name = opts.delete(:name) || generate_index_name(field_spec)
 
       selector = {
         :name   => name,

test/collection_test.rb

@@ -626,6 +626,19 @@ class TestCollection < Test::Unit::TestCase
       end
     end
 
+    should "raise an error if index name is greater than 128" do
+      assert_raise Mongo::OperationFailure do
+        @collection.create_index([['a' * 25, 1], ['b' * 25, 1],
+          ['c' * 25, 1], ['d' * 25, 1], ['e' * 25, 1]])
+      end
+    end
+
+    should "allow for an alternate name to be specified" do
+      @collection.create_index([['a' * 25, 1], ['b' * 25, 1],
+        ['c' * 25, 1], ['d' * 25, 1], ['e' * 25, 1]], :name => 'foo_index')
+      assert @collection.index_information['foo_index']
+    end
+
     should "generate indexes in the proper order" do
       @collection.expects(:insert_documents) do |sel, coll, safe|
         assert_equal 'b_1_a_1', sel[:name]