1 files changed, 6 insertions, 4 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
index 73aaffc146..17dd71e898 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
@@ -629,11 +629,13 @@ module ActiveRecord
               index_options = options[:where] ? " WHERE #{options[:where]}" : ""
             end
           else
-            message = "Passing a string as third argument of `add_index` is deprecated and will" +
-              " be removed in Rails 4.1." +
-              " Use add_index(#{table_name.inspect}, #{column_name.inspect}, unique: true) instead"
+            if options
+              message = "Passing a string as third argument of `add_index` is deprecated and will" +
+                " be removed in Rails 4.1." +
+                " Use add_index(#{table_name.inspect}, #{column_name.inspect}, unique: true) instead"
 
-            ActiveSupport::Deprecation.warn message
+              ActiveSupport::Deprecation.warn message
+            end
 
             index_type = options
           end