Merge pull request #308 from dpisarewski/neo4j

Description of configuration options for Neo4j and some improvements

README.markdown

@@ -341,6 +341,11 @@ Usage beyond that remains the same with `DatabaseCleaner.start` calling any setu
       <td><code>DatabaseCleaner[:ohm]</code></td>
       <td>Connection specified as Redis URI</td>
     </tr>
+    <tr>
+      <td>Neo4j</td>
+      <td><code>DatabaseCleaner[:neo4j]</code></td>
+      <td>Database type and path(URI) <code>DatabaseCleaner[:neo4j, connection: {type: :server_db, path: 'http://localhost:7475'}].</code></td>
+    </tr>
   </tbody>
 </table>
 
@@ -388,6 +393,19 @@ test:
 
 Due to an inconsistency in JRuby's implementation of Fibers, Sequel gives a different connection to `DatabaseCleaner.start` than is used for tests run between `.start` and `.clean`. This can be worked around by running your tests in a block like `DatabaseCleaner.cleaning { run_my_tests }` instead, which does not use Fibers.
 
+### Model fails to load with Neo4j using transactions
+
+When you are using [neo4j](https://github.com/neo4jrb/neo4j) gem it creates schema and reads indexes upon loading models. These operations can't be done during a transaction. You have to preload your models before DatabaseCleaner starts a transaction.
+
+Add to your rails_helper or spec_helper after requiring database_cleaner:
+
+```ruby
+require 'database_cleaner'
+Dir["#{Rails.root}/app/models/**/*.rb"].each do |model|
+  load model
+end
+```
+
 ## Debugging
 
 In rare cases DatabaseCleaner will encounter errors that it will log.  By default it uses STDOUT set to the ERROR level but you can configure this to use whatever Logger you desire.

examples/lib/neo4j_models.rb

@@ -6,7 +6,7 @@ class Neo4jWidget < Neo4j::Node
   end
 
   def self.count
-    Neo4j::Session.query.pluck('count(*) AS result').first
+    Neo4j::Session.query.match('n').pluck('COUNT(n)').first
   end
 end
 

lib/database_cleaner/neo4j/transaction.rb

@@ -23,9 +23,11 @@ module DatabaseCleaner
       private
 
       def rollback
-        return unless tx
-        tx.failure
-        tx.close
+        if tx
+          tx.failure
+          tx.close
+        end
+      ensure
         self.tx = nil
       end
     end