Allow backend specific repository controllers

Lookin pretty good here, except:

+++ b/includes/controllers.inc
@@ -418,6 +418,30 @@ class VersioncontrolRepositoryController extends VersioncontrolEntityController
+    else {
+      $this->attachCondition($query, 'vcs', array(
+        'values' => array_keys(versioncontrol_get_backends()),
+        'operator' => 'NOT IN',
+      ));
+    }
+    return $query;

Not quite right here - its' not a question of whether the backends exist (they will), it's a question of whether the backends define their own type of repository controller. So we need to check each backend's value for $backend->classesControllers['repo'] == 'VersioncontrolRepositoryController';

+++ b/includes/controllers.inc
@@ -418,6 +418,39 @@ class VersioncontrolRepositoryController extends VersioncontrolEntityController
+      // Add the condition to the query.
+      $this->attachCondition($query, 'vcs', array(
+        'values' => $non_default_backends,
+        'operator' => 'NOT IN',
+      ));

Only attach a condition if $non_default_backends is actually non-empty. Otherwise, we see this fun:

SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '))' at line 1: SELECT base.repo_id AS repo_id, base.name AS name, base.vcs AS vcs, base.root AS root, base.authorization_method AS authorization_method, base.updated AS updated, base.update_method AS update_method, base.locked AS locked, base.data AS data, base.plugins AS plugins FROM {versioncontrol_repositories} base WHERE (base.repo_id IN (:db_condition_placeholder_0)) AND (base.vcs NOT IN ()) ; Array ( [:db_condition_placeholder_0] => 1 )

Yep, passing for me too. Good enough for me, I'm committing this.