Do not return backends but add a method to check for one

lib/private/group/manager.php

@@ -98,10 +98,21 @@ class Manager extends PublicEmitter implements IGroupManager {
 	}
 
 	/**
-	 * @return \OC_Group_Backend[] Get registered backends
+	 * Checks whether a given backend is used
+	 *
+	 * @param string $backendClass Full classname including complete namespace
+	 * @return bool
 	 */
-	public function getBackends() {
-		return $this->backends;
+	public function isBackendUsed($backendClass) {
+		$backendClass = strtolower(ltrim($backendClass, '\\'));
+
+		foreach ($this->backends as $backend) {
+			if (strtolower(get_class($backend)) === $backendClass) {
+				return true;
+			}
+		}
+
+		return false;
 	}
 
 	/**

lib/public/igroupmanager.php

@@ -41,10 +41,13 @@ namespace OCP;
  */
 interface IGroupManager {
 	/**
-	 * @return \OC_Group_Backend[] Get registered backends
+	 * Checks whether a given backend is used
+	 *
+	 * @param string $backendClass Full classname including complete namespace
+	 * @return bool
 	 * @since 8.1.0
 	 */
-	public function getBackends();
+	public function isBackendUsed($backendClass);
 
 	/**
 	 * @param \OCP\UserInterface $backend

settings/users.php

@@ -41,12 +41,10 @@ $groupManager = \OC_Group::getManager();
 $sortGroupsBy = \OC\Group\MetaData::SORT_USERCOUNT;
 
 if (class_exists('\OCA\user_ldap\GROUP_LDAP')) {
-	$backends = $groupManager->getBackends();
-	foreach ($backends as $backend) {
-		if ($backend instanceof \OCA\user_ldap\GROUP_LDAP) {
-			// LDAP user count can be slow, so we sort by gorup name here
-			$sortGroupsBy = \OC\Group\MetaData::SORT_GROUPNAME;
-		}
+	$isLDAPUsed = $groupManager->isBackendUsed('\OCA\user_ldap\GROUP_LDAP');
+	if ($isLDAPUsed) {
+		// LDAP user count can be slow, so we sort by group name here
+		$sortGroupsBy = \OC\Group\MetaData::SORT_GROUPNAME;
 	}
 }