Add sniff for use empty line spacing, fix found occurences

[MAILPOET-2409]

lib/Config/Updater.php

@@ -5,7 +5,6 @@ namespace MailPoet\Config;
 use MailPoet\Services\Bridge;
 use MailPoet\Services\Release\API;
 use MailPoet\Settings\SettingsController;
-
 use MailPoet\WP\Functions as WPFunctions;
 
 class Updater {

lib/Cron/Workers/Bounce.php

@@ -12,6 +12,7 @@ use MailPoet\Services\Bridge\API;
 use MailPoet\Tasks\Bounce as BounceTask;
 use MailPoet\Tasks\Subscribers as TaskSubscribers;
 use MailPoet\Tasks\Subscribers\BatchIterator;
+
 use function MailPoet\Util\array_column;
 
 class Bounce extends SimpleWorker {

lib/Form/Renderer.php

@@ -4,7 +4,6 @@ namespace MailPoet\Form;
 
 use MailPoet\Settings\SettingsController;
 use MailPoet\Subscription\Captcha;
-
 use MailPoet\WP\Functions as WPFunctions;
 
 class Renderer {

lib/Helpscout/Beacon.php

@@ -7,7 +7,6 @@ use MailPoet\Models\Subscriber;
 use MailPoet\Router\Endpoints\CronDaemon;
 use MailPoet\Services\Bridge;
 use MailPoet\Settings\SettingsController;
-
 use MailPoet\WP\Functions as WPFunctions;
 
 class Beacon {

lib/Models/Newsletter.php

@@ -12,6 +12,7 @@ use MailPoet\Util\Security;
 use MailPoet\WooCommerce\Helper as WCHelper;
 use MailPoet\WP\Emoji;
 use MailPoet\WP\Functions as WPFunctions;
+
 use function MailPoet\Util\array_column;
 
 /**

lib/Models/Subscriber.php

@@ -7,6 +7,7 @@ use MailPoet\Settings\SettingsController;
 use MailPoet\Util\Helpers;
 use MailPoet\Util\Security;
 use MailPoet\WP\Functions as WPFunctions;
+
 use function MailPoet\Util\array_column;
 
 /**

lib/Models/SubscriberCustomField.php

@@ -3,6 +3,7 @@
 namespace MailPoet\Models;
 
 use MailPoet\Util\Helpers;
+
 use function MailPoet\Util\array_column;
 
 /**

lib/Segments/SubscribersFinder.php

@@ -7,6 +7,7 @@ use MailPoet\Models\ScheduledTaskSubscriber;
 use MailPoet\Models\Segment;
 use MailPoet\Models\Subscriber;
 use MailPoet\WP\Functions as WPFunctions;
+
 use function MailPoet\Util\array_column;
 
 class SubscribersFinder {

lib/Subscribers/ImportExport/Export/Export.php

@@ -8,6 +8,7 @@ use MailPoet\Subscribers\ImportExport\ImportExportFactory;
 use MailPoet\Util\Security;
 use MailPoet\Util\XLSXWriter;
 use MailPoet\WP\Functions as WPFunctions;
+
 use function MailPoet\Util\array_column;
 
 class Export {

lib/Subscribers/ImportExport/Import/Import.php

@@ -13,6 +13,7 @@ use MailPoet\Subscribers\ImportExport\ImportExportFactory;
 use MailPoet\Subscribers\Source;
 use MailPoet\Util\Helpers;
 use MailPoet\Util\Security;
+
 use function MailPoet\Util\array_column;
 
 class Import {

lib/Tasks/Sending.php

@@ -7,6 +7,7 @@ use MailPoet\Models\ScheduledTask;
 use MailPoet\Models\ScheduledTaskSubscriber;
 use MailPoet\Models\SendingQueue;
 use MailPoet\WP\Functions as WPFunctions;
+
 use function MailPoet\Util\array_column;
 
 /**

lib/Tasks/Subscribers/BatchIterator.php

@@ -3,6 +3,7 @@
 namespace MailPoet\Tasks\Subscribers;
 
 use MailPoet\Models\ScheduledTaskSubscriber;
+
 use function MailPoet\Util\array_column;
 
 class BatchIterator implements \Iterator, \Countable {

lib/Util/Notices/UnauthorizedEmailInNewslettersNotice.php

@@ -10,6 +10,7 @@ use MailPoet\Services\AuthorizedEmailsController;
 use MailPoet\Settings\SettingsController;
 use MailPoet\Util\Helpers;
 use MailPoet\WP\Functions as WPFunctions;
+
 use function MailPoet\Util\array_column;
 
 class UnauthorizedEmailInNewslettersNotice {

tasks/code_sniffer/MailPoet/ruleset.xml

@@ -21,6 +21,13 @@
   <rule ref="SlevomatCodingStandard.Namespaces.DisallowGroupUse"/>
   <rule ref="SlevomatCodingStandard.Namespaces.UselessAlias"/>
   <rule ref="SlevomatCodingStandard.Namespaces.AlphabeticallySortedUses"/>
+  <rule ref="SlevomatCodingStandard.Namespaces.UseSpacing">
+    <properties>
+      <property name="linesCountBeforeFirstUse" value="1" />
+      <property name="linesCountAfterLastUse" value="1" />
+      <property name="linesCountBetweenUseTypes" value="1" />
+    </properties>
+  </rule>
 
   <!-- checks for unused methods, unused or write-only properties in a class and unused private constants -->
   <rule ref="SlevomatCodingStandard.Classes.UnusedPrivateElements"/>

tests/integration/Subscribers/NewSubscriberNotificationMailerTest.php

@@ -8,7 +8,6 @@ use MailPoet\Mailer\Mailer;
 use MailPoet\Models\Segment;
 use MailPoet\Models\Setting;
 use MailPoet\Models\Subscriber;
-
 use MailPoet\Settings\SettingsController;
 
 class NewSubscriberNotificationMailerTest extends \MailPoetTest {