diff --git a/object-cache.php b/object-cache.php
index c8ce99c..290d950 100644
--- a/object-cache.php
+++ b/object-cache.php
@@ -1,12 +1,10 @@
 <?php
-/**
- * WP Redis
- *
- * This file needs to be symlinked or copied to wp-content/object-cache.php
- * Users with setups where multiple installs share a common wp-config.php or $table_prefix
- * can use this to guarantee uniqueness for the keys generated by this object cache.
- */
 
+// WP Redis
+// This file needs to be symlinked or copied to wp-content/object-cache.php
+
+// Users with setups where multiple installs share a common wp-config.php or $table_prefix
+// can use this to guarantee uniqueness for the keys generated by this object cache.
 if ( ! defined( 'WP_CACHE_KEY_SALT' ) ) {
 	define( 'WP_CACHE_KEY_SALT', '' );
 }
@@ -183,7 +181,7 @@ function wp_cache_init() {
 	global $wp_object_cache;
 
 	if ( ! ( $wp_object_cache instanceof WP_Object_Cache ) ) {
-		$wp_object_cache = new WP_Object_Cache();
+		$wp_object_cache = new WP_Object_Cache;
 	}
 }
 
@@ -335,83 +333,92 @@ class WP_Object_Cache {
 	 * Holds the cached objects
 	 *
 	 * @var array
+	 * @access private
 	 */
-	public $cache = [];
+	var $cache = array();
 
 	/**
 	 * The amount of times the cache data was already stored in the cache.
 	 *
+	 * @access private
 	 * @var int
 	 */
-	public $cache_hits = 0;
+	var $cache_hits = 0;
 
 	/**
 	 * Amount of times the cache did not have the request in cache
 	 *
 	 * @var int
+	 * @access public
 	 */
-	public $cache_misses = 0;
+	var $cache_misses = 0;
 
 	/**
 	 * The amount of times a request was made to Redis
 	 *
+	 * @access private
 	 * @var int
 	 */
-	public $redis_calls = [];
+	var $redis_calls = array();
 
 	/**
 	 * List of global groups
 	 *
 	 * @var array
+	 * @access protected
 	 */
-	public $global_groups = [];
+	var $global_groups = array();
 
 	/**
 	 * List of non-persistent groups
 	 *
 	 * @var array
+	 * @access protected
 	 */
-	public $non_persistent_groups = [];
+	var $non_persistent_groups = array();
 
 	/**
 	 * List of groups which use Redis hashes.
 	 *
 	 * @var array
+	 * @access protected
 	 */
-	public $redis_hash_groups = [];
+	var $redis_hash_groups = array();
 
 	/**
 	 * The blog prefix to prepend to keys in non-global groups.
 	 *
 	 * @var int
+	 * @access private
 	 */
-	public $blog_prefix;
+	var $blog_prefix;
 
 	/**
 	 * Whether or not Redis is connected
 	 *
 	 * @var bool
+	 * @access private
 	 */
-	public $is_redis_connected = false;
+	var $is_redis_connected = false;
 
 	/**
 	 * Whether or not the object cache thinks Redis needs a flush
 	 *
 	 * @var bool
+	 * @access private
 	 */
-	public $do_redis_failback_flush = false;
+	var $do_redis_failback_flush = false;
 
 	/**
 	 * The last triggered error
-	 *
-	 * @var string
 	 */
-	public $last_triggered_error = '';
+	var $last_triggered_error = '';
 
 	/**
 	 * Whether or not to use true cache groups, instead of flattening.
 	 *
 	 * @var bool
+	 * @access private
 	 */
 	const USE_GROUPS = WP_REDIS_USE_CACHE_GROUPS;
 
@@ -500,7 +507,7 @@ public function decr( $key, $offset = 1, $group = 'default' ) {
 			$group = 'default';
 		}
 
-		// The key needs to exist in order to be decremented.
+		// The key needs to exist in order to be decremented
 		if ( ! $this->_exists( $key, $group ) ) {
 			return false;
 		}
@@ -622,7 +629,7 @@ public function delete_group( $group ) {
 	 * @return bool Always returns true
 	 */
 	public function flush( $redis = true ) {
-		$this->cache = [];
+		$this->cache = array();
 		if ( $redis ) {
 			$this->_call_redis( 'flushdb' );
 		}
@@ -651,14 +658,15 @@ public function get( $key, $group = 'default', $force = false, &$found = null )
 			$group = 'default';
 		}
 
-		// Key is set internally, so we can use this value.
+		// Key is set internally, so we can use this value
 		if ( $this->_isset_internal( $key, $group ) && ! $force ) {
 			$this->cache_hits += 1;
 			$found             = true;
 			return $this->_get_internal( $key, $group );
 		}
 
-		// Not a persistent group, so don't try Redis if the value doesn't exist internally.
+		// Not a persistent group, so don't try Redis if the value doesn't exist
+		// internally
 		if ( ! $this->_should_persist( $group ) ) {
 			$this->cache_misses += 1;
 			$found               = false;
@@ -673,14 +681,14 @@ public function get( $key, $group = 'default', $force = false, &$found = null )
 			$value = $this->_call_redis( 'get', $id );
 		}
 
-		// PhpRedis returns `false` when the key doesn't exist.
+		// PhpRedis returns `false` when the key doesn't exist
 		if ( false === $value ) {
 			$this->cache_misses += 1;
 			$found               = false;
 			return false;
 		}
 
-		// All non-numeric values are serialized.
+		// All non-numeric values are serialized
 		$value = is_numeric( $value ) ? intval( $value ) : unserialize( $value );
 
 		$this->_set_internal( $key, $group, $value );
@@ -703,7 +711,7 @@ public function get_multiple( $keys, $group = 'default', $force = false ) {
 			$group = 'default';
 		}
 
-		$cache = [];
+		$cache = array();
 		if ( ! $this->_should_persist( $group ) ) {
 			foreach ( $keys as $key ) {
 				$cache[ $key ] = $this->_isset_internal( $key, $group ) ? $this->_get_internal( $key, $group ) : false;
@@ -731,7 +739,7 @@ public function get_multiple( $keys, $group = 'default', $force = false ) {
 			$results          = $this->_call_redis( 'hmGet', $redis_safe_group, $remaining_keys );
 			$results          = is_array( $results ) ? array_values( $results ) : $results;
 		} else {
-			$ids = [];
+			$ids = array();
 			foreach ( $remaining_keys as $key ) {
 				$ids[] = $this->_key( $key, $group );
 			}
@@ -741,7 +749,7 @@ public function get_multiple( $keys, $group = 'default', $force = false ) {
 		foreach ( $remaining_keys as $i => $key ) {
 			$value = isset( $results[ $i ] ) ? $results[ $i ] : false;
 			if ( false !== $value ) {
-				// All non-numeric values are serialized.
+				// All non-numeric values are serialized
 				$value = is_numeric( $value ) ? intval( $value ) : unserialize( $value );
 				$this->_set_internal( $key, $group, $value );
 				$this->cache_hits++;
@@ -751,7 +759,7 @@ public function get_multiple( $keys, $group = 'default', $force = false ) {
 			$cache[ $key ] = $value;
 		}
 		// Make sure return values are returned in the order of the passed keys.
-		$return_cache = [];
+		$return_cache = array();
 		foreach ( $keys as $key ) {
 			$return_cache[ $key ] = isset( $cache[ $key ] ) ? $cache[ $key ] : false;
 		}
@@ -772,7 +780,7 @@ public function incr( $key, $offset = 1, $group = 'default' ) {
 			$group = 'default';
 		}
 
-		// The key needs to exist in order to be incremented.
+		// The key needs to exist in order to be incremented
 		if ( ! $this->_exists( $key, $group ) ) {
 			return false;
 		}
@@ -818,7 +826,6 @@ public function incr( $key, $offset = 1, $group = 'default' ) {
 
 	/**
 	 * Replace the contents in the cache, if contents already exist
-	 *
 	 * @see WP_Object_Cache::set()
 	 *
 	 * @param int|string $key What to call the contents in the cache
@@ -888,7 +895,7 @@ public function set( $key, $data, $group = 'default', $expire = WP_REDIS_DEFAULT
 			$data = serialize( $data );
 		}
 
-		// Redis doesn't support expire on hash group keys.
+		// Redis doesn't support expire on hash group keys
 		if ( $this->_should_use_redis_hashes( $group ) ) {
 			$redis_safe_group = $this->_key( '', $group );
 			$this->_call_redis( 'hSet', $redis_safe_group, $key, $data );
@@ -915,7 +922,7 @@ public function stats() {
 		foreach ( $this->redis_calls as $method => $calls ) {
 			$total_redis_calls += $calls;
 		}
-		$out   = [];
+		$out   = array();
 		$out[] = '<p>';
 		$out[] = '<strong>Cache Hits:</strong>' . (int) $this->cache_hits . '<br />';
 		$out[] = '<strong>Cache Misses:</strong>' . (int) $this->cache_misses . '<br />';
@@ -930,7 +937,9 @@ public function stats() {
 			$out[] = '<li><strong>Group:</strong> ' . esc_html( $group ) . ' - ( ' . number_format( strlen( serialize( $cache ) ) / 1024, 2 ) . 'k )</li>';
 		}
 		$out[] = '</ul>';
-		echo implode( PHP_EOL, $out ); // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
+		// @codingStandardsIgnoreStart
+		echo implode( PHP_EOL, $out );
+		// @codingStandardsIgnoreEnd
 	}
 
 	/**
@@ -948,9 +957,6 @@ public function switch_to_blog( $blog_id ) {
 	/**
 	 * Utility function to determine whether a key exists in the cache.
 	 *
-	 * @param string $key The key to check for existence.
-	 * @param string $group The group to which the key belongs.
-	 *
 	 * @access protected
 	 */
 	protected function _exists( $key, $group ) {
@@ -973,8 +979,8 @@ protected function _exists( $key, $group ) {
 	/**
 	 * Check whether there's a value in the internal object cache.
 	 *
-	 * @param string $key The key to check for existence.
-	 * @param string $group The group to which the key belongs.
+	 * @param string $key
+	 * @param string $group
 	 * @return boolean
 	 */
 	protected function _isset_internal( $key, $group ) {
@@ -990,8 +996,8 @@ protected function _isset_internal( $key, $group ) {
 	/**
 	 * Get a value from the internal object cache
 	 *
-	 * @param string $key The key to the value to get.
-	 * @param string $group The group to which the key belongs.
+	 * @param string $key
+	 * @param string $group
 	 * @return mixed
 	 */
 	protected function _get_internal( $key, $group ) {
@@ -1016,15 +1022,15 @@ protected function _get_internal( $key, $group ) {
 	/**
 	 * Set a value to the internal object cache
 	 *
-	 * @param string $key The key to the value to set.
-	 * @param string $group The group to which the key belongs.
-	 * @param mixed $value The value to set.
+	 * @param string $key
+	 * @param string $group
+	 * @param mixed $value
 	 */
 	protected function _set_internal( $key, $group, $value ) {
 		if ( $this->_should_use_redis_hashes( $group ) ) {
 			$multisite_safe_group = $this->multisite && ! isset( $this->global_groups[ $group ] ) ? $this->blog_prefix . $group : $group;
 			if ( ! isset( $this->cache[ $multisite_safe_group ] ) ) {
-				$this->cache[ $multisite_safe_group ] = [];
+				$this->cache[ $multisite_safe_group ] = array();
 			}
 			$this->cache[ $multisite_safe_group ][ $key ] = $value;
 		} else {
@@ -1036,8 +1042,8 @@ protected function _set_internal( $key, $group, $value ) {
 	/**
 	 * Unset a value from the internal object cache
 	 *
-	 * @param string $key The key to the value to unset.
-	 * @param string $group The group to which the key belongs.
+	 * @param string $key
+	 * @param string $group
 	 */
 	protected function _unset_internal( $key, $group ) {
 		if ( $this->_should_use_redis_hashes( $group ) ) {
@@ -1103,7 +1109,7 @@ protected function _should_use_redis_hashes( $group ) {
 	protected function _connect_redis() {
 		global $redis_server;
 
-		$check_dependencies = [ $this, 'check_client_dependencies' ];
+		$check_dependencies = array( $this, 'check_client_dependencies' );
 		/**
 		 * Permits alternate dependency check mechanism to be used.
 		 *
@@ -1119,34 +1125,34 @@ protected function _connect_redis() {
 		$client_parameters = $this->build_client_parameters( $redis_server );
 
 		try {
-			$client_connection = [ $this, 'prepare_client_connection' ];
+			$client_connection = array( $this, 'prepare_client_connection' );
 			/**
 			 * Permits alternate initial client connection mechanism to be used.
 			 *
 			 * @param callable $client_connection Callback to execute.
 			 */
 			$client_connection = apply_filters( 'wp_redis_prepare_client_connection_callback', $client_connection );
-			$this->redis       = call_user_func_array( $client_connection, [ $client_parameters ] );
+			$this->redis       = call_user_func_array( $client_connection, array( $client_parameters ) );
 		} catch ( Exception $e ) {
 			$this->_exception_handler( $e );
 			$this->is_redis_connected = false;
 			return $this->is_redis_connected;
 		}
 
-		$keys_methods = [
+		$keys_methods = array(
 			'auth'     => 'auth',
 			'database' => 'select',
-		];
+		);
 
 		try {
-			$setup_connection = [ $this, 'perform_client_connection' ];
+			$setup_connection = array( $this, 'perform_client_connection' );
 			/**
 			 * Permits alternate setup client connection mechanism to be used.
 			 *
 			 * @param callable $setup_connection Callback to execute.
 			 */
 			$setup_connection = apply_filters( 'wp_redis_perform_client_connection_callback', $setup_connection );
-			call_user_func_array( $setup_connection, [ $this->redis, $client_parameters, $keys_methods ] );
+			call_user_func_array( $setup_connection, array( $this->redis, $client_parameters, $keys_methods ) );
 		} catch ( Exception $e ) {
 			$this->_exception_handler( $e );
 			$this->is_redis_connected = false;
@@ -1185,37 +1191,38 @@ public function build_client_parameters( $redis_server ) {
 		if ( empty( $redis_server ) ) {
 			// Attempt to automatically load Pantheon's Redis config from the env.
 			if ( isset( $_SERVER['CACHE_HOST'] ) ) {
-				$redis_server = [
-					'host' => isset( $_SERVER['CACHE_HOST'] ) ? sanitize_text_field( $_SERVER['CACHE_HOST'] ) : 0,
-					'port' => isset( $_SERVER['CACHE_PORT'] ) ? sanitize_text_field( $_SERVER['CACHE_PORT'] ) : 0,
-					'auth' => isset( $_SERVER['CACHE_PASSWORD'] ) ? sanitize_text_field( $_SERVER['CACHE_PASSWORD'] ) : 0,
-					'database' => isset( $_SERVER['CACHE_DB'] ) ? sanitize_text_field( $_SERVER['CACHE_DB'] ) : 0,
-				];
+				$redis_server = array(
+					'host'     => $_SERVER['CACHE_HOST'],
+					'port'     => $_SERVER['CACHE_PORT'],
+					'auth'     => $_SERVER['CACHE_PASSWORD'],
+					'database' => isset( $_SERVER['CACHE_DB'] ) ? $_SERVER['CACHE_DB'] : 0,
+				);
 			} else {
-				$redis_server = [
-					'host' => '127.0.0.1',
-					'port' => 6379,
+				$redis_server = array(
+					'host'     => '127.0.0.1',
+					'port'     => 6379,
 					'database' => 0,
-				];
+				);
 			}
 		}
 
-		if ( file_exists( $redis_server['host'] ) && 'socket' === filetype( $redis_server['host'] ) ) { // unix socket connection.
-			// port must be null or socket won't connect.
+		if ( file_exists( $redis_server['host'] ) && 'socket' === filetype( $redis_server['host'] ) ) { //unix socket connection
+			//port must be null or socket won't connect
 			$port = null;
-		} else { // tcp connection.
+		} else { //tcp connection
 			$port = ! empty( $redis_server['port'] ) ? $redis_server['port'] : 6379;
 		}
 
-		$defaults = [
-			'host' => $redis_server['host'],
-			'port' => $port,
-			'timeout' => 1000, // I multiplied this by 1000 so we'd have a common measure of ms instead of s and ms, need to make sure this gets divided by 1000.
+		$defaults = array(
+			'host'           => $redis_server['host'],
+			'port'           => $port,
+			'timeout'        => 1000, // I multiplied this by 1000 so we'd have a common measure of ms instead of s and ms, need to make sure this gets divided by 1000
 			'retry_interval' => 100,
-		];
-		// 1s timeout, 100ms delay between reconnections.
+		);
+		// 1s timeout, 100ms delay between reconnections
 
-		// merging the defaults with the original $redis_server enables any custom parameters to get sent downstream to the redis client.
+		// merging the defaults with the original $redis_server enables any
+		// custom parameters to get sent downstream to the redis client.
 		return array_replace_recursive( $redis_server, $defaults );
 	}
 
@@ -1227,15 +1234,16 @@ public function build_client_parameters( $redis_server ) {
 	 */
 	public function prepare_client_connection( $client_parameters ) {
 		if ( defined( 'WP_REDIS_USE_RELAY' ) && WP_REDIS_USE_RELAY ) {
-			$redis = new Relay\Relay();
+			$redis = new Relay\Relay;
 		} else {
-			$redis = new Redis();
+			$redis = new Redis;
 		}
 
 		$redis->connect(
 			$client_parameters['host'],
 			$client_parameters['port'],
-			// $client_parameters['timeout'] is sent in milliseconds, connect() takes seconds, so divide by 1000.
+			// $client_parameters['timeout'] is sent in milliseconds,
+			// connect() takes seconds, so divide by 1000
 			$client_parameters['timeout'] / 1000,
 			null,
 			$client_parameters['retry_interval']
@@ -1251,7 +1259,6 @@ public function prepare_client_connection( $client_parameters ) {
 	 * @param array $client_parameters Parameters used to configure Redis.
 	 * @param array $keys_methods Associative array of keys from
 	 *              $client_parameters to use as method arguments for $redis.
-	 * @throws Exception If the connection fails.
 	 * @return bool True if successful.
 	 */
 	public function perform_client_connection( $redis, $client_parameters, $keys_methods ) {
@@ -1274,17 +1281,17 @@ public function perform_client_connection( $redis, $client_parameters, $keys_met
 	/**
 	 * Wrapper method for calls to Redis, which fails gracefully when Redis is unavailable
 	 *
-	 * @param string $method The name of the Redis method to call.
-	 * @throws Exception If the connection fails.
-	 * @return mixed The return value of the Redis method, or false if Redis is unavailable.
+	 * @param string $method
+	 * @param mixed $args
+	 * @return mixed
 	 */
 	protected function _call_redis( $method ) {
 		global $wpdb;
 
 		$arguments = func_get_args();
-		array_shift( $arguments ); // ignore $method.
+		array_shift( $arguments ); // ignore $method
 
-		// $group is intended for the failback, and isn't passed to the Redis callback.
+		// $group is intended for the failback, and isn't passed to the Redis callback
 		if ( 'hIncrBy' === $method ) {
 			$group = array_pop( $arguments );
 		}
@@ -1295,7 +1302,7 @@ protected function _call_redis( $method ) {
 					$this->redis_calls[ $method ] = 0;
 				}
 				$this->redis_calls[ $method ]++;
-				$retval = call_user_func_array( [ $this->redis, $method ], $arguments );
+				$retval = call_user_func_array( array( $this->redis, $method ), $arguments );
 				return $retval;
 			} catch ( Exception $e ) {
 				$retry_exception_messages = $this->retry_exception_messages();
@@ -1305,16 +1312,17 @@ protected function _call_redis( $method ) {
 
 					$this->_exception_handler( $e );
 
-					// Attempt to refresh the connection if it was successfully established once $this->is_redis_connected will be set inside _connect_redis().
+					// Attempt to refresh the connection if it was successfully established once
+					// $this->is_redis_connected will be set inside _connect_redis()
 					if ( $this->_connect_redis() ) {
-						return call_user_func_array( [ $this, '_call_redis' ], array_merge( [ $method ], $arguments ) );
+						return call_user_func_array( array( $this, '_call_redis' ), array_merge( array( $method ), $arguments ) );
 					}
-					// Fall through to fallback below.
+					// Fall through to fallback below
 				} else {
 					throw $e;
 				}
 			}
-		} // End if.
+		} // End if().
 
 		if ( $this->is_redis_failback_flush_enabled() && ! $this->do_redis_failback_flush && ! empty( $wpdb ) ) {
 			if ( $this->multisite ) {
@@ -1326,11 +1334,13 @@ protected function _call_redis( $method ) {
 				$col1  = 'option_name';
 				$col2  = 'option_value';
 			}
+			// @codingStandardsIgnoreStart
 			$wpdb->query( "INSERT IGNORE INTO {$table} ({$col1},{$col2}) VALUES ('wp_redis_do_redis_failback_flush',1)" );
+			// @codingStandardsIgnoreEnd
 			$this->do_redis_failback_flush = true;
 		}
 
-		// Mock expected behavior from Redis for these methods.
+		// Mock expected behavior from Redis for these methods
 		switch ( $method ) {
 			case 'incr':
 			case 'incrBy':
@@ -1369,7 +1379,7 @@ protected function _call_redis( $method ) {
 	 * @return array Array of expected exception messages
 	 */
 	public function retry_exception_messages() {
-		$retry_exception_messages = [ 'socket error on read socket', 'Connection closed', 'Redis server went away' ];
+		$retry_exception_messages = array( 'socket error on read socket', 'Connection closed', 'Redis server went away' );
 		return apply_filters( 'wp_redis_retry_exception_messages', $retry_exception_messages );
 	}
 
@@ -1407,16 +1417,20 @@ protected function _format_message_for_pattern( $message ) {
 	/**
 	 * Handles exceptions by triggering a php error.
 	 *
-	 * @param Exception $exception The exception to handle.
-	 * @return void
+	 * @param Exception $exception
+	 * @return null
 	 */
 	protected function _exception_handler( $exception ) {
 		try {
 			$this->last_triggered_error = 'WP Redis: ' . $exception->getMessage();
-			// Be friendly to developers debugging production servers by triggering an error.
-			trigger_error( esc_html( $this->last_triggered_error ), E_USER_WARNING ); // phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_trigger_error
-		} catch ( PHPUnit_Framework_Error_Warning $e ) { // phpcs:ignore Generic.CodeAnalysis.EmptyStatement.DetectedCatch
-			// PHPUnit throws an Exception when `trigger_error()` is called. To ensure our tests (which expect Exceptions to be caught) continue to run, we catch the PHPUnit exception and inspect the RedisException message.
+			// Be friendly to developers debugging production servers by triggering an error
+			// @codingStandardsIgnoreStart
+			trigger_error( $this->last_triggered_error, E_USER_WARNING );
+			// @codingStandardsIgnoreEnd
+		} catch ( PHPUnit_Framework_Error_Warning $e ) {
+			// PHPUnit throws an Exception when `trigger_error()` is called.
+			// To ensure our tests (which expect Exceptions to be caught) continue to run,
+			// we catch the PHPUnit exception and inspect the RedisException message
 		}
 	}
 
@@ -1446,6 +1460,8 @@ private function is_redis_failback_flush_enabled() {
 
 	/**
 	 * Sets up object properties; PHP 5 style constructor
+	 *
+	 * @return null|WP_Object_Cache If cache is disabled, returns null.
 	 */
 	public function __construct() {
 		global $blog_id, $table_prefix, $wpdb;
@@ -1454,7 +1470,7 @@ public function __construct() {
 		$this->blog_prefix = $this->multisite ? $blog_id . ':' : '';
 
 		if ( ! $this->_connect_redis() && function_exists( 'add_action' ) ) {
-			add_action( 'admin_notices', [ $this, 'wp_action_admin_notices_warn_missing_redis' ] );
+			add_action( 'admin_notices', array( $this, 'wp_action_admin_notices_warn_missing_redis' ) );
 		}
 
 		if ( $this->is_redis_failback_flush_enabled() && ! empty( $wpdb ) ) {
@@ -1467,11 +1483,15 @@ public function __construct() {
 				$col1  = 'option_name';
 				$col2  = 'option_value';
 			}
+			// @codingStandardsIgnoreStart
 			$this->do_redis_failback_flush = (bool) $wpdb->get_results( "SELECT {$col2} FROM {$table} WHERE {$col1}='wp_redis_do_redis_failback_flush'" );
+			// @codingStandardsIgnoreEnd
 			if ( $this->is_redis_connected && $this->do_redis_failback_flush ) {
 				$ret = $this->_call_redis( 'flushdb' );
 				if ( $ret ) {
+					// @codingStandardsIgnoreStart
 					$wpdb->query( "DELETE FROM {$table} WHERE {$col1}='wp_redis_do_redis_failback_flush'" );
+					// @codingStandardsIgnoreEnd
 					$this->do_redis_failback_flush = false;
 				}
 			}
@@ -1479,8 +1499,11 @@ public function __construct() {
 
 		$this->global_prefix = ( $this->multisite || defined( 'CUSTOM_USER_TABLE' ) && defined( 'CUSTOM_USER_META_TABLE' ) ) ? '' : $table_prefix;
 
-		// @todo This should be moved to the PHP4 style constructor, PHP5
-		register_shutdown_function( [ $this, '__destruct' ] );
+		/**
+		 * @todo This should be moved to the PHP4 style constructor, PHP5
+		 * already calls __destruct()
+		 */
+		register_shutdown_function( array( $this, '__destruct' ) );
 	}
 
 	/**