diff -r 3d4e9c994f10 -r a86126ab1dd4 wp/wp-admin/includes/class-wp-ms-sites-list-table.php
--- a/wp/wp-admin/includes/class-wp-ms-sites-list-table.php	Tue Oct 22 16:11:46 2019 +0200
+++ b/wp/wp-admin/includes/class-wp-ms-sites-list-table.php	Tue Dec 15 13:49:49 2020 +0100
@@ -62,15 +62,15 @@
 	 *
 	 * @since 3.1.0
 	 *
+	 * @global string $mode List table view mode.
 	 * @global string $s
-	 * @global string $mode
-	 * @global wpdb   $wpdb
+	 * @global wpdb   $wpdb WordPress database abstraction object.
 	 */
 	public function prepare_items() {
-		global $s, $mode, $wpdb;
+		global $mode, $s, $wpdb;
 
 		if ( ! empty( $_REQUEST['mode'] ) ) {
-			$mode = $_REQUEST['mode'] === 'excerpt' ? 'excerpt' : 'list';
+			$mode = 'excerpt' === $_REQUEST['mode'] ? 'excerpt' : 'list';
 			set_user_setting( 'sites_list_mode', $mode );
 		} else {
 			$mode = get_user_setting( 'sites_list_mode', 'list' );
@@ -93,10 +93,12 @@
 		 */
 		if ( ! $s && wp_is_large_network() ) {
 			if ( ! isset( $_REQUEST['orderby'] ) ) {
-				$_GET['orderby'] = $_REQUEST['orderby'] = '';
+				$_GET['orderby']     = '';
+				$_REQUEST['orderby'] = '';
 			}
 			if ( ! isset( $_REQUEST['order'] ) ) {
-				$_GET['order'] = $_REQUEST['order'] = 'DESC';
+				$_GET['order']     = 'DESC';
+				$_REQUEST['order'] = 'DESC';
 			}
 		}
 
@@ -112,7 +114,7 @@
 					preg_match( '/^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.?$/', $s ) ||
 					preg_match( '/^[0-9]{1,3}\.[0-9]{1,3}\.?$/', $s ) ||
 					preg_match( '/^[0-9]{1,3}\.$/', $s ) ) {
-			// IPv4 address
+			// IPv4 address.
 			$sql          = $wpdb->prepare( "SELECT blog_id FROM {$wpdb->registration_log} WHERE {$wpdb->registration_log}.IP LIKE %s", $wpdb->esc_like( $s ) . ( ! empty( $wild ) ? '%' : '' ) );
 			$reg_blog_ids = $wpdb->get_col( $sql );
 
@@ -131,7 +133,7 @@
 
 		$order_by = isset( $_REQUEST['orderby'] ) ? $_REQUEST['orderby'] : '';
 		if ( 'registered' === $order_by ) {
-			// registered is a valid field name.
+			// 'registered' is a valid field name.
 		} elseif ( 'lastupdated' === $order_by ) {
 			$order_by = 'last_updated';
 		} elseif ( 'blogname' === $order_by ) {
@@ -158,6 +160,12 @@
 			$args['no_found_rows'] = false;
 		}
 
+		// Take into account the role the user has selected.
+		$status = isset( $_REQUEST['status'] ) ? wp_unslash( trim( $_REQUEST['status'] ) ) : '';
+		if ( in_array( $status, array( 'public', 'archived', 'mature', 'spam', 'deleted' ), true ) ) {
+			$args[ $status ] = 1;
+		}
+
 		/**
 		 * Filters the arguments for the site query in the sites list table.
 		 *
@@ -200,6 +208,80 @@
 	}
 
 	/**
+	 * Gets links to filter sites by status.
+	 *
+	 * @since 5.3.0
+	 *
+	 * @return array
+	 */
+	protected function get_views() {
+		$counts = wp_count_sites();
+
+		$statuses = array(
+			/* translators: %s: Number of sites. */
+			'all'      => _nx_noop(
+				'All <span class="count">(%s)</span>',
+				'All <span class="count">(%s)</span>',
+				'sites'
+			),
+
+			/* translators: %s: Number of sites. */
+			'public'   => _n_noop(
+				'Public <span class="count">(%s)</span>',
+				'Public <span class="count">(%s)</span>'
+			),
+
+			/* translators: %s: Number of sites. */
+			'archived' => _n_noop(
+				'Archived <span class="count">(%s)</span>',
+				'Archived <span class="count">(%s)</span>'
+			),
+
+			/* translators: %s: Number of sites. */
+			'mature'   => _n_noop(
+				'Mature <span class="count">(%s)</span>',
+				'Mature <span class="count">(%s)</span>'
+			),
+
+			/* translators: %s: Number of sites. */
+			'spam'     => _nx_noop(
+				'Spam <span class="count">(%s)</span>',
+				'Spam <span class="count">(%s)</span>',
+				'sites'
+			),
+
+			/* translators: %s: Number of sites. */
+			'deleted'  => _n_noop(
+				'Deleted <span class="count">(%s)</span>',
+				'Deleted <span class="count">(%s)</span>'
+			),
+		);
+
+		$view_links       = array();
+		$requested_status = isset( $_REQUEST['status'] ) ? wp_unslash( trim( $_REQUEST['status'] ) ) : '';
+		$url              = 'sites.php';
+
+		foreach ( $statuses as $status => $label_count ) {
+			$current_link_attributes = $requested_status === $status || ( '' === $requested_status && 'all' === $status )
+				? ' class="current" aria-current="page"'
+				: '';
+			if ( (int) $counts[ $status ] > 0 ) {
+				$label    = sprintf( translate_nooped_plural( $label_count, $counts[ $status ] ), number_format_i18n( $counts[ $status ] ) );
+				$full_url = 'all' === $status ? $url : add_query_arg( 'status', $status, $url );
+
+				$view_links[ $status ] = sprintf(
+					'<a href="%1$s"%2$s>%3$s</a>',
+					esc_url( $full_url ),
+					$current_link_attributes,
+					$label
+				);
+			}
+		}
+
+		return $view_links;
+	}
+
+	/**
 	 * @return array
 	 */
 	protected function get_bulk_actions() {
@@ -207,8 +289,8 @@
 		if ( current_user_can( 'delete_sites' ) ) {
 			$actions['delete'] = __( 'Delete' );
 		}
-		$actions['spam']    = _x( 'Mark as Spam', 'site' );
-		$actions['notspam'] = _x( 'Not Spam', 'site' );
+		$actions['spam']    = _x( 'Mark as spam', 'site' );
+		$actions['notspam'] = _x( 'Not spam', 'site' );
 
 		return $actions;
 	}
@@ -216,7 +298,7 @@
 	/**
 	 * @global string $mode List table view mode.
 	 *
-	 * @param string $which
+	 * @param string $which The location of the pagination nav markup: 'top' or 'bottom'.
 	 */
 	protected function pagination( $which ) {
 		global $mode;
@@ -229,6 +311,48 @@
 	}
 
 	/**
+	 * Extra controls to be displayed between bulk actions and pagination.
+	 *
+	 * @since 5.3.0
+	 *
+	 * @param string $which The location of the extra table nav markup: 'top' or 'bottom'.
+	 */
+	protected function extra_tablenav( $which ) {
+		?>
+		<div class="alignleft actions">
+		<?php
+		if ( 'top' === $which ) {
+			ob_start();
+
+			/**
+			 * Fires before the Filter button on the MS sites list table.
+			 *
+			 * @since 5.3.0
+			 *
+			 * @param string $which The location of the extra table nav markup: 'top' or 'bottom'.
+			 */
+			do_action( 'restrict_manage_sites', $which );
+			$output = ob_get_clean();
+			if ( ! empty( $output ) ) {
+				echo $output;
+				submit_button( __( 'Filter' ), '', 'filter_action', false, array( 'id' => 'site-query-submit' ) );
+			}
+		}
+		?>
+		</div>
+		<?php
+		/**
+		 * Fires immediately following the closing "actions" div in the tablenav for the
+		 * MS sites list table.
+		 *
+		 * @since 5.3.0
+		 *
+		 * @param string $which The location of the extra table nav markup: 'top' or 'bottom'.
+		 */
+		do_action( 'manage_sites_extra_tablenav', $which );
+	}
+
+	/**
 	 * @return array
 	 */
 	public function get_columns() {
@@ -278,9 +402,10 @@
 			$blogname = untrailingslashit( $blog['domain'] . $blog['path'] );
 			?>
 			<label class="screen-reader-text" for="blog_<?php echo $blog['blog_id']; ?>">
-																	<?php
-																	printf( __( 'Select %s' ), $blogname );
-																	?>
+				<?php
+				/* translators: %s: Site URL. */
+				printf( __( 'Select %s' ), $blogname );
+				?>
 			</label>
 			<input type="checkbox" id="blog_<?php echo $blog['blog_id']; ?>" name="allblogs[]" value="<?php echo esc_attr( $blog['blog_id'] ); ?>" />
 			<?php
@@ -310,41 +435,22 @@
 	public function column_blogname( $blog ) {
 		global $mode;
 
-		$blogname    = untrailingslashit( $blog['domain'] . $blog['path'] );
-		$blog_states = array();
-		reset( $this->status_list );
-
-		foreach ( $this->status_list as $status => $col ) {
-			if ( $blog[ $status ] == 1 ) {
-				$blog_states[] = $col[1];
-			}
-		}
-		$blog_state = '';
-		if ( ! empty( $blog_states ) ) {
-			$state_count = count( $blog_states );
-			$i           = 0;
-			$blog_state .= ' &mdash; ';
-			foreach ( $blog_states as $state ) {
-				++$i;
-				$sep         = ( $i == $state_count ) ? '' : ', ';
-				$blog_state .= "<span class='post-state'>$state$sep</span>";
-			}
-		}
+		$blogname = untrailingslashit( $blog['domain'] . $blog['path'] );
 
 		?>
 		<strong>
 			<a href="<?php echo esc_url( network_admin_url( 'site-info.php?id=' . $blog['blog_id'] ) ); ?>" class="edit"><?php echo $blogname; ?></a>
-			<?php echo $blog_state; ?>
+			<?php $this->site_states( $blog ); ?>
 		</strong>
 		<?php
 		if ( 'list' !== $mode ) {
 			switch_to_blog( $blog['blog_id'] );
 			echo '<p>';
 			printf(
-				/* translators: 1: site name, 2: site tagline. */
+				/* translators: 1: Site title, 2: Site tagline. */
 				__( '%1$s &#8211; %2$s' ),
 				get_option( 'blogname' ),
-				'<em>' . get_option( 'blogdescription ' ) . '</em>'
+				'<em>' . get_option( 'blogdescription' ) . '</em>'
 			);
 			echo '</p>';
 			restore_current_blog();
@@ -369,7 +475,7 @@
 			$date = __( 'Y/m/d g:i:s a' );
 		}
 
-		echo ( $blog['last_updated'] === '0000-00-00 00:00:00' ) ? __( 'Never' ) : mysql2date( $date, $blog['last_updated'] );
+		echo ( '0000-00-00 00:00:00' === $blog['last_updated'] ) ? __( 'Never' ) : mysql2date( $date, $blog['last_updated'] );
 	}
 
 	/**
@@ -390,7 +496,7 @@
 			$date = __( 'Y/m/d g:i:s a' );
 		}
 
-		if ( $blog['registered'] === '0000-00-00 00:00:00' ) {
+		if ( '0000-00-00 00:00:00' === $blog['registered'] ) {
 			echo '&#x2014;';
 		} else {
 			echo mysql2date( $date, $blog['registered'] );
@@ -469,7 +575,7 @@
 	}
 
 	/**
-	 * @global string $mode
+	 * @global string $mode List table view mode.
 	 */
 	public function display_rows() {
 		foreach ( $this->items as $blog ) {
@@ -478,7 +584,7 @@
 			reset( $this->status_list );
 
 			foreach ( $this->status_list as $status => $col ) {
-				if ( $blog[ $status ] == 1 ) {
+				if ( 1 == $blog[ $status ] ) {
 					$class = " class='{$col[0]}'";
 				}
 			}
@@ -492,6 +598,55 @@
 	}
 
 	/**
+	 * Maybe output comma-separated site states.
+	 *
+	 * @since 5.3.0
+	 *
+	 * @param array $site
+	 */
+	protected function site_states( $site ) {
+		$site_states = array();
+
+		// $site is still an array, so get the object.
+		$_site = WP_Site::get_instance( $site['blog_id'] );
+
+		if ( is_main_site( $_site->id ) ) {
+			$site_states['main'] = __( 'Main' );
+		}
+
+		reset( $this->status_list );
+
+		$site_status = isset( $_REQUEST['status'] ) ? wp_unslash( trim( $_REQUEST['status'] ) ) : '';
+		foreach ( $this->status_list as $status => $col ) {
+			if ( ( 1 === intval( $_site->{$status} ) ) && ( $site_status !== $status ) ) {
+				$site_states[ $col[0] ] = $col[1];
+			}
+		}
+
+		/**
+		 * Filter the default site display states for items in the Sites list table.
+		 *
+		 * @since 5.3.0
+		 *
+		 * @param array $site_states An array of site states. Default 'Main',
+		 *                           'Archived', 'Mature', 'Spam', 'Deleted'.
+		 * @param WP_Site $site The current site object.
+		 */
+		$site_states = apply_filters( 'display_site_states', $site_states, $_site );
+
+		if ( ! empty( $site_states ) ) {
+			$state_count = count( $site_states );
+			$i           = 0;
+			echo ' &mdash; ';
+			foreach ( $site_states as $state ) {
+				++$i;
+				( $i == $state_count ) ? $sep = '' : $sep = ', ';
+				echo "<span class='post-state'>{$state}{$sep}</span>";
+			}
+		}
+	}
+
+	/**
 	 * Gets the name of the default primary column.
 	 *
 	 * @since 4.3.0
@@ -510,11 +665,12 @@
 	 * @param object $blog        Site being acted upon.
 	 * @param string $column_name Current column name.
 	 * @param string $primary     Primary column name.
-	 * @return string Row actions output.
+	 * @return string Row actions output for sites in Multisite, or an empty string
+	 *                if the current column is not the primary column.
 	 */
 	protected function handle_row_actions( $blog, $column_name, $primary ) {
 		if ( $primary !== $column_name ) {
-			return;
+			return '';
 		}
 
 		$blogname = untrailingslashit( $blog['domain'] . $blog['path'] );
@@ -536,19 +692,19 @@
 		$actions['edit']    = '<a href="' . esc_url( network_admin_url( 'site-info.php?id=' . $blog['blog_id'] ) ) . '">' . __( 'Edit' ) . '</a>';
 		$actions['backend'] = "<a href='" . esc_url( get_admin_url( $blog['blog_id'] ) ) . "' class='edit'>" . __( 'Dashboard' ) . '</a>';
 		if ( get_network()->site_id != $blog['blog_id'] ) {
-			if ( $blog['deleted'] == '1' ) {
+			if ( '1' == $blog['deleted'] ) {
 				$actions['activate'] = '<a href="' . esc_url( wp_nonce_url( network_admin_url( 'sites.php?action=confirm&amp;action2=activateblog&amp;id=' . $blog['blog_id'] ), 'activateblog_' . $blog['blog_id'] ) ) . '">' . __( 'Activate' ) . '</a>';
 			} else {
 				$actions['deactivate'] = '<a href="' . esc_url( wp_nonce_url( network_admin_url( 'sites.php?action=confirm&amp;action2=deactivateblog&amp;id=' . $blog['blog_id'] ), 'deactivateblog_' . $blog['blog_id'] ) ) . '">' . __( 'Deactivate' ) . '</a>';
 			}
 
-			if ( $blog['archived'] == '1' ) {
+			if ( '1' == $blog['archived'] ) {
 				$actions['unarchive'] = '<a href="' . esc_url( wp_nonce_url( network_admin_url( 'sites.php?action=confirm&amp;action2=unarchiveblog&amp;id=' . $blog['blog_id'] ), 'unarchiveblog_' . $blog['blog_id'] ) ) . '">' . __( 'Unarchive' ) . '</a>';
 			} else {
 				$actions['archive'] = '<a href="' . esc_url( wp_nonce_url( network_admin_url( 'sites.php?action=confirm&amp;action2=archiveblog&amp;id=' . $blog['blog_id'] ), 'archiveblog_' . $blog['blog_id'] ) ) . '">' . _x( 'Archive', 'verb; site' ) . '</a>';
 			}
 
-			if ( $blog['spam'] == '1' ) {
+			if ( '1' == $blog['spam'] ) {
 				$actions['unspam'] = '<a href="' . esc_url( wp_nonce_url( network_admin_url( 'sites.php?action=confirm&amp;action2=unspamblog&amp;id=' . $blog['blog_id'] ), 'unspamblog_' . $blog['blog_id'] ) ) . '">' . _x( 'Not Spam', 'site' ) . '</a>';
 			} else {
 				$actions['spam'] = '<a href="' . esc_url( wp_nonce_url( network_admin_url( 'sites.php?action=confirm&amp;action2=spamblog&amp;id=' . $blog['blog_id'] ), 'spamblog_' . $blog['blog_id'] ) ) . '">' . _x( 'Spam', 'site' ) . '</a>';
@@ -577,6 +733,7 @@
 		 *                           or subdirectory multisite installation.
 		 */
 		$actions = apply_filters( 'manage_sites_action_links', array_filter( $actions ), $blog['blog_id'], $blogname );
+
 		return $this->row_actions( $actions );
 	}
 }