Comments: Hide zero-count status filters on the Comments list table

src/js/_enqueues/admin/edit-comments.js

@@ -642,6 +642,18 @@ window.setCommentsList = function() {
 			updateCountText( 'span.trash-count', trashDiff );
 		}
 
+		/*
+		 * Status links (e.g. "Trash") are hidden entirely when their count is
+		 * zero, so the count updates above have nothing to show/hide. Replace
+		 * the whole view tabs list with a freshly rendered, authoritative copy
+		 * from the server so a status that just went from zero to non-zero
+		 * (or vice versa) appears or disappears immediately. This must run
+		 * after the count updates above, since it supersedes them.
+		 */
+		if ( response.supplemental && response.supplemental.comment_status_links ) {
+			$( '.subsubsub' ).replaceWith( response.supplemental.comment_status_links );
+		}
+
 		if (
 			( ( 'trash' === settings.data.comment_status ) && !getCount( $( 'span.trash-count' ) ) ) ||
 			( ( 'spam' === settings.data.comment_status ) && !getCount( $( 'span.spam-count' ) ) )

src/wp-admin/includes/ajax-actions.php

@@ -570,6 +570,38 @@ function _wp_ajax_delete_comment_response( $comment_id, $delta = -1 ) {
 	$comment = get_comment( $comment_id );
 	$counts  = wp_count_comments();
 
+	/*
+	 * Re-render the comment status view tabs so that a status link which just
+	 * went from zero to non-zero comments (e.g. "Trash" after trashing the
+	 * first comment) shows up immediately, instead of only after a full page
+	 * reload. Status links are hidden entirely when their count is zero (see
+	 * WP_Comments_List_Table::get_views()), so updating a count in place via
+	 * JS has nothing to update if the link was never rendered.
+	 */
+	$parsed_url = parse_url( $url );
+	$query_vars = array();
+
+	if ( ! empty( $parsed_url['query'] ) ) {
+		parse_str( $parsed_url['query'], $query_vars );
+	}
+
+	$valid_comment_statuses = array( 'all', 'mine', 'moderated', 'approved', 'spam', 'trash' );
+	$current_comment_status = ! empty( $query_vars['comment_status'] ) ? $query_vars['comment_status'] : 'all';
+
+	if ( ! in_array( $current_comment_status, $valid_comment_statuses, true ) ) {
+		$current_comment_status = 'all';
+	}
+
+	$wp_list_table = _get_list_table( 'WP_Comments_List_Table', array( 'screen' => 'edit-comments' ) );
+
+	global $post_id, $comment_status;
+	$post_id        = ! empty( $query_vars['p'] ) ? (int) $query_vars['p'] : 0;
+	$comment_status = $current_comment_status;
+
+	ob_start();
+	$wp_list_table->views();
+	$comment_status_links = ob_get_clean();
+
 	$response = new WP_Ajax_Response(
 		array(
 			'what'         => 'comment',
@@ -589,6 +621,7 @@ function _wp_ajax_delete_comment_response( $comment_id, $delta = -1 ) {
 					_n( '%s Comment in moderation', '%s Comments in moderation', $counts->moderated ),
 					number_format_i18n( $counts->moderated )
 				),
+				'comment_status_links' => $comment_status_links,
 			),
 		)
 	);

src/wp-admin/includes/class-wp-comments-list-table.php

@@ -327,6 +327,21 @@ protected function get_views() {
 				$num_comments->$status = 10;
 			}
 
+			/*
+			 * Don't show "Mine", "Spam", or "Trash" when they have zero comments, to avoid
+			 * cluttering the moderation queue with filters that return no results. "All",
+			 * "Pending", and "Approved" always stay visible: pending is an active task queue
+			 * where "(0)" is reassuring confirmation, and approved is the default working view.
+			 * The currently requested view is never hidden, regardless of its count, so the
+			 * admin always has a visual indicator of what's being filtered (e.g. landing on
+			 * ?comment_status=moderated from a notification after it's already been cleared).
+			 */
+			$always_visible = array( 'all', 'moderated', 'approved' );
+
+			if ( ! in_array( $status, $always_visible, true ) && empty( $num_comments->$status ) && $status !== $comment_status ) {
+				continue;
+			}
+
 			$link = add_query_arg( 'comment_status', $status, $link );
 
 			if ( $post_id ) {

tests/phpunit/tests/admin/wpCommentsListTable.php

@@ -196,22 +196,57 @@ public function test_sortable_columns_with_current_ordering() {
 	}
 
 	/**
-	 * @ticket 42066
-	 *
 	 * @covers WP_Comments_List_Table::get_views
 	 */
-	public function test_get_views_should_return_views_by_default() {
+	public function test_get_views_should_hide_empty_status_links() {
 		$this->table->prepare_items();
 
-		$expected = array(
-			'all'       => '<a href="http://' . WP_TESTS_DOMAIN . '/wp-admin/edit-comments.php?comment_status=all" class="current" aria-current="page">All <span class="count">(<span class="all-count">0</span>)</span></a>',
-			'mine'      => '<a href="http://' . WP_TESTS_DOMAIN . '/wp-admin/edit-comments.php?comment_status=mine&#038;user_id=0">Mine <span class="count">(<span class="mine-count">0</span>)</span></a>',
-			'moderated' => '<a href="http://' . WP_TESTS_DOMAIN . '/wp-admin/edit-comments.php?comment_status=moderated">Pending <span class="count">(<span class="pending-count">0</span>)</span></a>',
-			'approved'  => '<a href="http://' . WP_TESTS_DOMAIN . '/wp-admin/edit-comments.php?comment_status=approved">Approved <span class="count">(<span class="approved-count">0</span>)</span></a>',
-			'spam'      => '<a href="http://' . WP_TESTS_DOMAIN . '/wp-admin/edit-comments.php?comment_status=spam">Spam <span class="count">(<span class="spam-count">0</span>)</span></a>',
-			'trash'     => '<a href="http://' . WP_TESTS_DOMAIN . '/wp-admin/edit-comments.php?comment_status=trash">Trash <span class="count">(<span class="trash-count">0</span>)</span></a>',
+		$views = $this->table->get_views();
+
+		$this->assertArrayHasKey( 'all', $views, 'The "All" view should always be shown.' );
+		$this->assertArrayHasKey( 'moderated', $views, '"Pending" should always be shown, even at zero.' );
+		$this->assertArrayHasKey( 'approved', $views, '"Approved" should always be shown, even at zero.' );
+		$this->assertArrayNotHasKey( 'mine', $views, 'Views with a zero count should be hidden.' );
+		$this->assertArrayNotHasKey( 'spam', $views, 'Views with a zero count should be hidden.' );
+		$this->assertArrayNotHasKey( 'trash', $views, 'Views with a zero count should be hidden.' );
+	}
+
+	/**
+	 * @covers WP_Comments_List_Table::get_views
+	 */
+	public function test_get_views_should_show_status_link_with_nonzero_count() {
+		$post_id = self::factory()->post->create();
+		self::factory()->comment->create(
+			array(
+				'comment_post_ID'  => $post_id,
+				'comment_approved' => '1',
+			)
 		);
-		$this->assertSame( $expected, $this->table->get_views() );
+
+		$this->table->prepare_items();
+
+		$views = $this->table->get_views();
+
+		$this->assertArrayHasKey( 'approved', $views, 'A view with a nonzero count should be shown.' );
+		$this->assertArrayHasKey( 'moderated', $views, '"Pending" should always be shown, even at zero.' );
+		$this->assertArrayNotHasKey( 'spam', $views, 'Views with a zero count should still be hidden.' );
+		$this->assertArrayNotHasKey( 'trash', $views, 'Views with a zero count should still be hidden.' );
+	}
+
+	/**
+	 * @covers WP_Comments_List_Table::get_views
+	 */
+	public function test_get_views_should_not_hide_the_currently_active_status() {
+		$_REQUEST['comment_status'] = 'spam';
+
+		$this->table->prepare_items();
+
+		$views = $this->table->get_views();
+
+		$this->assertArrayHasKey( 'spam', $views, 'The currently active view must never be hidden, even at zero count.' );
+		$this->assertStringContainsString( 'class="current"', $views['spam'], 'The currently active view should be marked current.' );
+
+		unset( $_REQUEST['comment_status'] );
 	}
 
 	/**

tests/phpunit/tests/admin/wpPostCommentsListTable.php

@@ -18,21 +18,18 @@ public function set_up() {
 	}
 
 	/**
-	 * @ticket 42066
-	 *
 	 * @covers WP_Post_Comments_List_Table::get_views
 	 */
-	public function test_get_views_should_return_views_by_default() {
+	public function test_get_views_should_hide_empty_status_links() {
 		$this->table->prepare_items();
 
-		$expected = array(
-			'all'       => '<a href="http://' . WP_TESTS_DOMAIN . '/wp-admin/edit-comments.php?comment_status=all" class="current" aria-current="page">All <span class="count">(<span class="all-count">0</span>)</span></a>',
-			'mine'      => '<a href="http://' . WP_TESTS_DOMAIN . '/wp-admin/edit-comments.php?comment_status=mine&#038;user_id=0">Mine <span class="count">(<span class="mine-count">0</span>)</span></a>',
-			'moderated' => '<a href="http://' . WP_TESTS_DOMAIN . '/wp-admin/edit-comments.php?comment_status=moderated">Pending <span class="count">(<span class="pending-count">0</span>)</span></a>',
-			'approved'  => '<a href="http://' . WP_TESTS_DOMAIN . '/wp-admin/edit-comments.php?comment_status=approved">Approved <span class="count">(<span class="approved-count">0</span>)</span></a>',
-			'spam'      => '<a href="http://' . WP_TESTS_DOMAIN . '/wp-admin/edit-comments.php?comment_status=spam">Spam <span class="count">(<span class="spam-count">0</span>)</span></a>',
-			'trash'     => '<a href="http://' . WP_TESTS_DOMAIN . '/wp-admin/edit-comments.php?comment_status=trash">Trash <span class="count">(<span class="trash-count">0</span>)</span></a>',
-		);
-		$this->assertSame( $expected, $this->table->get_views() );
+		$views = $this->table->get_views();
+
+		$this->assertArrayHasKey( 'all', $views, 'The "All" view should always be shown.' );
+		$this->assertArrayHasKey( 'moderated', $views, '"Pending" should always be shown, even at zero.' );
+		$this->assertArrayHasKey( 'approved', $views, '"Approved" should always be shown, even at zero.' );
+		$this->assertArrayNotHasKey( 'mine', $views, 'Views with a zero count should be hidden.' );
+		$this->assertArrayNotHasKey( 'spam', $views, 'Views with a zero count should be hidden.' );
+		$this->assertArrayNotHasKey( 'trash', $views, 'Views with a zero count should be hidden.' );
 	}
 }

tests/phpunit/tests/ajax/wpAjaxDeleteComment.php

@@ -216,6 +216,47 @@
 		}
 	}
 
+	/**
+	 * Trashing the only trashable comment should make the previously-hidden
+	 * "Trash" status link appear in the same response, rather than only
+	 * after a full page reload.
+	 *
+	 * @covers ::_wp_ajax_delete_comment_response
+	 */
+	public function test_trashing_only_trashed_comment_includes_trash_link_in_response() {
+		$this->_setRole( 'administrator' );
+
+		$comment_id = self::factory()->comment->create(
+			array(
+				'comment_post_ID'  => self::$post_id,
+				'comment_approved' => '1',
+			)
+		);
+
+		$_POST['id']          = $comment_id;
+		$_POST['_ajax_nonce'] = wp_create_nonce( 'delete-comment_' . $comment_id );
+		$_POST['trash']       = '1';
+		$_POST['_total']      = '1';
+		$_POST['_per_page']   = '20';
+		$_POST['_page']       = '1';
+		$_POST['_url']        = admin_url( 'edit-comments.php' );
+
+		try {
+			$this->_handleAjax( 'delete-comment' );
+		} catch ( WPAjaxDieContinueException $e ) {
+			unset( $e );
+		}
+
+		$xml                   = simplexml_load_string( $this->_last_response, 'SimpleXMLElement', LIBXML_NOCDATA );
+		$comment_status_links  = (string) $xml->response[0]->comment[0]->supplemental[0]->comment_status_links[0];
+
+		$this->assertStringContainsString(
+			'comment_status=trash',
+			$comment_status_links,
+			'The "Trash" status link should appear once a comment has actually been trashed.'
+		);
+	}
+
 	/**
 	 * Tests doubling the action (e.g. trash a trashed comment).
 	 *