Set count-based sortable columns to default to initial DESC ordering

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

@@ -154,7 +154,7 @@ protected function get_sortable_columns() {
 			'name'    => array( 'name', false, _x( 'Name', 'link name' ), __( 'Table ordered by Name.' ), 'asc' ),
 			'url'     => array( 'url', false, __( 'URL' ), __( 'Table ordered by URL.' ) ),
 			'visible' => array( 'visible', false, __( 'Visible' ), __( 'Table ordered by Visibility.' ) ),
-			'rating'  => array( 'rating', false, __( 'Rating' ), __( 'Table ordered by Rating.' ) ),
+			'rating'  => array( 'rating', true, __( 'Rating' ), __( 'Table ordered by Rating.' ) ),
 		);
 	}
 

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

@@ -431,7 +431,7 @@ protected function get_sortable_columns() {
 			'title'    => array( 'title', false, _x( 'File', 'column name' ), __( 'Table ordered by File Name.' ) ),
 			'author'   => array( 'author', false, __( 'Author' ), __( 'Table ordered by Author.' ) ),
 			'parent'   => array( 'parent', false, _x( 'Uploaded to', 'column name' ), __( 'Table ordered by Uploaded To.' ) ),
-			'comments' => array( 'comment_count', __( 'Comments' ), false, __( 'Table ordered by Comments.' ) ),
+			'comments' => array( 'comment_count', true, __( 'Comments' ), __( 'Table ordered by Comments.' ) ),
 			'date'     => array( 'date', true, __( 'Date' ), __( 'Table ordered by Date.' ), 'desc' ),
 		);
 	}

src/wp-admin/includes/class-wp-ms-users-list-table.php

@@ -215,7 +215,7 @@ protected function get_sortable_columns() {
 			'username'   => array( 'login', false, __( 'Username' ), __( 'Table ordered by Username.' ), 'asc' ),
 			'name'       => array( 'name', false, __( 'Name' ), __( 'Table ordered by Name.' ) ),
 			'email'      => array( 'email', false, __( 'E-mail' ), __( 'Table ordered by E-mail.' ) ),
-			'registered' => array( 'id', false, _x( 'Registered', 'user' ), __( 'Table ordered by User Registered Date.' ) ),
+			'registered' => array( 'id', true, _x( 'Registered', 'user' ), __( 'Table ordered by User Registered Date.' ) ),
 		);
 	}
 

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

@@ -772,14 +772,14 @@ protected function get_sortable_columns() {
 			$sortables = array(
 				'title'    => array( 'title', false, __( 'Title' ), $title_orderby_text, 'asc' ),
 				'parent'   => array( 'parent', false ),
-				'comments' => array( 'comment_count', false, __( 'Comments' ), __( 'Table ordered by Comments.' ) ),
+				'comments' => array( 'comment_count', true, __( 'Comments' ), __( 'Table ordered by Comments.' ) ),
 				'date'     => array( 'date', true, __( 'Date' ), __( 'Table ordered by Date.' ) ),
 			);
 		} else {
 			$sortables = array(
 				'title'    => array( 'title', false, __( 'Title' ), __( 'Table ordered by Title.' ) ),
 				'parent'   => array( 'parent', false ),
-				'comments' => array( 'comment_count', false, __( 'Comments' ), __( 'Table ordered by Comments.' ) ),
+				'comments' => array( 'comment_count', true, __( 'Comments' ), __( 'Table ordered by Comments.' ) ),
 				'date'     => array( 'date', true, __( 'Date' ), __( 'Table ordered by Date.' ), 'desc' ),
 			);
 		}

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

@@ -219,8 +219,8 @@ protected function get_sortable_columns() {
 			'name'        => array( 'name', false, _x( 'Name', 'term name' ), $name_orderby_text, 'asc' ),
 			'description' => array( 'description', false, __( 'Description' ), __( 'Table ordered by Description.' ) ),
 			'slug'        => array( 'slug', false, __( 'Slug' ), __( 'Table ordered by Slug.' ) ),
-			'posts'       => array( 'count', false, _x( 'Count', 'Number/count of items' ), __( 'Table ordered by Posts Count.' ) ),
-			'links'       => array( 'count', false, __( 'Links' ), __( 'Table ordered by Links.' ) ),
+			'posts'       => array( 'count', true, _x( 'Count', 'Number/count of items' ), __( 'Table ordered by Posts Count.' ) ),
+			'links'       => array( 'count', true, __( 'Links' ), __( 'Table ordered by Links.' ) ),
 		);
 	}
 

tests/phpunit/tests/admin/wpLinksListTable.php

@@ -0,0 +1,26 @@
+<?php
+
+/**
+ * @group admin
+ */
+class Tests_Admin_wpLinksListTable extends WP_UnitTestCase {
+	/**
+	 * @var WP_Links_List_Table
+	 */
+	private $table;
+
+	public function set_up() {
+		parent::set_up();
+		$this->table = _get_list_table( 'WP_Links_List_Table', array( 'screen' => 'link-manager' ) );
+	}
+
+	/**
+	 * @covers WP_Links_List_Table::print_column_headers
+	 */
+	public function test_sortable_columns_set_rating_descending_by_default() {
+		$output = get_echo( array( $this->table, 'print_column_headers' ) );
+
+		$this->assertStringContainsString( '?orderby=rating&#038;order=desc', $output, 'Mismatch of the default link ordering for rating column. Should be desc.' );
+		$this->assertStringContainsString( 'column-rating sortable asc', $output, 'Mismatch of CSS classes for the rating column.' );
+	}
+}

tests/phpunit/tests/admin/wpMediaListTable.php

@@ -479,6 +479,27 @@ public function test_get_row_actions_should_not_include_download_without_an_atta
 		$this->assertArrayNotHasKey( 'download', $actions, '"download" was included in the actions.' );
 	}
 
+	/**
+	 * @covers WP_Media_List_Table::print_column_headers
+	 */
+	public function test_sortable_columns_set_comments_descending_by_default() {
+		$attachment_pages_enabled = get_option( 'wp_attachment_pages_enabled' );
+
+		add_post_type_support( 'attachment', 'comments' );
+		update_option( 'wp_attachment_pages_enabled', 1 );
+
+		$output = get_echo( array( self::$list_table, 'print_column_headers' ) );
+
+		if ( false === $attachment_pages_enabled ) {
+			delete_option( 'wp_attachment_pages_enabled' );
+		} else {
+			update_option( 'wp_attachment_pages_enabled', $attachment_pages_enabled );
+		}
+
+		$this->assertStringContainsString( '?orderby=comment_count&order=desc', $output, 'Mismatch of the default link ordering for comments column. Should be desc.' );
+		$this->assertMatchesRegularExpression( '/column-comments[^"\\n]*sortable asc/', $output, 'Mismatch of CSS classes for the comments column.' );
+	}
+
 	/**
 	 * Sets the `$is_trash` property.
 	 *

tests/phpunit/tests/admin/wpPostsListTable.php

@@ -330,4 +330,14 @@ public function test_get_views_should_return_views_by_default() {
 
 		$this->assertSame( $expected, $actual );
 	}
+
+	/**
+	 * @covers WP_Posts_List_Table::print_column_headers
+	 */
+	public function test_sortable_columns_set_comments_descending_by_default() {
+		$output = get_echo( array( $this->table, 'print_column_headers' ) );
+
+		$this->assertStringContainsString( '?orderby=comment_count&order=desc', $output, 'Mismatch of the default link ordering for comments column. Should be desc.' );
+		$this->assertMatchesRegularExpression( '/column-comments[^"\\n]*sortable asc/', $output, 'Mismatch of CSS classes for the comments column.' );
+	}
 }

tests/phpunit/tests/admin/wpTermsListTable.php

@@ -87,4 +87,14 @@ public function test_handle_row_actions_as_admin() {
 		$this->assertStringContainsString( 'Delete', $actions, 'Delete action should be displayed to the admin.' );
 		$this->assertStringContainsString( admin_url( 'term.php' ), $actions, 'Edit term link should be displayed to the admin.' );
 	}
+
+	/**
+	 * @covers WP_Terms_List_Table::print_column_headers
+	 */
+	public function test_sortable_columns_set_count_columns_descending_by_default() {
+		$category_output = get_echo( array( $this->terms_list_table, 'print_column_headers' ) );
+
+		$this->assertStringContainsString( '?orderby=count&order=desc', $category_output, 'Mismatch of the default link ordering for posts count column. Should be desc.' );
+		$this->assertStringContainsString( 'column-posts sortable asc', $category_output, 'Mismatch of CSS classes for the posts count column.' );
+	}
 }

tests/phpunit/tests/multisite/wpMsUsersListTable.php

@@ -104,4 +104,14 @@ public function test_get_views_should_return_views_by_default() {
 
 		$this->assertSame( $expected, $this->table->get_views() );
 	}
+
+	/**
+	 * @covers WP_MS_Users_List_Table::print_column_headers
+	 */
+	public function test_sortable_columns_set_registered_descending_by_default() {
+		$output = get_echo( array( $this->table, 'print_column_headers' ) );
+
+		$this->assertStringContainsString( '?orderby=id&order=desc', $output, 'Mismatch of the default link ordering for registered column. Should be desc.' );
+		$this->assertStringContainsString( 'column-registered sortable asc', $output, 'Mismatch of CSS classes for the registered column.' );
+	}
 }