Stats: add self-hosted admin bar link

projects/plugins/jetpack/changelog/add-self-hosted-stats-admin-bar-link

@@ -0,0 +1,4 @@
+Significance: patch
+Type: enhancement
+
+Stats: Add a link to the site-name admin bar menu.

projects/plugins/jetpack/modules/stats.php

@@ -65,6 +65,7 @@ function stats_load() {
 	Admin_Post_List_Column::register();
 
 	add_action( 'jetpack_admin_menu', 'stats_admin_menu' );
+	add_action( 'wp_before_admin_bar_render', 'stats_add_link_to_admin_bar_site_menu' );
 
 	add_filter( 'pre_option_db_version', 'stats_ignore_db_version' );
 
@@ -824,6 +825,34 @@ function stats_admin_bar_menu( &$wp_admin_bar ) {
 	$wp_admin_bar->add_menu( $menu );
 }
 
+/**
+ * Adds a Stats link to the site-name admin bar submenu, alongside Dashboard.
+ *
+ * @access public
+ * @return void
+ */
+function stats_add_link_to_admin_bar_site_menu() {
+	global $wp_admin_bar;
+
+	if (
+		! is_object( $wp_admin_bar ) ||
+		! $wp_admin_bar->get_node( 'dashboard' ) ||
+		! current_user_can( 'view_stats' ) ||
+		( new Host() )->is_wpcom_platform()
+	) {
+		return;
+	}
+
+	$wp_admin_bar->add_node(
+		array(
+			'parent' => 'site-name',
+			'id'     => 'jetpack-stats',
+			'title'  => __( 'Stats', 'jetpack' ),
+			'href'   => admin_url( 'admin.php?page=stats' ),
+		)
+	);
+}
+
 /**
  * Stats Get Blog.
  *

projects/plugins/jetpack/phpunit.11.xml.dist

@@ -78,6 +78,9 @@
 		<testsuite name="sitemaps">
 			<directory suffix="Test.php">tests/php/modules/sitemaps</directory>
 		</testsuite>
+		<testsuite name="stats">
+			<directory suffix="Test.php">tests/php/modules/stats</directory>
+		</testsuite>
 		<testsuite name="subscriptions">
 			<directory suffix="Test.php">tests/php/modules/subscriptions</directory>
 		</testsuite>

projects/plugins/jetpack/phpunit.9.xml.dist

@@ -69,6 +69,9 @@
 		<testsuite name="sitemaps">
 			<directory suffix="Test.php">tests/php/modules/sitemaps</directory>
 		</testsuite>
+		<testsuite name="stats">
+			<directory suffix="Test.php">tests/php/modules/stats</directory>
+		</testsuite>
 		<testsuite name="subscriptions">
 			<directory suffix="Test.php">tests/php/modules/subscriptions</directory>
 		</testsuite>

projects/plugins/jetpack/tests/php/modules/stats/Stats_Admin_Bar_Test.php

@@ -0,0 +1,177 @@
+<?php
+/**
+ * Tests for Jetpack Stats admin bar links.
+ *
+ * @package automattic/jetpack
+ */
+
+use Automattic\Jetpack\Constants;
+use Automattic\Jetpack\Status\Cache as Status_Cache;
+
+require_once JETPACK__PLUGIN_DIR . 'modules/stats.php';
+require_once ABSPATH . WPINC . '/class-wp-admin-bar.php';
+
+/**
+ * Test class for Jetpack Stats admin bar links.
+ */
+class Stats_Admin_Bar_Test extends WP_UnitTestCase {
+	use \Automattic\Jetpack\PHPUnit\WP_UnitTestCase_Fix;
+
+	/**
+	 * Set up the test environment.
+	 */
+	public function set_up() {
+		parent::set_up();
+
+		$user_id = self::factory()->user->create(
+			array(
+				'role' => 'administrator',
+			)
+		);
+		wp_set_current_user( $user_id );
+
+		add_action( 'wp_before_admin_bar_render', 'stats_add_link_to_admin_bar_site_menu' );
+	}
+
+	/**
+	 * Tear down the test environment.
+	 */
+	public function tear_down() {
+		self::reset_admin_bar_global();
+		remove_action( 'wp_before_admin_bar_render', 'stats_add_link_to_admin_bar_site_menu' );
+		remove_filter( 'user_has_cap', array( $this, 'grant_view_stats' ) );
+		remove_role( 'jetpack_no_stats' );
+		Constants::clear_constants();
+		Status_Cache::clear();
+		wp_set_current_user( 0 );
+
+		parent::tear_down();
+	}
+
+	/**
+	 * Forces current_user_can( 'view_stats' ) to true for the test.
+	 *
+	 * @param array $allcaps All capabilities of the user.
+	 * @return array
+	 */
+	public function grant_view_stats( $allcaps ) {
+		$allcaps['view_stats'] = true;
+		return $allcaps;
+	}
+
+	/**
+	 * Tests that the Stats link is added when the user can view Stats.
+	 */
+	public function test_stats_link_shown_when_user_can_view_stats() {
+		add_filter( 'user_has_cap', array( $this, 'grant_view_stats' ) );
+		$admin_bar = self::make_test_admin_bar_with_dashboard();
+
+		do_action( 'wp_before_admin_bar_render' );
+
+		$stats_node = $admin_bar->get_node( 'jetpack-stats' );
+
+		$this->assertNotNull( $stats_node );
+		$this->assertSame( 'site-name', $stats_node->parent );
+		$this->assertSame( 'Stats', $stats_node->title );
+		$this->assertSame( admin_url( 'admin.php?page=stats' ), $stats_node->href );
+	}
+
+	/**
+	 * Tests that the Stats link is hidden when the user cannot view Stats.
+	 */
+	public function test_stats_link_hidden_when_user_cannot_view_stats() {
+		add_role( 'jetpack_no_stats', 'No Stats', array( 'read' => true ) );
+		$user_id = self::factory()->user->create(
+			array(
+				'role' => 'jetpack_no_stats',
+			)
+		);
+		wp_set_current_user( $user_id );
+
+		$admin_bar = self::make_test_admin_bar_with_dashboard();
+
+		do_action( 'wp_before_admin_bar_render' );
+
+		$stats_node = $admin_bar->get_node( 'jetpack-stats' );
+
+		$this->assertFalse( current_user_can( 'view_stats' ) );
+		$this->assertNull( $stats_node );
+	}
+
+	/**
+	 * Tests that the Stats link is hidden when core's Dashboard node is absent.
+	 */
+	public function test_stats_link_hidden_when_dashboard_node_absent() {
+		add_filter( 'user_has_cap', array( $this, 'grant_view_stats' ) );
+		$admin_bar = self::make_test_admin_bar();
+
+		do_action( 'wp_before_admin_bar_render' );
+
+		$stats_node = $admin_bar->get_node( 'jetpack-stats' );
+
+		$this->assertNull( $stats_node );
+	}
+
+	/**
+	 * Tests that the Stats link is hidden on WordPress.com platform sites.
+	 */
+	public function test_stats_link_hidden_on_wpcom_platform() {
+		add_filter( 'user_has_cap', array( $this, 'grant_view_stats' ) );
+		Constants::set_constant( 'IS_WPCOM', true );
+		$admin_bar = self::make_test_admin_bar_with_dashboard();
+
+		do_action( 'wp_before_admin_bar_render' );
+
+		$stats_node = $admin_bar->get_node( 'jetpack-stats' );
+
+		$this->assertNull( $stats_node );
+	}
+
+	/**
+	 * Builds a test admin bar with the core site-name node.
+	 *
+	 * @return WP_Admin_Bar
+	 */
+	private static function make_test_admin_bar() {
+		global $wp_admin_bar;
+
+		$wp_admin_bar = new WP_Admin_Bar();
+		$wp_admin_bar->add_node(
+			array(
+				'id'    => 'site-name',
+				'title' => 'Test Site',
+				'href'  => admin_url(),
+			)
+		);
+
+		return $wp_admin_bar;
+	}
+
+	/**
+	 * Builds a test admin bar with core's site-name and dashboard nodes.
+	 *
+	 * @return WP_Admin_Bar
+	 */
+	private static function make_test_admin_bar_with_dashboard() {
+		$admin_bar = self::make_test_admin_bar();
+		$admin_bar->add_node(
+			array(
+				'parent' => 'site-name',
+				'id'     => 'dashboard',
+				'title'  => 'Dashboard',
+				'href'   => admin_url(),
+			)
+		);
+
+		return $admin_bar;
+	}
+
+	/**
+	 * Resets the global admin bar object.
+	 */
+	private static function reset_admin_bar_global() {
+		global $wp_admin_bar;
+
+		$wp_admin_bar = null;
+	}
+}