From 43463bf2880446c6006180302780ea2bf4c7b87d Mon Sep 17 00:00:00 2001
From: Aayushkalikote <aayushkalikote.codewing@gmail.com>
Date: Tue, 20 Oct 2026 14:45:07 +0545
Subject: [PATCH] Plugins: Avoid undefined `activateUrl` key for active plugins
 on multisite.

On multisite, `WP_Plugin_Dependencies::check_plugin_dependencies_during_ajax()` appended `networkwide=1` to `$status['activateUrl']` for every user who can manage network plugins, even when the URL was never set because the plugin is already active. This raised an "Undefined array key" warning and returned a broken `activateUrl` of `?networkwide=1`.

The network-wide argument is now only added when an activation URL exists, matching the single site behavior.

Follow-up to r57545.

Fixes #66346.
---
 .../class-wp-plugin-dependencies.php          |  2 +-
 .../ajax/wpAjaxCheckPluginDependencies.php    | 80 +++++++++++++++++++
 2 files changed, 81 insertions(+), 1 deletion(-)
 create mode 100644 tests/phpunit/tests/ajax/wpAjaxCheckPluginDependencies.php

diff --git a/src/wp-includes/class-wp-plugin-dependencies.php b/src/wp-includes/class-wp-plugin-dependencies.php
index c96b98d08b550..fab7406622a11 100644
--- a/src/wp-includes/class-wp-plugin-dependencies.php
+++ b/src/wp-includes/class-wp-plugin-dependencies.php
@@ -477,7 +477,7 @@ public static function check_plugin_dependencies_during_ajax() {
 			);
 		}
 
-		if ( is_multisite() && current_user_can( 'manage_network_plugins' ) ) {
+		if ( isset( $status['activateUrl'] ) && is_multisite() && current_user_can( 'manage_network_plugins' ) ) {
 			$status['activateUrl'] = add_query_arg( array( 'networkwide' => 1 ), $status['activateUrl'] );
 		}
 
diff --git a/tests/phpunit/tests/ajax/wpAjaxCheckPluginDependencies.php b/tests/phpunit/tests/ajax/wpAjaxCheckPluginDependencies.php
new file mode 100644
index 0000000000000..2b3bcbcecefed
--- /dev/null
+++ b/tests/phpunit/tests/ajax/wpAjaxCheckPluginDependencies.php
@@ -0,0 +1,80 @@
+<?php
+
+/**
+ * Admin Ajax functions to be tested.
+ */
+require_once ABSPATH . 'wp-admin/includes/ajax-actions.php';
+
+/**
+ * Testing Ajax handler for checking plugin dependencies.
+ *
+ * @package WordPress
+ * @subpackage UnitTests
+ * @since 7.2.0
+ *
+ * @group ajax
+ * @group ms-required
+ *
+ * @covers WP_Plugin_Dependencies::check_plugin_dependencies_during_ajax
+ */
+class Tests_Ajax_wpAjaxCheckPluginDependencies extends WP_Ajax_UnitTestCase {
+
+	/**
+	 * A user with super admin privileges.
+	 */
+	protected static int $super_admin_id;
+
+	public static function wpSetUpBeforeClass( WP_UnitTest_Factory $factory ) {
+		self::$super_admin_id = $factory->user->create( array( 'role' => 'administrator' ) );
+		grant_super_admin( self::$super_admin_id );
+	}
+
+	public function set_up() {
+		parent::set_up();
+		add_action( 'wp_ajax_check_plugin_dependencies', array( 'WP_Plugin_Dependencies', 'check_plugin_dependencies_during_ajax' ) );
+		wp_set_current_user( self::$super_admin_id );
+	}
+
+	/**
+	 * Runs the Ajax handler for the Hello Dolly plugin and returns the decoded response.
+	 *
+	 * @return array The decoded response.
+	 */
+	protected function check_hello_dolly_dependencies(): array {
+		$_POST['_ajax_nonce'] = wp_create_nonce( 'updates' );
+		$_POST['slug']        = 'hello-dolly';
+
+		try {
+			$this->_handleAjax( 'check_plugin_dependencies' );
+		} catch ( WPAjaxDieContinueException $e ) {
+			unset( $e );
+		}
+
+		return json_decode( $this->_last_response, true );
+	}
+
+	/**
+	 * @ticket 66346
+	 */
+	public function test_network_active_plugin_should_not_have_activate_url() {
+		update_site_option( 'active_sitewide_plugins', array( 'hello.php' => time() ) );
+
+		$response = $this->check_hello_dolly_dependencies();
+
+		$this->assertTrue( $response['success'], 'The request should succeed.' );
+		$this->assertArrayNotHasKey( 'activateUrl', $response['data'], 'An active plugin should not have an activation URL.' );
+	}
+
+	/**
+	 * @ticket 66346
+	 */
+	public function test_inactive_plugin_should_have_network_activate_url() {
+		update_site_option( 'active_sitewide_plugins', array() );
+
+		$response = $this->check_hello_dolly_dependencies();
+
+		$this->assertTrue( $response['success'], 'The request should succeed.' );
+		$this->assertArrayHasKey( 'activateUrl', $response['data'], 'An inactive plugin should have an activation URL.' );
+		$this->assertStringContainsString( 'networkwide=1', $response['data']['activateUrl'], 'The activation URL should activate the plugin network-wide.' );
+	}
+}