From 3edf4789a4cd105ec3c9b0a81b09dd2c31dfc190 Mon Sep 17 00:00:00 2001
From: Huzaifa Al Mesbah <huzaifah4m@gmail.com>
Date: Tue, 20 Oct 2026 08:53:08 +0600
Subject: [PATCH] Tests: Add unit test coverage for the plugin activation,
 deactivation and uninstall hook functions.

---
 .../functions/registerActivationHook.php      |  60 ++++++++
 .../functions/registerDeactivationHook.php    |  60 ++++++++
 .../tests/functions/registerUninstallHook.php | 145 ++++++++++++++++++
 3 files changed, 265 insertions(+)
 create mode 100644 tests/phpunit/tests/functions/registerActivationHook.php
 create mode 100644 tests/phpunit/tests/functions/registerDeactivationHook.php
 create mode 100644 tests/phpunit/tests/functions/registerUninstallHook.php

diff --git a/tests/phpunit/tests/functions/registerActivationHook.php b/tests/phpunit/tests/functions/registerActivationHook.php
new file mode 100644
index 0000000000000..077a88a387349
--- /dev/null
+++ b/tests/phpunit/tests/functions/registerActivationHook.php
@@ -0,0 +1,60 @@
+<?php
+
+/**
+ * Tests for register_activation_hook().
+ *
+ * @group functions
+ * @group plugins
+ *
+ * @covers ::register_activation_hook
+ */
+class Tests_Functions_RegisterActivationHook extends WP_UnitTestCase {
+
+	/**
+	 * Tests that the callback is hooked to the activation action of the plugin basename.
+	 *
+	 * @ticket 65819
+	 *
+	 * @dataProvider data_plugin_files
+	 *
+	 * @param string $file     The plugin file.
+	 * @param string $basename The expected plugin basename.
+	 */
+	public function test_should_hook_callback_to_activation_action( $file, $basename ) {
+		register_activation_hook( $file, 'my_plugin_activate' );
+
+		$this->assertSame( 10, has_action( 'activate_' . $basename, 'my_plugin_activate' ) );
+	}
+
+	/**
+	 * Data provider.
+	 *
+	 * @return array[]
+	 */
+	public static function data_plugin_files() {
+		return array(
+			'plugin in a directory' => array( WP_PLUGIN_DIR . '/my-plugin/my-plugin.php', 'my-plugin/my-plugin.php' ),
+			'single-file plugin'    => array( WP_PLUGIN_DIR . '/my-plugin.php', 'my-plugin.php' ),
+			'relative path'         => array( 'my-plugin/my-plugin.php', 'my-plugin/my-plugin.php' ),
+			'must-use plugin'       => array( WPMU_PLUGIN_DIR . '/my-mu-plugin.php', 'my-mu-plugin.php' ),
+			'backslash separators'  => array( str_replace( '/', '\\', WP_PLUGIN_DIR . '/my-plugin/my-plugin.php' ), 'my-plugin/my-plugin.php' ),
+		);
+	}
+
+	/**
+	 * Tests that the callback runs when the plugin is activated.
+	 *
+	 * @ticket 65819
+	 */
+	public function test_should_run_callback_on_activation() {
+		$action = new MockAction();
+
+		register_activation_hook( WP_PLUGIN_DIR . '/my-plugin/my-plugin.php', array( $action, 'action' ) );
+
+		$plugin = 'my-plugin/my-plugin.php';
+		do_action( "activate_{$plugin}", true );
+
+		$this->assertSame( 1, $action->get_call_count(), 'The callback should run once.' );
+		$this->assertSame( array( array( true ) ), $action->get_args(), 'The callback should receive the network-wide flag.' );
+	}
+}
diff --git a/tests/phpunit/tests/functions/registerDeactivationHook.php b/tests/phpunit/tests/functions/registerDeactivationHook.php
new file mode 100644
index 0000000000000..998ad34e4d33a
--- /dev/null
+++ b/tests/phpunit/tests/functions/registerDeactivationHook.php
@@ -0,0 +1,60 @@
+<?php
+
+/**
+ * Tests for register_deactivation_hook().
+ *
+ * @group functions
+ * @group plugins
+ *
+ * @covers ::register_deactivation_hook
+ */
+class Tests_Functions_RegisterDeactivationHook extends WP_UnitTestCase {
+
+	/**
+	 * Tests that the callback is hooked to the deactivation action of the plugin basename.
+	 *
+	 * @ticket 65819
+	 *
+	 * @dataProvider data_plugin_files
+	 *
+	 * @param string $file     The plugin file.
+	 * @param string $basename The expected plugin basename.
+	 */
+	public function test_should_hook_callback_to_deactivation_action( $file, $basename ) {
+		register_deactivation_hook( $file, 'my_plugin_deactivate' );
+
+		$this->assertSame( 10, has_action( 'deactivate_' . $basename, 'my_plugin_deactivate' ) );
+	}
+
+	/**
+	 * Data provider.
+	 *
+	 * @return array[]
+	 */
+	public static function data_plugin_files() {
+		return array(
+			'plugin in a directory' => array( WP_PLUGIN_DIR . '/my-plugin/my-plugin.php', 'my-plugin/my-plugin.php' ),
+			'single-file plugin'    => array( WP_PLUGIN_DIR . '/my-plugin.php', 'my-plugin.php' ),
+			'relative path'         => array( 'my-plugin/my-plugin.php', 'my-plugin/my-plugin.php' ),
+			'must-use plugin'       => array( WPMU_PLUGIN_DIR . '/my-mu-plugin.php', 'my-mu-plugin.php' ),
+			'backslash separators'  => array( str_replace( '/', '\\', WP_PLUGIN_DIR . '/my-plugin/my-plugin.php' ), 'my-plugin/my-plugin.php' ),
+		);
+	}
+
+	/**
+	 * Tests that the callback runs when the plugin is deactivated.
+	 *
+	 * @ticket 65819
+	 */
+	public function test_should_run_callback_on_deactivation() {
+		$action = new MockAction();
+
+		register_deactivation_hook( WP_PLUGIN_DIR . '/my-plugin/my-plugin.php', array( $action, 'action' ) );
+
+		$plugin = 'my-plugin/my-plugin.php';
+		do_action( "deactivate_{$plugin}", true );
+
+		$this->assertSame( 1, $action->get_call_count(), 'The callback should run once.' );
+		$this->assertSame( array( array( true ) ), $action->get_args(), 'The callback should receive the network-wide flag.' );
+	}
+}
diff --git a/tests/phpunit/tests/functions/registerUninstallHook.php b/tests/phpunit/tests/functions/registerUninstallHook.php
new file mode 100644
index 0000000000000..338f6a069ce93
--- /dev/null
+++ b/tests/phpunit/tests/functions/registerUninstallHook.php
@@ -0,0 +1,145 @@
+<?php
+
+/**
+ * Tests for register_uninstall_hook().
+ *
+ * @group functions
+ * @group plugins
+ *
+ * @covers ::register_uninstall_hook
+ */
+class Tests_Functions_RegisterUninstallHook extends WP_UnitTestCase {
+
+	/**
+	 * Number of times the uninstall_plugins option was saved.
+	 *
+	 * @var int
+	 */
+	private $option_updates = 0;
+
+	/**
+	 * Starts each test with no uninstall callbacks and counts option updates.
+	 */
+	public function set_up() {
+		parent::set_up();
+
+		update_option( 'uninstall_plugins', array() );
+
+		add_filter( 'pre_update_option_uninstall_plugins', array( $this, 'count_option_update' ) );
+	}
+
+	/**
+	 * Tests that a function name is stored under the plugin basename.
+	 *
+	 * @ticket 65819
+	 *
+	 * @dataProvider data_callbacks
+	 *
+	 * @param callable $callback The uninstall callback.
+	 */
+	public function test_should_store_callback_under_plugin_basename( $callback ) {
+		register_uninstall_hook( WP_PLUGIN_DIR . '/my-plugin/my-plugin.php', $callback );
+
+		$this->assertSame( array( 'my-plugin/my-plugin.php' => $callback ), get_option( 'uninstall_plugins' ) );
+	}
+
+	/**
+	 * Data provider.
+	 *
+	 * @return array[]
+	 */
+	public static function data_callbacks() {
+		return array(
+			'function name'           => array( 'my_plugin_uninstall' ),
+			'static method as string' => array( 'My_Plugin::uninstall' ),
+			'static method as array'  => array( array( 'My_Plugin', 'uninstall' ) ),
+		);
+	}
+
+	/**
+	 * Tests that an object method is rejected.
+	 *
+	 * @ticket 65819
+	 *
+	 * @expectedIncorrectUsage register_uninstall_hook
+	 */
+	public function test_should_reject_object_method() {
+		register_uninstall_hook( WP_PLUGIN_DIR . '/my-plugin/my-plugin.php', array( new stdClass(), 'uninstall' ) );
+
+		$this->assertSame( array(), get_option( 'uninstall_plugins' ), 'No callback should be stored.' );
+		$this->assertSame( 0, $this->option_updates, 'The option should not be updated.' );
+	}
+
+	/**
+	 * Tests that callbacks of other plugins are kept.
+	 *
+	 * @ticket 65819
+	 */
+	public function test_should_keep_callbacks_of_other_plugins() {
+		update_option( 'uninstall_plugins', array( 'other-plugin/other-plugin.php' => 'other_plugin_uninstall' ) );
+
+		register_uninstall_hook( WP_PLUGIN_DIR . '/my-plugin/my-plugin.php', 'my_plugin_uninstall' );
+
+		$this->assertSame(
+			array(
+				'other-plugin/other-plugin.php' => 'other_plugin_uninstall',
+				'my-plugin/my-plugin.php'       => 'my_plugin_uninstall',
+			),
+			get_option( 'uninstall_plugins' )
+		);
+	}
+
+	/**
+	 * Tests that a different callback for the same plugin replaces the stored one.
+	 *
+	 * @ticket 65819
+	 */
+	public function test_should_replace_changed_callback() {
+		update_option( 'uninstall_plugins', array( 'my-plugin/my-plugin.php' => 'old_uninstall' ) );
+		$this->option_updates = 0;
+
+		register_uninstall_hook( WP_PLUGIN_DIR . '/my-plugin/my-plugin.php', 'new_uninstall' );
+
+		$this->assertSame( array( 'my-plugin/my-plugin.php' => 'new_uninstall' ), get_option( 'uninstall_plugins' ), 'The callback should be replaced.' );
+		$this->assertSame( 1, $this->option_updates, 'The option should be updated once.' );
+	}
+
+	/**
+	 * Tests that the option is not saved again when the callback is unchanged.
+	 *
+	 * @ticket 65819
+	 */
+	public function test_should_not_update_option_when_callback_is_unchanged() {
+		update_option( 'uninstall_plugins', array( 'my-plugin/my-plugin.php' => 'my_plugin_uninstall' ) );
+		$this->option_updates = 0;
+
+		register_uninstall_hook( WP_PLUGIN_DIR . '/my-plugin/my-plugin.php', 'my_plugin_uninstall' );
+
+		$this->assertSame( 0, $this->option_updates );
+	}
+
+	/**
+	 * Tests that a stored callback of another type is replaced.
+	 *
+	 * @ticket 65819
+	 */
+	public function test_should_replace_callback_of_another_type() {
+		update_option( 'uninstall_plugins', array( 'my-plugin/my-plugin.php' => array( 'My_Plugin', 'uninstall' ) ) );
+
+		register_uninstall_hook( WP_PLUGIN_DIR . '/my-plugin/my-plugin.php', 'My_Plugin::uninstall' );
+
+		$this->assertSame( array( 'my-plugin/my-plugin.php' => 'My_Plugin::uninstall' ), get_option( 'uninstall_plugins' ) );
+	}
+
+	/**
+	 * Counts updates of the uninstall_plugins option.
+	 *
+	 * @param mixed $value The new option value.
+	 * @return mixed The unchanged value.
+	 */
+	public function count_option_update( $value ) {
+		++$this->option_updates;
+
+		return $value;
+	}
+}