Fix template validation failing when addon product is selected

inc/class-ajax.php

@@ -153,6 +153,9 @@ public function search_models(): void {
 
 		$results = [];
 
+		// Merge the caller's query params (search term, etc.) with locally-built params.
+		$query = array_merge($args['query'], $query ?? []);
+
 		if ('user' === $args['model']) {
 			$results = $this->search_wordpress_users($query);
 		} elseif ('page' === $args['model']) {

inc/objects/class-limitations.php

@@ -317,6 +317,13 @@ protected function merge_recursive(array &$array1, array &$array2, $should_sum =
 					 *  We use values 0 or '' as unlimited in our limits
 					 */
 					continue;
+				} elseif ($should_sum && is_null($value) && ! is_null($original_value)) {
+					/*
+					 * Null values should not overwrite existing values in additive mode.
+					 * A null limit means "no restriction configured" and should not
+					 * remove restrictions from previously merged limitations.
+					 */
+					continue;
 				} elseif (isset($array1[ $key ]) && is_numeric($array1[ $key ]) && is_numeric($value) && $should_sum && ! $is_unlimited) {
 					$array1[ $key ] = ((int) $array1[ $key ]) + $value;
 				} elseif ('visibility' === $key && isset($array1[ $key ]) && $should_sum) {
@@ -354,8 +361,6 @@ protected function merge_recursive(array &$array1, array &$array2, $should_sum =
 
 					// Avoid change true values
 					$array1[ $key ] = true !== $original_value || ! $should_sum ? $value : true;
-
-					$array1[ $key ] = true !== $original_value || ! $should_sum ? $value : true;
 				}
 			}
 		}
@@ -463,13 +468,13 @@ public static function remove_limitations($slug, $id): void {
 	 */
 	public static function get_empty() {
 
-		$limitations = new self();
+		$modules_data = [];
 
-		foreach (array_keys(self::repository()) as $module_name) {
-			$limitations->{$module_name};
+		foreach (self::repository() as $module_name => $class_name) {
+			$modules_data[ $module_name ] = $class_name::default_state();
 		}
 
-		return $limitations;
+		return new self($modules_data);
 	}
 
 	/**

patches/mpdf-mpdf-psr-log-aware-trait-void-return.patch

@@ -0,0 +1,11 @@
+--- a/src/PsrLogAwareTrait.php
++++ b/src/PsrLogAwareTrait.php
+@@ -12,7 +12,7 @@
+ 	 */
+ 	protected $logger;
+
+-	public function setLogger(LoggerInterface $logger)
++	public function setLogger(LoggerInterface $logger): void
+ 	{
+ 		$this->logger = $logger;
+ 	}

tests/WP_Ultimo/Objects/Limitations_Test.php

@@ -1,11 +1,11 @@
 <?php
 
 namespace WP_Ultimo\Objects;
 
 use WP_UnitTestCase;
 use WP_Ultimo\Objects\Limitations;
 
 class Limitations_Test extends WP_UnitTestCase {
 
 	/**
 	 * Clear limitations cache before each test.
@@ -71,7 +71,7 @@
 		];
 	}
 
 	/**
 	 * Test constructor with various module data.
 	 *
 	 * @dataProvider constructorDataProvider
@@ -121,7 +121,7 @@
 		];
 	}
 
 	/**
 	 * Test magic getter method.
 	 *
 	 * @dataProvider magicGetterDataProvider
@@ -196,7 +196,7 @@
 		];
 	}
 
 	/**
 	 * Test build_modules method.
 	 *
 	 * @dataProvider buildModulesDataProvider
@@ -257,7 +257,7 @@
 		];
 	}
 
 	/**
 	 * Test static build method.
 	 *
 	 * @dataProvider buildMethodDataProvider
@@ -783,4 +783,131 @@
 
 		$this->assertEquals('force_active', $array1['behavior']);
 	}
+
+	/**
+	 * Test that null limit from addon product does not overwrite plan template list during additive merge.
+	 *
+	 * Regression test: when a plan with configured site templates was merged with an addon product
+	 * that had site_templates.limit = null, the null would overwrite the plan's template list,
+	 * causing "The selected template is not available for this product" validation error.
+	 */
+	public function test_merge_null_limit_does_not_overwrite_template_list(): void {
+
+		$plan_limitations = new Limitations([
+			'site_templates' => [
+				'enabled' => true,
+				'mode'    => 'default',
+				'limit'   => [
+					'2' => ['behavior' => 'available'],
+					'3' => ['behavior' => 'pre_selected'],
+				],
+			],
+		]);
+
+		$addon_limitations = new Limitations([
+			'site_templates' => [
+				'enabled' => true,
+				'mode'    => 'default',
+				'limit'   => null,
+			],
+		]);
+
+		$merged = $plan_limitations->merge($addon_limitations);
+
+		$available = $merged->site_templates->get_available_site_templates();
+
+		$this->assertContains(2, $available, 'Template 2 should still be available after merging addon with null limit');
+		$this->assertContains(3, $available, 'Template 3 should still be available after merging addon with null limit');
+	}
+
+	/**
+	 * Test that null limit does overwrite in override mode.
+	 */
+	public function test_merge_null_limit_overwrites_in_override_mode(): void {
+
+		$base = new Limitations([
+			'users' => [
+				'enabled' => true,
+				'limit'   => 5,
+			],
+		]);
+
+		$override = new Limitations([
+			'users' => [
+				'enabled' => true,
+				'limit'   => null,
+			],
+		]);
+
+		$merged = $base->merge(true, $override);
+
+		$this->assertNull($merged->users->get_limit(), 'Null limit should overwrite in override mode');
+	}
+
+	/**
+	 * Test that get_empty returns proper default data in to_array.
+	 */
+	public function test_get_empty_to_array_returns_default_states(): void {
+
+		$empty = Limitations::get_empty();
+
+		$array = $empty->to_array();
+
+		$this->assertNotEmpty($array, 'get_empty()->to_array() should not be empty');
+		$this->assertArrayHasKey('site_templates', $array);
+		$this->assertArrayHasKey('plugins', $array);
+		$this->assertArrayHasKey('users', $array);
+	}
+
+	/**
+	 * Test full checkout scenario: plan templates preserved when merging with addon product.
+	 *
+	 * Simulates the validation rule in class-site-template.php where all product
+	 * limitations are merged together to determine available templates.
+	 */
+	public function test_checkout_plan_plus_addon_preserves_templates(): void {
+
+		// Plan with specific templates configured
+		$plan_data = new Limitations([
+			'site_templates' => [
+				'enabled' => true,
+				'mode'    => 'choose_available_templates',
+				'limit'   => [
+					'5' => ['behavior' => 'available'],
+					'7' => ['behavior' => 'available'],
+					'9' => ['behavior' => 'not_available'],
+				],
+			],
+			'disk_space'     => [
+				'enabled' => true,
+				'limit'   => 500,
+			],
+		]);
+
+		// Addon product with no template restrictions but some disk space
+		$addon_data = new Limitations([
+			'site_templates' => [
+				'enabled' => true,
+				'mode'    => 'default',
+				'limit'   => null,
+			],
+			'disk_space'     => [
+				'enabled' => true,
+				'limit'   => 100,
+			],
+		]);
+
+		// Simulate the validation rule merge
+		$limits = new Limitations([]);
+		$limits = $limits->merge($plan_data);
+		$limits = $limits->merge($addon_data);
+
+		$available = $limits->site_templates->get_available_site_templates();
+
+		$this->assertContains(5, $available, 'Template 5 should be available');
+		$this->assertContains(7, $available, 'Template 7 should be available');
+
+		// Disk space should be additive
+		$this->assertEquals(600, $limits->disk_space->get_limit(), 'Disk space should be summed');
+	}
 }