fix: bindable cache memory efficiency when using nested parent objects

fixes #495

src/BindableCache.php

@@ -31,7 +31,7 @@ public function __construct() {
 		$this->nonBindableClassMap = [];
 	}
 
-	public function isBindable(object $object):bool {
+	public function isBindable(object $object, bool $recursive = false):bool {
 		$refObj = null;
 
 		if($object instanceof ReflectionClass) {
@@ -115,6 +115,7 @@ public function isBindable(object $object):bool {
 			return false;
 		}
 
+		$this->bindableClassMap[$classString] = $attributeCache;
 		$attributeCache = $this->expandObjects(
 			$attributeCache,
 			$cacheObjectKeys,
@@ -137,14 +138,14 @@ private function expandObjects(array $cache, array $objectKeys):array {
 		foreach($cache as $key => $closure) {
 			if($objectType = $objectKeys[$key] ?? null) {
 				$refClass = new ReflectionClass($objectType);
-				if($this->isBindable($refClass)) {
+				$refClassName = $refClass->getName();
+
+				if(isset($this->bindableClassMap[$refClassName]) || $this->isBindable($refClass)) {
 					$bindable = $this->bindableClassMap[$objectType];
 					foreach($bindable as $bindableKey => $bindableClosure) {
 						$cache["$key.$bindableKey"] = $bindableClosure;
 					}
 				}
-
-//				unset($cache[$key]);
 			}
 		}
 

test/phpunit/BindableCacheTest.php

@@ -5,6 +5,9 @@
 use Gt\DomTemplate\BindGetter;
 use Gt\DomTemplate\BindableCache;
 use Gt\DomTemplate\BindGetterMethodDoesNotStartWithGetException;
+use Gt\DomTemplate\Test\TestHelper\Model\Address;
+use Gt\DomTemplate\Test\TestHelper\Model\Customer;
+use Gt\DomTemplate\Test\TestHelper\Model\Order;
 use Gt\DomTemplate\Test\TestHelper\TestData;
 use PHPUnit\Framework\TestCase;
 use stdClass;
@@ -178,6 +181,15 @@ public function testConvertToKvp_nestedObject():void {
 		}
 	}
 
+	public function testConvertKvp_nestedObjectSameType():void {
+		$sut = new BindableCache();
+		$parentCustomer = new Customer(100, "Parent Customer");
+		$customer = new Customer(101, "Test Customer", parentCustomer: $parentCustomer);
+		$kvp = $sut->convertToKvp($customer);
+		self::assertSame("101", $kvp["id"]);
+		self::assertSame("Test Customer", $kvp["name"]);
+	}
+
 	public function testConvertToKvp_nestedNullProperty():void {
 		$sut = new BindableCache();
 

test/phpunit/TestHelper/Model/Customer.php

@@ -8,6 +8,7 @@ public function __construct(
 		public string $name,
 		public ?Address $address = null,
 		public array $orderList = [],
+		public ?Customer $parentCustomer = null,
 	) {}
 
 	public function addOrder(Order $order):void {