Try to parameterrize DOMAttr

Author: Girgias

stubs/dom.stub

@@ -31,9 +31,12 @@ class DOMNode
 {
 	/**
 	 * @readonly
-	 * @var DOMNamedNodeMap<DOMAttr>|null
+	 * @var DOMNamedNodeMap<DOMAttr<string>>|null
 	 */
 	public $attributes;
+
+	/** @phpstan-assert-if-true !null $this->attributes */
+	public function hasAttributes(): bool
 }
 
 class DOMElement extends DOMNode
@@ -42,6 +45,13 @@ class DOMElement extends DOMNode
 	/** @var DOMDocument */
 	public $ownerDocument;
 
+	/**
+	 * @readonly
+	 * @inherited
+	 * @var DOMNamedNodeMap<DOMAttr<string>>|null
+	 */
+	public $attributes;
+
 	/**
 	 * @param string $name
 	 * @return DOMNodeList<DOMElement>
@@ -55,6 +65,23 @@ class DOMElement extends DOMNode
 	 */
 	public function getElementsByTagNameNS ($namespaceURI, $localName) {}
 
+   /**
+    * @template T of string
+    * @param T $qualifiedName
+    * @return bool
+    * @phpstan-assert-if-true (T is 'xml:id' ? DOMNameSpaceNode : DOMAttr<T>) $this->hasAttribute($qualifiedName)
+    * @phpstan-assert-if-true DOMNameSpaceNode<DOMAttr<T>|DOMAttr<string>> $this->$attributes
+    */
+	public function hasAttribute(string $qualifiedName): bool
+
+	public function hasAttributeNS(?string $namespace, string $localName): bool
+
+   /**
+    * @template T of string
+    * @param T $qualifiedName
+    * @return (T is 'xml:id' ? DOMNameSpaceNode|false : DOMAttr|false)
+    */
+	public function getAttributeNode(string $qualifiedName): DOMAttr<T>|DOMNameSpaceNode|false
 }
 
 /**
@@ -86,12 +113,20 @@ class DOMXPath
 
 }
 
+/**
+ * @template Name as string
+ */
 class DOMAttr extends DOMNode
 {
-
 	/** @var DOMDocument */
 	public $ownerDocument;
 
+	/**
+	 * @var Name
+	 * @readonly
+	 */
+	public $name;
+
 }
 
 class DOMCharacterData extends DOMNode

tests/PHPStan/Rules/Properties/data/dom-legacy-ext-template-nodes.php

@@ -3,16 +3,24 @@
 use function PHPStan\Testing\assertType;
 
 function basic_node(\DOMNode $node): void {
-	assertType(DOMNamedNodeMap::class . '<' . DOMAttr::class . '>', $node->attributes);
+	if ($node->hasAttributes()) {
+		assertType(DOMNamedNodeMap::class . '<' . DOMAttr::class . '>', $node->attributes);
+	} else {
+		assertType('null', $node->attributes);
+	}
 };
 
-function element_node(\DOMElement $node): void
+function element_node(\DOMElement $element): void
 {
-	assertType(DOMNamedNodeMap::class . '<' . DOMAttr::class . '>', $node->attributes);
-	$attribute = $node->attributes->getNamedItem('class');
-	if ($attribute === null) {
-		return;
+	if ($element->hasAttribute('class')) {
+		assertType(DOMNamedNodeMap::class . '<' . DOMAttr::class . '>', $element->attributes);
+		$attribute = $element->attributes->getNamedItem('class');
+		if ($attribute === null) {
+			return;
+		}
+		assertType(DOMAttr::class, $attribute);
+		assertType('string', $attribute->value);
+	} else {
+		assertType('null', $element->attributes);
 	}
-	assertType(DOMAttr::class, $attribute);
-	assertType('string', $attribute->value);
 }