Fix a bug in the Item constructor parameter listHEADmaster

The id parameter of the Pagelet and Resource constructor doesn't accept
NULL values anymore (since 76cdd118d68bda3b7b29b192c7bf3d6e02bd6079).

Therefore, allow NULL values by using the parameter type "?string"
instead of "string" to allow either string values or NULL.

4 files changed, 4 insertions, 4 deletions

diff --git a/include/classes/BigPipe/Pagelet.php b/include/classes/BigPipe/Pagelet.php
index daca9df..d6f2103 100644
--- a/include/classes/BigPipe/Pagelet.php
+++ b/include/classes/BigPipe/Pagelet.php
@@ -35,7 +35,7 @@ class Pagelet extends Item {
 	const PHASE_LOADJS  = 3; # After all the JS resources have been loaded
 	const PHASE_DONE    = 4; # After the static JS code has been executed
 
-	public function __construct(string $id = NULL, int $priority = self::PRIORITY_NORMAL) {
+	public function __construct(?string $id = NULL, int $priority = self::PRIORITY_NORMAL) {
 		$this->id = $id ?? spl_object_hash($this);
 
 		$this->priority    = $priority;
diff --git a/include/classes/BigPipe/Resource.php b/include/classes/BigPipe/Resource.php
index 92b61ef..b6f3b8c 100644
--- a/include/classes/BigPipe/Resource.php
+++ b/include/classes/BigPipe/Resource.php
@@ -33,7 +33,7 @@ abstract class Resource extends Item {
 	#===============================================================================
 	# Build resource
 	#===============================================================================
-	public function __construct(string $id, int $type, string $url) {
+	public function __construct(?string $id, int $type, string $url) {
 		$this->id = $id ?? spl_object_hash($this);
 		$this->type = $type;
 		$this->url = $url;
diff --git a/include/classes/BigPipe/Resource/Javascript.php b/include/classes/BigPipe/Resource/Javascript.php
index b549075..6a9d492 100644
--- a/include/classes/BigPipe/Resource/Javascript.php
+++ b/include/classes/BigPipe/Resource/Javascript.php
@@ -13,7 +13,7 @@ class Javascript extends \BigPipe\Resource {
 	#===============================================================================
 	# Build resource
 	#===============================================================================
-	public function __construct(string $id, string $url) {
+	public function __construct(?string $id, string $url) {
 		parent::__construct($id, parent::TYPE_JAVASCRIPT, $url);
 	}
 
diff --git a/include/classes/BigPipe/Resource/Stylesheet.php b/include/classes/BigPipe/Resource/Stylesheet.php
index a5998df..9f4afba 100644
--- a/include/classes/BigPipe/Resource/Stylesheet.php
+++ b/include/classes/BigPipe/Resource/Stylesheet.php
@@ -13,7 +13,7 @@ class Stylesheet extends \BigPipe\Resource {
 	#===============================================================================
 	# Build resource
 	#===============================================================================
-	public function __construct(string $id, string $url) {
+	public function __construct(?string $id, string $url) {
 		parent::__construct($id, parent::TYPE_STYLESHEET, $url);
 	}