fix(PropFind): Include handle() props in d:allprop PROPFINDs

lib/DAV/PropFind.php

@@ -90,7 +90,23 @@ public function __construct($path, array $properties, $depth = 0, $requestType =
      */
     public function handle($propertyName, $valueOrCallBack)
     {
-        if ($this->itemsLeft && isset($this->result[$propertyName]) && 404 === $this->result[$propertyName][0]) {
+        // If this is an ALLPROPS request and the property is
+        // unknown, add it to the result; else ignore it:
+        if (!isset($this->result[$propertyName])) {
+            if (self::ALLPROPS === $this->requestType) {
+                if (is_callable($valueOrCallBack)) {
+                    $value = $valueOrCallBack();
+                } else {
+                    $value = $valueOrCallBack;
+                }
+
+                $this->result[$propertyName] = [200, $value];
+            }
+
+            return;
+        }
+
+        if ($this->itemsLeft && 404 === $this->result[$propertyName][0]) {
             if (is_callable($valueOrCallBack)) {
                 $value = $valueOrCallBack();
             } else {

tests/Sabre/DAV/PropFindTest.php

@@ -52,9 +52,13 @@ public function testSetAllpropCustom()
     {
         $propFind = new PropFind('foo', ['{DAV:}displayname'], 0, PropFind::ALLPROPS);
         $propFind->set('{DAV:}customproperty', 'bar');
+        $propFind->handle('{DAV:}otherproperty', fn () => 'baz');
 
         self::assertEquals([
-            200 => ['{DAV:}customproperty' => 'bar'],
+            200 => [
+                '{DAV:}customproperty' => 'bar',
+                '{DAV:}otherproperty' => 'baz',
+            ],
         ], $propFind->getResultForMultiStatus());
     }