Improve check for empty property names

Specfically avoid the property name "0" crashes the parser with a 'LogicException: This code should not be reachable'

Author: kristoffermollerhoj

lib/Parser/MimeDir.php

@@ -417,7 +417,7 @@ protected function readProperty($line)
                 $property['value'] = $match['propValue'];
                 continue;
             }
-            if (isset($match['name']) && $match['name']) {
+            if (isset($match['name']) && 0 < strlen($match['name'])) {
                 $property['name'] = strtoupper($match['name']);
                 continue;
             }
@@ -430,7 +430,7 @@ protected function readProperty($line)
         if (is_null($property['value'])) {
             $property['value'] = '';
         }
-        if (!$property['name']) {
+        if (!isset($property['name']) || 0 == strlen($property['name'])) {
             if ($this->options & self::OPTION_IGNORE_INVALID_LINES) {
                 return false;
             }

tests/VObject/Parser/MimeDirTest.php

@@ -263,4 +263,21 @@ public function provideBrokenVCalendar()
 EOF
         ]];
     }
+
+    public function testPropertyName0(): void
+    {
+        $iCal = <<<EOF
+BEGIN:VCALENDAR
+VERSION:2.0
+PRODID:PRODID
+BEGIN:VEVENT
+0:test
+END:VEVENT
+END:VCALENDAR
+EOF;
+
+        $mimeDir = new MimeDir();
+        $vevent = $mimeDir->parse($iCal);
+        self::assertEquals('test', $vevent->VEVENT->{0}->getValue());
+    }
 }