IOPS-1870 Allow Van as surname when only surname

It was detected that Van was always detected as prefix of surname.
However, it did not make sense to have a prefix without a surname.
This PR fixes that, it checks if it is the only surname and if it
is, it get the only surname as surname without paying attention
to the prefixes.

src/Mapper/LastnameMapper.php

@@ -64,7 +64,9 @@ protected function mapReversedParts(array $parts): array
                 break;
             }
 
-            $parts[$k] = new Lastname($part);
+            $lastname = new Lastname($part);
+            $lastname->setAsNotPrefix();
+            $parts[$k] = $lastname;
         }
 
         return $parts;

src/Part/Lastname.php

@@ -24,6 +24,8 @@ class Lastname extends AbstractPart
         'la' => 'la',
         'ter' => 'ter'
     ];
+    /** @var bool */
+    private $checkForPrefixes = true;
 
     /**
      * check if the given word is a lastname prefix
@@ -57,10 +59,15 @@ public function normalize()
     {
         $value = $this->getValue();
 
-        if (self::isPrefix($value)) {
+        if ($this->checkForPrefixes && self::isPrefix($value)) {
             return static::$prefixes[self::getKey($value)];
         }
 
         return $this->camelcase($this->getValue());
     }
+
+    public function setAsNotPrefix()
+    {
+        $this->checkForPrefixes = false;
+    }
 }

tests/ParserTest.php

@@ -319,6 +319,13 @@ public function provider()
                     'lastname' => 'Truong',
                 ],
             ],
+            [
+                'John Van',
+                [
+                    'firstname' => 'John',
+                    'lastname' => 'Van',
+                ],
+            ],
             [
                 'Mr. Van Truong',
                 [