Explicitly check for valid input data (#231)

When comparing CSV data with DB rows, the method now throws a
ValueError exception if a column is defined in CSV but does not
exist in DB row.

Classes/Core/Functional/FunctionalTestCase.php

@@ -747,6 +747,10 @@ protected function getDifferentFields(array $assertion, array $record): array
                 continue;
             }
 
+            if (!array_key_exists($field, $record)) {
+                throw new \ValueError(sprintf('"%s" column not found in the input data.', $field));
+            }
+
             if (strpos($value, '<?xml') === 0) {
                 try {
                     $this->assertXmlStringEqualsXmlString((string)$value, (string)$record[$field]);