Catch various validation errors

app/Support/Request/ConvertsDataTypes.php

@@ -46,10 +46,11 @@ trait ConvertsDataTypes
      * Abstract method that always exists in the Request classes that use this
      * trait, OR a stub needs to be added by any other class that uses this train.
      *
-     * @param mixed $key
+     * @param  mixed  $key
      * @return mixed
      */
     abstract public function has($key);
+
     /**
      * Return integer value.
      *
@@ -71,7 +72,11 @@ trait ConvertsDataTypes
      */
     public function convertString(string $field): string
     {
-        return $this->clearString((string)($this->get($field) ?? ''), false);
+        $entry = $this->get($field);
+        if (!is_scalar($entry)) {
+            return '';
+        }
+        return $this->clearString((string)$entry, false);
     }
 
     /**
@@ -85,7 +90,9 @@ trait ConvertsDataTypes
         if (null === $string) {
             return null;
         }
-        $search       = [
+        var_dump($string);
+
+        $search  = [
             "\0", // NUL
             "\f", // form feed
             "\v", // vertical tab
@@ -135,14 +142,17 @@ trait ConvertsDataTypes
             "\u{3000}", // ideographic space
             "\u{FEFF}", // zero width no -break space
         ];
-        $replace      = "\x20"; // plain old normal space
-        $string       = str_replace($search, $replace, $string);
+        $replace = "\x20"; // plain old normal space
+        $string  = str_replace($search, $replace, $string);
+
         $secondSearch = $keepNewlines ? ["\r"] : ["\r", "\n", "\t", "\036", "\025"];
         $string       = str_replace($secondSearch, '', $string);
 
         // clear zalgo text (TODO also in API v2)
         $string = preg_replace('/\pM/u', '', $string);
-
+        if (null === $string) {
+            return null;
+        }
         return trim($string);
     }