Introduce safe preg_split

Removes the need for extra assertions which makes the code
more readable, and reduces the overhead of an is_array check.

src/Exception/PcreException.php

@@ -0,0 +1,38 @@
+<?php
+
+declare(strict_types=1);
+
+namespace phpDocumentor\Reflection\Exception;
+
+use InvalidArgumentException;
+use const PREG_BACKTRACK_LIMIT_ERROR;
+use const PREG_BAD_UTF8_ERROR;
+use const PREG_BAD_UTF8_OFFSET_ERROR;
+use const PREG_INTERNAL_ERROR;
+use const PREG_JIT_STACKLIMIT_ERROR;
+use const PREG_NO_ERROR;
+use const PREG_RECURSION_LIMIT_ERROR;
+
+final class PcreException extends InvalidArgumentException
+{
+    public static function createFromPhpError(int $errorCode) : self
+    {
+        switch ($errorCode) {
+            case PREG_BACKTRACK_LIMIT_ERROR:
+                return new self('Backtrack limit error');
+            case PREG_RECURSION_LIMIT_ERROR:
+                return new self('Recursion limit error');
+            case PREG_BAD_UTF8_ERROR:
+                return new self('Bad UTF8 error');
+            case PREG_BAD_UTF8_OFFSET_ERROR:
+                return new self('Bad UTF8 offset error');
+            case PREG_JIT_STACKLIMIT_ERROR:
+                return new self('Jit stacklimit error');
+            case PREG_NO_ERROR:
+            case PREG_INTERNAL_ERROR:
+            default:
+        }
+
+        return new self('Unknown Pcre error');
+    }
+}