add some new method for int helper

Author: inhere

src/Helper/DataHelper.php

@@ -67,8 +67,6 @@ public static function toBool($val, $nullAsFalse = false): bool
      */
     public static function toString($val): string
     {
-        // print_r($value)
-        // var_export($value)
         if (is_scalar($val)) {
             if (is_bool($val)) {
                 return $val ? 'bool(TRUE)' : 'bool(FALSE)';
@@ -77,6 +75,11 @@ public static function toString($val): string
             return (string)$val;
         }
 
+        // TIP: null is not scalar type.
+        if ($val === null) {
+            return 'NULL';
+        }
+
         if (is_array($val)) {
             return json_encode($val);
         }

src/Helper/IntHelper.php

@@ -30,6 +30,17 @@ public static function getMax(int $val1, int $val2): int
         return $val1 > $val2 ? $val1 : $val2;
     }
 
+    /**
+     * @param int $val1
+     * @param int $val2
+     *
+     * @return int
+     */
+    public static function getMin(int $val1, int $val2): int
+    {
+        return $val1 < $val2 ? $val1 : $val2;
+    }
+
     // ----- http://cn2.php.net/manual/zh/function.pack.php#119402
 
     /**