Added another test

Author: LasseRafn

src/Exceptions/PercentageIsNotAnInteger.php

@@ -0,0 +1,7 @@
+<?php
+
+namespace LasseRafn\Hexer\Exceptions;
+
+class PercentageIsNotAnInteger extends \Exception
+{
+}

src/Hex.php

@@ -4,6 +4,7 @@
 
 use LasseRafn\Hexer\Exceptions\HexTooLongException;
 use LasseRafn\Hexer\Exceptions\HexTooShortException;
+use LasseRafn\Hexer\Exceptions\PercentageIsNotAnInteger;
 use LasseRafn\Hexer\Exceptions\PercentageTooHighException;
 use LasseRafn\Hexer\Exceptions\PercentageTooLowException;
 
@@ -55,8 +56,19 @@ public function darken($percentage = 0)
         return $this->brightnessModifier->adjustBrightness($this->hex, $percentage * -1);
     }
 
+	/**
+	 * @param integer $percentage
+	 *
+	 * @throws PercentageTooHighException
+	 * @throws PercentageTooLowException
+	 * @throws PercentageIsNotAnInteger
+	 */
     private function validatePercentage($percentage)
     {
+    	if( ! is_int($percentage)) {
+			throw new PercentageIsNotAnInteger("The percentage ({$percentage}) is not an integer.");
+	    }
+
         if ($percentage < 0) {
             throw new PercentageTooLowException("The percentage ({$percentage}) is below zero (0)");
         }
@@ -66,6 +78,10 @@ private function validatePercentage($percentage)
         }
     }
 
+	/**
+	 * @throws HexTooLongException
+	 * @throws HexTooShortException
+	 */
     private function validateHex()
     {
         $hex = str_replace('#', '', $this->hex);

tests/HexModifierTest.php

@@ -100,6 +100,14 @@ public function test_will_fail_with_too_high_percentage_input()
         $hex->lighten(101);
     }
 
+    public function test_will_fail_with_a_non_integer_percentage_input()
+    {
+        $this->expectException(\LasseRafn\Hexer\Exceptions\PercentageIsNotAnInteger::class);
+
+        $hex = new \LasseRafn\Hexer\Hex('#fff');
+        $hex->lighten('ab12');
+    }
+
     public function test_will_return_initial_hex_with_zero_percentage()
     {
         $hex = new \LasseRafn\Hexer\Hex('#fff');