add breakpoint tests

Author: Martin Smeeckaert

spec/Coduo/PHPHumanizer/String/WordBreakpointSpec.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace spec\Coduo\PHPHumanizer\String;
+
+use Coduo\PHPHumanizer\String\WordBreakpoint;
+use PhpSpec\ObjectBehavior;
+use Prophecy\Argument;
+
+class WordBreakpointSpec extends ObjectBehavior
+{
+
+    function it_breakpoint()
+    {
+        $text = 'Lorem ipsum dolorem si amet, lorem ipsum. Dolorem sic et nunc.';
+
+        $this->calculatePosition($text, 2)->shouldReturn(5);
+        $this->calculatePosition($text, 4)->shouldReturn(5);
+        $this->calculatePosition($text, 5)->shouldReturn(5);
+        $this->calculatePosition($text, 10)->shouldReturn(11);
+        $this->calculatePosition($text, 20)->shouldReturn(22);
+        $this->calculatePosition($text, -2)->shouldReturn(-2);
+        $this->calculatePosition($text, 0)->shouldReturn(5);
+    }
+
+}

src/Coduo/PHPHumanizer/String/WordBreakpoint.php

@@ -7,7 +7,7 @@ class WordBreakpoint implements Breakpoint
     public function calculatePosition($text, $charactersCount)
     {
         $length = $charactersCount;
-        if (false !== ($breakpoint = mb_strpos($text, ' ', $charactersCount))) {
+        if ($charactersCount >= 0 && false !== ($breakpoint = mb_strpos($text, ' ', $charactersCount))) {
             $length = $breakpoint;
         }
         return $length;