Added local file link provider

tests/units/ExternalLink/FileLinkTest.php

@@ -0,0 +1,28 @@
+<?php
+
+require_once __DIR__.'/../Base.php';
+
+use Kanboard\ExternalLink\FileLink;
+
+class FileLinkTest extends Base
+{
+    public function testGetTitleFromUrlWithUnixPath()
+    {
+        $url = 'file:///tmp/test.txt';
+
+        $link = new FileLink($this->container);
+        $link->setUrl($url);
+        $this->assertEquals($url, $link->getUrl());
+        $this->assertEquals('test.txt', $link->getTitle());
+    }
+
+    public function testGetTitleFromUrlWithWindowsPath()
+    {
+        $url = 'file:///c:\temp\test.txt';
+
+        $link = new FileLink($this->container);
+        $link->setUrl($url);
+        $this->assertEquals($url, $link->getUrl());
+        $this->assertEquals('test.txt', $link->getTitle());
+    }
+}