More tests and refactoring

src/Template/Twig.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace App\Template;
+
+use Twig\Environment;
+use Twig\Loader\ArrayLoader;
+use App\Template\TwigExtension;
+
+class Twig extends Environment
+{
+    /**
+     * @param string[] $templates Array of templates
+     */
+    public function __construct(array $templates)
+    {
+        $loader = new ArrayLoader($templates);
+        parent::__construct($loader);
+        $this->addExtension(new TwigExtension());
+    }
+}

src/Template/TwigExtension.php

@@ -0,0 +1,42 @@
+<?php
+
+namespace App\Template;
+
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Twig\Extension\AbstractExtension;
+use Twig\TwigFilter;
+
+/**
+ * Twig extension
+ *
+ * Additional formatters for templates
+ */
+class TwigExtension extends AbstractExtension
+{
+    /**
+     * Extend the filters
+     *
+     * @return TwigFilter[]
+     */
+    public function getFilters(): array
+    {
+        return array(
+            new TwigFilter('formatBytes', array($this, 'formatBytes')),
+        );
+    }
+
+    /**
+     * Format a file size to be human readable
+     *
+     * @param int $bytes     Number of bytes
+     * @param int $precision Precision
+     *
+     * @return string Formatted string
+     */
+    public function formatBytes($bytes, $precision = 2)
+    {
+        $size = ['B','kB','MB','GB','TB','PB','EB','ZB','YB'];
+        $fact = (int)(floor((strlen((string)$bytes) - 1) / 3));
+        return sprintf("%.{$precision}f", $bytes / pow(1024, $fact)) . $size[$fact];
+    }
+}