convert hostnames to lowercase

lib/helpers.php

@@ -5,9 +5,26 @@ function view($template, $data=[]) {
   return $templates->render($template, $data);
 }
 
-// Adds slash if no path is in the URL
+// Adds slash if no path is in the URL, and convert hostname to lowercase
 function normalize_url($url) {
-  return parse_url($url, PHP_URL_PATH) == '' ? $url.'/' : $url;
+  $parts = parse_url($url);
+  if(empty($parts['path']))
+    $parts['path'] = '/';
+  $parts['host'] = strtolower($parts['host']);
+  return build_url($parts);
+}
+
+function build_url($parsed_url) {
+  $scheme   = isset($parsed_url['scheme']) ? $parsed_url['scheme'] . '://' : '';
+  $host     = isset($parsed_url['host']) ? $parsed_url['host'] : '';
+  $port     = isset($parsed_url['port']) ? ':' . $parsed_url['port'] : '';
+  $user     = isset($parsed_url['user']) ? $parsed_url['user'] : '';
+  $pass     = isset($parsed_url['pass']) ? ':' . $parsed_url['pass']  : '';
+  $pass     = ($user || $pass) ? "$pass@" : '';
+  $path     = isset($parsed_url['path']) ? $parsed_url['path'] : '';
+  $query    = isset($parsed_url['query']) ? '?' . $parsed_url['query'] : '';
+  $fragment = isset($parsed_url['fragment']) ? '#' . $parsed_url['fragment'] : '';
+  return "$scheme$user$pass$host$port$path$query$fragment";
 }
 
 function should_follow_redirects($url) {

tests/HelpersTest.php

@@ -0,0 +1,16 @@
+<?php
+class HelpersTest extends PHPUnit_Framework_TestCase {
+
+  public function testLowercaseHostname() {
+    $url = 'http://Example.com/';
+    $result = normalize_url($url);
+    $this->assertEquals('http://example.com/', $result);
+  }
+
+  public function testAddsSlashToBareDomain() {
+    $url = 'http://example.com';
+    $result = normalize_url($url);
+    $this->assertEquals('http://example.com/', $result);
+  }
+
+}