also check for opening rss tag

closes #89

lib/XRay/Parser.php

@@ -63,6 +63,12 @@ class Parser {
       return Formats\XML::parse($http_response);
     }
 
+    // Some feeds don't start with <?xml
+    $begin = trim(substr($body, 0, 40));
+    if(substr($begin, 0, 4) == '<rss') {
+      return Formats\XML::parse($http_response);
+    }
+
     if(substr($body, 0, 1) == '{') {
       $parsed = json_decode($body, true);
       if($parsed && isset($parsed['version']) && $parsed['version'] == 'https://jsonfeed.org/version/1') {

tests/FeedTest.php

@@ -465,4 +465,14 @@ class FeedTest extends PHPUnit_Framework_TestCase {
     $this->assertEquals('Barnaby Walters', $item->author->name);
     $this->assertEquals('https://waterpigs.co.uk', $item->author->url);
   }
+
+  public function testRSSWithNoXMLTag() {
+    $url = 'http://feed.example.com/rss-no-xml-tag';
+    $response = $this->parse(['url' => $url, 'expect' => 'feed']);
+    $body = $response->getContent();
+    $this->assertEquals(200, $response->getStatusCode());
+    $data = json_decode($body)->data;
+
+    $this->assertEquals('feed', $data->type);
+  }
 }