Add base URL resolution

lib/Parser/XML/Construct.php

@@ -155,7 +155,7 @@ abstract class Construct {
         }, $mediaTypes)))));
         $rels = $this->fetchAtomRelations($rel, $context);
         if ($rels && !$mediaTypes) {
-            return new Url($rels[0]->getAttribute("href"), );
+            return new Url($rels[0]->getAttribute("href"), $rels[0]->baseURI);
         }
         $result = array_reduce($rels, function($best, $cur) use ($mediaTypes) {
             $t = trim($cur->getAttribute("type"));
@@ -175,7 +175,7 @@ abstract class Construct {
             }
             return $best;
         });
-        return $result ? new Url($result[0]->getAttribute("href")) : null;
+        return $result ? new Url($result[0]->getAttribute("href"), $result[0]->baseURI) : null;
     }
 
     /** Primitive to fetch an Atom feed/entry identifier */

lib/Parser/XML/Feed.php

@@ -44,7 +44,7 @@ class Feed extends Construct implements \MensBeam\Lax\Parser\Feed {
         if (!$this->document->loadXML($this->data, self::LIBXML_OPTIONS)) {
             throw new Exception("notXML");
         }
-        $this->document->documentURI = (string) $this->url;
+        $this->document->documentURI = $this->url;
         $this->xpath = new XPath($this->document);
         $this->subject = $this->document->documentElement;
         $ns = $this->subject->namespaceURI;

tests/cases/XML/feed-atom.yaml

@@ -163,3 +163,16 @@ Feed link 9: # The first matching relation wins
         format: atom
         version: '1.0'
         link: 'http://example.com/'
+
+Relative feed link:
+    doc_url: 'http://example.com/path/'
+    input: >
+        <feed xmlns="http://www.w3.org/2005/Atom">
+          <link href="/"/>
+        </feed>
+    output:
+        format: atom
+        version: '1.0'
+        meta:
+            url: 'http://example.com/path/'
+        link: ['/', 'http://example.com/path/']