Better compatability with the old addLink()

Author: Grotax

src/FeedIo/Rule/Atom/LinkNode.php

@@ -49,6 +49,11 @@ protected function addElement(DomDocument $document, DOMElement $rootElement, No
 
         if ($node instanceof FeedInterface && $this->hasFeedLinks($node)) {
             $this->addFeedLinks($document, $rootElement, $node);
+
+            if ($node->getLink() !== null && !$this->hasFeedLinkForHref($node, $node->getLink())) {
+                $this->ruleSet->getDefault()->apply($document, $rootElement, $node);
+            }
+
             return;
         }
 
@@ -64,6 +69,17 @@ protected function hasFeedLinks(FeedInterface $feed): bool
         return false;
     }
 
+    protected function hasFeedLinkForHref(FeedInterface $feed, string $href): bool
+    {
+        foreach ($feed->getLinks() as $feedLink) {
+            if ($feedLink->getHref() === $href) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
     protected function addFeedLinks(DomDocument $document, DOMElement $rootElement, FeedInterface $feed): void
     {
         foreach ($feed->getLinks() as $feedLink) {

tests/FeedIo/Rule/Atom/LinkNodeTest.php

@@ -70,7 +70,8 @@ public function testCreateElement()
 
         $addedElement = $rootElement->firstChild;
 
-        $this->assertInstanceOf('\DomElement', $addedElement);
+        $this->assertInstanceOf(\DOMElement::class, $addedElement);
+        /** @var \DOMElement $addedElement */
         $this->assertEquals(self::LINK, $addedElement->getAttribute('href'));
         $this->assertEquals('link', $addedElement->nodeName);
 
@@ -137,6 +138,27 @@ public function testFeedWithoutLinksCollectionFallsBackToDefault()
         );
     }
 
+    public function testLegacyLinkIsPreservedWhenFeedLinksArePresent()
+    {
+        $feed = new \FeedIo\Feed();
+        $feed->setLink('https://example.com/');
+        $feed->addLink('self', 'https://example.com/feed.atom');
+
+        $document = new \DOMDocument();
+        $rootElement = $document->createElement('feed');
+        $this->object->apply($document, $rootElement, $feed);
+
+        $document->appendChild($rootElement);
+
+        $this->assertXmlStringEqualsXmlString(
+            '<feed>'
+            . '<link rel="self" href="https://example.com/feed.atom"/>'
+            . '<link href="https://example.com/"/>'
+            . '</feed>',
+            $document->saveXML()
+        );
+    }
+
     public function testSetHomePageUrlAndFeedUrlEmitsMultipleLinks()
     {
         $feed = new \FeedIo\Feed();