Use NodeIterator to optimize additional listeners

Author: colinodell

src/Extension/DescriptionList/Event/ConsecutiveDescriptionListMerger.php

@@ -15,35 +15,27 @@
 
 use League\CommonMark\Event\DocumentParsedEvent;
 use League\CommonMark\Extension\DescriptionList\Node\DescriptionList;
+use League\CommonMark\Node\NodeIterator;
 
 final class ConsecutiveDescriptionListMerger
 {
     public function __invoke(DocumentParsedEvent $event): void
     {
-        $walker = $event->getDocument()->walker();
-        while ($e = $walker->next()) {
-            // Wait until we're exiting a description list node
-            if ($e->isEntering()) {
-                continue;
-            }
-
-            $node = $e->getNode();
+        foreach ($event->getDocument()->iterator(NodeIterator::FLAG_BLOCKS_ONLY) as $node) {
             if (! $node instanceof DescriptionList) {
                 continue;
             }
 
-            if (! ($next = $node->next()) instanceof DescriptionList) {
+            if (! ($prev = $node->previous()) instanceof DescriptionList) {
                 continue;
             }
 
-            // There's another description list next; merge it into the current one
-            foreach ($next->children() as $child) {
-                $node->appendChild($child);
+            // There's another description list behind this one; merge the current one into that
+            foreach ($node->children() as $child) {
+                $prev->appendChild($child);
             }
 
-            $next->detach();
-
-            $walker->resumeAt($node, false);
+            $node->detach();
         }
     }
 }

src/Extension/DescriptionList/Event/LooseDescriptionHandler.php

@@ -19,19 +19,13 @@
 use League\CommonMark\Extension\DescriptionList\Node\DescriptionTerm;
 use League\CommonMark\Node\Block\Paragraph;
 use League\CommonMark\Node\Inline\Newline;
+use League\CommonMark\Node\NodeIterator;
 
 final class LooseDescriptionHandler
 {
     public function __invoke(DocumentParsedEvent $event): void
     {
-        $walker = $event->getDocument()->walker();
-        while ($e = $walker->next()) {
-            // Wait until we're exiting a node
-            if ($e->isEntering()) {
-                continue;
-            }
-
-            $description = $e->getNode();
+        foreach ($event->getDocument()->iterator(NodeIterator::FLAG_BLOCKS_ONLY) as $description) {
             if (! $description instanceof Description) {
                 continue;
             }

src/Extension/TableOfContents/TableOfContentsBuilder.php

@@ -71,19 +71,25 @@ public function onDocumentParsed(DocumentParsedEvent $event): void
 
     private function insertBeforeFirstLinkedHeading(Document $document, TableOfContents $toc): void
     {
-        foreach ($document->iterator() as $node) {
-            if ($node instanceof HeadingPermalink && ($parent = $node->parent()) instanceof Heading) {
-                $parent->insertBefore($toc);
+        foreach ($document->iterator(NodeIterator::FLAG_BLOCKS_ONLY) as $node) {
+            if (! $node instanceof Heading) {
+                continue;
+            }
+
+            foreach ($node->children() as $child) {
+                if ($child instanceof HeadingPermalink) {
+                    $node->insertBefore($toc);
 
-                return;
+                    return;
+                }
             }
         }
     }
 
     private function replacePlaceholders(Document $document, TableOfContents $toc): void
     {
         foreach ($document->iterator(NodeIterator::FLAG_BLOCKS_ONLY) as $node) {
-            // Add the block once we find a placeholder (and we're about to leave it)
+            // Add the block once we find a placeholder
             if (! $node instanceof TableOfContentsPlaceholder) {
                 continue;
             }

src/Extension/TableOfContents/TableOfContentsGenerator.php

@@ -25,6 +25,7 @@
 use League\CommonMark\Extension\TableOfContents\Normalizer\NormalizerStrategyInterface;
 use League\CommonMark\Extension\TableOfContents\Normalizer\RelativeNormalizerStrategy;
 use League\CommonMark\Node\Block\Document;
+use League\CommonMark\Node\NodeIterator;
 use League\CommonMark\Node\RawMarkupContainerInterface;
 use League\CommonMark\Node\StringContainerHelper;
 use League\Config\Exception\InvalidConfigurationException;
@@ -130,9 +131,15 @@ private function createToc(Document $document): TableOfContents
      */
     private function getHeadingLinks(Document $document): iterable
     {
-        foreach ($document->iterator() as $node) {
-            if ($node instanceof HeadingPermalink) {
-                yield $node;
+        foreach ($document->iterator(NodeIterator::FLAG_BLOCKS_ONLY) as $node) {
+            if (! $node instanceof Heading) {
+                continue;
+            }
+
+            foreach ($node->children() as $child) {
+                if ($child instanceof HeadingPermalink) {
+                    yield $child;
+                }
             }
         }
     }