Fix collection items colliding when they share a basename

src/Collection/Collection.php

@@ -5,6 +5,7 @@
 use Closure;
 use Illuminate\Support\Arr;
 use Illuminate\Support\Collection as BaseCollection;
+use Illuminate\Support\Str;
 use TightenCo\Jigsaw\IterableObject;
 
 class Collection extends BaseCollection
@@ -29,12 +30,19 @@ public function loadItems(BaseCollection $items)
             ->map($this->getMap())
             ->filter($this->getFilter())
             ->keyBy(function ($item) {
-                return $item->getFilename();
+                return self::itemKey($item->getRelativePath(), $item->getFilename());
             });
 
         return $this->updateItems($this->addAdjacentItems($sortedItems));
     }
 
+    public static function itemKey($relativePath, $filename)
+    {
+        return $relativePath && ! Str::startsWith($relativePath, '_')
+            ? $relativePath . '/' . $filename
+            : $filename;
+    }
+
     public function updateItems(BaseCollection $items)
     {
         $this->items = $this->getArrayableItems($items);
@@ -46,7 +54,7 @@ private function addAdjacentItems(BaseCollection $items)
     {
         $count = $items->count();
         $adjacentItems = $items->map(function ($item) {
-            return $item->getFilename();
+            return self::itemKey($item->getRelativePath(), $item->getFilename());
         });
         $previousItems = $adjacentItems->prepend(null)->take($count);
         $nextItems = $adjacentItems->push(null)->take(-$count);

src/File/InputFile.php

@@ -42,6 +42,13 @@ public function topLevelDirectory()
         return count($parts) == 1 ? '' : $parts[0];
     }
 
+    public function getRelativePathBelowTopLevel()
+    {
+        $relativePath = str_replace('\\', '/', $this->file->getRelativePath());
+
+        return ltrim((string) Str::after($relativePath, $this->topLevelDirectory()), '/');
+    }
+
     public function getFilenameWithoutExtension()
     {
         return $this->getBasename('.' . $this->getFullExtension());

src/Handlers/CollectionItemHandler.php

@@ -6,6 +6,7 @@
 use Illuminate\Support\Collection;
 use Illuminate\Support\Str;
 use TightenCo\Jigsaw\Builders\PlainMarkdownBuilder;
+use TightenCo\Jigsaw\Collection\Collection as JigsawCollection;
 use TightenCo\Jigsaw\File\OutputFile;
 use TightenCo\Jigsaw\Parsers\FrontMatterParser;
 
@@ -56,7 +57,10 @@ public function handle($file, $pageData)
             return $handler->shouldHandle($file);
         });
         $collectionName = $this->getCollectionName($file);
-        $pageData->setPageVariableToCollectionItem($collectionName, $file->getFilenameWithoutExtension());
+        $pageData->setPageVariableToCollectionItem(
+            $collectionName,
+            JigsawCollection::itemKey($file->getRelativePathBelowTopLevel(), $file->getFilenameWithoutExtension()),
+        );
 
         if ($pageData->page === null) {
             return null;

tests/CollectionItemTest.php

@@ -201,6 +201,32 @@ public function collection_item_view_path_for_flat_items_equals_filename()
         );
     }
 
+    #[Test]
+    public function collection_items_with_same_basename_in_different_directories_do_not_collide()
+    {
+        $config = collect(['collections' => [
+            'collection' => [
+                'path' => 'collection/{relativePath}/{filename}',
+            ],
+        ]]);
+        $files = $this->setupSource([
+            '_layouts' => [
+                'item.blade.php' => '@section(\'content\') @endsection',
+            ],
+            '_collection' => [
+                'page.blade.php' => "@extends('_layouts.item')\nROOT",
+                'nested' => [
+                    'page.blade.php' => "@extends('_layouts.item')\nNESTED",
+                ],
+            ],
+        ]);
+
+        $this->buildSite($files, $config);
+
+        $this->assertEquals('ROOT', trim($files->getChild('build/collection/page.html')->getContent()));
+        $this->assertEquals('NESTED', trim($files->getChild('build/collection/nested/page.html')->getContent()));
+    }
+
     #[Test]
     public function collection_item_page_metadata_contains_extension()
     {