fix: handle key column not present in pagination cursor (#41)

* fix: keyName column may not be present in pagination cursor
* test: add test to cover with Id Encoding combined with withoutKeySort behaviour

---------

Co-authored-by: Gregory Haddow <[email protected]>

Author: haddowg

src/Pagination/Cursor/CursorParser.php

@@ -32,12 +32,13 @@ public function __construct(private IdParser $idParser, private string $keyName)
      */
     public function encode(LaravelCursor $cursor): string
     {
-        $key = $cursor->parameter($this->keyName);
-
-        if ($key) {
+        try {
+            $key = $cursor->parameter($this->keyName);
             $parameters = $this->withoutPrivate($cursor->toArray());
             $parameters[$this->keyName] = $this->idParser->encode($key);
             $cursor = new LaravelCursor($parameters, $cursor->pointsToNextItems());
+        } catch (\UnexpectedValueException $ex) {
+           // Do nothing as the cursor does not contain the key.
         }
 
         return $cursor->encode();

tests/lib/Acceptance/Pagination/CursorPaginationTest.php

@@ -275,6 +275,57 @@ public function testWithoutCursor(): void
         $this->assertPage($posts->reverse()->take(3), $page);
     }
 
+    /**
+     * @return void
+     */
+    public function testWithIdEncodingWithoutKeySort(): void
+    {
+        $this->withIdEncoding();
+        $this->paginator->withoutKeySort();
+
+        $posts = Post::factory()->count(4)->sequence(['title' => 'd'], ['title' => 'c'], ['title' => 'b'], ['title' => 'a'])->create();
+
+        $meta = [
+            'from' => $this->encodeCursor(
+                ["posts.title"=> "a"],
+                pointsToNextItems: false,
+            ),
+            'hasMore' => true,
+            'perPage' => 3,
+            'to' => $this->encodeCursor(
+                ["posts.title"=> "c"],
+                pointsToNextItems: true,
+            ),
+        ];
+
+        $links = [
+            'first' => [
+                'href' => 'http://localhost/api/v1/posts?' . Arr::query([
+                        'page' => ['limit' => '3'],
+                        'sort' => 'title',
+                    ]),
+            ],
+            'next' => [
+                'href' => 'http://localhost/api/v1/posts?' . Arr::query([
+                        'page' => [
+                            'after' => $this->encodeCursor(
+                                ["posts.title"=> "c"],
+                                pointsToNextItems: true,
+                            ),
+                            'limit' => '3',
+                        ],
+                        'sort' => 'title',
+                    ]),
+            ],
+        ];
+
+        $page = $this->posts->repository()->queryAll()->sort('title')->paginate(['limit' => '3']);
+
+        $this->assertSame(['page' => $meta], $page->meta());
+        $this->assertSame($links, $page->links()->toArray());
+        $this->assertPage($posts->reverse()->take(3), $page);
+    }
+
     /**
      * @return void
      */