Compare item ids in tests

Signed-off-by: Ilya Trushkin <ilya.trushkin@intel.com>

tests/unit/test_dataset.py

@@ -2049,23 +2049,28 @@ def test_index_access_tile(self):
         dataset = Dataset.from_iterable(
             DatasetItem(
                 id,
-                media=Image.from_numpy(data=np.ones((10, 6, 3))),
+                media=Image.from_numpy(data=np.ones((224, 224, 3))),
                 annotations=[
                     Bbox(1, 2, 3, 4, label=1),
                 ],
             )
             for id in range(5)
         )
         length = len(dataset)
-        n_rows, n_cols = (1, 2)
+        n_rows, n_cols = (4, 4)
         dataset.transform("tile", grid_size=(n_rows, n_cols), overlap=(0, 0), threshold_drop_ann=0)
         tiled_length = length * n_rows * n_cols
-        for i in range(tiled_length):
-            dataset[i]
+        for i in range(length):
+            for row in range(n_rows):
+                for col in range(n_cols):
+                    idx = i * n_rows * n_cols + row * n_cols + col
+                    _id = f"{i}_tile_{row * n_cols + col}"
+                    self.assertEqual(dataset[idx].id, _id)
         self.assertRaises(IndexError, lambda: dataset[tiled_length])
+
         dataset.transform("merge_tile")
         for i in range(length):
-            dataset[i]
+            self.assertEqual(dataset[i].id, str(i))
         self.assertRaises(IndexError, lambda: dataset[length])