Fix bug in tests and in food101 dataset

Author: jdsgomes

test/test_datasets.py

@@ -2194,11 +2194,13 @@ def inject_fake_data(self, tmpdir: str, config):
                 file_name_fn=lambda idx: f"{idx}.jpg",
                 num_examples=num_images_per_class,
             )
-            metadata[cls] = [str(fname) for fname in random.choices(im_fnames, k=n_samples_per_class)]
+            metadata[cls] = [
+                fname.parent.name + "/" + fname.name for fname in random.choices(im_fnames, k=n_samples_per_class)
+            ]
 
         with open(meta_folder / f"{config['split']}.json", "w") as file:
             file.write(json.dumps(metadata))
-
+        print(metadata)
         return len(sampled_classes * n_samples_per_class)
 
 

torchvision/datasets/food101.py

@@ -58,9 +58,11 @@ def __init__(
         self.classes = sorted(metadata.keys())
         self.class_to_idx = dict(zip(self.classes, range(len(self.classes))))
 
-        for class_label, im_ids in metadata.items():
-            self._labels += [self.class_to_idx[class_label]] * len(im_ids)
-            self._image_files += [self._images_folder.joinpath(*f"{im_id}.jpg".split("/")) for im_id in im_ids]
+        for class_label, im_rel_paths in metadata.items():
+            self._labels += [self.class_to_idx[class_label]] * len(im_rel_paths)
+            self._image_files += [
+                self._images_folder.joinpath(*f"{im_rel_path}".split("/")) for im_rel_path in im_rel_paths
+            ]
 
     def __len__(self) -> int:
         return len(self._image_files)