diff --git a/hapi/datasets/folder.py b/hapi/datasets/folder.py
index 1d8c2a3e54403710b2c054e9fbf23af989eb1a52..c0b7c08794c4ca00301e5aee623f5d44db251bf1 100644
--- a/hapi/datasets/folder.py
+++ b/hapi/datasets/folder.py
@@ -34,13 +34,10 @@ def has_valid_extension(filename, extensions):
     return filename.lower().endswith(extensions)
 
 
-def make_dataset(dir, class_to_idx, extensions=None, is_valid_file=None):
+def make_dataset(dir, class_to_idx, extensions, is_valid_file=None):
     images = []
     dir = os.path.expanduser(dir)
-    if not ((extensions is None) ^ (is_valid_file is None)):
-        raise ValueError(
-            "Both extensions and is_valid_file cannot be None or not None at the same time"
-        )
+
     if extensions is not None:
 
         def is_valid_file(x):
@@ -200,10 +197,7 @@ class ImageFolder(Dataset):
 
         samples = []
         path = os.path.expanduser(root)
-        if not ((extensions is None) ^ (is_valid_file is None)):
-            raise ValueError(
-                "Both extensions and is_valid_file cannot be None or not None at the same time"
-            )
+
         if extensions is not None:
 
             def is_valid_file(x):
diff --git a/hapi/datasets/utils.py b/hapi/datasets/utils.py
index b580dd235739fe2d096a38fed16c8ef4af427ca1..171f794ba9df4270727a23cc6cd039a9faa81970 100644
--- a/hapi/datasets/utils.py
+++ b/hapi/datasets/utils.py
@@ -25,5 +25,5 @@ def _check_exists_and_download(path, url, md5, module_name, download=True):
     if download:
         return paddle.dataset.common.download(url, module_name, md5)
     else:
-        raise FileNotFoundError(
-            '{} not exists and auto download disabled'.format(path))
+        raise ValueError('{} not exists and auto download disabled'.format(
+            path))
diff --git a/hapi/tests/test_datasets.py b/hapi/tests/test_datasets.py
index 857d037eb1195cfa4b8b835e7c1e63be5bd63d37..cec6f1e748de65508e73fa4464aaac6b9f2acba7 100644
--- a/hapi/tests/test_datasets.py
+++ b/hapi/tests/test_datasets.py
@@ -20,11 +20,14 @@ import shutil
 import cv2
 
 from hapi.datasets import *
+from hapi.datasets.utils import _check_exists_and_download
+from hapi.vision.transforms import Compose
 
 
 class TestFolderDatasets(unittest.TestCase):
-    def makedata(self):
+    def setUp(self):
         self.data_dir = tempfile.mkdtemp()
+        self.empty_dir = tempfile.mkdtemp()
         for i in range(2):
             sub_dir = os.path.join(self.data_dir, 'class_' + str(i))
             if not os.path.exists(sub_dir):
@@ -34,8 +37,10 @@ class TestFolderDatasets(unittest.TestCase):
                     (32, 32, 3)) * 255).astype('uint8')
                 cv2.imwrite(os.path.join(sub_dir, str(j) + '.jpg'), fake_img)
 
+    def tearDown(self):
+        shutil.rmtree(self.data_dir)
+
     def test_dataset(self):
-        self.makedata()
         dataset_folder = DatasetFolder(self.data_dir)
 
         for _ in dataset_folder:
@@ -44,7 +49,30 @@ class TestFolderDatasets(unittest.TestCase):
         assert len(dataset_folder) == 4
         assert len(dataset_folder.classes) == 2
 
-        shutil.rmtree(self.data_dir)
+        transform = Compose([])
+        dataset_folder = DatasetFolder(self.data_dir, transform=transform)
+        for _ in dataset_folder:
+            pass
+
+    def test_folder(self):
+        loader = ImageFolder(self.data_dir)
+
+        for _ in loader:
+            pass
+
+        transform = Compose([])
+        loader = ImageFolder(self.data_dir, transform=transform)
+        for _ in loader:
+            pass
+
+    def test_errors(self):
+        with self.assertRaises(RuntimeError):
+            ImageFolder(self.empty_dir)
+        with self.assertRaises(RuntimeError):
+            DatasetFolder(self.empty_dir)
+
+        with self.assertRaises(ValueError):
+            _check_exists_and_download('temp_paddle', None, None, None, False)
 
 
 class TestMNISTTest(unittest.TestCase):