diff --git a/test/test_extractor.py b/test/test_extractor.py
index 2555b585..e163b936 100644
--- a/test/test_extractor.py
+++ b/test/test_extractor.py
@@ -1,15 +1,19 @@
 #!/usr/bin/env python3
 # -*- coding: utf-8 -*-
 
-# Copyright 2018-2019 Mike Fährmann
+# Copyright 2018-2020 Mike Fährmann
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License version 2 as
 # published by the Free Software Foundation.
 
 import sys
-import unittest
+import time
 import string
+from datetime import datetime, timedelta
+
+import unittest
+from unittest.mock import patch
 
 from gallery_dl import extractor
 from gallery_dl.extractor.common import Extractor, Message
@@ -26,7 +30,7 @@ class FakeExtractor(Extractor):
         yield Message.Url, "text:foobar", {}
 
 
-class TestExtractor(unittest.TestCase):
+class TestExtractorModule(unittest.TestCase):
     VALID_URIS = (
         "https://example.org/file.jpg",
         "tumblr:foobar",
@@ -170,5 +174,65 @@ class TestExtractor(unittest.TestCase):
                 self.assertEqual(expected, extr.__name__)
 
 
+class TestExtractorWait(unittest.TestCase):
+
+    def test_wait_seconds(self):
+        extr = extractor.find("test:")
+        seconds = 5
+        until = time.time() + seconds
+
+        with patch("time.sleep") as sleep, patch.object(extr, "log") as log:
+            extr.wait(seconds=seconds)
+
+            sleep.assert_called_once_with(6.0)
+
+            calls = log.info.mock_calls
+            self.assertEqual(len(calls), 1)
+            self._assert_isotime(calls[0][1][1], until)
+
+    def test_wait_until(self):
+        extr = extractor.find("test:")
+        until = time.time() + 5
+
+        with patch("time.sleep") as sleep, patch.object(extr, "log") as log:
+            extr.wait(until=until)
+
+            calls = sleep.mock_calls
+            self.assertEqual(len(calls), 1)
+            self.assertAlmostEqual(calls[0][1][0], 6.0, places=1)
+
+            calls = log.info.mock_calls
+            self.assertEqual(len(calls), 1)
+            self._assert_isotime(calls[0][1][1], until)
+
+    def test_wait_until_datetime(self):
+        extr = extractor.find("test:")
+        until = datetime.utcnow() + timedelta(seconds=5)
+        until_local = datetime.now() + timedelta(seconds=5)
+
+        with patch("time.sleep") as sleep, patch.object(extr, "log") as log:
+            extr.wait(until=until)
+
+            calls = sleep.mock_calls
+            self.assertEqual(len(calls), 1)
+            self.assertAlmostEqual(calls[0][1][0], 6.0, places=1)
+
+            calls = log.info.mock_calls
+            self.assertEqual(len(calls), 1)
+            self._assert_isotime(calls[0][1][1], until_local)
+
+    def _assert_isotime(self, output, until):
+        if not isinstance(until, datetime):
+            until = datetime.fromtimestamp(until)
+        o = self._isotime_to_seconds(output)
+        u = self._isotime_to_seconds(until.time().isoformat()[:8])
+        self.assertLess(o-u, 1.0)
+
+    @staticmethod
+    def _isotime_to_seconds(isotime):
+        parts = isotime.split(":")
+        return int(parts[0]) * 3600 + int(parts[1]) * 60 + int(parts[2])
+
+
 if __name__ == "__main__":
     unittest.main()