[util] support integer values for '…-range' options (#8604)

gallery_dl/util.py

@@ -1011,6 +1011,8 @@ class RangePredicate():
 
         if isinstance(rangespec, str):
             rangespec = rangespec.split(",")
+        elif isinstance(rangespec, int):
+            rangespec = (str(rangespec),)
 
         for group in rangespec:
             if not group:

test/test_util.py

@@ -40,6 +40,7 @@ class TestRange(unittest.TestCase):
     def test_parse_digit(self):
         f = self.predicate._parse
 
+        self.assertEqual(f(2), [range(2, 3)])
         self.assertEqual(f("2"), [range(2, 3)])
 
         self.assertEqual(
@@ -48,6 +49,12 @@ class TestRange(unittest.TestCase):
              range(3, 4),
              range(4, 5)],
         )
+        self.assertEqual(
+            f(["2", "3", "4"]),
+            [range(2, 3),
+             range(3, 4),
+             range(4, 5)],
+        )
 
     def test_parse_range(self):
         f = self.predicate._parse