test/test_InfoExtractor.py

@@ -153,9 +153,6 @@ class TestInfoExtractor(unittest.TestCase):
 '''
         search = self.ie._search_nextjs_data(html, 'testID')
         self.assertEqual(search['props']['pageProps']['video']['id'], 'testid')
-        search = self.ie._search_nextjs_data(
-            'no next.js data here, move along', 'testID', default={'status': 0})
-        self.assertEqual(search['status'], 0)
 
     def test_search_nuxt_data(self):
         html = '''

test/test_traversal.py

@@ -1,509 +0,0 @@
-#!/usr/bin/env python
-# coding: utf-8
-from __future__ import unicode_literals
-
-# Allow direct execution
-import os
-import sys
-import unittest
-sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
-
-
-import re
-
-from youtube_dl.traversal import (
-    dict_get,
-    get_first,
-    T,
-    traverse_obj,
-)
-from youtube_dl.compat import (
-    compat_etree_fromstring,
-    compat_http_cookies,
-    compat_str,
-)
-from youtube_dl.utils import (
-    int_or_none,
-    str_or_none,
-)
-
-_TEST_DATA = {
-    100: 100,
-    1.2: 1.2,
-    'str': 'str',
-    'None': None,
-    '...': Ellipsis,
-    'urls': [
-        {'index': 0, 'url': 'https://www.example.com/0'},
-        {'index': 1, 'url': 'https://www.example.com/1'},
-    ],
-    'data': (
-        {'index': 2},
-        {'index': 3},
-    ),
-    'dict': {},
-}
-
-
-if sys.version_info < (3, 0):
-    class _TestCase(unittest.TestCase):
-
-        def assertCountEqual(self, *args, **kwargs):
-            return self.assertItemsEqual(*args, **kwargs)
-else:
-    _TestCase = unittest.TestCase
-
-
-class TestTraversal(_TestCase):
-    def assertMaybeCountEqual(self, *args, **kwargs):
-        if sys.version_info < (3, 7):
-            # random dict order
-            return self.assertCountEqual(*args, **kwargs)
-        else:
-            return self.assertEqual(*args, **kwargs)
-
-    def test_traverse_obj(self):
-        # instant compat
-        str = compat_str
-
-        # define a pukka Iterable
-        def iter_range(stop):
-            for from_ in range(stop):
-                yield from_
-
-        # Test base functionality
-        self.assertEqual(traverse_obj(_TEST_DATA, ('str',)), 'str',
-                         msg='allow tuple path')
-        self.assertEqual(traverse_obj(_TEST_DATA, ['str']), 'str',
-                         msg='allow list path')
-        self.assertEqual(traverse_obj(_TEST_DATA, (value for value in ("str",))), 'str',
-                         msg='allow iterable path')
-        self.assertEqual(traverse_obj(_TEST_DATA, 'str'), 'str',
-                         msg='single items should be treated as a path')
-        self.assertEqual(traverse_obj(_TEST_DATA, None), _TEST_DATA)
-        self.assertEqual(traverse_obj(_TEST_DATA, 100), 100)
-        self.assertEqual(traverse_obj(_TEST_DATA, 1.2), 1.2)
-
-        # Test Ellipsis behavior
-        self.assertCountEqual(traverse_obj(_TEST_DATA, Ellipsis),
-                              (item for item in _TEST_DATA.values() if item not in (None, {})),
-                              msg='`...` should give all non-discarded values')
-        self.assertCountEqual(traverse_obj(_TEST_DATA, ('urls', 0, Ellipsis)), _TEST_DATA['urls'][0].values(),
-                              msg='`...` selection for dicts should select all values')
-        self.assertEqual(traverse_obj(_TEST_DATA, (Ellipsis, Ellipsis, 'url')),
-                         ['https://www.example.com/0', 'https://www.example.com/1'],
-                         msg='nested `...` queries should work')
-        self.assertCountEqual(traverse_obj(_TEST_DATA, (Ellipsis, Ellipsis, 'index')), iter_range(4),
-                              msg='`...` query result should be flattened')
-        self.assertEqual(traverse_obj(iter(range(4)), Ellipsis), list(range(4)),
-                         msg='`...` should accept iterables')
-
-        # Test function as key
-        self.assertEqual(traverse_obj(_TEST_DATA, lambda x, y: x == 'urls' and isinstance(y, list)),
-                         [_TEST_DATA['urls']],
-                         msg='function as query key should perform a filter based on (key, value)')
-        self.assertCountEqual(traverse_obj(_TEST_DATA, lambda _, x: isinstance(x[0], str)), set(('str',)),
-                              msg='exceptions in the query function should be caught')
-        self.assertEqual(traverse_obj(iter(range(4)), lambda _, x: x % 2 == 0), [0, 2],
-                         msg='function key should accept iterables')
-        if __debug__:
-            with self.assertRaises(Exception, msg='Wrong function signature should raise in debug'):
-                traverse_obj(_TEST_DATA, lambda a: Ellipsis)
-            with self.assertRaises(Exception, msg='Wrong function signature should raise in debug'):
-                traverse_obj(_TEST_DATA, lambda a, b, c: Ellipsis)
-
-        # Test set as key (transformation/type, like `expected_type`)
-        self.assertEqual(traverse_obj(_TEST_DATA, (Ellipsis, T(str.upper), )), ['STR'],
-                         msg='Function in set should be a transformation')
-        self.assertEqual(traverse_obj(_TEST_DATA, ('fail', T(lambda _: 'const'))), 'const',
-                         msg='Function in set should always be called')
-        self.assertEqual(traverse_obj(_TEST_DATA, (Ellipsis, T(str))), ['str'],
-                         msg='Type in set should be a type filter')
-        self.assertMaybeCountEqual(traverse_obj(_TEST_DATA, (Ellipsis, T(str, int))), [100, 'str'],
-                                   msg='Multiple types in set should be a type filter')
-        self.assertEqual(traverse_obj(_TEST_DATA, T(dict)), _TEST_DATA,
-                         msg='A single set should be wrapped into a path')
-        self.assertEqual(traverse_obj(_TEST_DATA, (Ellipsis, T(str.upper))), ['STR'],
-                         msg='Transformation function should not raise')
-        self.assertMaybeCountEqual(traverse_obj(_TEST_DATA, (Ellipsis, T(str_or_none))),
-                                   [item for item in map(str_or_none, _TEST_DATA.values()) if item is not None],
-                                   msg='Function in set should be a transformation')
-        if __debug__:
-            with self.assertRaises(Exception, msg='Sets with length != 1 should raise in debug'):
-                traverse_obj(_TEST_DATA, set())
-            with self.assertRaises(Exception, msg='Sets with length != 1 should raise in debug'):
-                traverse_obj(_TEST_DATA, set((str.upper, str)))
-
-        # Test `slice` as a key
-        _SLICE_DATA = [0, 1, 2, 3, 4]
-        self.assertEqual(traverse_obj(_TEST_DATA, ('dict', slice(1))), None,
-                         msg='slice on a dictionary should not throw')
-        self.assertEqual(traverse_obj(_SLICE_DATA, slice(1)), _SLICE_DATA[:1],
-                         msg='slice key should apply slice to sequence')
-        self.assertEqual(traverse_obj(_SLICE_DATA, slice(1, 2)), _SLICE_DATA[1:2],
-                         msg='slice key should apply slice to sequence')
-        self.assertEqual(traverse_obj(_SLICE_DATA, slice(1, 4, 2)), _SLICE_DATA[1:4:2],
-                         msg='slice key should apply slice to sequence')
-
-        # Test alternative paths
-        self.assertEqual(traverse_obj(_TEST_DATA, 'fail', 'str'), 'str',
-                         msg='multiple `paths` should be treated as alternative paths')
-        self.assertEqual(traverse_obj(_TEST_DATA, 'str', 100), 'str',
-                         msg='alternatives should exit early')
-        self.assertEqual(traverse_obj(_TEST_DATA, 'fail', 'fail'), None,
-                         msg='alternatives should return `default` if exhausted')
-        self.assertEqual(traverse_obj(_TEST_DATA, (Ellipsis, 'fail'), 100), 100,
-                         msg='alternatives should track their own branching return')
-        self.assertEqual(traverse_obj(_TEST_DATA, ('dict', Ellipsis), ('data', Ellipsis)), list(_TEST_DATA['data']),
-                         msg='alternatives on empty objects should search further')
-
-        # Test branch and path nesting
-        self.assertEqual(traverse_obj(_TEST_DATA, ('urls', (3, 0), 'url')), ['https://www.example.com/0'],
-                         msg='tuple as key should be treated as branches')
-        self.assertEqual(traverse_obj(_TEST_DATA, ('urls', [3, 0], 'url')), ['https://www.example.com/0'],
-                         msg='list as key should be treated as branches')
-        self.assertEqual(traverse_obj(_TEST_DATA, ('urls', ((1, 'fail'), (0, 'url')))), ['https://www.example.com/0'],
-                         msg='double nesting in path should be treated as paths')
-        self.assertEqual(traverse_obj(['0', [1, 2]], [(0, 1), 0]), [1],
-                         msg='do not fail early on branching')
-        self.assertCountEqual(traverse_obj(_TEST_DATA, ('urls', ((1, ('fail', 'url')), (0, 'url')))),
-                              ['https://www.example.com/0', 'https://www.example.com/1'],
-                              msg='triple nesting in path should be treated as branches')
-        self.assertEqual(traverse_obj(_TEST_DATA, ('urls', ('fail', (Ellipsis, 'url')))),
-                         ['https://www.example.com/0', 'https://www.example.com/1'],
-                         msg='ellipsis as branch path start gets flattened')
-
-        # Test dictionary as key
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: 100, 1: 1.2}), {0: 100, 1: 1.2},
-                         msg='dict key should result in a dict with the same keys')
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: ('urls', 0, 'url')}),
-                         {0: 'https://www.example.com/0'},
-                         msg='dict key should allow paths')
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: ('urls', (3, 0), 'url')}),
-                         {0: ['https://www.example.com/0']},
-                         msg='tuple in dict path should be treated as branches')
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: ('urls', ((1, 'fail'), (0, 'url')))}),
-                         {0: ['https://www.example.com/0']},
-                         msg='double nesting in dict path should be treated as paths')
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: ('urls', ((1, ('fail', 'url')), (0, 'url')))}),
-                         {0: ['https://www.example.com/1', 'https://www.example.com/0']},
-                         msg='triple nesting in dict path should be treated as branches')
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: 'fail'}), {},
-                         msg='remove `None` values when top level dict key fails')
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: 'fail'}, default=Ellipsis), {0: Ellipsis},
-                         msg='use `default` if key fails and `default`')
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: 'dict'}), {},
-                         msg='remove empty values when dict key')
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: 'dict'}, default=Ellipsis), {0: Ellipsis},
-                         msg='use `default` when dict key and a default')
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: {0: 'fail'}}), {},
-                         msg='remove empty values when nested dict key fails')
-        self.assertEqual(traverse_obj(None, {0: 'fail'}), {},
-                         msg='default to dict if pruned')
-        self.assertEqual(traverse_obj(None, {0: 'fail'}, default=Ellipsis), {0: Ellipsis},
-                         msg='default to dict if pruned and default is given')
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: {0: 'fail'}}, default=Ellipsis), {0: {0: Ellipsis}},
-                         msg='use nested `default` when nested dict key fails and `default`')
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: ('dict', Ellipsis)}), {},
-                         msg='remove key if branch in dict key not successful')
-
-        # Testing default parameter behavior
-        _DEFAULT_DATA = {'None': None, 'int': 0, 'list': []}
-        self.assertEqual(traverse_obj(_DEFAULT_DATA, 'fail'), None,
-                         msg='default value should be `None`')
-        self.assertEqual(traverse_obj(_DEFAULT_DATA, 'fail', 'fail', default=Ellipsis), Ellipsis,
-                         msg='chained fails should result in default')
-        self.assertEqual(traverse_obj(_DEFAULT_DATA, 'None', 'int'), 0,
-                         msg='should not short cirquit on `None`')
-        self.assertEqual(traverse_obj(_DEFAULT_DATA, 'fail', default=1), 1,
-                         msg='invalid dict key should result in `default`')
-        self.assertEqual(traverse_obj(_DEFAULT_DATA, 'None', default=1), 1,
-                         msg='`None` is a deliberate sentinel and should become `default`')
-        self.assertEqual(traverse_obj(_DEFAULT_DATA, ('list', 10)), None,
-                         msg='`IndexError` should result in `default`')
-        self.assertEqual(traverse_obj(_DEFAULT_DATA, (Ellipsis, 'fail'), default=1), 1,
-                         msg='if branched but not successful return `default` if defined, not `[]`')
-        self.assertEqual(traverse_obj(_DEFAULT_DATA, (Ellipsis, 'fail'), default=None), None,
-                         msg='if branched but not successful return `default` even if `default` is `None`')
-        self.assertEqual(traverse_obj(_DEFAULT_DATA, (Ellipsis, 'fail')), [],
-                         msg='if branched but not successful return `[]`, not `default`')
-        self.assertEqual(traverse_obj(_DEFAULT_DATA, ('list', Ellipsis)), [],
-                         msg='if branched but object is empty return `[]`, not `default`')
-        self.assertEqual(traverse_obj(None, Ellipsis), [],
-                         msg='if branched but object is `None` return `[]`, not `default`')
-        self.assertEqual(traverse_obj({0: None}, (0, Ellipsis)), [],
-                         msg='if branched but state is `None` return `[]`, not `default`')
-
-        branching_paths = [
-            ('fail', Ellipsis),
-            (Ellipsis, 'fail'),
-            100 * ('fail',) + (Ellipsis,),
-            (Ellipsis,) + 100 * ('fail',),
-        ]
-        for branching_path in branching_paths:
-            self.assertEqual(traverse_obj({}, branching_path), [],
-                             msg='if branched but state is `None`, return `[]` (not `default`)')
-            self.assertEqual(traverse_obj({}, 'fail', branching_path), [],
-                             msg='if branching in last alternative and previous did not match, return `[]` (not `default`)')
-            self.assertEqual(traverse_obj({0: 'x'}, 0, branching_path), 'x',
-                             msg='if branching in last alternative and previous did match, return single value')
-            self.assertEqual(traverse_obj({0: 'x'}, branching_path, 0), 'x',
-                             msg='if branching in first alternative and non-branching path does match, return single value')
-            self.assertEqual(traverse_obj({}, branching_path, 'fail'), None,
-                             msg='if branching in first alternative and non-branching path does not match, return `default`')
-
-        # Testing expected_type behavior
-        _EXPECTED_TYPE_DATA = {'str': 'str', 'int': 0}
-        self.assertEqual(traverse_obj(_EXPECTED_TYPE_DATA, 'str', expected_type=str),
-                         'str', msg='accept matching `expected_type` type')
-        self.assertEqual(traverse_obj(_EXPECTED_TYPE_DATA, 'str', expected_type=int),
-                         None, msg='reject non-matching `expected_type` type')
-        self.assertEqual(traverse_obj(_EXPECTED_TYPE_DATA, 'int', expected_type=lambda x: str(x)),
-                         '0', msg='transform type using type function')
-        self.assertEqual(traverse_obj(_EXPECTED_TYPE_DATA, 'str', expected_type=lambda _: 1 / 0),
-                         None, msg='wrap expected_type function in try_call')
-        self.assertEqual(traverse_obj(_EXPECTED_TYPE_DATA, Ellipsis, expected_type=str),
-                         ['str'], msg='eliminate items that expected_type fails on')
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: 100, 1: 1.2}, expected_type=int),
-                         {0: 100}, msg='type as expected_type should filter dict values')
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: 100, 1: 1.2, 2: 'None'}, expected_type=str_or_none),
-                         {0: '100', 1: '1.2'}, msg='function as expected_type should transform dict values')
-        self.assertEqual(traverse_obj(_TEST_DATA, ({0: 1.2}, 0, set((int_or_none,))), expected_type=int),
-                         1, msg='expected_type should not filter non-final dict values')
-        self.assertEqual(traverse_obj(_TEST_DATA, {0: {0: 100, 1: 'str'}}, expected_type=int),
-                         {0: {0: 100}}, msg='expected_type should transform deep dict values')
-        self.assertEqual(traverse_obj(_TEST_DATA, [({0: '...'}, {0: '...'})], expected_type=type(Ellipsis)),
-                         [{0: Ellipsis}, {0: Ellipsis}], msg='expected_type should transform branched dict values')
-        self.assertEqual(traverse_obj({1: {3: 4}}, [(1, 2), 3], expected_type=int),
-                         [4], msg='expected_type regression for type matching in tuple branching')
-        self.assertEqual(traverse_obj(_TEST_DATA, ['data', Ellipsis], expected_type=int),
-                         [], msg='expected_type regression for type matching in dict result')
-
-        # Test get_all behavior
-        _GET_ALL_DATA = {'key': [0, 1, 2]}
-        self.assertEqual(traverse_obj(_GET_ALL_DATA, ('key', Ellipsis), get_all=False), 0,
-                         msg='if not `get_all`, return only first matching value')
-        self.assertEqual(traverse_obj(_GET_ALL_DATA, Ellipsis, get_all=False), [0, 1, 2],
-                         msg='do not overflatten if not `get_all`')
-
-        # Test casesense behavior
-        _CASESENSE_DATA = {
-            'KeY': 'value0',
-            0: {
-                'KeY': 'value1',
-                0: {'KeY': 'value2'},
-            },
-            # FULLWIDTH LATIN CAPITAL LETTER K
-            '\uff2bey': 'value3',
-        }
-        self.assertEqual(traverse_obj(_CASESENSE_DATA, 'key'), None,
-                         msg='dict keys should be case sensitive unless `casesense`')
-        self.assertEqual(traverse_obj(_CASESENSE_DATA, 'keY',
-                                      casesense=False), 'value0',
-                         msg='allow non matching key case if `casesense`')
-        self.assertEqual(traverse_obj(_CASESENSE_DATA, '\uff4bey',  # FULLWIDTH LATIN SMALL LETTER K
-                                      casesense=False), 'value3',
-                         msg='allow non matching Unicode key case if `casesense`')
-        self.assertEqual(traverse_obj(_CASESENSE_DATA, (0, ('keY',)),
-                                      casesense=False), ['value1'],
-                         msg='allow non matching key case in branch if `casesense`')
-        self.assertEqual(traverse_obj(_CASESENSE_DATA, (0, ((0, 'keY'),)),
-                                      casesense=False), ['value2'],
-                         msg='allow non matching key case in branch path if `casesense`')
-
-        # Test traverse_string behavior
-        _TRAVERSE_STRING_DATA = {'str': 'str', 1.2: 1.2}
-        self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, ('str', 0)), None,
-                         msg='do not traverse into string if not `traverse_string`')
-        self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, ('str', 0),
-                                      _traverse_string=True), 's',
-                         msg='traverse into string if `traverse_string`')
-        self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, (1.2, 1),
-                                      _traverse_string=True), '.',
-                         msg='traverse into converted data if `traverse_string`')
-        self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, ('str', Ellipsis),
-                                      _traverse_string=True), 'str',
-                         msg='`...` should result in string (same value) if `traverse_string`')
-        self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, ('str', slice(0, None, 2)),
-                                      _traverse_string=True), 'sr',
-                         msg='`slice` should result in string if `traverse_string`')
-        self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, ('str', lambda i, v: i or v == 's'),
-                                      _traverse_string=True), 'str',
-                         msg='function should result in string if `traverse_string`')
-        self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, ('str', (0, 2)),
-                                      _traverse_string=True), ['s', 'r'],
-                         msg='branching should result in list if `traverse_string`')
-        self.assertEqual(traverse_obj({}, (0, Ellipsis), _traverse_string=True), [],
-                         msg='branching should result in list if `traverse_string`')
-        self.assertEqual(traverse_obj({}, (0, lambda x, y: True), _traverse_string=True), [],
-                         msg='branching should result in list if `traverse_string`')
-        self.assertEqual(traverse_obj({}, (0, slice(1)), _traverse_string=True), [],
-                         msg='branching should result in list if `traverse_string`')
-
-        # Test re.Match as input obj
-        mobj = re.match(r'^0(12)(?P<group>3)(4)?$', '0123')
-        self.assertEqual(traverse_obj(mobj, Ellipsis), [x for x in mobj.groups() if x is not None],
-                         msg='`...` on a `re.Match` should give its `groups()`')
-        self.assertEqual(traverse_obj(mobj, lambda k, _: k in (0, 2)), ['0123', '3'],
-                         msg='function on a `re.Match` should give groupno, value starting at 0')
-        self.assertEqual(traverse_obj(mobj, 'group'), '3',
-                         msg='str key on a `re.Match` should give group with that name')
-        self.assertEqual(traverse_obj(mobj, 2), '3',
-                         msg='int key on a `re.Match` should give group with that name')
-        self.assertEqual(traverse_obj(mobj, 'gRoUp', casesense=False), '3',
-                         msg='str key on a `re.Match` should respect casesense')
-        self.assertEqual(traverse_obj(mobj, 'fail'), None,
-                         msg='failing str key on a `re.Match` should return `default`')
-        self.assertEqual(traverse_obj(mobj, 'gRoUpS', casesense=False), None,
-                         msg='failing str key on a `re.Match` should return `default`')
-        self.assertEqual(traverse_obj(mobj, 8), None,
-                         msg='failing int key on a `re.Match` should return `default`')
-        self.assertEqual(traverse_obj(mobj, lambda k, _: k in (0, 'group')), ['0123', '3'],
-                         msg='function on a `re.Match` should give group name as well')
-
-        # Test xml.etree.ElementTree.Element as input obj
-        etree = compat_etree_fromstring('''<?xml version="1.0"?>
-        <data>
-            <country name="Liechtenstein">
-                <rank>1</rank>
-                <year>2008</year>
-                <gdppc>141100</gdppc>
-                <neighbor name="Austria" direction="E"/>
-                <neighbor name="Switzerland" direction="W"/>
-            </country>
-            <country name="Singapore">
-                <rank>4</rank>
-                <year>2011</year>
-                <gdppc>59900</gdppc>
-                <neighbor name="Malaysia" direction="N"/>
-            </country>
-            <country name="Panama">
-                <rank>68</rank>
-                <year>2011</year>
-                <gdppc>13600</gdppc>
-                <neighbor name="Costa Rica" direction="W"/>
-                <neighbor name="Colombia" direction="E"/>
-            </country>
-        </data>''')
-        self.assertEqual(traverse_obj(etree, ''), etree,
-                         msg='empty str key should return the element itself')
-        self.assertEqual(traverse_obj(etree, 'country'), list(etree),
-                         msg='str key should return all children with that tag name')
-        self.assertEqual(traverse_obj(etree, Ellipsis), list(etree),
-                         msg='`...` as key should return all children')
-        self.assertEqual(traverse_obj(etree, lambda _, x: x[0].text == '4'), [etree[1]],
-                         msg='function as key should get element as value')
-        self.assertEqual(traverse_obj(etree, lambda i, _: i == 1), [etree[1]],
-                         msg='function as key should get index as key')
-        self.assertEqual(traverse_obj(etree, 0), etree[0],
-                         msg='int key should return the nth child')
-        self.assertEqual(traverse_obj(etree, './/neighbor/@name'),
-                         ['Austria', 'Switzerland', 'Malaysia', 'Costa Rica', 'Colombia'],
-                         msg='`@<attribute>` at end of path should give that attribute')
-        self.assertEqual(traverse_obj(etree, '//neighbor/@fail'), [None, None, None, None, None],
-                         msg='`@<nonexistent>` at end of path should give `None`')
-        self.assertEqual(traverse_obj(etree, ('//neighbor/@', 2)), {'name': 'Malaysia', 'direction': 'N'},
-                         msg='`@` should give the full attribute dict')
-        self.assertEqual(traverse_obj(etree, '//year/text()'), ['2008', '2011', '2011'],
-                         msg='`text()` at end of path should give the inner text')
-        self.assertEqual(traverse_obj(etree, '//*[@direction]/@direction'), ['E', 'W', 'N', 'W', 'E'],
-                         msg='full python xpath features should be supported')
-        self.assertEqual(traverse_obj(etree, (0, '@name')), 'Liechtenstein',
-                         msg='special transformations should act on current element')
-        self.assertEqual(traverse_obj(etree, ('country', 0, Ellipsis, 'text()', T(int_or_none))), [1, 2008, 141100],
-                         msg='special transformations should act on current element')
-
-    def test_traversal_unbranching(self):
-        self.assertEqual(traverse_obj(_TEST_DATA, [(100, 1.2), all]), [100, 1.2],
-                         msg='`all` should give all results as list')
-        self.assertEqual(traverse_obj(_TEST_DATA, [(100, 1.2), any]), 100,
-                         msg='`any` should give the first result')
-        self.assertEqual(traverse_obj(_TEST_DATA, [100, all]), [100],
-                         msg='`all` should give list if non branching')
-        self.assertEqual(traverse_obj(_TEST_DATA, [100, any]), 100,
-                         msg='`any` should give single item if non branching')
-        self.assertEqual(traverse_obj(_TEST_DATA, [('dict', 'None', 100), all]), [100],
-                         msg='`all` should filter `None` and empty dict')
-        self.assertEqual(traverse_obj(_TEST_DATA, [('dict', 'None', 100), any]), 100,
-                         msg='`any` should filter `None` and empty dict')
-        self.assertEqual(traverse_obj(_TEST_DATA, [{
-            'all': [('dict', 'None', 100, 1.2), all],
-            'any': [('dict', 'None', 100, 1.2), any],
-        }]), {'all': [100, 1.2], 'any': 100},
-            msg='`all`/`any` should apply to each dict path separately')
-        self.assertEqual(traverse_obj(_TEST_DATA, [{
-            'all': [('dict', 'None', 100, 1.2), all],
-            'any': [('dict', 'None', 100, 1.2), any],
-        }], get_all=False), {'all': [100, 1.2], 'any': 100},
-            msg='`all`/`any` should apply to dict regardless of `get_all`')
-        self.assertIs(traverse_obj(_TEST_DATA, [('dict', 'None', 100, 1.2), all, T(float)]), None,
-                      msg='`all` should reset branching status')
-        self.assertIs(traverse_obj(_TEST_DATA, [('dict', 'None', 100, 1.2), any, T(float)]), None,
-                      msg='`any` should reset branching status')
-        self.assertEqual(traverse_obj(_TEST_DATA, [('dict', 'None', 100, 1.2), all, Ellipsis, T(float)]), [1.2],
-                         msg='`all` should allow further branching')
-        self.assertEqual(traverse_obj(_TEST_DATA, [('dict', 'None', 'urls', 'data'), any, Ellipsis, 'index']), [0, 1],
-                         msg='`any` should allow further branching')
-
-    def test_traversal_morsel(self):
-        values = {
-            'expires': 'a',
-            'path': 'b',
-            'comment': 'c',
-            'domain': 'd',
-            'max-age': 'e',
-            'secure': 'f',
-            'httponly': 'g',
-            'version': 'h',
-            'samesite': 'i',
-        }
-        # SameSite added in Py3.8, breaks .update for 3.5-3.7
-        if sys.version_info < (3, 8):
-            del values['samesite']
-        morsel = compat_http_cookies.Morsel()
-        morsel.set(str('item_key'), 'item_value', 'coded_value')
-        morsel.update(values)
-        values['key'] = str('item_key')
-        values['value'] = 'item_value'
-        values = dict((str(k), v) for k, v in values.items())
-        # make test pass even without ordered dict
-        value_set = set(values.values())
-
-        for key, value in values.items():
-            self.assertEqual(traverse_obj(morsel, key), value,
-                             msg='Morsel should provide access to all values')
-        self.assertEqual(set(traverse_obj(morsel, Ellipsis)), value_set,
-                         msg='`...` should yield all values')
-        self.assertEqual(set(traverse_obj(morsel, lambda k, v: True)), value_set,
-                         msg='function key should yield all values')
-        self.assertIs(traverse_obj(morsel, [(None,), any]), morsel,
-                      msg='Morsel should not be implicitly changed to dict on usage')
-
-    def test_get_first(self):
-        self.assertEqual(get_first([{'a': None}, {'a': 'spam'}], 'a'), 'spam')
-
-    def test_dict_get(self):
-        FALSE_VALUES = {
-            'none': None,
-            'false': False,
-            'zero': 0,
-            'empty_string': '',
-            'empty_list': [],
-        }
-        d = FALSE_VALUES.copy()
-        d['a'] = 42
-        self.assertEqual(dict_get(d, 'a'), 42)
-        self.assertEqual(dict_get(d, 'b'), None)
-        self.assertEqual(dict_get(d, 'b', 42), 42)
-        self.assertEqual(dict_get(d, ('a', )), 42)
-        self.assertEqual(dict_get(d, ('b', 'a', )), 42)
-        self.assertEqual(dict_get(d, ('b', 'c', 'a', 'd', )), 42)
-        self.assertEqual(dict_get(d, ('b', 'c', )), None)
-        self.assertEqual(dict_get(d, ('b', 'c', ), 42), 42)
-        for key, false_value in FALSE_VALUES.items():
-            self.assertEqual(dict_get(d, ('b', 'c', key, )), None)
-            self.assertEqual(dict_get(d, ('b', 'c', key, ), skip_false_values=False), false_value)
-
-
-if __name__ == '__main__':
-    unittest.main()

test/test_utils.py

@@ -14,6 +14,7 @@ sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
 import io
 import itertools
 import json
+import re
 import xml.etree.ElementTree
 
 from youtube_dl.utils import (
@@ -27,6 +28,7 @@ from youtube_dl.utils import (
     DateRange,
     detect_exe_version,
     determine_ext,
+    dict_get,
     encode_base_n,
     encode_compat_str,
     encodeFilename,
@@ -42,6 +44,7 @@ from youtube_dl.utils import (
     get_element_by_attribute,
     get_elements_by_class,
     get_elements_by_attribute,
+    get_first,
     InAdvancePagedList,
     int_or_none,
     intlist_to_bytes,
@@ -81,11 +84,14 @@ from youtube_dl.utils import (
     sanitized_Request,
     shell_quote,
     smuggle_url,
+    str_or_none,
     str_to_int,
     strip_jsonp,
     strip_or_none,
     subtitles_filename,
+    T,
     timeconvert,
+    traverse_obj,
     try_call,
     unescapeHTML,
     unified_strdate,
@@ -126,6 +132,10 @@ from youtube_dl.compat import (
 
 class TestUtil(unittest.TestCase):
 
+    # yt-dlp shim
+    def assertCountEqual(self, expected, got, msg='count should be the same'):
+        return self.assertEqual(len(tuple(expected)), len(tuple(got)), msg=msg)
+
     def test_timeconvert(self):
         self.assertTrue(timeconvert('') is None)
         self.assertTrue(timeconvert('bougrg') is None)
@@ -730,6 +740,28 @@ class TestUtil(unittest.TestCase):
         self.assertRaises(
             ValueError, multipart_encode, {b'field': b'value'}, boundary='value')
 
+    def test_dict_get(self):
+        FALSE_VALUES = {
+            'none': None,
+            'false': False,
+            'zero': 0,
+            'empty_string': '',
+            'empty_list': [],
+        }
+        d = FALSE_VALUES.copy()
+        d['a'] = 42
+        self.assertEqual(dict_get(d, 'a'), 42)
+        self.assertEqual(dict_get(d, 'b'), None)
+        self.assertEqual(dict_get(d, 'b', 42), 42)
+        self.assertEqual(dict_get(d, ('a', )), 42)
+        self.assertEqual(dict_get(d, ('b', 'a', )), 42)
+        self.assertEqual(dict_get(d, ('b', 'c', 'a', 'd', )), 42)
+        self.assertEqual(dict_get(d, ('b', 'c', )), None)
+        self.assertEqual(dict_get(d, ('b', 'c', ), 42), 42)
+        for key, false_value in FALSE_VALUES.items():
+            self.assertEqual(dict_get(d, ('b', 'c', key, )), None)
+            self.assertEqual(dict_get(d, ('b', 'c', key, ), skip_false_values=False), false_value)
+
     def test_merge_dicts(self):
         self.assertEqual(merge_dicts({'a': 1}, {'b': 2}), {'a': 1, 'b': 2})
         self.assertEqual(merge_dicts({'a': 1}, {'a': 2}), {'a': 1})
@@ -1671,6 +1703,336 @@ Line 1
         self.assertEqual(variadic('spam', allowed_types=dict), 'spam')
         self.assertEqual(variadic('spam', allowed_types=[dict]), 'spam')
 
+    def test_traverse_obj(self):
+        str = compat_str
+        _TEST_DATA = {
+            100: 100,
+            1.2: 1.2,
+            'str': 'str',
+            'None': None,
+            '...': Ellipsis,
+            'urls': [
+                {'index': 0, 'url': 'https://www.example.com/0'},
+                {'index': 1, 'url': 'https://www.example.com/1'},
+            ],
+            'data': (
+                {'index': 2},
+                {'index': 3},
+            ),
+            'dict': {},
+        }
+
+        # define a pukka Iterable
+        def iter_range(stop):
+            for from_ in range(stop):
+                yield from_
+
+        # Test base functionality
+        self.assertEqual(traverse_obj(_TEST_DATA, ('str',)), 'str',
+                         msg='allow tuple path')
+        self.assertEqual(traverse_obj(_TEST_DATA, ['str']), 'str',
+                         msg='allow list path')
+        self.assertEqual(traverse_obj(_TEST_DATA, (value for value in ("str",))), 'str',
+                         msg='allow iterable path')
+        self.assertEqual(traverse_obj(_TEST_DATA, 'str'), 'str',
+                         msg='single items should be treated as a path')
+        self.assertEqual(traverse_obj(_TEST_DATA, None), _TEST_DATA)
+        self.assertEqual(traverse_obj(_TEST_DATA, 100), 100)
+        self.assertEqual(traverse_obj(_TEST_DATA, 1.2), 1.2)
+
+        # Test Ellipsis behavior
+        self.assertCountEqual(traverse_obj(_TEST_DATA, Ellipsis),
+                              (item for item in _TEST_DATA.values() if item not in (None, {})),
+                              msg='`...` should give all non-discarded values')
+        self.assertCountEqual(traverse_obj(_TEST_DATA, ('urls', 0, Ellipsis)), _TEST_DATA['urls'][0].values(),
+                              msg='`...` selection for dicts should select all values')
+        self.assertEqual(traverse_obj(_TEST_DATA, (Ellipsis, Ellipsis, 'url')),
+                         ['https://www.example.com/0', 'https://www.example.com/1'],
+                         msg='nested `...` queries should work')
+        self.assertCountEqual(traverse_obj(_TEST_DATA, (Ellipsis, Ellipsis, 'index')), iter_range(4),
+                              msg='`...` query result should be flattened')
+        self.assertEqual(traverse_obj(iter(range(4)), Ellipsis), list(range(4)),
+                         msg='`...` should accept iterables')
+
+        # Test function as key
+        self.assertEqual(traverse_obj(_TEST_DATA, lambda x, y: x == 'urls' and isinstance(y, list)),
+                         [_TEST_DATA['urls']],
+                         msg='function as query key should perform a filter based on (key, value)')
+        self.assertCountEqual(traverse_obj(_TEST_DATA, lambda _, x: isinstance(x[0], str)), set(('str',)),
+                              msg='exceptions in the query function should be caught')
+        self.assertEqual(traverse_obj(iter(range(4)), lambda _, x: x % 2 == 0), [0, 2],
+                         msg='function key should accept iterables')
+        if __debug__:
+            with self.assertRaises(Exception, msg='Wrong function signature should raise in debug'):
+                traverse_obj(_TEST_DATA, lambda a: Ellipsis)
+            with self.assertRaises(Exception, msg='Wrong function signature should raise in debug'):
+                traverse_obj(_TEST_DATA, lambda a, b, c: Ellipsis)
+
+        # Test set as key (transformation/type, like `expected_type`)
+        self.assertEqual(traverse_obj(_TEST_DATA, (Ellipsis, T(str.upper), )), ['STR'],
+                         msg='Function in set should be a transformation')
+        self.assertEqual(traverse_obj(_TEST_DATA, (Ellipsis, T(str))), ['str'],
+                         msg='Type in set should be a type filter')
+        self.assertEqual(traverse_obj(_TEST_DATA, T(dict)), _TEST_DATA,
+                         msg='A single set should be wrapped into a path')
+        self.assertEqual(traverse_obj(_TEST_DATA, (Ellipsis, T(str.upper))), ['STR'],
+                         msg='Transformation function should not raise')
+        self.assertEqual(traverse_obj(_TEST_DATA, (Ellipsis, T(str_or_none))),
+                         [item for item in map(str_or_none, _TEST_DATA.values()) if item is not None],
+                         msg='Function in set should be a transformation')
+        if __debug__:
+            with self.assertRaises(Exception, msg='Sets with length != 1 should raise in debug'):
+                traverse_obj(_TEST_DATA, set())
+            with self.assertRaises(Exception, msg='Sets with length != 1 should raise in debug'):
+                traverse_obj(_TEST_DATA, set((str.upper, str)))
+
+        # Test `slice` as a key
+        _SLICE_DATA = [0, 1, 2, 3, 4]
+        self.assertEqual(traverse_obj(_TEST_DATA, ('dict', slice(1))), None,
+                         msg='slice on a dictionary should not throw')
+        self.assertEqual(traverse_obj(_SLICE_DATA, slice(1)), _SLICE_DATA[:1],
+                         msg='slice key should apply slice to sequence')
+        self.assertEqual(traverse_obj(_SLICE_DATA, slice(1, 2)), _SLICE_DATA[1:2],
+                         msg='slice key should apply slice to sequence')
+        self.assertEqual(traverse_obj(_SLICE_DATA, slice(1, 4, 2)), _SLICE_DATA[1:4:2],
+                         msg='slice key should apply slice to sequence')
+
+        # Test alternative paths
+        self.assertEqual(traverse_obj(_TEST_DATA, 'fail', 'str'), 'str',
+                         msg='multiple `paths` should be treated as alternative paths')
+        self.assertEqual(traverse_obj(_TEST_DATA, 'str', 100), 'str',
+                         msg='alternatives should exit early')
+        self.assertEqual(traverse_obj(_TEST_DATA, 'fail', 'fail'), None,
+                         msg='alternatives should return `default` if exhausted')
+        self.assertEqual(traverse_obj(_TEST_DATA, (Ellipsis, 'fail'), 100), 100,
+                         msg='alternatives should track their own branching return')
+        self.assertEqual(traverse_obj(_TEST_DATA, ('dict', Ellipsis), ('data', Ellipsis)), list(_TEST_DATA['data']),
+                         msg='alternatives on empty objects should search further')
+
+        # Test branch and path nesting
+        self.assertEqual(traverse_obj(_TEST_DATA, ('urls', (3, 0), 'url')), ['https://www.example.com/0'],
+                         msg='tuple as key should be treated as branches')
+        self.assertEqual(traverse_obj(_TEST_DATA, ('urls', [3, 0], 'url')), ['https://www.example.com/0'],
+                         msg='list as key should be treated as branches')
+        self.assertEqual(traverse_obj(_TEST_DATA, ('urls', ((1, 'fail'), (0, 'url')))), ['https://www.example.com/0'],
+                         msg='double nesting in path should be treated as paths')
+        self.assertEqual(traverse_obj(['0', [1, 2]], [(0, 1), 0]), [1],
+                         msg='do not fail early on branching')
+        self.assertCountEqual(traverse_obj(_TEST_DATA, ('urls', ((1, ('fail', 'url')), (0, 'url')))),
+                              ['https://www.example.com/0', 'https://www.example.com/1'],
+                              msg='triple nesting in path should be treated as branches')
+        self.assertEqual(traverse_obj(_TEST_DATA, ('urls', ('fail', (Ellipsis, 'url')))),
+                         ['https://www.example.com/0', 'https://www.example.com/1'],
+                         msg='ellipsis as branch path start gets flattened')
+
+        # Test dictionary as key
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: 100, 1: 1.2}), {0: 100, 1: 1.2},
+                         msg='dict key should result in a dict with the same keys')
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: ('urls', 0, 'url')}),
+                         {0: 'https://www.example.com/0'},
+                         msg='dict key should allow paths')
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: ('urls', (3, 0), 'url')}),
+                         {0: ['https://www.example.com/0']},
+                         msg='tuple in dict path should be treated as branches')
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: ('urls', ((1, 'fail'), (0, 'url')))}),
+                         {0: ['https://www.example.com/0']},
+                         msg='double nesting in dict path should be treated as paths')
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: ('urls', ((1, ('fail', 'url')), (0, 'url')))}),
+                         {0: ['https://www.example.com/1', 'https://www.example.com/0']},
+                         msg='triple nesting in dict path should be treated as branches')
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: 'fail'}), {},
+                         msg='remove `None` values when top level dict key fails')
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: 'fail'}, default=Ellipsis), {0: Ellipsis},
+                         msg='use `default` if key fails and `default`')
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: 'dict'}), {},
+                         msg='remove empty values when dict key')
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: 'dict'}, default=Ellipsis), {0: Ellipsis},
+                         msg='use `default` when dict key and a default')
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: {0: 'fail'}}), {},
+                         msg='remove empty values when nested dict key fails')
+        self.assertEqual(traverse_obj(None, {0: 'fail'}), {},
+                         msg='default to dict if pruned')
+        self.assertEqual(traverse_obj(None, {0: 'fail'}, default=Ellipsis), {0: Ellipsis},
+                         msg='default to dict if pruned and default is given')
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: {0: 'fail'}}, default=Ellipsis), {0: {0: Ellipsis}},
+                         msg='use nested `default` when nested dict key fails and `default`')
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: ('dict', Ellipsis)}), {},
+                         msg='remove key if branch in dict key not successful')
+
+        # Testing default parameter behavior
+        _DEFAULT_DATA = {'None': None, 'int': 0, 'list': []}
+        self.assertEqual(traverse_obj(_DEFAULT_DATA, 'fail'), None,
+                         msg='default value should be `None`')
+        self.assertEqual(traverse_obj(_DEFAULT_DATA, 'fail', 'fail', default=Ellipsis), Ellipsis,
+                         msg='chained fails should result in default')
+        self.assertEqual(traverse_obj(_DEFAULT_DATA, 'None', 'int'), 0,
+                         msg='should not short cirquit on `None`')
+        self.assertEqual(traverse_obj(_DEFAULT_DATA, 'fail', default=1), 1,
+                         msg='invalid dict key should result in `default`')
+        self.assertEqual(traverse_obj(_DEFAULT_DATA, 'None', default=1), 1,
+                         msg='`None` is a deliberate sentinel and should become `default`')
+        self.assertEqual(traverse_obj(_DEFAULT_DATA, ('list', 10)), None,
+                         msg='`IndexError` should result in `default`')
+        self.assertEqual(traverse_obj(_DEFAULT_DATA, (Ellipsis, 'fail'), default=1), 1,
+                         msg='if branched but not successful return `default` if defined, not `[]`')
+        self.assertEqual(traverse_obj(_DEFAULT_DATA, (Ellipsis, 'fail'), default=None), None,
+                         msg='if branched but not successful return `default` even if `default` is `None`')
+        self.assertEqual(traverse_obj(_DEFAULT_DATA, (Ellipsis, 'fail')), [],
+                         msg='if branched but not successful return `[]`, not `default`')
+        self.assertEqual(traverse_obj(_DEFAULT_DATA, ('list', Ellipsis)), [],
+                         msg='if branched but object is empty return `[]`, not `default`')
+        self.assertEqual(traverse_obj(None, Ellipsis), [],
+                         msg='if branched but object is `None` return `[]`, not `default`')
+        self.assertEqual(traverse_obj({0: None}, (0, Ellipsis)), [],
+                         msg='if branched but state is `None` return `[]`, not `default`')
+
+        branching_paths = [
+            ('fail', Ellipsis),
+            (Ellipsis, 'fail'),
+            100 * ('fail',) + (Ellipsis,),
+            (Ellipsis,) + 100 * ('fail',),
+        ]
+        for branching_path in branching_paths:
+            self.assertEqual(traverse_obj({}, branching_path), [],
+                             msg='if branched but state is `None`, return `[]` (not `default`)')
+            self.assertEqual(traverse_obj({}, 'fail', branching_path), [],
+                             msg='if branching in last alternative and previous did not match, return `[]` (not `default`)')
+            self.assertEqual(traverse_obj({0: 'x'}, 0, branching_path), 'x',
+                             msg='if branching in last alternative and previous did match, return single value')
+            self.assertEqual(traverse_obj({0: 'x'}, branching_path, 0), 'x',
+                             msg='if branching in first alternative and non-branching path does match, return single value')
+            self.assertEqual(traverse_obj({}, branching_path, 'fail'), None,
+                             msg='if branching in first alternative and non-branching path does not match, return `default`')
+
+        # Testing expected_type behavior
+        _EXPECTED_TYPE_DATA = {'str': 'str', 'int': 0}
+        self.assertEqual(traverse_obj(_EXPECTED_TYPE_DATA, 'str', expected_type=str),
+                         'str', msg='accept matching `expected_type` type')
+        self.assertEqual(traverse_obj(_EXPECTED_TYPE_DATA, 'str', expected_type=int),
+                         None, msg='reject non-matching `expected_type` type')
+        self.assertEqual(traverse_obj(_EXPECTED_TYPE_DATA, 'int', expected_type=lambda x: str(x)),
+                         '0', msg='transform type using type function')
+        self.assertEqual(traverse_obj(_EXPECTED_TYPE_DATA, 'str', expected_type=lambda _: 1 / 0),
+                         None, msg='wrap expected_type function in try_call')
+        self.assertEqual(traverse_obj(_EXPECTED_TYPE_DATA, Ellipsis, expected_type=str),
+                         ['str'], msg='eliminate items that expected_type fails on')
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: 100, 1: 1.2}, expected_type=int),
+                         {0: 100}, msg='type as expected_type should filter dict values')
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: 100, 1: 1.2, 2: 'None'}, expected_type=str_or_none),
+                         {0: '100', 1: '1.2'}, msg='function as expected_type should transform dict values')
+        self.assertEqual(traverse_obj(_TEST_DATA, ({0: 1.2}, 0, set((int_or_none,))), expected_type=int),
+                         1, msg='expected_type should not filter non-final dict values')
+        self.assertEqual(traverse_obj(_TEST_DATA, {0: {0: 100, 1: 'str'}}, expected_type=int),
+                         {0: {0: 100}}, msg='expected_type should transform deep dict values')
+        self.assertEqual(traverse_obj(_TEST_DATA, [({0: '...'}, {0: '...'})], expected_type=type(Ellipsis)),
+                         [{0: Ellipsis}, {0: Ellipsis}], msg='expected_type should transform branched dict values')
+        self.assertEqual(traverse_obj({1: {3: 4}}, [(1, 2), 3], expected_type=int),
+                         [4], msg='expected_type regression for type matching in tuple branching')
+        self.assertEqual(traverse_obj(_TEST_DATA, ['data', Ellipsis], expected_type=int),
+                         [], msg='expected_type regression for type matching in dict result')
+
+        # Test get_all behavior
+        _GET_ALL_DATA = {'key': [0, 1, 2]}
+        self.assertEqual(traverse_obj(_GET_ALL_DATA, ('key', Ellipsis), get_all=False), 0,
+                         msg='if not `get_all`, return only first matching value')
+        self.assertEqual(traverse_obj(_GET_ALL_DATA, Ellipsis, get_all=False), [0, 1, 2],
+                         msg='do not overflatten if not `get_all`')
+
+        # Test casesense behavior
+        _CASESENSE_DATA = {
+            'KeY': 'value0',
+            0: {
+                'KeY': 'value1',
+                0: {'KeY': 'value2'},
+            },
+            # FULLWIDTH LATIN CAPITAL LETTER K
+            '\uff2bey': 'value3',
+        }
+        self.assertEqual(traverse_obj(_CASESENSE_DATA, 'key'), None,
+                         msg='dict keys should be case sensitive unless `casesense`')
+        self.assertEqual(traverse_obj(_CASESENSE_DATA, 'keY',
+                                      casesense=False), 'value0',
+                         msg='allow non matching key case if `casesense`')
+        self.assertEqual(traverse_obj(_CASESENSE_DATA, '\uff4bey',  # FULLWIDTH LATIN SMALL LETTER K
+                                      casesense=False), 'value3',
+                         msg='allow non matching Unicode key case if `casesense`')
+        self.assertEqual(traverse_obj(_CASESENSE_DATA, (0, ('keY',)),
+                                      casesense=False), ['value1'],
+                         msg='allow non matching key case in branch if `casesense`')
+        self.assertEqual(traverse_obj(_CASESENSE_DATA, (0, ((0, 'keY'),)),
+                                      casesense=False), ['value2'],
+                         msg='allow non matching key case in branch path if `casesense`')
+
+        # Test traverse_string behavior
+        _TRAVERSE_STRING_DATA = {'str': 'str', 1.2: 1.2}
+        self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, ('str', 0)), None,
+                         msg='do not traverse into string if not `traverse_string`')
+        self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, ('str', 0),
+                                      _traverse_string=True), 's',
+                         msg='traverse into string if `traverse_string`')
+        self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, (1.2, 1),
+                                      _traverse_string=True), '.',
+                         msg='traverse into converted data if `traverse_string`')
+        self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, ('str', Ellipsis),
+                                      _traverse_string=True), 'str',
+                         msg='`...` should result in string (same value) if `traverse_string`')
+        self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, ('str', slice(0, None, 2)),
+                                      _traverse_string=True), 'sr',
+                         msg='`slice` should result in string if `traverse_string`')
+        self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, ('str', lambda i, v: i or v == 's'),
+                                      _traverse_string=True), 'str',
+                         msg='function should result in string if `traverse_string`')
+        self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, ('str', (0, 2)),
+                                      _traverse_string=True), ['s', 'r'],
+                         msg='branching should result in list if `traverse_string`')
+        self.assertEqual(traverse_obj({}, (0, Ellipsis), _traverse_string=True), [],
+                         msg='branching should result in list if `traverse_string`')
+        self.assertEqual(traverse_obj({}, (0, lambda x, y: True), _traverse_string=True), [],
+                         msg='branching should result in list if `traverse_string`')
+        self.assertEqual(traverse_obj({}, (0, slice(1)), _traverse_string=True), [],
+                         msg='branching should result in list if `traverse_string`')
+
+        # Test is_user_input behavior
+        _IS_USER_INPUT_DATA = {'range8': list(range(8))}
+        self.assertEqual(traverse_obj(_IS_USER_INPUT_DATA, ('range8', '3'),
+                                      _is_user_input=True), 3,
+                         msg='allow for string indexing if `is_user_input`')
+        self.assertCountEqual(traverse_obj(_IS_USER_INPUT_DATA, ('range8', '3:'),
+                                           _is_user_input=True), tuple(range(8))[3:],
+                              msg='allow for string slice if `is_user_input`')
+        self.assertCountEqual(traverse_obj(_IS_USER_INPUT_DATA, ('range8', ':4:2'),
+                                           _is_user_input=True), tuple(range(8))[:4:2],
+                              msg='allow step in string slice if `is_user_input`')
+        self.assertCountEqual(traverse_obj(_IS_USER_INPUT_DATA, ('range8', ':'),
+                                           _is_user_input=True), range(8),
+                              msg='`:` should be treated as `...` if `is_user_input`')
+        with self.assertRaises(TypeError, msg='too many params should result in error'):
+            traverse_obj(_IS_USER_INPUT_DATA, ('range8', ':::'), _is_user_input=True)
+
+        # Test re.Match as input obj
+        mobj = re.match(r'^0(12)(?P<group>3)(4)?$', '0123')
+        self.assertEqual(traverse_obj(mobj, Ellipsis), [x for x in mobj.groups() if x is not None],
+                         msg='`...` on a `re.Match` should give its `groups()`')
+        self.assertEqual(traverse_obj(mobj, lambda k, _: k in (0, 2)), ['0123', '3'],
+                         msg='function on a `re.Match` should give groupno, value starting at 0')
+        self.assertEqual(traverse_obj(mobj, 'group'), '3',
+                         msg='str key on a `re.Match` should give group with that name')
+        self.assertEqual(traverse_obj(mobj, 2), '3',
+                         msg='int key on a `re.Match` should give group with that name')
+        self.assertEqual(traverse_obj(mobj, 'gRoUp', casesense=False), '3',
+                         msg='str key on a `re.Match` should respect casesense')
+        self.assertEqual(traverse_obj(mobj, 'fail'), None,
+                         msg='failing str key on a `re.Match` should return `default`')
+        self.assertEqual(traverse_obj(mobj, 'gRoUpS', casesense=False), None,
+                         msg='failing str key on a `re.Match` should return `default`')
+        self.assertEqual(traverse_obj(mobj, 8), None,
+                         msg='failing int key on a `re.Match` should return `default`')
+        self.assertEqual(traverse_obj(mobj, lambda k, _: k in (0, 'group')), ['0123', '3'],
+                         msg='function on a `re.Match` should give group name as well')
+
+    def test_get_first(self):
+        self.assertEqual(get_first([{'a': None}, {'a': 'spam'}], 'a'), 'spam')
+
     def test_join_nonempty(self):
         self.assertEqual(join_nonempty('a', 'b'), 'a-b')
         self.assertEqual(join_nonempty(

youtube_dl/compat.py

@@ -2719,222 +2719,8 @@ if sys.version_info < (2, 7):
         if isinstance(xpath, compat_str):
             xpath = xpath.encode('ascii')
         return xpath
-
-    # further code below based on CPython 2.7 source
-    import functools
-
-    _xpath_tokenizer_re = re.compile(r'''(?x)
-        (                                   # (1)
-            '[^']*'|"[^"]*"|                # quoted strings, or
-            ::|//?|\.\.|\(\)|[/.*:[\]()@=]  # navigation specials
-        )|                                  # or (2)
-        ((?:\{[^}]+\})?[^/[\]()@=\s]+)|     # token: optional {ns}, no specials
-        \s+                                 # or white space
-    ''')
-
-    def _xpath_tokenizer(pattern, namespaces=None):
-        for token in _xpath_tokenizer_re.findall(pattern):
-            tag = token[1]
-            if tag and tag[0] != "{" and ":" in tag:
-                try:
-                    if not namespaces:
-                        raise KeyError
-                    prefix, uri = tag.split(":", 1)
-                    yield token[0], "{%s}%s" % (namespaces[prefix], uri)
-                except KeyError:
-                    raise SyntaxError("prefix %r not found in prefix map" % prefix)
-            else:
-                yield token
-
-    def _get_parent_map(context):
-        parent_map = context.parent_map
-        if parent_map is None:
-            context.parent_map = parent_map = {}
-            for p in context.root.getiterator():
-                for e in p:
-                    parent_map[e] = p
-        return parent_map
-
-    def _select(context, result, filter_fn=lambda *_: True):
-        for elem in result:
-            for e in elem:
-                if filter_fn(e, elem):
-                    yield e
-
-    def _prepare_child(next_, token):
-        tag = token[1]
-        return functools.partial(_select, filter_fn=lambda e, _: e.tag == tag)
-
-    def _prepare_star(next_, token):
-        return _select
-
-    def _prepare_self(next_, token):
-        return lambda _, result: (e for e in result)
-
-    def _prepare_descendant(next_, token):
-        token = next(next_)
-        if token[0] == "*":
-            tag = "*"
-        elif not token[0]:
-            tag = token[1]
-        else:
-            raise SyntaxError("invalid descendant")
-
-        def select(context, result):
-            for elem in result:
-                for e in elem.getiterator(tag):
-                    if e is not elem:
-                        yield e
-        return select
-
-    def _prepare_parent(next_, token):
-        def select(context, result):
-            # FIXME: raise error if .. is applied at toplevel?
-            parent_map = _get_parent_map(context)
-            result_map = {}
-            for elem in result:
-                if elem in parent_map:
-                    parent = parent_map[elem]
-                    if parent not in result_map:
-                        result_map[parent] = None
-                        yield parent
-        return select
-
-    def _prepare_predicate(next_, token):
-        signature = []
-        predicate = []
-        for token in next_:
-            if token[0] == "]":
-                break
-            if token[0] and token[0][:1] in "'\"":
-                token = "'", token[0][1:-1]
-            signature.append(token[0] or "-")
-            predicate.append(token[1])
-
-        def select(context, result, filter_fn=lambda _: True):
-            for elem in result:
-                if filter_fn(elem):
-                    yield elem
-
-        signature = "".join(signature)
-        # use signature to determine predicate type
-        if signature == "@-":
-            # [@attribute] predicate
-            key = predicate[1]
-            return functools.partial(
-                select, filter_fn=lambda el: el.get(key) is not None)
-        if signature == "@-='":
-            # [@attribute='value']
-            key = predicate[1]
-            value = predicate[-1]
-            return functools.partial(
-                select, filter_fn=lambda el: el.get(key) == value)
-        if signature == "-" and not re.match(r"\d+$", predicate[0]):
-            # [tag]
-            tag = predicate[0]
-            return functools.partial(
-                select, filter_fn=lambda el: el.find(tag) is not None)
-        if signature == "-='" and not re.match(r"\d+$", predicate[0]):
-            # [tag='value']
-            tag = predicate[0]
-            value = predicate[-1]
-
-            def itertext(el):
-                for e in el.getiterator():
-                    e = e.text
-                    if e:
-                        yield e
-
-            def select(context, result):
-                for elem in result:
-                    for e in elem.findall(tag):
-                        if "".join(itertext(e)) == value:
-                            yield elem
-                            break
-            return select
-        if signature == "-" or signature == "-()" or signature == "-()-":
-            # [index] or [last()] or [last()-index]
-            if signature == "-":
-                index = int(predicate[0]) - 1
-            else:
-                if predicate[0] != "last":
-                    raise SyntaxError("unsupported function")
-                if signature == "-()-":
-                    try:
-                        index = int(predicate[2]) - 1
-                    except ValueError:
-                        raise SyntaxError("unsupported expression")
-                else:
-                    index = -1
-
-            def select(context, result):
-                parent_map = _get_parent_map(context)
-                for elem in result:
-                    try:
-                        parent = parent_map[elem]
-                        # FIXME: what if the selector is "*" ?
-                        elems = list(parent.findall(elem.tag))
-                        if elems[index] is elem:
-                            yield elem
-                    except (IndexError, KeyError):
-                        pass
-            return select
-        raise SyntaxError("invalid predicate")
-
-    ops = {
-        "": _prepare_child,
-        "*": _prepare_star,
-        ".": _prepare_self,
-        "..": _prepare_parent,
-        "//": _prepare_descendant,
-        "[": _prepare_predicate,
-    }
-
-    _cache = {}
-
-    class _SelectorContext:
-        parent_map = None
-
-        def __init__(self, root):
-            self.root = root
-
-    ##
-    # Generate all matching objects.
-
-    def compat_etree_iterfind(elem, path, namespaces=None):
-        # compile selector pattern
-        if path[-1:] == "/":
-            path = path + "*"  # implicit all (FIXME: keep this?)
-        try:
-            selector = _cache[path]
-        except KeyError:
-            if len(_cache) > 100:
-                _cache.clear()
-            if path[:1] == "/":
-                raise SyntaxError("cannot use absolute path on element")
-            tokens = _xpath_tokenizer(path, namespaces)
-            selector = []
-            for token in tokens:
-                if token[0] == "/":
-                    continue
-                try:
-                    selector.append(ops[token[0]](tokens, token))
-                except StopIteration:
-                    raise SyntaxError("invalid path")
-            _cache[path] = selector
-        # execute selector pattern
-        result = [elem]
-        context = _SelectorContext(elem)
-        for select in selector:
-            result = select(context, result)
-        return result
-
-    # end of code based on CPython 2.7 source
-
-
 else:
     compat_xpath = lambda xpath: xpath
-    compat_etree_iterfind = lambda element, match: element.iterfind(match)
 
 
 compat_os_name = os._name if os.name == 'java' else os.name
@@ -2970,7 +2756,7 @@ except (AssertionError, UnicodeEncodeError):
 
 
 def compat_ord(c):
-    if isinstance(c, int):
+    if type(c) is int:
         return c
     else:
         return ord(c)
@@ -3169,7 +2955,7 @@ except ImportError:
             return self
 
         def __exit__(self, exc_type, exc_val, exc_tb):
-            return exc_type is not None and issubclass(exc_type, self._exceptions or tuple())
+            return exc_val is not None and isinstance(exc_val, self._exceptions or tuple())
 
 
 # subprocess.Popen context manager
@@ -3522,7 +3308,6 @@ __all__ = [
     'compat_contextlib_suppress',
     'compat_ctypes_WINFUNCTYPE',
     'compat_etree_fromstring',
-    'compat_etree_iterfind',
     'compat_filter',
     'compat_get_terminal_size',
     'compat_getenv',

youtube_dl/extractor/common.py

@@ -1169,10 +1169,10 @@ class InfoExtractor(object):
     def _get_netrc_login_info(self, netrc_machine=None):
         username = None
         password = None
+        netrc_machine = netrc_machine or self._NETRC_MACHINE
 
         if self._downloader.params.get('usenetrc', False):
             try:
-                netrc_machine = netrc_machine or self._NETRC_MACHINE
                 info = netrc.netrc().authenticators(netrc_machine)
                 if info is not None:
                     username = info[0]
@@ -1180,7 +1180,7 @@ class InfoExtractor(object):
                 else:
                     raise netrc.NetrcParseError(
                         'No authenticators for %s' % netrc_machine)
-            except (AttributeError, IOError, netrc.NetrcParseError) as err:
+            except (IOError, netrc.NetrcParseError) as err:
                 self._downloader.report_warning(
                     'parsing .netrc: %s' % error_to_compat_str(err))
 
@@ -1490,18 +1490,14 @@ class InfoExtractor(object):
         return dict((k, v) for k, v in info.items() if v is not None)
 
     def _search_nextjs_data(self, webpage, video_id, **kw):
-        # ..., *, transform_source=None, fatal=True, default=NO_DEFAULT
+        nkw = dict((k, v) for k, v in kw.items() if k in ('transform_source', 'fatal'))
-
+        kw.pop('transform_source', None)
-        # TODO: remove this backward compat
+        next_data = self._search_regex(
-        default = kw.get('default', NO_DEFAULT)
+            r'''<script[^>]+\bid\s*=\s*('|")__NEXT_DATA__\1[^>]*>(?P<nd>[^<]+)</script>''',
-        if default == '{}':
+            webpage, 'next.js data', group='nd', **kw)
-            kw['default'] = {}
+        if not next_data:
-            kw = compat_kwargs(kw)
+            return {}
-
+        return self._parse_json(next_data, video_id, **nkw)
-        return self._search_json(
-            r'''<script\s[^>]*?\bid\s*=\s*('|")__NEXT_DATA__\1[^>]*>''',
-            webpage, 'next.js data', video_id, end_pattern='</script>',
-            **kw)
 
     def _search_nuxt_data(self, webpage, video_id, *args, **kwargs):
         """Parses Nuxt.js metadata. This works as long as the function __NUXT__ invokes is a pure function"""
@@ -3300,16 +3296,12 @@ class InfoExtractor(object):
         return ret
 
     @classmethod
-    def _merge_subtitles(cls, subtitle_dict1, *subtitle_dicts, **kwargs):
+    def _merge_subtitles(cls, subtitle_dict1, subtitle_dict2):
-        """ Merge subtitle dictionaries, language by language. """
+        """ Merge two subtitle dictionaries, language by language. """
-
+        ret = dict(subtitle_dict1)
-        # ..., * , target=None
+        for lang in subtitle_dict2:
-        target = kwargs.get('target') or dict(subtitle_dict1)
+            ret[lang] = cls._merge_subtitle_items(subtitle_dict1.get(lang, []), subtitle_dict2[lang])
-
+        return ret
-        for subtitle_dict in subtitle_dicts:
-            for lang in subtitle_dict:
-                target[lang] = cls._merge_subtitle_items(target.get(lang, []), subtitle_dict[lang])
-        return target
 
     def extract_automatic_captions(self, *args, **kwargs):
         if (self._downloader.params.get('writeautomaticsub', False)
@@ -3342,29 +3334,6 @@ class InfoExtractor(object):
     def _generic_title(self, url):
         return compat_urllib_parse_unquote(os.path.splitext(url_basename(url))[0])
 
-    def _yes_playlist(self, playlist_id, video_id, *args, **kwargs):
-        # smuggled_data=None, *, playlist_label='playlist', video_label='video'
-        smuggled_data = args[0] if len(args) == 1 else kwargs.get('smuggled_data')
-        playlist_label = kwargs.get('playlist_label', 'playlist')
-        video_label = kwargs.get('video_label', 'video')
-
-        if not playlist_id or not video_id:
-            return not video_id
-
-        no_playlist = (smuggled_data or {}).get('force_noplaylist')
-        if no_playlist is not None:
-            return not no_playlist
-
-        video_id = '' if video_id is True else ' ' + video_id
-        noplaylist = self.get_param('noplaylist')
-        self.to_screen(
-            'Downloading just the {0}{1} because of --no-playlist'.format(video_label, video_id)
-            if noplaylist else
-            'Downloading {0}{1} - add --no-playlist to download just the {2}{3}'.format(
-                playlist_label, '' if playlist_id is True else ' ' + playlist_id,
-                video_label, video_id))
-        return not noplaylist
-
 
 class SearchInfoExtractor(InfoExtractor):
     """

youtube_dl/traversal.py

@@ -1,10 +0,0 @@
-# coding: utf-8
-
-# TODO: move these utils.fns here and move import to utils
-# flake8: noqa
-from .utils import (
-    dict_get,
-    get_first,
-    T,
-    traverse_obj,
-)

youtube_dl/utils.py

@@ -49,14 +49,11 @@ from .compat import (
     compat_cookiejar,
     compat_ctypes_WINFUNCTYPE,
     compat_datetime_timedelta_total_seconds,
-    compat_etree_Element,
     compat_etree_fromstring,
-    compat_etree_iterfind,
     compat_expanduser,
     compat_html_entities,
     compat_html_entities_html5,
     compat_http_client,
-    compat_http_cookies,
     compat_integer_types,
     compat_kwargs,
     compat_ncompress as ncompress,
@@ -6256,16 +6253,15 @@ if __debug__:
 
 def traverse_obj(obj, *paths, **kwargs):
     """
-    Safely traverse nested `dict`s and `Iterable`s, etc
+    Safely traverse nested `dict`s and `Iterable`s
 
     >>> obj = [{}, {"key": "value"}]
     >>> traverse_obj(obj, (1, "key"))
-    'value'
+    "value"
 
     Each of the provided `paths` is tested and the first producing a valid result will be returned.
     The next path will also be tested if the path branched but no results could be found.
-    Supported values for traversal are `Mapping`, `Iterable`, `re.Match`, `xml.etree.ElementTree`
+    Supported values for traversal are `Mapping`, `Iterable` and `re.Match`.
-    (xpath) and `http.cookies.Morsel`.
     Unhelpful values (`{}`, `None`) are treated as the absence of a value and discarded.
 
     The paths will be wrapped in `variadic`, so that `'key'` is conveniently the same as `('key', )`.
@@ -6273,9 +6269,8 @@ def traverse_obj(obj, *paths, **kwargs):
     The keys in the path can be one of:
         - `None`:           Return the current object.
         - `set`:            Requires the only item in the set to be a type or function,
-                            like `{type}`/`{type, type, ...}`/`{func}`. If one or more `type`s,
+                            like `{type}`/`{func}`. If a `type`, returns only values
-                            return only values that have one of the types. If a function,
+                            of this type. If a function, returns `func(obj)`.
-                            return `func(obj)`.
         - `str`/`int`:      Return `obj[key]`. For `re.Match`, return `obj.group(key)`.
         - `slice`:          Branch out and return all values in `obj[key]`.
         - `Ellipsis`:       Branch out and return a list of all values.
@@ -6287,10 +6282,8 @@ def traverse_obj(obj, *paths, **kwargs):
                             For `Iterable`s, `key` is the enumeration count of the value.
                             For `re.Match`es, `key` is the group number (0 = full match)
                             as well as additionally any group names, if given.
-        - `dict`:           Transform the current object and return a matching dict.
+        - `dict`            Transform the current object and return a matching dict.
                             Read as: `{key: traverse_obj(obj, path) for key, path in dct.items()}`.
-        - `any`-builtin:    Take the first matching object and return it, resetting branching.
-        - `all`-builtin:    Take all matching objects and return them as a list, resetting branching.
 
         `tuple`, `list`, and `dict` all support nested paths and branches.
 
@@ -6306,8 +6299,10 @@ def traverse_obj(obj, *paths, **kwargs):
     @param get_all          If `False`, return the first matching result, otherwise all matching ones.
     @param casesense        If `False`, consider string dictionary keys as case insensitive.
 
-    The following is only meant to be used by YoutubeDL.prepare_outtmpl and is not part of the API
+    The following are only meant to be used by YoutubeDL.prepare_outtmpl and are not part of the API
 
+    @param _is_user_input    Whether the keys are generated from user input.
+                            If `True` strings get converted to `int`/`slice` if needed.
     @param _traverse_string  Whether to traverse into objects as strings.
                             If `True`, any non-compatible object will first be
                             converted into a string and then traversed into.
@@ -6327,6 +6322,7 @@ def traverse_obj(obj, *paths, **kwargs):
     expected_type = kwargs.get('expected_type')
     get_all = kwargs.get('get_all', True)
     casesense = kwargs.get('casesense', True)
+    _is_user_input = kwargs.get('_is_user_input', False)
     _traverse_string = kwargs.get('_traverse_string', False)
 
     # instant compat
@@ -6340,8 +6336,10 @@ def traverse_obj(obj, *paths, **kwargs):
         type_test = lambda val: try_call(expected_type or IDENTITY, args=(val,))
 
     def lookup_or_none(v, k, getter=None):
-        with compat_contextlib_suppress(LookupError):
+        try:
             return getter(v, k) if getter else v[k]
+        except IndexError:
+            return None
 
     def from_iterable(iterables):
         # chain.from_iterable(['ABC', 'DEF']) --> A B C D E F
@@ -6363,13 +6361,12 @@ def traverse_obj(obj, *paths, **kwargs):
             result = obj
 
         elif isinstance(key, set):
-            assert len(key) >= 1, 'At least one item is required in a `set` key'
+            assert len(key) == 1, 'Set should only be used to wrap a single item'
-            if all(isinstance(item, type) for item in key):
+            item = next(iter(key))
-                result = obj if isinstance(obj, tuple(key)) else None
+            if isinstance(item, type):
+                result = obj if isinstance(obj, item) else None
             else:
-                item = next(iter(key))
+                result = try_call(item, args=(obj,))
-                assert len(key) == 1, 'Multiple items in a `set` key must all be types'
-                result = try_call(item, args=(obj,)) if not isinstance(item, type) else None
 
         elif isinstance(key, (list, tuple)):
             branching = True
@@ -6378,11 +6375,9 @@ def traverse_obj(obj, *paths, **kwargs):
 
         elif key is Ellipsis:
             branching = True
-            if isinstance(obj, compat_http_cookies.Morsel):
-                obj = dict(obj, key=obj.key, value=obj.value)
             if isinstance(obj, compat_collections_abc.Mapping):
                 result = obj.values()
-            elif is_iterable_like(obj, (compat_collections_abc.Iterable, compat_etree_Element)):
+            elif is_iterable_like(obj):
                 result = obj
             elif isinstance(obj, compat_re_Match):
                 result = obj.groups()
@@ -6394,11 +6389,9 @@ def traverse_obj(obj, *paths, **kwargs):
 
         elif callable(key):
             branching = True
-            if isinstance(obj, compat_http_cookies.Morsel):
-                obj = dict(obj, key=obj.key, value=obj.value)
             if isinstance(obj, compat_collections_abc.Mapping):
                 iter_obj = obj.items()
-            elif is_iterable_like(obj, (compat_collections_abc.Iterable, compat_etree_Element)):
+            elif is_iterable_like(obj):
                 iter_obj = enumerate(obj)
             elif isinstance(obj, compat_re_Match):
                 iter_obj = itertools.chain(
@@ -6420,8 +6413,6 @@ def traverse_obj(obj, *paths, **kwargs):
                           if v is not None or default is not NO_DEFAULT) or None
 
         elif isinstance(obj, compat_collections_abc.Mapping):
-            if isinstance(obj, compat_http_cookies.Morsel):
-                obj = dict(obj, key=obj.key, value=obj.value)
             result = (try_call(obj.get, args=(key,))
                       if casesense or try_call(obj.__contains__, args=(key,))
                       else next((v for k, v in obj.items() if casefold(k) == key), None))
@@ -6439,40 +6430,12 @@ def traverse_obj(obj, *paths, **kwargs):
         else:
             result = None
             if isinstance(key, (int, slice)):
-                if is_iterable_like(obj, (compat_collections_abc.Sequence, compat_etree_Element)):
+                if is_iterable_like(obj, compat_collections_abc.Sequence):
                     branching = isinstance(key, slice)
                     result = lookup_or_none(obj, key)
                 elif _traverse_string:
                     result = lookup_or_none(str(obj), key)
 
-            elif isinstance(obj, compat_etree_Element) and isinstance(key, str):
-                xpath, _, special = key.rpartition('/')
-                if not special.startswith('@') and not special.endswith('()'):
-                    xpath = key
-                    special = None
-
-                # Allow abbreviations of relative paths, absolute paths error
-                if xpath.startswith('/'):
-                    xpath = '.' + xpath
-                elif xpath and not xpath.startswith('./'):
-                    xpath = './' + xpath
-
-                def apply_specials(element):
-                    if special is None:
-                        return element
-                    if special == '@':
-                        return element.attrib
-                    if special.startswith('@'):
-                        return try_call(element.attrib.get, args=(special[1:],))
-                    if special == 'text()':
-                        return element.text
-                    raise SyntaxError('apply_specials is missing case for {0!r}'.format(special))
-
-                if xpath:
-                    result = list(map(apply_specials, compat_etree_iterfind(obj, xpath)))
-                else:
-                    result = apply_specials(obj)
-
         return branching, result if branching else (result,)
 
     def lazy_last(iterable):
@@ -6493,18 +6456,17 @@ def traverse_obj(obj, *paths, **kwargs):
 
         key = None
         for last, key in lazy_last(variadic(path, (str, bytes, dict, set))):
+            if _is_user_input and isinstance(key, str):
+                if key == ':':
+                    key = Ellipsis
+                elif ':' in key:
+                    key = slice(*map(int_or_none, key.split(':')))
+                elif int_or_none(key) is not None:
+                    key = int(key)
+
             if not casesense and isinstance(key, str):
                 key = compat_casefold(key)
 
-            if key in (any, all):
-                has_branched = False
-                filtered_objs = (obj for obj in objs if obj not in (None, {}))
-                if key is any:
-                    objs = (next(filtered_objs, None),)
-                else:
-                    objs = (list(filtered_objs),)
-                continue
-
             if __debug__ and callable(key):
                 # Verify function signature
                 _try_bind_args(key, None, None)
@@ -6543,9 +6505,9 @@ def traverse_obj(obj, *paths, **kwargs):
     return None if default is NO_DEFAULT else default
 
 
-def T(*x):
+def T(x):
-    """ For use in yt-dl instead of {type, ...} or set((type, ...)) """
+    """ For use in yt-dl instead of {type} or set((type,)) """
-    return set(x)
+    return set((x,))
 
 
 def get_first(obj, keys, **kwargs):