commit: 27ed77aabba8c9eb08d66f34092b1bfcc22c482e
parent c4b19a88169fa76c5eb665d274e7270a0fe452c4
Author: Andrei Lebedev <lebdron@gmail.com>
Date: Thu, 3 Nov 2022 11:09:37 +0100
[utils] Backport traverse_obj (etc) from yt-dlp (#31156)
* Backport traverse_obj and closely related function from yt-dlp (code by pukkandan)
* Backport LazyList, variadic(), try_call (code by pukkandan)
* Recast using yt-dlp's newer traverse_obj() implementation and tests (code by grub4k)
* Add tests for Unicode case folding support matching Py3.5+ (requires f102e3d)
* Improve/add tests for variadic, try_call, join_nonempty
Co-authored-by: dirkf <fieldhouse@gmx.net>
Diffstat:
| M | test/test_utils.py | 323 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
| M | youtube_dl/utils.py | 339 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
2 files changed, 662 insertions(+), 0 deletions(-)
diff --git a/test/test_utils.py b/test/test_utils.py
@@ -12,7 +12,9 @@ sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
# Various small unit tests
import io
+import itertools
import json
+import re
import xml.etree.ElementTree
from youtube_dl.utils import (
@@ -40,11 +42,14 @@ 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,
is_html,
+ join_nonempty,
js_to_json,
+ LazyList,
limit_length,
merge_dicts,
mimetype2ext,
@@ -79,6 +84,8 @@ from youtube_dl.utils import (
strip_or_none,
subtitles_filename,
timeconvert,
+ traverse_obj,
+ try_call,
unescapeHTML,
unified_strdate,
unified_timestamp,
@@ -92,6 +99,7 @@ from youtube_dl.utils import (
urlencode_postdata,
urshift,
update_url_query,
+ variadic,
version_tuple,
xpath_with_ns,
xpath_element,
@@ -112,12 +120,18 @@ from youtube_dl.compat import (
compat_getenv,
compat_os_name,
compat_setenv,
+ compat_str,
compat_urlparse,
compat_parse_qs,
)
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)
@@ -1478,6 +1492,315 @@ Line 1
self.assertEqual(clean_podcast_url('https://www.podtrac.com/pts/redirect.mp3/chtbl.com/track/5899E/traffic.megaphone.fm/HSW7835899191.mp3'), 'https://traffic.megaphone.fm/HSW7835899191.mp3')
self.assertEqual(clean_podcast_url('https://play.podtrac.com/npr-344098539/edge1.pod.npr.org/anon.npr-podcasts/podcast/npr/waitwait/2020/10/20201003_waitwait_wwdtmpodcast201003-015621a5-f035-4eca-a9a1-7c118d90bc3c.mp3'), 'https://edge1.pod.npr.org/anon.npr-podcasts/podcast/npr/waitwait/2020/10/20201003_waitwait_wwdtmpodcast201003-015621a5-f035-4eca-a9a1-7c118d90bc3c.mp3')
+ def test_LazyList(self):
+ it = list(range(10))
+
+ self.assertEqual(list(LazyList(it)), it)
+ self.assertEqual(LazyList(it).exhaust(), it)
+ self.assertEqual(LazyList(it)[5], it[5])
+
+ self.assertEqual(LazyList(it)[5:], it[5:])
+ self.assertEqual(LazyList(it)[:5], it[:5])
+ self.assertEqual(LazyList(it)[::2], it[::2])
+ self.assertEqual(LazyList(it)[1::2], it[1::2])
+ self.assertEqual(LazyList(it)[5::-1], it[5::-1])
+ self.assertEqual(LazyList(it)[6:2:-2], it[6:2:-2])
+ self.assertEqual(LazyList(it)[::-1], it[::-1])
+
+ self.assertTrue(LazyList(it))
+ self.assertFalse(LazyList(range(0)))
+ self.assertEqual(len(LazyList(it)), len(it))
+ self.assertEqual(repr(LazyList(it)), repr(it))
+ self.assertEqual(compat_str(LazyList(it)), compat_str(it))
+
+ self.assertEqual(list(LazyList(it, reverse=True)), it[::-1])
+ self.assertEqual(list(reversed(LazyList(it))[::-1]), it)
+ self.assertEqual(list(reversed(LazyList(it))[1:3:7]), it[::-1][1:3:7])
+
+ def test_LazyList_laziness(self):
+
+ def test(ll, idx, val, cache):
+ self.assertEqual(ll[idx], val)
+ self.assertEqual(ll._cache, list(cache))
+
+ ll = LazyList(range(10))
+ test(ll, 0, 0, range(1))
+ test(ll, 5, 5, range(6))
+ test(ll, -3, 7, range(10))
+
+ ll = LazyList(range(10), reverse=True)
+ test(ll, -1, 0, range(1))
+ test(ll, 3, 6, range(10))
+
+ ll = LazyList(itertools.count())
+ test(ll, 10, 10, range(11))
+ ll = reversed(ll)
+ test(ll, -15, 14, range(15))
+
+ def test_try_call(self):
+ def total(*x, **kwargs):
+ return sum(x) + sum(kwargs.values())
+
+ self.assertEqual(try_call(None), None,
+ msg='not a fn should give None')
+ self.assertEqual(try_call(lambda: 1), 1,
+ msg='int fn with no expected_type should give int')
+ self.assertEqual(try_call(lambda: 1, expected_type=int), 1,
+ msg='int fn with expected_type int should give int')
+ self.assertEqual(try_call(lambda: 1, expected_type=dict), None,
+ msg='int fn with wrong expected_type should give None')
+ self.assertEqual(try_call(total, args=(0, 1, 0, ), expected_type=int), 1,
+ msg='fn should accept arglist')
+ self.assertEqual(try_call(total, kwargs={'a': 0, 'b': 1, 'c': 0}, expected_type=int), 1,
+ msg='fn should accept kwargs')
+ self.assertEqual(try_call(lambda: 1, expected_type=dict), None,
+ msg='int fn with no expected_type should give None')
+ self.assertEqual(try_call(lambda x: {}, total, args=(42, ), expected_type=int), 42,
+ msg='expect first int result with expected_type int')
+
+ def test_variadic(self):
+ self.assertEqual(variadic(None), (None, ))
+ self.assertEqual(variadic('spam'), ('spam', ))
+ self.assertEqual(variadic('spam', allowed_types=dict), 'spam')
+
+ def test_traverse_obj(self):
+ _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': {},
+ }
+
+ # 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 is not None),
+ msg='`...` should give all values except `None`')
+ 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')), range(4),
+ msg='`...` query result should be flattened')
+
+ # 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], compat_str)), {'str'},
+ msg='exceptions in the query function should be caught')
+
+ # 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 dict key')
+ self.assertEqual(traverse_obj(_TEST_DATA, {0: 'fail'}, default=Ellipsis), {0: Ellipsis},
+ msg='do not remove `None` values if `default`')
+ self.assertEqual(traverse_obj(_TEST_DATA, {0: 'dict'}), {0: {}},
+ msg='do not remove empty values when dict key')
+ self.assertEqual(traverse_obj(_TEST_DATA, {0: 'dict'}, default=Ellipsis), {0: {}},
+ msg='do not remove empty values when dict key and a default')
+ self.assertEqual(traverse_obj(_TEST_DATA, {0: ('dict', Ellipsis)}), {0: []},
+ msg='if branch in dict key not successful, return `[]`')
+
+ # 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`')
+
+ # Testing expected_type behavior
+ _EXPECTED_TYPE_DATA = {'str': 'str', 'int': 0}
+ self.assertEqual(traverse_obj(_EXPECTED_TYPE_DATA, 'str', expected_type=compat_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: compat_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=compat_str), ['str'],
+ msg='eliminate items that expected_type fails on')
+
+ # 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), list('str'),
+ msg='`...` branching into string should result in list')
+ self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, ('str', (0, 2)),
+ _traverse_string=True), ['s', 'r'],
+ msg='branching into string should result in list')
+ self.assertEqual(traverse_obj(_TRAVERSE_STRING_DATA, ('str', lambda _, x: x),
+ _traverse_string=True), list('str'),
+ msg='function branching into string should result in list')
+
+ # 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`')
+
+ 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(
+ 'a', 'b', 'c', 'd',
+ from_dict={'a': 'c', 'c': [], 'b': 'd', 'd': None}), 'c-d')
+
if __name__ == '__main__':
unittest.main()
diff --git a/youtube_dl/utils.py b/youtube_dl/utils.py
@@ -43,6 +43,7 @@ from .compat import (
compat_HTTPError,
compat_basestring,
compat_chr,
+ compat_collections_abc,
compat_cookiejar,
compat_ctypes_WINFUNCTYPE,
compat_etree_fromstring,
@@ -1685,6 +1686,7 @@ USER_AGENTS = {
NO_DEFAULT = object()
+IDENTITY = lambda x: x
ENGLISH_MONTH_NAMES = [
'January', 'February', 'March', 'April', 'May', 'June',
@@ -3867,6 +3869,105 @@ def detect_exe_version(output, version_re=None, unrecognized='present'):
return unrecognized
+class LazyList(compat_collections_abc.Sequence):
+ """Lazy immutable list from an iterable
+ Note that slices of a LazyList are lists and not LazyList"""
+
+ class IndexError(IndexError):
+ def __init__(self, cause=None):
+ if cause:
+ # reproduce `raise from`
+ self.__cause__ = cause
+ super(IndexError, self).__init__()
+
+ def __init__(self, iterable, **kwargs):
+ # kwarg-only
+ reverse = kwargs.get('reverse', False)
+ _cache = kwargs.get('_cache')
+
+ self._iterable = iter(iterable)
+ self._cache = [] if _cache is None else _cache
+ self._reversed = reverse
+
+ def __iter__(self):
+ if self._reversed:
+ # We need to consume the entire iterable to iterate in reverse
+ for item in self.exhaust():
+ yield item
+ return
+ for item in self._cache:
+ yield item
+ for item in self._iterable:
+ self._cache.append(item)
+ yield item
+
+ def _exhaust(self):
+ self._cache.extend(self._iterable)
+ self._iterable = [] # Discard the emptied iterable to make it pickle-able
+ return self._cache
+
+ def exhaust(self):
+ """Evaluate the entire iterable"""
+ return self._exhaust()[::-1 if self._reversed else 1]
+
+ @staticmethod
+ def _reverse_index(x):
+ return None if x is None else ~x
+
+ def __getitem__(self, idx):
+ if isinstance(idx, slice):
+ if self._reversed:
+ idx = slice(self._reverse_index(idx.start), self._reverse_index(idx.stop), -(idx.step or 1))
+ start, stop, step = idx.start, idx.stop, idx.step or 1
+ elif isinstance(idx, int):
+ if self._reversed:
+ idx = self._reverse_index(idx)
+ start, stop, step = idx, idx, 0
+ else:
+ raise TypeError('indices must be integers or slices')
+ if ((start or 0) < 0 or (stop or 0) < 0
+ or (start is None and step < 0)
+ or (stop is None and step > 0)):
+ # We need to consume the entire iterable to be able to slice from the end
+ # Obviously, never use this with infinite iterables
+ self._exhaust()
+ try:
+ return self._cache[idx]
+ except IndexError as e:
+ raise self.IndexError(e)
+ n = max(start or 0, stop or 0) - len(self._cache) + 1
+ if n > 0:
+ self._cache.extend(itertools.islice(self._iterable, n))
+ try:
+ return self._cache[idx]
+ except IndexError as e:
+ raise self.IndexError(e)
+
+ def __bool__(self):
+ try:
+ self[-1] if self._reversed else self[0]
+ except self.IndexError:
+ return False
+ return True
+
+ def __len__(self):
+ self._exhaust()
+ return len(self._cache)
+
+ def __reversed__(self):
+ return type(self)(self._iterable, reverse=not self._reversed, _cache=self._cache)
+
+ def __copy__(self):
+ return type(self)(self._iterable, reverse=self._reversed, _cache=self._cache)
+
+ def __repr__(self):
+ # repr and str should mimic a list. So we exhaust the iterable
+ return repr(self.exhaust())
+
+ def __str__(self):
+ return repr(self.exhaust())
+
+
class PagedList(object):
def __len__(self):
# This is only useful for tests
@@ -4092,6 +4193,10 @@ def multipart_encode(data, boundary=None):
return out, content_type
+def variadic(x, allowed_types=(compat_str, bytes, dict)):
+ return x if isinstance(x, compat_collections_abc.Iterable) and not isinstance(x, allowed_types) else (x,)
+
+
def dict_get(d, key_or_keys, default=None, skip_false_values=True):
if isinstance(key_or_keys, (list, tuple)):
for key in key_or_keys:
@@ -4102,6 +4207,23 @@ def dict_get(d, key_or_keys, default=None, skip_false_values=True):
return d.get(key_or_keys, default)
+def try_call(*funcs, **kwargs):
+
+ # parameter defaults
+ expected_type = kwargs.get('expected_type')
+ fargs = kwargs.get('args', [])
+ fkwargs = kwargs.get('kwargs', {})
+
+ for f in funcs:
+ try:
+ val = f(*fargs, **fkwargs)
+ except (AttributeError, KeyError, TypeError, IndexError, ZeroDivisionError):
+ pass
+ else:
+ if expected_type is None or isinstance(val, expected_type):
+ return val
+
+
def try_get(src, getter, expected_type=None):
if not isinstance(getter, (list, tuple)):
getter = [getter]
@@ -5835,3 +5957,220 @@ def clean_podcast_url(url):
st\.fm # https://podsights.com/docs/
)/e
)/''', '', url)
+
+
+def traverse_obj(obj, *paths, **kwargs):
+ """
+ Safely traverse nested `dict`s and `Sequence`s
+
+ >>> obj = [{}, {"key": "value"}]
+ >>> traverse_obj(obj, (1, "key"))
+ "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`, `Sequence` and `re.Match`.
+ A value of None is treated as the absence of a value.
+
+ The paths will be wrapped in `variadic`, so that `'key'` is conveniently the same as `('key', )`.
+
+ The keys in the path can be one of:
+ - `None`: Return the current object.
+ - `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.
+ - `tuple`/`list`: Branch out and return a list of all matching values.
+ Read as: `[traverse_obj(obj, branch) for branch in branches]`.
+ - `function`: Branch out and return values filtered by the function.
+ Read as: `[value for key, value in obj if function(key, value)]`.
+ For `Sequence`s, `key` is the index of the value.
+ - `dict` Transform the current object and return a matching dict.
+ Read as: `{key: traverse_obj(obj, path) for key, path in dct.items()}`.
+
+ `tuple`, `list`, and `dict` all support nested paths and branches.
+
+ @params paths Paths which to traverse by.
+ Keyword arguments:
+ @param default Value to return if the paths do not match.
+ @param expected_type If a `type`, only accept final values of this type.
+ If any other callable, try to call the function on each result.
+ @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 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.
+
+
+ @returns The result of the object traversal.
+ If successful, `get_all=True`, and the path branches at least once,
+ then a list of results is returned instead.
+ A list is always returned if the last path branches and no `default` is given.
+ """
+
+ # parameter defaults
+ default = kwargs.get('default', NO_DEFAULT)
+ 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
+ str = compat_str
+
+ is_sequence = lambda x: isinstance(x, compat_collections_abc.Sequence) and not isinstance(x, (str, bytes))
+ # stand-in until compat_re_Match is added
+ compat_re_Match = type(re.match('a', 'a'))
+ # stand-in until casefold.py is added
+ try:
+ ''.casefold()
+ compat_casefold = lambda s: s.casefold()
+ except AttributeError:
+ compat_casefold = lambda s: s.lower()
+ casefold = lambda k: compat_casefold(k) if isinstance(k, str) else k
+
+ if isinstance(expected_type, type):
+ type_test = lambda val: val if isinstance(val, expected_type) else None
+ else:
+ type_test = lambda val: try_call(expected_type or IDENTITY, args=(val,))
+
+ def from_iterable(iterables):
+ # chain.from_iterable(['ABC', 'DEF']) --> A B C D E F
+ for it in iterables:
+ for item in it:
+ yield item
+
+ def apply_key(key, obj):
+ if obj is None:
+ return
+
+ elif key is None:
+ yield obj
+
+ elif isinstance(key, (list, tuple)):
+ for branch in key:
+ _, result = apply_path(obj, branch)
+ for item in result:
+ yield item
+
+ elif key is Ellipsis:
+ result = []
+ if isinstance(obj, compat_collections_abc.Mapping):
+ result = obj.values()
+ elif is_sequence(obj):
+ result = obj
+ elif isinstance(obj, compat_re_Match):
+ result = obj.groups()
+ elif _traverse_string:
+ result = str(obj)
+ for item in result:
+ yield item
+
+ elif callable(key):
+ if is_sequence(obj):
+ iter_obj = enumerate(obj)
+ elif isinstance(obj, compat_collections_abc.Mapping):
+ iter_obj = obj.items()
+ elif isinstance(obj, compat_re_Match):
+ iter_obj = enumerate(itertools.chain([obj.group()], obj.groups()))
+ elif _traverse_string:
+ iter_obj = enumerate(str(obj))
+ else:
+ return
+ for item in (v for k, v in iter_obj if try_call(key, args=(k, v))):
+ yield item
+
+ elif isinstance(key, dict):
+ iter_obj = ((k, _traverse_obj(obj, v)) for k, v in key.items())
+ yield dict((k, v if v is not None else default) for k, v in iter_obj
+ if v is not None or default is not NO_DEFAULT)
+
+ elif isinstance(obj, compat_collections_abc.Mapping):
+ yield (obj.get(key) if casesense or (key in obj)
+ else next((v for k, v in obj.items() if casefold(k) == key), None))
+
+ elif isinstance(obj, compat_re_Match):
+ if isinstance(key, int) or casesense:
+ try:
+ yield obj.group(key)
+ return
+ except IndexError:
+ pass
+ if not isinstance(key, str):
+ return
+
+ yield next((v for k, v in obj.groupdict().items() if casefold(k) == key), None)
+
+ else:
+ if _is_user_input:
+ key = (int_or_none(key) if ':' not in key
+ else slice(*map(int_or_none, key.split(':'))))
+
+ if not isinstance(key, (int, slice)):
+ return
+
+ if not is_sequence(obj):
+ if not _traverse_string:
+ return
+ obj = str(obj)
+
+ try:
+ yield obj[key]
+ except IndexError:
+ pass
+
+ def apply_path(start_obj, path):
+ objs = (start_obj,)
+ has_branched = False
+
+ for key in variadic(path):
+ if _is_user_input and key == ':':
+ key = Ellipsis
+
+ if not casesense and isinstance(key, str):
+ key = compat_casefold(key)
+
+ if key is Ellipsis or isinstance(key, (list, tuple)) or callable(key):
+ has_branched = True
+
+ key_func = functools.partial(apply_key, key)
+ objs = from_iterable(map(key_func, objs))
+
+ return has_branched, objs
+
+ def _traverse_obj(obj, path, use_list=True):
+ has_branched, results = apply_path(obj, path)
+ results = LazyList(x for x in map(type_test, results) if x is not None)
+
+ if get_all and has_branched:
+ return results.exhaust() if results or use_list else None
+
+ return results[0] if results else None
+
+ for index, path in enumerate(paths, 1):
+ use_list = default is NO_DEFAULT and index == len(paths)
+ result = _traverse_obj(obj, path, use_list)
+ if result is not None:
+ return result
+
+ return None if default is NO_DEFAULT else default
+
+
+def get_first(obj, keys, **kwargs):
+ return traverse_obj(obj, (Ellipsis,) + tuple(variadic(keys)), get_all=False, **kwargs)
+
+
+def join_nonempty(*values, **kwargs):
+
+ # parameter defaults
+ delim = kwargs.get('delim', '-')
+ from_dict = kwargs.get('from_dict')
+
+ if from_dict is not None:
+ values = (traverse_obj(from_dict, variadic(v)) for v in values)
+ return delim.join(map(compat_str, filter(None, values)))
