commit: f47fdb9564d3ca1c0fa70ed6031148ec908fdc7b
parent b6dff4073d469cceadb099c00ccbf3bd6fc515a6
Author: dirkf <fieldhouse@gmx.net>
Date: Thu, 6 Jul 2023 15:46:22 +0100
[utils] Add {expected_type} and Iterable support to traverse_obj()
Diffstat:
| M | test/test_utils.py | 153 | ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--------------- |
| M | youtube_dl/utils.py | 213 | ++++++++++++++++++++++++++++++++++++++++++++++++++++-------------------------- |
2 files changed, 266 insertions(+), 100 deletions(-)
diff --git a/test/test_utils.py b/test/test_utils.py
@@ -79,10 +79,12 @@ from youtube_dl.utils import (
rot47,
shell_quote,
smuggle_url,
+ str_or_none,
str_to_int,
strip_jsonp,
strip_or_none,
subtitles_filename,
+ T,
timeconvert,
traverse_obj,
try_call,
@@ -1566,6 +1568,7 @@ Line 1
self.assertEqual(variadic('spam', allowed_types=[dict]), 'spam')
def test_traverse_obj(self):
+ str = compat_str
_TEST_DATA = {
100: 100,
1.2: 1.2,
@@ -1598,8 +1601,8 @@ Line 1
# 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`')
+ (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')),
@@ -1607,13 +1610,51 @@ Line 1
msg='nested `...` queries should work')
self.assertCountEqual(traverse_obj(_TEST_DATA, (Ellipsis, Ellipsis, 'index')), 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], compat_str)), ('str',),
- msg='exceptions in the query function should be caught')
+ self.assertCountEqual(traverse_obj(_TEST_DATA, lambda _, x: isinstance(x[0], str)), {'str'},
+ msg='exceptions in the query function should be catched')
+ 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, {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',
@@ -1659,15 +1700,23 @@ Line 1
{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')
+ msg='remove `None` values when top level dict key fails')
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 `[]`')
+ 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 `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': []}
@@ -1691,20 +1740,55 @@ Line 1
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=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')
+ 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, {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]}
@@ -1749,14 +1833,23 @@ Line 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')
+ _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 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')
+ 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))}
@@ -1793,6 +1886,8 @@ Line 1
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')
diff --git a/youtube_dl/utils.py b/youtube_dl/utils.py
@@ -16,6 +16,7 @@ import email.header
import errno
import functools
import gzip
+import inspect
import io
import itertools
import json
@@ -3881,7 +3882,7 @@ def detect_exe_version(output, version_re=None, unrecognized='present'):
return unrecognized
-class LazyList(compat_collections_abc.Sequence):
+class LazyList(compat_collections_abc.Iterable):
"""Lazy immutable list from an iterable
Note that slices of a LazyList are lists and not LazyList"""
@@ -4223,10 +4224,16 @@ def multipart_encode(data, boundary=None):
return out, content_type
-def variadic(x, allowed_types=(compat_str, bytes, dict)):
- if not isinstance(allowed_types, tuple) and isinstance(allowed_types, compat_collections_abc.Iterable):
+def is_iterable_like(x, allowed_types=compat_collections_abc.Iterable, blocked_types=NO_DEFAULT):
+ if blocked_types is NO_DEFAULT:
+ blocked_types = (compat_str, bytes, compat_collections_abc.Mapping)
+ return isinstance(x, allowed_types) and not isinstance(x, blocked_types)
+
+
+def variadic(x, allowed_types=NO_DEFAULT):
+ if isinstance(allowed_types, compat_collections_abc.Iterable):
allowed_types = tuple(allowed_types)
- return x if isinstance(x, compat_collections_abc.Iterable) and not isinstance(x, allowed_types) else (x,)
+ return x if is_iterable_like(x, blocked_types=allowed_types) else (x,)
def dict_get(d, key_or_keys, default=None, skip_false_values=True):
@@ -5993,7 +6000,7 @@ def clean_podcast_url(url):
def traverse_obj(obj, *paths, **kwargs):
"""
- Safely traverse nested `dict`s and `Sequence`s
+ Safely traverse nested `dict`s and `Iterable`s
>>> obj = [{}, {"key": "value"}]
>>> traverse_obj(obj, (1, "key"))
@@ -6001,14 +6008,17 @@ def traverse_obj(obj, *paths, **kwargs):
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.
+ Supported values for traversal are `Mapping`, `Iterable` and `re.Match`.
+ 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', )`.
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)`.
+ - `set`: Requires the only item in the set to be a type or function,
+ like `{type}`/`{func}`. If a `type`, returns only values
+ of this type. If a function, returns `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.
- `tuple`/`list`: Branch out and return a list of all matching values.
@@ -6016,6 +6026,9 @@ def traverse_obj(obj, *paths, **kwargs):
- `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.
+ 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.
Read as: `{key: traverse_obj(obj, path) for key, path in dct.items()}`.
@@ -6024,8 +6037,12 @@ def traverse_obj(obj, *paths, **kwargs):
@params paths Paths which to traverse by.
Keyword arguments:
@param default Value to return if the paths do not match.
+ If the last key in the path is a `dict`, it will apply to each value inside
+ the dict instead, depth first. Try to avoid if using nested `dict` keys.
@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.
+ If the last key in the path is a `dict`, it will apply to each value inside
+ the dict instead, recursively. This does respect branching paths.
@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.
@@ -6036,12 +6053,15 @@ def traverse_obj(obj, *paths, **kwargs):
@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.
+ The return value of that path will be a string instead,
+ not respecting any further branching.
@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.
+ If a path ends on a `dict` that result will always be a `dict`.
"""
# parameter defaults
@@ -6055,7 +6075,6 @@ def traverse_obj(obj, *paths, **kwargs):
# instant compat
str = compat_str
- is_sequence = lambda x: isinstance(x, compat_collections_abc.Sequence) and not isinstance(x, (str, bytes))
casefold = lambda k: compat_casefold(k) if isinstance(k, str) else k
if isinstance(expected_type, type):
@@ -6063,128 +6082,180 @@ def traverse_obj(obj, *paths, **kwargs):
else:
type_test = lambda val: try_call(expected_type or IDENTITY, args=(val,))
+ def lookup_or_none(v, k, getter=None):
+ 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
for it in iterables:
for item in it:
yield item
- def apply_key(key, obj):
- if obj is None:
- return
+ def apply_key(key, obj, is_last):
+ branching = False
+
+ if obj is None and _traverse_string:
+ if key is Ellipsis or callable(key) or isinstance(key, slice):
+ branching = True
+ result = ()
+ else:
+ result = None
elif key is None:
- yield obj
+ result = obj
+
+ elif isinstance(key, set):
+ assert len(key) == 1, 'Set should only be used to wrap a single item'
+ item = next(iter(key))
+ if isinstance(item, type):
+ result = obj if isinstance(obj, item) else None
+ else:
+ result = try_call(item, args=(obj,))
elif isinstance(key, (list, tuple)):
- for branch in key:
- _, result = apply_path(obj, branch)
- for item in result:
- yield item
+ branching = True
+ result = from_iterable(
+ apply_path(obj, branch, is_last)[0] for branch in key)
elif key is Ellipsis:
- result = []
+ branching = True
if isinstance(obj, compat_collections_abc.Mapping):
result = obj.values()
- elif is_sequence(obj):
+ elif is_iterable_like(obj):
result = obj
elif isinstance(obj, compat_re_Match):
result = obj.groups()
elif _traverse_string:
+ branching = False
result = str(obj)
- for item in result:
- yield item
+ else:
+ result = ()
elif callable(key):
- if is_sequence(obj):
- iter_obj = enumerate(obj)
- elif isinstance(obj, compat_collections_abc.Mapping):
+ branching = True
+ if isinstance(obj, compat_collections_abc.Mapping):
iter_obj = obj.items()
+ elif is_iterable_like(obj):
+ iter_obj = enumerate(obj)
elif isinstance(obj, compat_re_Match):
- iter_obj = enumerate(itertools.chain([obj.group()], obj.groups()))
+ iter_obj = itertools.chain(
+ enumerate(itertools.chain((obj.group(),), obj.groups())),
+ obj.groupdict().items())
elif _traverse_string:
+ branching = False
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
+ iter_obj = ()
+
+ result = (v for k, v in iter_obj if try_call(key, args=(k, v)))
+ if not branching: # string traversal
+ result = ''.join(result)
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)
+ iter_obj = ((k, _traverse_obj(obj, v, False, is_last)) for k, v in key.items())
+ result = 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) or None
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))
+ 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))
elif isinstance(obj, compat_re_Match):
+ result = None
if isinstance(key, int) or casesense:
- try:
- yield obj.group(key)
- return
- except IndexError:
- pass
- if not isinstance(key, str):
- return
+ result = lookup_or_none(obj, key, getter=compat_re_Match.group)
- yield next((v for k, v in obj.groupdict().items() if casefold(k) == key), None)
+ elif isinstance(key, str):
+ result = 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(':'))))
+ result = None
+ if isinstance(key, (int, slice)):
+ 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)
+
+ return branching, result if branching else (result,)
+
+ def lazy_last(iterable):
+ iterator = iter(iterable)
+ prev = next(iterator, NO_DEFAULT)
+ if prev is NO_DEFAULT:
+ return
- if not isinstance(key, (int, slice)):
- return
+ for item in iterator:
+ yield False, prev
+ prev = item
- if not is_sequence(obj):
- if not _traverse_string:
- return
- obj = str(obj)
+ yield True, prev
- try:
- yield obj[key]
- except IndexError:
- pass
-
- def apply_path(start_obj, path):
+ def apply_path(start_obj, path, test_type):
objs = (start_obj,)
has_branched = False
- for key in variadic(path):
- if _is_user_input and key == ':':
- key = Ellipsis
+ 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 is Ellipsis or isinstance(key, (list, tuple)) or callable(key):
- has_branched = True
+ if __debug__ and callable(key):
+ # Verify function signature
+ inspect.getcallargs(key, None, None)
+
+ new_objs = []
+ for obj in objs:
+ branching, results = apply_key(key, obj, last)
+ has_branched |= branching
+ new_objs.append(results)
+
+ objs = from_iterable(new_objs)
- key_func = functools.partial(apply_key, key)
- objs = from_iterable(map(key_func, objs))
+ if test_type and not isinstance(key, (dict, list, tuple)):
+ objs = map(type_test, objs)
- return has_branched, objs
+ return objs, has_branched, isinstance(key, dict)
- 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)
+ def _traverse_obj(obj, path, allow_empty, test_type):
+ results, has_branched, is_dict = apply_path(obj, path, test_type)
+ results = LazyList(x for x in results if x not in (None, {}))
if get_all and has_branched:
- return results.exhaust() if results or use_list else None
+ if results:
+ return results.exhaust()
+ if allow_empty:
+ return [] if default is NO_DEFAULT else default
+ return None
- return results[0] if results else None
+ return results[0] if results else {} if allow_empty and is_dict 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)
+ result = _traverse_obj(obj, path, index == len(paths), True)
if result is not None:
return result
return None if default is NO_DEFAULT else default
+def T(x):
+ """ For use in yt-dl instead of {type} or set((type,)) """
+ return set((x,))
+
+
def get_first(obj, keys, **kwargs):
return traverse_obj(obj, (Ellipsis,) + tuple(variadic(keys)), get_all=False, **kwargs)
