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mirror of https://github.com/ytdl-org/youtube-dl.git synced 2024-12-23 00:16:48 +00:00

[jsinterp] Fix and improve loose and strict equality operations

* reimplement loose equality according to MDN (eg, 1 == "1")
* improve strict equality (eg, "abc" === "abc" but 'abc' is not 'abc')
* add tests for above
This commit is contained in:
dirkf 2024-12-12 00:00:32 +00:00
parent 7e93935dda
commit 527c137e4e
2 changed files with 101 additions and 14 deletions

View File

@ -1,4 +1,5 @@
#!/usr/bin/env python #!/usr/bin/env python
# coding: utf-8
from __future__ import unicode_literals from __future__ import unicode_literals
@ -11,7 +12,7 @@ sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
import math import math
import re import re
from youtube_dl.compat import compat_str from youtube_dl.compat import compat_str as str
from youtube_dl.jsinterp import JS_Undefined, JSInterpreter from youtube_dl.jsinterp import JS_Undefined, JSInterpreter
NaN = object() NaN = object()
@ -19,7 +20,7 @@ NaN = object()
class TestJSInterpreter(unittest.TestCase): class TestJSInterpreter(unittest.TestCase):
def _test(self, jsi_or_code, expected, func='f', args=()): def _test(self, jsi_or_code, expected, func='f', args=()):
if isinstance(jsi_or_code, compat_str): if isinstance(jsi_or_code, str):
jsi_or_code = JSInterpreter(jsi_or_code) jsi_or_code = JSInterpreter(jsi_or_code)
got = jsi_or_code.call_function(func, *args) got = jsi_or_code.call_function(func, *args)
if expected is NaN: if expected is NaN:
@ -89,7 +90,35 @@ class TestJSInterpreter(unittest.TestCase):
self._test('function f(){return 19 & 21;}', 17) self._test('function f(){return 19 & 21;}', 17)
self._test('function f(){return 11 >> 2;}', 2) self._test('function f(){return 11 >> 2;}', 2)
self._test('function f(){return []? 2+3: 4;}', 5) self._test('function f(){return []? 2+3: 4;}', 5)
# equality
self._test('function f(){return 1 == 1}', True)
self._test('function f(){return 1 == 1.0}', True)
self._test('function f(){return 1 == "1"}', True)
self._test('function f(){return 1 == 2}', False) self._test('function f(){return 1 == 2}', False)
self._test('function f(){return 1 != "1"}', False)
self._test('function f(){return 1 != 2}', True)
self._test('function f(){var x = {a: 1}; var y = x; return x == y}', True)
self._test('function f(){var x = {a: 1}; return x == {a: 1}}', False)
self._test('function f(){return NaN == NaN}', False)
self._test('function f(){return null == undefined}', True)
self._test('function f(){return "spam, eggs" == "spam, eggs"}', True)
# strict equality
self._test('function f(){return 1 === 1}', True)
self._test('function f(){return 1 === 1.0}', True)
self._test('function f(){return 1 === "1"}', False)
self._test('function f(){return 1 === 2}', False)
self._test('function f(){var x = {a: 1}; var y = x; return x === y}', True)
self._test('function f(){var x = {a: 1}; return x === {a: 1}}', False)
self._test('function f(){return NaN === NaN}', False)
self._test('function f(){return null === undefined}', False)
self._test('function f(){return null === null}', True)
self._test('function f(){return undefined === undefined}', True)
self._test('function f(){return "uninterned" === "uninterned"}', True)
self._test('function f(){return 1 === 1}', True)
self._test('function f(){return 1 === "1"}', False)
self._test('function f(){return 1 !== 1}', False)
self._test('function f(){return 1 !== "1"}', True)
# expressions
self._test('function f(){return 0 && 1 || 2;}', 2) self._test('function f(){return 0 && 1 || 2;}', 2)
self._test('function f(){return 0 ?? 42;}', 0) self._test('function f(){return 0 ?? 42;}', 0)
self._test('function f(){return "life, the universe and everything" < 42;}', False) self._test('function f(){return "life, the universe and everything" < 42;}', False)

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@ -1,3 +1,4 @@
# coding: utf-8
from __future__ import unicode_literals from __future__ import unicode_literals
import itertools import itertools
@ -64,6 +65,10 @@ _NaN = float('nan')
_Infinity = float('inf') _Infinity = float('inf')
class JS_Undefined(object):
pass
def _js_bit_op(op): def _js_bit_op(op):
def zeroise(x): def zeroise(x):
@ -107,12 +112,69 @@ def _js_exp(a, b):
return (a or 0) ** b return (a or 0) ** b
def _js_eq_op(op): def _js_to_primitive(v):
return (
','.join(map(_js_toString, v)) if isinstance(v, list)
else '[object Object]' if isinstance(v, dict)
else compat_str(v) if not isinstance(v, (
compat_numeric_types, compat_basestring, bool))
else v
)
def _js_toString(v):
return (
'undefined' if v is JS_Undefined
else 'Infinity' if v == _Infinity
else 'NaN' if v is _NaN
else 'null' if v is None
else compat_str(v) if isinstance(v, compat_numeric_types)
else _js_to_primitive(v))
_nullish = frozenset((None, JS_Undefined))
def _js_eq(a, b):
# NaN != any
if _NaN in (a, b):
return False
# Object is Object
if isinstance(a, type(b)) and isinstance(b, (dict, list)):
return operator.is_(a, b)
# general case
if a == b:
return True
# null == undefined
a_b = set((a, b))
if a_b & _nullish:
return a_b <= _nullish
a, b = _js_to_primitive(a), _js_to_primitive(b)
if not isinstance(a, compat_basestring):
a, b = b, a
# Number to String: convert the string to a number
# Conversion failure results in ... false
if isinstance(a, compat_basestring):
return float_or_none(a) == b
return a == b
def _js_neq(a, b):
return not _js_eq(a, b)
def _js_id_op(op):
@wraps_op(op) @wraps_op(op)
def wrapped(a, b): def wrapped(a, b):
if set((a, b)) <= set((None, JS_Undefined)): if _NaN in (a, b):
return op(a, a) return op(_NaN, None)
if not isinstance(a, (compat_basestring, compat_numeric_types)):
a, b = b, a
# strings are === if ==
# why 'a' is not 'a': https://stackoverflow.com/a/1504848
if isinstance(a, (compat_basestring, compat_numeric_types)):
return a == b if op(0, 0) else a != b
return op(a, b) return op(a, b)
return wrapped return wrapped
@ -187,10 +249,10 @@ _OPERATORS = (
) )
_COMP_OPERATORS = ( _COMP_OPERATORS = (
('===', operator.is_), ('===', _js_id_op(operator.is_)),
('!==', operator.is_not), ('!==', _js_id_op(operator.is_not)),
('==', _js_eq_op(operator.eq)), ('==', _js_eq),
('!=', _js_eq_op(operator.ne)), ('!=', _js_neq),
('<=', _js_comp_op(operator.le)), ('<=', _js_comp_op(operator.le)),
('>=', _js_comp_op(operator.ge)), ('>=', _js_comp_op(operator.ge)),
('<', _js_comp_op(operator.lt)), ('<', _js_comp_op(operator.lt)),
@ -222,10 +284,6 @@ _MATCHING_PARENS = dict(zip(*zip('()', '{}', '[]')))
_QUOTES = '\'"/' _QUOTES = '\'"/'
class JS_Undefined(object):
pass
class JS_Break(ExtractorError): class JS_Break(ExtractorError):
def __init__(self): def __init__(self):
ExtractorError.__init__(self, 'Invalid break') ExtractorError.__init__(self, 'Invalid break')