ExtractorError: Unsupported JS expression u'['

[thompcha]

Download fails when running the following:
youtube-dl --verbose https://www.youtube.com/watch?v=bAZM6ghdwUI

[debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: [u'--verbose', u'https://www.youtube.com/watch?v=bAZM6ghdwUI']
[debug] Encodings: locale UTF-8, fs utf-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2020.06.16.1
[debug] Python version 2.7.14 (CPython) - Darwin-19.5.0-x86_64-i386-64bit
[debug] exe versions: avconv present, avprobe present, ffmpeg 4.3, ffprobe 4.3, rtmpdump 2.4
[debug] Proxy map: {}
[youtube] bAZM6ghdwUI: Downloading webpage
[youtube] {18} signature length 104, html5 player f82a8c37
[youtube] bAZM6ghdwUI: Downloading player https://www.youtube.com/s/player/f82a8c37/player_ias.vflset/en_US/base.js
ERROR: Signature extraction failed: Traceback (most recent call last):
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 1426, in _decrypt_signature
video_id, player_url, s
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 1338, in _extract_signature_function
cache_res = res(test_string)
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 1402, in
return lambda s: initial_function([s])
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 258, in resf
res, abort = self.interpret_statement(stmt, local_vars)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 56, in interpret_statement
v = self.interpret_expression(expr, local_vars, allow_recursion)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 92, in interpret_expression
m.group('expr'), local_vars, allow_recursion - 1)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 189, in interpret_expression
m.group('x'), local_vars, allow_recursion - 1)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 56, in interpret_statement
v = self.interpret_expression(expr, local_vars, allow_recursion)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 211, in interpret_expression
raise ExtractorError('Unsupported JS expression %r' % expr)
ExtractorError: Unsupported JS expression u'['; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; type youtube-dl -U to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.
(caused by ExtractorError(u"Unsupported JS expression u'['; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; type youtube-dl -U to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.",)); please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; type youtube-dl -U to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.
Traceback (most recent call last):
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 1426, in _decrypt_signature
video_id, player_url, s
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 1338, in _extract_signature_function
cache_res = res(test_string)
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 1402, in
return lambda s: initial_function([s])
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 258, in resf
res, abort = self.interpret_statement(stmt, local_vars)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 56, in interpret_statement
v = self.interpret_expression(expr, local_vars, allow_recursion)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 92, in interpret_expression
m.group('expr'), local_vars, allow_recursion - 1)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 189, in interpret_expression
m.group('x'), local_vars, allow_recursion - 1)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 56, in interpret_statement
v = self.interpret_expression(expr, local_vars, allow_recursion)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 211, in interpret_expression
raise ExtractorError('Unsupported JS expression %r' % expr)
ExtractorError: Unsupported JS expression u'['; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; type youtube-dl -U to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.
Traceback (most recent call last):
File "/usr/local/bin/youtube-dl/youtube_dl/YoutubeDL.py", line 797, in extract_info
ie_result = ie.extract(url)
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/common.py", line 530, in extract
ie_result = self._real_extract(url)
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 2107, in _real_extract
encrypted_sig, video_id, player_url, age_gate)
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 1436, in _decrypt_signature
'Signature extraction failed: ' + tb, cause=e)
ExtractorError: Signature extraction failed: Traceback (most recent call last):
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 1426, in _decrypt_signature
video_id, player_url, s
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 1338, in _extract_signature_function
cache_res = res(test_string)
File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 1402, in
return lambda s: initial_function([s])
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 258, in resf
res, abort = self.interpret_statement(stmt, local_vars)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 56, in interpret_statement
v = self.interpret_expression(expr, local_vars, allow_recursion)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 92, in interpret_expression
m.group('expr'), local_vars, allow_recursion - 1)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 189, in interpret_expression
m.group('x'), local_vars, allow_recursion - 1)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 56, in interpret_statement
v = self.interpret_expression(expr, local_vars, allow_recursion)
File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 211, in interpret_expression
raise ExtractorError('Unsupported JS expression %r' % expr)
ExtractorError: Unsupported JS expression u'['; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; type youtube-dl -U to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.
(caused by ExtractorError(u"Unsupported JS expression u'['; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; type youtube-dl -U to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.",)); please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; type youtube-dl -U to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.

[love124356]

See this answer first.
You can try to uninstall youtube-dl and reinstall it.

[koshikas]

See this answer first.
You can try to uninstall youtube-dl and reinstall it.

thanks, getting the latest youtube-dl indeed fixed it. turns out arch packages are out of date ATM

[shriDeveloper]

@love124356 Tried the step but no help. Still the same issue.

Here's the error dump:

[koshikas]

@love124356 Tried the step but no help. Still the same issue.

Here's the error dump:

you will run into it unless you are running the latest version 2020.07.28
if you are running packaged version you most probably are not using the latest version. if so uninstall it and manually install it as per; https://rg3.github.io/youtube-dl/download.html