Merge 20691a11e6 into c5098961b0

Now also succeeds with player b12cc44b

test/test_jsinterp.py

@@ -425,6 +425,34 @@ class TestJSInterpreter(unittest.TestCase):
             self._test(jsi, [''], args=['', '-'])
             self._test(jsi, [], args=['', ''])
 
+    def test_slice(self):
+        self._test('function f(){return [0, 1, 2, 3, 4, 5, 6, 7, 8].slice()}', [0, 1, 2, 3, 4, 5, 6, 7, 8])
+        self._test('function f(){return [0, 1, 2, 3, 4, 5, 6, 7, 8].slice(0)}', [0, 1, 2, 3, 4, 5, 6, 7, 8])
+        self._test('function f(){return [0, 1, 2, 3, 4, 5, 6, 7, 8].slice(5)}', [5, 6, 7, 8])
+        self._test('function f(){return [0, 1, 2, 3, 4, 5, 6, 7, 8].slice(99)}', [])
+        self._test('function f(){return [0, 1, 2, 3, 4, 5, 6, 7, 8].slice(-2)}', [7, 8])
+        self._test('function f(){return [0, 1, 2, 3, 4, 5, 6, 7, 8].slice(-99)}', [0, 1, 2, 3, 4, 5, 6, 7, 8])
+        self._test('function f(){return [0, 1, 2, 3, 4, 5, 6, 7, 8].slice(0, 0)}', [])
+        self._test('function f(){return [0, 1, 2, 3, 4, 5, 6, 7, 8].slice(1, 0)}', [])
+        self._test('function f(){return [0, 1, 2, 3, 4, 5, 6, 7, 8].slice(0, 1)}', [0])
+        self._test('function f(){return [0, 1, 2, 3, 4, 5, 6, 7, 8].slice(3, 6)}', [3, 4, 5])
+        self._test('function f(){return [0, 1, 2, 3, 4, 5, 6, 7, 8].slice(1, -1)}', [1, 2, 3, 4, 5, 6, 7])
+        self._test('function f(){return [0, 1, 2, 3, 4, 5, 6, 7, 8].slice(-1, 1)}', [])
+        self._test('function f(){return [0, 1, 2, 3, 4, 5, 6, 7, 8].slice(-3, -1)}', [6, 7])
+        self._test('function f(){return "012345678".slice()}', '012345678')
+        self._test('function f(){return "012345678".slice(0)}', '012345678')
+        self._test('function f(){return "012345678".slice(5)}', '5678')
+        self._test('function f(){return "012345678".slice(99)}', '')
+        self._test('function f(){return "012345678".slice(-2)}', '78')
+        self._test('function f(){return "012345678".slice(-99)}', '012345678')
+        self._test('function f(){return "012345678".slice(0, 0)}', '')
+        self._test('function f(){return "012345678".slice(1, 0)}', '')
+        self._test('function f(){return "012345678".slice(0, 1)}', '0')
+        self._test('function f(){return "012345678".slice(3, 6)}', '345')
+        self._test('function f(){return "012345678".slice(1, -1)}', '1234567')
+        self._test('function f(){return "012345678".slice(-1, 1)}', '')
+        self._test('function f(){return "012345678".slice(-3, -1)}', '67')
+
 
 if __name__ == '__main__':
     unittest.main()

test/test_youtube_signature.py

@@ -174,6 +174,14 @@ _NSIG_TESTS = [
         'https://www.youtube.com/s/player/5604538d/player_ias.vflset/en_US/base.js',
         '7X-he4jjvMx7BCX', 'sViSydX8IHtdWA',
     ),
+    (
+        'https://www.youtube.com/s/player/20dfca59/player_ias.vflset/en_US/base.js',
+        '-fLCxedkAk4LUTK2', 'O8kfRq1y1eyHGw',
+    ),
+    (
+        'https://www.youtube.com/s/player/b12cc44b/player_ias.vflset/en_US/base.js',
+        'keLa5R2U00sR9SQK', 'N1OGyujjEwMnLw',
+    ),
 ]
 
 

youtube_dl/extractor/extractors.py

@@ -1065,7 +1065,7 @@ from .rtl2 import (
 )
 from .rtp import RTPIE
 from .rts import RTSIE
-from .rtve import RTVEALaCartaIE, RTVELiveIE, RTVEInfantilIE, RTVELiveIE, RTVETelevisionIE
+from .rtve import RTVEPlayIE, RTVEInfantilIE, RTVELiveIE, RTVETelevisionIE
 from .rtvnh import RTVNHIE
 from .rtvs import RTVSIE
 from .ruhd import RUHDIE

youtube_dl/extractor/rtve.py

@@ -12,30 +12,30 @@ from ..compat import (
     compat_struct_unpack,
 )
 from ..utils import (
+    clean_html,
     determine_ext,
     ExtractorError,
     float_or_none,
     qualities,
-    remove_end,
-    remove_start,
     std_headers,
 )
 
 _bytes_to_chr = (lambda x: x) if sys.version_info[0] == 2 else (lambda x: map(chr, x))
 
 
-class RTVEALaCartaIE(InfoExtractor):
-    IE_NAME = 'rtve.es:alacarta'
-    IE_DESC = 'RTVE a la carta'
-    _VALID_URL = r'https?://(?:www\.)?rtve\.es/(m/)?(alacarta/videos|filmoteca)/[^/]+/[^/]+/(?P<id>\d+)'
+class RTVEPlayIE(InfoExtractor):
+    IE_NAME = 'rtve.es:play'
+    IE_DESC = 'RTVE Play'
+    _VALID_URL = r'https?://(?:www\.)?rtve\.es/(?P<kind>(?:playz?|(?:m/)?alacarta)/(?:audios|videos)|filmoteca)/[^/]+/[^/]+/(?P<id>\d+)'
 
     _TESTS = [{
         'url': 'http://www.rtve.es/alacarta/videos/balonmano/o-swiss-cup-masculina-final-espana-suecia/2491869/',
-        'md5': '1d49b7e1ca7a7502c56a4bf1b60f1b43',
+        'md5': '2c70aacf8a415d1b4e7fcc0525951162',
         'info_dict': {
             'id': '2491869',
             'ext': 'mp4',
-            'title': 'Balonmano - Swiss Cup masculina. Final: España-Suecia',
+            'title': 'Final de la Swiss Cup masculina: España-Suecia',
+            'description': 'Swiss Cup masculina, Final: España-Suecia.',
             'duration': 5024.566,
             'series': 'Balonmano',
         },
@@ -47,6 +47,7 @@ class RTVEALaCartaIE(InfoExtractor):
             'id': '1694255',
             'ext': 'mp4',
             'title': 're:^24H LIVE [0-9]{4}-[0-9]{2}-[0-9]{2} [0-9]{2}:[0-9]{2}$',
+            'description': '24H LIVE',
             'is_live': True,
         },
         'params': {
@@ -54,11 +55,12 @@ class RTVEALaCartaIE(InfoExtractor):
         },
     }, {
         'url': 'http://www.rtve.es/alacarta/videos/servir-y-proteger/servir-proteger-capitulo-104/4236788/',
-        'md5': 'd850f3c8731ea53952ebab489cf81cbf',
+        'md5': '30b8827cba25f39d1af5a7c482cc8ac5',
         'info_dict': {
             'id': '4236788',
             'ext': 'mp4',
-            'title': 'Servir y proteger - Capítulo 104',
+            'title': 'Capítulo 104',
+            'description': 'md5:caae29ae04291875e611dd667fe84641',
             'duration': 3222.0,
         },
         'expected_warnings': ['Failed to download MPD manifest', 'Failed to download m3u8 information'],
@@ -68,6 +70,17 @@ class RTVEALaCartaIE(InfoExtractor):
     }, {
         'url': 'http://www.rtve.es/filmoteca/no-do/not-1-introduccion-primer-noticiario-espanol/1465256/',
         'only_matching': True,
+    }, {
+        'url': 'http://www.rtve.es/alacarta/audios/a-hombros-de-gigantes/palabra-ingeniero-codigos-informaticos-27-04-21/5889192/',
+        'md5': 'ae06d27bff945c4e87a50f89f6ce48ce',
+        'info_dict': {
+            'id': '5889192',
+            'ext': 'mp3',
+            'title': 'Códigos informáticos',
+            'description': 'md5:72b0d7c1ca20fd327bdfff7ac0171afb',
+            'thumbnail': r're:https?://.+/1598856591583.jpg',
+            'duration': 349.440,
+        },
     }]
 
     def _real_initialize(self):
@@ -86,8 +99,12 @@ class RTVEALaCartaIE(InfoExtractor):
                 break
             data = encrypted_data.read(length)
             if chunk_type == b'tEXt':
-                alphabet_data, text = data.split(b'\0')
-                quality, url_data = text.split(b'%%')
+                alphabet_data, text = data.replace(b'\0', b'').split(b'#')
+                components = text.split(b'%%')
+                if len(components) < 2:
+                    components.insert(0, b'')
+                quality, url_data = components
+
                 alphabet = []
                 e = 0
                 d = 0
@@ -120,7 +137,7 @@ class RTVEALaCartaIE(InfoExtractor):
 
     def _extract_png_formats(self, video_id):
         png = self._download_webpage(
-            'http://www.rtve.es/ztnr/movil/thumbnail/%s/videos/%s.png' % (self._manager, video_id),
+            'http://ztnr.rtve.es/ztnr/movil/thumbnail/%s/videos/%s.png' % (self._manager, video_id),
             video_id, 'Downloading url information', query={'q': 'v2'})
         q = qualities(['Media', 'Alta', 'HQ', 'HD_READY', 'HD_FULL'])
         formats = []
@@ -143,11 +160,16 @@ class RTVEALaCartaIE(InfoExtractor):
         return formats
 
     def _real_extract(self, url):
-        video_id = self._match_id(url)
+        groups = re.match(self._VALID_URL, url).groupdict()
+        is_audio = groups.get('kind') == 'play/audios'
+        return self._real_extract_from_id(groups['id'], is_audio)
+
+    def _real_extract_from_id(self, video_id, is_audio=False):
+        kind = 'audios' if is_audio else 'videos'
         info = self._download_json(
-            'http://www.rtve.es/api/videos/%s/config/alacarta_videos.json' % video_id,
+            'http://www.rtve.es/api/%s/%s.json' % (kind, video_id),
             video_id)['page']['items'][0]
-        if info['state'] == 'DESPU':
+        if (info.get('pubState') or {}).get('code') == 'DESPU':
             raise ExtractorError('The video is no longer available', expected=True)
         title = info['title'].strip()
         formats = self._extract_png_formats(video_id)
@@ -157,17 +179,19 @@ class RTVEALaCartaIE(InfoExtractor):
         if sbt_file:
             subtitles = self.extract_subtitles(video_id, sbt_file)
 
-        is_live = info.get('live') is True
+        is_live = info.get('consumption') == 'live'
 
         return {
             'id': video_id,
             'title': self._live_title(title) if is_live else title,
             'formats': formats,
-            'thumbnail': info.get('image'),
+            'url': info.get('htmlUrl'),
+            'description': clean_html(info.get('description')),
+            'thumbnail': info.get('thumbnail'),
             'subtitles': subtitles,
             'duration': float_or_none(info.get('duration'), 1000),
             'is_live': is_live,
-            'series': info.get('programTitle'),
+            'series': (info.get('programInfo') or {}).get('title'),
         }
 
     def _get_subtitles(self, video_id, sub_file):
@@ -179,36 +203,60 @@ class RTVEALaCartaIE(InfoExtractor):
             for s in subs)
 
 
-class RTVEInfantilIE(RTVEALaCartaIE):
+class RTVEInfantilIE(RTVEPlayIE):
     IE_NAME = 'rtve.es:infantil'
     IE_DESC = 'RTVE infantil'
     _VALID_URL = r'https?://(?:www\.)?rtve\.es/infantil/serie/[^/]+/video/[^/]+/(?P<id>[0-9]+)/'
 
     _TESTS = [{
-        'url': 'http://www.rtve.es/infantil/serie/cleo/video/maneras-vivir/3040283/',
-        'md5': '5747454717aedf9f9fdf212d1bcfc48d',
+        'url': 'https://www.rtve.es/infantil/serie/dino-ranch/video/pequeno-gran-ayudante/6693248/',
+        'md5': '06d3f57eec593ad93fe9dcf079fbd940',
         'info_dict': {
-            'id': '3040283',
+            'id': '6693248',
             'ext': 'mp4',
-            'title': 'Maneras de vivir',
-            'thumbnail': r're:https?://.+/1426182947956\.JPG',
-            'duration': 357.958,
+            'title': 'Un pequeño gran ayudante',
+            'description': 'md5:144ca351e31f9ee99a637ab9fc2787d5',
+            'thumbnail': r're:https?://.+/1663318364501\.jpg',
+            'duration': 691.44,
         },
         'expected_warnings': ['Failed to download MPD manifest', 'Failed to download m3u8 information'],
     }]
 
 
-class RTVELiveIE(RTVEALaCartaIE):
+class RTVELiveIE(RTVEPlayIE):
     IE_NAME = 'rtve.es:live'
     IE_DESC = 'RTVE.es live streams'
-    _VALID_URL = r'https?://(?:www\.)?rtve\.es/directo/(?P<id>[a-zA-Z0-9-]+)'
+    _VALID_URL = r'https?://(?:www\.)?rtve\.es/play/videos/directo/(?P<id>.+)'
 
     _TESTS = [{
-        'url': 'http://www.rtve.es/directo/la-1/',
+        'url': 'https://www.rtve.es/play/videos/directo/la-1/',
         'info_dict': {
-            'id': 'la-1',
+            'id': '1688877',
             'ext': 'mp4',
             'title': 're:^La 1 [0-9]{4}-[0-9]{2}-[0-9]{2} [0-9]{2}:[0-9]{2}$',
+            'description': 'La 1',
+        },
+        'params': {
+            'skip_download': 'live stream',
+        }
+    }, {
+        'url': 'https://www.rtve.es/play/videos/directo/canales-lineales/la-1/',
+        'info_dict': {
+            'id': '1688877',
+            'ext': 'mp4',
+            'title': 're:^La 1 [0-9]{4}-[0-9]{2}-[0-9]{2} [0-9]{2}:[0-9]{2}$',
+            'description': 'La 1',
+        },
+        'params': {
+            'skip_download': 'live stream',
+        }
+    }, {
+        'url': 'https://www.rtve.es/play/videos/directo/canales-lineales/capilla-ardiente-isabel-westminster/10886/',
+        'info_dict': {
+            'id': '1938028',
+            'ext': 'mp4',
+            'title': 're:^Mas24 - 1 [0-9]{4}-[0-9]{2}-[0-9]{2} [0-9]{2}:[0-9]{2}$',
+            'description': 'Mas24 - 1',
         },
         'params': {
             'skip_download': 'live stream',
@@ -216,53 +264,77 @@ class RTVELiveIE(RTVEALaCartaIE):
     }]
 
     def _real_extract(self, url):
-        mobj = re.match(self._VALID_URL, url)
-        video_id = mobj.group('id')
-
-        webpage = self._download_webpage(url, video_id)
-        title = remove_end(self._og_search_title(webpage), ' en directo en RTVE.es')
-        title = remove_start(title, 'Estoy viendo ')
-
-        vidplayer_id = self._search_regex(
-            (r'playerId=player([0-9]+)',
-             r'class=["\'].*?\blive_mod\b.*?["\'][^>]+data-assetid=["\'](\d+)',
-             r'data-id=["\'](\d+)'),
+        webpage = self._download_webpage(url, self._match_id(url))
+        asset_id = self._search_regex(
+            r'class=["\'].*?\bvideoPlayer\b.*?["\'][^>]+data-setup=[^>]+?(?:"|&quot;)idAsset(?:"|&quot;)\s*:\s*(?:"|&quot;)(\d+)(?:"|&quot;)',
             webpage, 'internal video ID')
-
-        return {
-            'id': video_id,
-            'title': self._live_title(title),
-            'formats': self._extract_png_formats(vidplayer_id),
-            'is_live': True,
-        }
+        return self._real_extract_from_id(asset_id)
 
 
 class RTVETelevisionIE(InfoExtractor):
     IE_NAME = 'rtve.es:television'
-    _VALID_URL = r'https?://(?:www\.)?rtve\.es/television/[^/]+/[^/]+/(?P<id>\d+).shtml'
+    # https://www.rtve.es/SECTION/YYYYMMDD/CONTENT_SLUG/CONTENT_ID.shtml
+    _VALID_URL = r'https?://(?:www\.)?rtve\.es/[^/]+/\d{8}/[^/]+/(?P<id>\d+)\.shtml'
 
-    _TEST = {
-        'url': 'http://www.rtve.es/television/20160628/revolucion-del-movil/1364141.shtml',
+    _TESTS = [{
+        'url': 'https://www.rtve.es/television/20220916/destacados-festival-san-sebastian-rtve-play/2395620.shtml',
         'info_dict': {
-            'id': '3069778',
+            'id': '6668919',
             'ext': 'mp4',
-            'title': 'Documentos TV - La revolución del móvil',
-            'duration': 3496.948,
+            'title': 'Las películas del Festival de San Sebastián en RTVE Play',
+            'description': 'El\xa0Festival de San Sebastián vuelve a llenarse de artistas. Y en su honor,\xa0RTVE Play\xa0destacará cada viernes una\xa0película galardonada\xa0con la\xa0Concha de Oro\xa0en su catálogo.',
+            'duration': 20.048,
         },
         'params': {
             'skip_download': True,
         },
-    }
+    }, {
+        'url': 'https://www.rtve.es/noticias/20220917/penelope-cruz-san-sebastian-premio-nacional/2402565.shtml',
+        'info_dict': {
+            'id': '6694087',
+            'ext': 'mp4',
+            'title': 'Penélope Cruz recoge el Premio Nacional de Cinematografía: "No dejen nunca de proteger nuestro cine"',
+            'description': 'md5:eda9e6baa78dbbbcc7708c0cc8150a91',
+            'duration': 388.2,
+        },
+        'params': {
+            'skip_download': True,
+        },
+    }, {
+        'url': 'https://www.rtve.es/deportes/20220917/motogp-bagnaia-pole-marquez-decimotercero-motorland-aragon/2402566.shtml',
+        'info_dict': {
+            'id': '6694142',
+            'ext': 'mp4',
+            'title': "Bagnaia logra su quinta 'pole' del año y Márquez partirá decimotercero",
+            'description': 'md5:07e2ccb983a046cb42f896cce225f0a7',
+            'duration': 153.44,
+        },
+        'params': {
+            'skip_download': True,
+        },
+    }, {
+        'url': 'https://www.rtve.es/playz/20220807/covaleda-fest-final/2394809.shtml',
+        'info_dict': {
+            'id': '6665408',
+            'ext': 'mp4',
+            'title': 'Covaleda Fest (Soria) - Día 3 con Marc Seguí y Paranoid 1966',
+            'description': 'Festivales Playz viaja a Covaleda, Soria, para contarte todo lo que sucede en el Covaleda Fest. Entrevistas, challenges a los artistas, juegos... Khan, Adriana Jiménez y María García no dejarán pasar ni una. ¡No te lo pierdas!',
+            'duration': 12009.92,
+        },
+        'params': {
+            'skip_download': True,
+        },
+    }]
 
     def _real_extract(self, url):
         page_id = self._match_id(url)
         webpage = self._download_webpage(url, page_id)
 
         alacarta_url = self._search_regex(
-            r'data-location="alacarta_videos"[^<]+url&quot;:&quot;(http://www\.rtve\.es/alacarta.+?)&',
+            r'data-location="alacarta_videos"[^<]+url&quot;:&quot;(https?://www\.rtve\.es/play.+?)&',
             webpage, 'alacarta url', default=None)
         if alacarta_url is None:
             raise ExtractorError(
                 'The webpage doesn\'t contain any video', expected=True)
 
-        return self.url_result(alacarta_url, ie=RTVEALaCartaIE.ie_key())
+        return self.url_result(alacarta_url, ie=RTVEPlayIE.ie_key())

youtube_dl/extractor/youtube.py

@@ -1659,17 +1659,46 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
     def _extract_n_function_name(self, jscode):
         func_name, idx = self._search_regex(
             # new: (b=String.fromCharCode(110),c=a.get(b))&&c=nfunc[idx](c)
-            # or:  (b="nn"[+a.D],c=a.get(b))&&(c=nfunc[idx](c)s
-            # old: .get("n"))&&(b=nfunc[idx](b)
-            # older: .get("n"))&&(b=nfunc(b)
+            # or:  (b="nn"[+a.D],c=a.get(b))&&(c=nfunc[idx](c)
+            # or:  (PL(a),b=a.j.n||null)&&(b=nfunc[idx](b)
+            # or:  (b="nn"[+a.D],vL(a),c=a.j[b]||null)&&(c=narray[idx](c),a.set(b,c),narray.length||nfunc("")
+            # old: (b=a.get("n"))&&(b=nfunc[idx](b)(?P<c>[a-z])\s*=\s*[a-z]\s*
+            # older: (b=a.get("n"))&&(b=nfunc(b)
             r'''(?x)
-                (?:\(\s*(?P<b>[a-z])\s*=\s*(?:
-                    String\s*\.\s*fromCharCode\s*\(\s*110\s*\)|
-                    "n+"\[\s*\+?s*[\w$.]+\s*]
-                )\s*,(?P<c>[a-z])\s*=\s*[a-z]\s*)?
-                \.\s*get\s*\(\s*(?(b)(?P=b)|"n{1,2}")(?:\s*\)){2}\s*&&\s*\(\s*(?(c)(?P=c)|b)\s*=\s*
-                (?P<nfunc>[a-zA-Z_$][\w$]*)(?:\s*\[(?P<idx>\d+)\])?\s*\(\s*[\w$]+\s*\)
-            ''', jscode, 'Initial JS player n function name', group=('nfunc', 'idx'))
+                \((?:[\w$()\s]+,)*?\s*      # (
+                (?P<b>[a-z])\s*=\s*         # b=
+                (?:
+                    (?:                     # expect ,c=a.get(b) (etc)
+                        String\s*\.\s*fromCharCode\s*\(\s*110\s*\)|
+                        "n+"\[\s*\+?s*[\w$.]+\s*]
+                    )\s*(?:,[\w$()\s]+(?=,))*|
+                       (?P<old>[\w$]+)      # a (old[er])
+                   )\s*
+                   (?(old)
+                                            # b.get("n")
+                       (?:\.\s*[\w$]+\s*|\[\s*[\w$]+\s*]\s*)*?
+                       (?:\.\s*n|\[\s*"n"\s*]|\.\s*get\s*\(\s*"n"\s*\))
+                       |                    # ,c=a.get(b)
+                       ,\s*(?P<c>[a-z])\s*=\s*[a-z]\s*
+                       (?:\.\s*[\w$]+\s*|\[\s*[\w$]+\s*]\s*)*?
+                       (?:\[\s*(?P=b)\s*]|\.\s*get\s*\(\s*(?P=b)\s*\))
+                   )
+                                            # interstitial junk
+                   \s*(?:\|\|\s*null\s*)?(?:\)\s*)?&&\s*(?:\(\s*)?
+               (?(c)(?P=c)|(?P=b))\s*=\s*   # [c|b]=
+                                            # nfunc|nfunc[idx]
+                   (?P<nfunc>[a-zA-Z_$][\w$]*)(?:\s*\[(?P<idx>\d+)\])?\s*\(\s*[\w$]+\s*\)
+            ''', jscode, 'Initial JS player n function name', group=('nfunc', 'idx'),
+            default=(None, None))
+        # thx bashonly: yt-dlp/yt-dlp/pull/10611
+        if not func_name:
+            self.report_warning('Falling back to generic n function search')
+            return self._search_regex(
+                r'''(?xs)
+                    (?:(?<=[^\w$])|^)       # instead of \b, which ignores $
+                    (?P<name>(?!\d)[a-zA-Z\d_$]+)\s*=\s*function\((?!\d)[a-zA-Z\d_$]+\)
+                    \s*\{(?:(?!};).)+?["']enhanced_except_
+                ''', jscode, 'Initial JS player n function name', group='name')
         if not idx:
             return func_name
 

youtube_dl/jsinterp.py

@@ -925,9 +925,16 @@ class JSInterpreter(object):
                     obj.reverse()
                     return obj
                 elif member == 'slice':
-                    assertion(isinstance(obj, list), 'must be applied on a list')
-                    assertion(len(argvals) == 1, 'takes exactly one argument')
-                    return obj[argvals[0]:]
+                    assertion(isinstance(obj, (list, compat_str)), 'must be applied on a list or string')
+                    # From [1]:
+                    # .slice() - like [:]
+                    # .slice(n) - like [n:] (not [slice(n)]
+                    # .slice(m, n) - like [m:n] or [slice(m, n)]
+                    # [1] https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/slice
+                    assertion(len(argvals) <= 2, 'takes between 0 and 2 arguments')
+                    if len(argvals) < 2:
+                        argvals += (None,)
+                    return obj[slice(*argvals)]
                 elif member == 'splice':
                     assertion(isinstance(obj, list), 'must be applied on a list')
                     assertion(argvals, 'takes one or more arguments')