Repository: yt-dlp/yt-dlp
File: yt_dlp/extractor/vk.py (Python)

Code before:
            })

        entries.extend(self.url_result(urljoin(url, entry), VKIE) for entry in set(re.findall(
            r'<a[^>]+href=(?:["\'])(/video(?:-?[\d_]+)[^"\']*)',
            get_element_html_by_id('wl_post_body', webpage))))

        return self.playlist_result(
            entries, post_id, join_nonempty(uploader, f'Wall post {post_id}', delim=' - '),
            clean_html(get_element_by_class('wall_post_text', webpage)))


class VKPlayBaseIE(InfoExtractor):
    _RESOLUTIONS = {
        'tiny': '256x144',
        'lowest': '426x240',
        'low': '640x360',
        'medium': '852x480',
        'high': '1280x720',
        'full_hd': '1920x1080',
        'quad_hd': '2560x1440',
    }

    def _extract_initial_state(self, url, video_id):
        webpage = self._download_webpage(url, video_id)
        return self._search_json(
            r'<script[^>]+\bid="initial-state"[^>]*>', webpage, 'initial state', video_id, fatal=False)

    def _extract_formats(self, stream_info, video_id):
        formats = []
        for stream in traverse_obj(stream_info, (
                'data', 0, 'playerUrls', lambda _, v: url_or_none(v['url']) and v['type'])):
            url = stream['url']
            format_id = str_or_none(stream['type'])
            if format_id in ('hls', 'live_hls', 'live_playback_hls') or '.m3u8' in url:
                formats.extend(self._extract_m3u8_formats(url, video_id, m3u8_id=format_id, fatal=False))
            elif format_id in ('dash'):
                formats.extend(self._extract_mpd_formats(url, video_id, mpd_id=format_id, fatal=False))
            elif format_id in ('live_dash', 'live_playback_dash'):
                self.to_screen(f'Skipping unsupported format "{format_id}"')
            else:
                formats.append({
                    'url': url,
                    'ext': 'mp4',
                    'format_id': format_id,
                    **parse_resolution(self._RESOLUTIONS.get(format_id)),
                })
        return formats

    def _extract_common_meta(self, stream_info):
        return traverse_obj(stream_info, {
            'id': ('id', {str_or_none}),

Review comment (refactor):
Since this is fatal now, we can reduce some more code duplication
```suggestion
    def _extract_initial_state(self, url, video_id, path):
        webpage = self._download_webpage(url, video_id)
        initial_state = traverse_obj(self._search_json(
            r'<script[^>]+\bid="initial-state"[^>]*>', webpage, 'initial state', video_id),
            path, expected_type=dict)
        if not initial_state:
            raise ExtractorError('Unable to extract initial state')
        return initial_state
```

Code after:
            })

        entries.extend(self.url_result(urljoin(url, entry), VKIE) for entry in set(re.findall(
            r'<a[^>]+href=(?:["\'])(/video(?:-?[\d_]+)[^"\']*)',
            get_element_html_by_id('wl_post_body', webpage))))

        return self.playlist_result(
            entries, post_id, join_nonempty(uploader, f'Wall post {post_id}', delim=' - '),
            clean_html(get_element_by_class('wall_post_text', webpage)))


class VKPlayBaseIE(InfoExtractor):
    _RESOLUTIONS = {
        'tiny': '256x144',
        'lowest': '426x240',
        'low': '640x360',
        'medium': '852x480',
        'high': '1280x720',
        'full_hd': '1920x1080',
        'quad_hd': '2560x1440',
    }

    def _extract_from_initial_state(self, url, video_id, path):
        webpage = self._download_webpage(url, video_id)
        video_info = traverse_obj(self._search_json(
            r'<script[^>]+\bid="initial-state"[^>]*>', webpage, 'initial state', video_id),
            path, expected_type=dict)
        if not video_info:
            raise ExtractorError('Unable to extract video info from html inline initial state')
        return video_info

    def _extract_formats(self, stream_info, video_id):
        formats = []
        for stream in traverse_obj(stream_info, (
                'data', 0, 'playerUrls', lambda _, v: url_or_none(v['url']) and v['type'])):
            url = stream['url']
            format_id = str_or_none(stream['type'])
            if format_id in ('hls', 'live_hls', 'live_playback_hls') or '.m3u8' in url:
                formats.extend(self._extract_m3u8_formats(url, video_id, m3u8_id=format_id, fatal=False))
            elif format_id == 'dash':
                formats.extend(self._extract_mpd_formats(url, video_id, mpd_id=format_id, fatal=False))
            elif format_id in ('live_dash', 'live_playback_dash'):
                self.write_debug(f'Not extracting unsupported format "{format_id}"')
            else:
                formats.append({
                    'url': url,
                    'ext': 'mp4',
                    'format_id': format_id,
                    **parse_resolution(self._RESOLUTIONS.get(format_id)),
                })
        return formats