[jsinterp] Fix bug in operator precedence

* from 164b03c486
* added tests

test/test_jsinterp.py

@@ -192,6 +192,31 @@ class TestJSInterpreter(unittest.TestCase):
         ''')
         self.assertEqual(jsi.call_function('x'), 10)
 
+    def test_catch(self):
+        jsi = JSInterpreter('''
+        function x() { try{throw 10} catch(e){return 5} }
+        ''')
+        self.assertEqual(jsi.call_function('x'), 5)
+
+    @unittest.expectedFailure
+    def test_finally(self):
+        jsi = JSInterpreter('''
+        function x() { try{throw 10} finally {return 42} }
+        ''')
+        self.assertEqual(jsi.call_function('x'), 42)
+        jsi = JSInterpreter('''
+        function x() { try{throw 10} catch(e){return 5} finally {return 42} }
+        ''')
+        self.assertEqual(jsi.call_function('x'), 42)
+
+    def test_nested_try(self):
+        jsi = JSInterpreter('''
+        function x() {try {
+            try{throw 10} finally {throw 42} 
+            } catch(e){return 5} }
+        ''')
+        self.assertEqual(jsi.call_function('x'), 5)
+
     def test_for_loop_continue(self):
         jsi = JSInterpreter('''
         function x() { a=0; for (i=0; i-10; i++) { continue; a++ } return a }

test/test_youtube_signature.py

@@ -111,6 +111,10 @@ _NSIG_TESTS = [
         'https://www.youtube.com/s/player/1f7d5369/player_ias.vflset/en_US/base.js',
         'batNX7sYqIJdkJ', 'IhOkL_zxbkOZBw',
     ),
+    (
+        'https://www.youtube.com/s/player/dc0c6770/player_ias.vflset/en_US/base.js',
+        '5EHDMgYLV6HPGk_Mu-kk', 'n9lUJLHbxUI0GQ',
+    ),
 ]
 
 

youtube_dl/extractor/youtube.py

@@ -1500,7 +1500,8 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
         return lambda s: jsi.extract_function_from_code(*func_code)([s])
 
     def _n_descramble(self, n_param, player_url, video_id):
-        """Compute the response to YT's "n" parameter challenge
+        """Compute the response to YT's "n" parameter challenge,
+           or None
 
         Args:
         n_param     -- challenge string that is the value of the
@@ -1518,7 +1519,10 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
             if player_id not in self._player_cache:
                 self._player_cache[player_id] = self._extract_n_function(video_id, player_url)
             func = self._player_cache[player_id]
-            self._player_cache[sig_id] = func(n_param)
+            ret = func(n_param)
+            if ret.startswith('enhanced_except_'):
+                raise ExtractorError('Unhandled exception in decode')
+            self._player_cache[sig_id] = ret
             if self._downloader.params.get('verbose', False):
                 self._downloader.to_screen('[debug] [%s] %s' % (self.IE_NAME, 'Decrypted nsig {0} => {1}'.format(n_param, self._player_cache[sig_id])))
             return self._player_cache[sig_id]
@@ -1539,10 +1543,12 @@ class YoutubeIE(YoutubeBaseInfoExtractor):
                 continue
             n_param = n_param[-1]
             n_response = self._n_descramble(n_param, player_url, video_id)
-            if n_response:
-                qs['n'] = [n_response]
-                fmt['url'] = compat_urlparse.urlunparse(
-                    parsed_fmt_url._replace(query=compat_urllib_parse_urlencode(qs, True)))
+            if n_response is None:
+                # give up if descrambling failed
+                break
+            qs['n'] = [n_response]
+            fmt['url'] = compat_urlparse.urlunparse(
+                parsed_fmt_url._replace(query=compat_urllib_parse_urlencode(qs, True)))
 
     def _mark_watched(self, video_id, player_response):
         playback_url = url_or_none(try_get(

youtube_dl/jsinterp.py

@@ -5,6 +5,7 @@ import json
 import math
 import operator
 import re
+from collections import Counter
 
 from .utils import (
     error_to_compat_str,
@@ -108,8 +109,8 @@ _OPERATORS = (
 
 _COMP_OPERATORS = (
     ('===', operator.is_),
-    ('==', _js_eq_op(operator.eq)),
     ('!==', operator.is_not),
+    ('==', _js_eq_op(operator.eq)),
     ('!=', _js_eq_op(operator.ne)),
     ('<=', _js_comp_op(operator.le)),
     ('>=', _js_comp_op(operator.ge)),
@@ -241,7 +242,9 @@ class JSInterpreter(object):
     def _separate(cls, expr, delim=',', max_split=None, skip_delims=None):
         if not expr:
             return
+        # collections.Counter() is ~10% slower
         counters = {k: 0 for k in _MATCHING_PARENS.values()}
+        # counters = Counter()
         start, splits, pos, delim_len = 0, 0, 0, len(delim) - 1
         in_quote, escaping, skipping = None, False, 0
         after_op, in_regex_char_group, skip_re = True, False, 0
@@ -442,6 +445,7 @@ class JSInterpreter(object):
             return ret, should_abort or should_return
 
         elif md.get('catch'):
+
             catch_expr, expr = self._separate_at_paren(expr[m.end():], '}')
             if self._EXC_NAME in local_vars:
                 catch_vars = local_vars.new_child({m.group('err'): local_vars.pop(self._EXC_NAME)})
@@ -450,6 +454,7 @@ class JSInterpreter(object):
                     return ret, True
 
             ret, should_abort = self.interpret_statement(expr, local_vars, allow_recursion)
+
             return ret, should_abort or should_return
 
         elif md.get('for'):