fix core tests and reorganize tests folder

fix core tests

xfail test that should be invalid

test correct default providers

failing tests

skip creating rar archives if rar is not installed

use gestdown instead of addic7ed

remove python2 stuff

reorganize tests folder

subliminal/core.py

@@ -117,6 +117,8 @@ def list_subtitles_provider(self, provider, video, languages):
         except Exception as e:
             handle_exception(e, 'Provider {}'.format(provider))
 
+        return []
+
     def list_subtitles(self, video, languages):
         """List subtitles.
 

subliminal/subtitle.py

@@ -54,12 +54,12 @@ def __init__(self, language, hearing_impaired=False, page_link=None, encoding=No
     @property
     def id(self):
         """Unique identifier of the subtitle"""
-        raise NotImplementedError
+        return ""
 
     @property
     def info(self):
         """Info of the subtitle, human readable. Usually the subtitle name for GUI rendering"""
-        raise NotImplementedError
+        return ""
 
     @property
     def text(self):
@@ -94,12 +94,18 @@ def is_valid(self):
             return False
 
         try:
-            srt.parse(self.text)
+            self.parsed()
         except srt.SRTParseError:
             return False
 
         return True
 
+    def parsed(self):
+        """Text content parsed to a valid subtitle.
+
+        """
+        return srt.compose(srt.parse(self.text))
+
     def guess_encoding(self):
         """Guess encoding using the language, falling back on chardet.
 

subliminal/utils.py

@@ -6,7 +6,7 @@
 import re
 import socket
 import struct
-from datetime import datetime
+from datetime import datetime, timezone
 
 import requests
 from requests.exceptions import SSLError
@@ -154,14 +154,14 @@ def sanitize_release_group(string):
 
 
 def timestamp(date):
-    """Get the timestamp of the `date`, python2/3 compatible
+    """Get the timestamp of the `date` (with timezone).
 
     :param datetime.datetime date: the utc date.
     :return: the timestamp of the date.
     :rtype: float
 
     """
-    return (date - datetime(1970, 1, 1)).total_seconds()
+    return (date - datetime(1970, 1, 1, tzinfo=timezone.utc)).total_seconds()
 
 
 def matches_title(actual, title, alternative_titles):