Use six for reraise

src/calibre/db/backend.py

@@ -11,6 +11,7 @@ __docformat__ = 'restructuredtext en'
 import os, shutil, uuid, json, glob, time, hashlib, errno, sys
 from functools import partial
 
+import six
 import apsw
 
 from calibre import isbytestring, force_unicode, prints, as_unicode
@@ -1626,7 +1627,7 @@ class DB(object):
             except EnvironmentError as err:
                 if err.errno == errno.EEXIST:
                     # Parent directory already exists, re-raise original exception
-                    raise exc_info[0], exc_info[1], exc_info[2]
+                    six.reraise(*exc_info)
                 raise
             finally:
                 del exc_info

src/calibre/ebooks/readability/readability.py

@@ -6,6 +6,7 @@ from __future__ import (unicode_literals, division, absolute_import,
 import re, sys
 from collections import defaultdict
 
+import six
 from lxml.etree import tostring
 from lxml.html import (fragment_fromstring, document_fromstring,
         tostring as htostring)
@@ -156,7 +157,7 @@ class Document:
                     return cleaned_article
         except StandardError as e:
             self.log.exception('error getting summary: ')
-            raise Unparseable(str(e)), None, sys.exc_info()[2]
+            six.reraise(Unparseable, Unparseable(str(e)), sys.exc_info()[2])
 
     def get_article(self, candidates, best_candidate):
         # Now that we have the top candidate, look through its siblings for content that might also be related.

src/calibre/gui2/icon_theme.py

@@ -14,6 +14,7 @@ from Queue import Queue, Empty
 from threading import Thread, Event
 from multiprocessing.pool import ThreadPool
 
+import six
 from PyQt5.Qt import (
     QImageReader, QFormLayout, QVBoxLayout, QSplitter, QGroupBox, QListWidget,
     QLineEdit, QSpinBox, QTextEdit, QSize, QListWidgetItem, QIcon, QImage,
@@ -368,7 +369,7 @@ def create_themeball(report, progress=None, abort=None):
         return
     if errors:
         e = errors[0]
-        raise e[0], e[1], e[2]
+        six.reraise(*e)
 
     if progress is not None:
         progress(next(num), _('Creating theme file'))

src/calibre/gui2/linux_file_dialogs.py

@@ -11,6 +11,7 @@ import sys
 import time
 from threading import Thread
 
+import six
 from PyQt5.Qt import QEventLoop
 
 from calibre import force_unicode
@@ -314,7 +315,7 @@ def linux_native_dialog(name):
             t.start()
             loop.exec_(QEventLoop.ExcludeUserInputEvents)
             if ret[1] is not None:
-                raise ret[1][0], ret[1][1], ret[1][2]
+                six.reraise(*ret[1])
             return ret[0]
         except Exception:
             linux_native_dialog.native_failed = True

src/calibre/srv/http_response.py

@@ -14,6 +14,8 @@ from operator import itemgetter
 from functools import wraps
 from future_builtins import map
 
+import six
+
 from calibre import guess_type, force_unicode
 from calibre.constants import __version__, plugins
 from calibre.srv.loop import WRITE
@@ -478,7 +480,7 @@ class HTTPConnection(HTTPRequest):
                 if e.log:
                     self.log.warn(e.log)
                 return self.simple_response(e.http_code, msg=e.message or '', close_after_response=e.close_connection, extra_headers=eh)
-            raise etype, e, tb
+            six.reraise(etype, e, tb)
 
         data, output = result
         output = self.finalize_output(output, data, self.method is HTTP1)

src/calibre/utils/shared_file.py

@@ -7,6 +7,9 @@ __license__ = 'GPL v3'
 __copyright__ = '2015, Kovid Goyal <kovid at kovidgoyal.net>'
 
 import os, sys
+
+import six
+
 from calibre.constants import iswindows, plugins
 
 '''
@@ -119,7 +122,11 @@ if iswindows:
     }
 
     def raise_winerror(pywinerr):
-        raise WindowsError(pywinerr.winerror, (pywinerr.funcname or '') + b': ' + (pywinerr.strerror or '')), None, sys.exc_info()[2]
+        six.reraise(
+            WindowsError,
+            WindowsError(pywinerr.winerror,
+                         (pywinerr.funcname or '') + b': ' + (pywinerr.strerror or '')),
+            sys.exc_info()[2])
 
     def os_open(path, flags, mode=0o777, share_flags=FILE_SHARE_VALID_FLAGS):
         '''
@@ -173,7 +180,7 @@ else:
         return speedup.fdopen(os.open(path, flags), path, mode, buffering)
 
     def raise_winerror(x):
-        raise NotImplementedError(), None, sys.exc_info()[2]
+        six.reraise(NotImplementedError, None, sys.exc_info()[2])
 
 
 def find_tests():

src/duktape/__init__.py

@@ -12,6 +12,7 @@ __all__ = ['dukpy', 'Context', 'undefined', 'JSError', 'to_python']
 import errno, os, sys, numbers, hashlib, json
 from functools import partial
 
+import six
 import dukpy
 
 from calibre.constants import iswindows
@@ -157,7 +158,7 @@ class Function(object):
             self.reraise(e)
 
     def reraise(self, e):
-        raise JSError(e), None, sys.exc_info()[2]
+        six.reraise(JSError, JSError(e), sys.exc_info()[2])
 
 def to_python(x):
     try:
@@ -332,7 +333,7 @@ class Context(object):
         '<init>')
 
     def reraise(self, e):
-        raise JSError(e), None, sys.exc_info()[2]
+        six.reraise(JSError, JSError(e), sys.exc_info()[2])
 
     def eval(self, code='', fname='<eval>', noreturn=False):
         try: