Fix building with Python 3.10

src/calibre/constants.py

@@ -2,7 +2,7 @@
 # vim:fileencoding=utf-8
 # License: GPLv3 Copyright: 2015, Kovid Goyal <kovid at kovidgoyal.net>
 from polyglot.builtins import map, unicode_type, environ_item, hasenv, getenv
-import sys, locale, codecs, os, collections
+import sys, locale, codecs, os, collections, collections.abc
 
 __appname__   = 'calibre'
 numeric_version = (5, 21, 0)
@@ -291,7 +291,7 @@ if iswindows:
     from calibre_extensions import winutil
 
 
-class Plugins(collections.Mapping):
+class Plugins(collections.abc.Mapping):
 
     def __iter__(self):
         from importlib.resources import contents

src/calibre/db/cache.py

@@ -12,7 +12,8 @@ import random
 import shutil
 import sys
 import traceback
-from collections import MutableSet, Set, defaultdict
+from collections import defaultdict
+from collections.abc import MutableSet, Set
 from functools import partial, wraps
 from io import BytesIO
 from threading import Lock

src/calibre/db/lazy.py

@@ -8,7 +8,7 @@ __docformat__ = 'restructuredtext en'
 
 import weakref
 from functools import wraps
-from collections import MutableMapping, MutableSequence
+from collections.abc import MutableMapping, MutableSequence
 from copy import deepcopy
 
 from calibre.ebooks.metadata.book.base import Metadata, SIMPLE_GET, TOP_LEVEL_IDENTIFIERS, NULL_VALUES, ALL_METADATA_FIELDS

src/calibre/test_build.py

@@ -48,7 +48,7 @@ class BuildTest(unittest.TestCase):
 
     def test_loaders(self):
         import importlib
-        ldr = importlib.import_module('calibre').__spec__.loader
+        ldr = importlib.import_module('calibre').__spec__.loader.get_resource_reader()
         self.assertIn('ebooks', ldr.contents())
         try:
             raw = ldr.open_resource('__init__.py').read()

src/calibre/utils/dbus_service.py

@@ -33,7 +33,7 @@ import sys
 import logging
 import threading
 import traceback
-from collections import Sequence
+from collections.abc import Sequence
 
 import _dbus_bindings
 from dbus import (

src/calibre/utils/run_tests.py

@@ -3,7 +3,7 @@
 # License: GPLv3 Copyright: 2016, Kovid Goyal <kovid at kovidgoyal.net>
 
 
-import unittest, functools, importlib
+import unittest, functools, importlib, importlib.resources
 from calibre.utils.monotonic import monotonic
 
 
@@ -54,8 +54,7 @@ class TestResult(unittest.TextTestResult):
 
 
 def find_tests_in_package(package, excludes=('main.py',)):
-    loader = importlib.import_module(package).__spec__.loader
-    items = list(loader.contents())
+    items = list(importlib.resources.contents(package))
     suits = []
     excludes = set(excludes) | {x + 'c' for x in excludes}
     seen = set()

src/css_selectors/ordered_set.py

@@ -5,7 +5,7 @@
 __license__ = 'GPL v3'
 __copyright__ = '2015, Kovid Goyal <kovid at kovidgoyal.net>'
 
-import collections
+import collections.abc
 from polyglot.builtins import string_or_bytes
 
 SLICE_ALL = slice(None)
@@ -23,7 +23,7 @@ def is_iterable(obj):
     return hasattr(obj, '__iter__') and not isinstance(obj, string_or_bytes)
 
 
-class OrderedSet(collections.MutableSet):
+class OrderedSet(collections.abc.MutableSet):
     """
     An OrderedSet is a custom MutableSet that remembers its order, so that
     every entry has an index that can be looked up.