Merge branch '3.x'

14 files changed, 138 insertions, 101 deletions

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index f277255cf..9e4dd2ade 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -4,11 +4,12 @@ on: [push, pull_request]
 
 jobs:
   ubuntu:
-    runs-on: ubuntu-16.04
+    runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
       matrix:
         name: [py36, py37, py38, py39]
+        os: [ubuntu-16.04]
         include:
         - name: py36
           python: 3.6
@@ -23,6 +24,10 @@ jobs:
           python: 3.9
           docutils: du16
           coverage: "--cov ./ --cov-append --cov-config setup.cfg"
+        - name: py310-dev
+          python: 3.10-dev
+          docutils: du16
+          os: ubuntu-latest  # required
     env:
       PYTEST_ADDOPTS: ${{ matrix.coverage }}
 
@@ -30,6 +35,12 @@ jobs:
     - uses: actions/checkout@v2
     - name: Set up Python ${{ matrix.python }}
       uses: actions/setup-python@v2
+      if: "!endsWith(matrix.python, '-dev')"
+      with:
+        python-version: ${{ matrix.python }}
+    - name: Set up Python ${{ matrix.python }} (deadsnakes)
+      uses: deadsnakes/action@v1.0.0
+      if: endsWith(matrix.python, '-dev')
       with:
         python-version: ${{ matrix.python }}
     - name: Check Python version
diff --git a/CHANGES b/CHANGES
index a9e91691c..b674c91dc 100644
--- a/CHANGES
+++ b/CHANGES
@@ -72,6 +72,11 @@ Features added
 * #8119: autodoc: Allow to determine whether a member not included in
   ``__all__`` attribute of the module should be documented or not via
   :event:`autodoc-skip-member` event
+* #8219: autodoc: Parameters for generic class are not shown when super class is
+  a generic class and show-inheritance option is given (in Python 3.7 or above)
+* autodoc: Add ``Documenter.config`` as a shortcut to access the config object
+* autodoc: Add Optional[t] to annotation of function and method if a default
+  value equal to None is set.
 * #6914: Add a new event :event:`warn-missing-reference` to custom warning
   messages when failed to resolve a cross-reference
 * #6914: Emit a detailed warning when failed to resolve a ``:ref:`` reference
@@ -105,8 +110,10 @@ Features added
 Bugs fixed
 ----------
 
-* #8219: autodoc: Parameters for generic class are not shown when super class is
-  a generic class and show-inheritance option is given (in Python 3.7 or above)
+* #8372: autodoc: autoclass directive became slower than Sphinx-3.2
+* #7727: autosummary: raise PycodeError when documenting python package
+  without __init__.py
+* #8364: C, properly initialize attributes in empty symbols.
 
 Testing
 --------
diff --git a/sphinx/domains/c.py b/sphinx/domains/c.py
index e3570b593..5896f4a80 100644
--- a/sphinx/domains/c.py
+++ b/sphinx/domains/c.py
@@ -1533,6 +1533,7 @@ class Symbol:
         self.declaration = declaration
         self.declaration.symbol = self
         self.docname = docname
+        self.line = line
         self._assert_invariants()
         # and symbol addition should be done as well
         self._add_function_params()
diff --git a/sphinx/ext/autodoc/__init__.py b/sphinx/ext/autodoc/__init__.py
index 9a6417a2e..cf92b0137 100644
--- a/sphinx/ext/autodoc/__init__.py
+++ b/sphinx/ext/autodoc/__init__.py
@@ -323,6 +323,7 @@ class Documenter:
 
     def __init__(self, directive: "DocumenterBridge", name: str, indent: str = '') -> None:
         self.directive = directive
+        self.config = directive.env.config
         self.env = directive.env    # type: BuildEnvironment
         self.options = directive.genopt
         self.name = name
@@ -393,7 +394,7 @@ class Documenter:
             modname = None
             parents = []
 
-        with mock(self.env.config.autodoc_mock_imports):
+        with mock(self.config.autodoc_mock_imports):
             self.modname, self.objpath = self.resolve_name(modname, parents, path, base)
 
         if not self.modname:
@@ -411,11 +412,11 @@ class Documenter:
 
         Returns True if successful, False if an error occurred.
         """
-        with mock(self.env.config.autodoc_mock_imports):
+        with mock(self.config.autodoc_mock_imports):
             try:
                 ret = import_object(self.modname, self.objpath, self.objtype,
                                     attrgetter=self.get_attr,
-                                    warningiserror=self.env.config.autodoc_warningiserror)
+                                    warningiserror=self.config.autodoc_warningiserror)
                 self.module, self.parent, self.object_name, self.object = ret
                 return True
             except ImportError as exc:
@@ -539,8 +540,7 @@ class Documenter:
             warnings.warn("The 'ignore' argument to autodoc.%s.get_doc() is deprecated."
                           % self.__class__.__name__,
                           RemovedInSphinx50Warning, stacklevel=2)
-        docstring = getdoc(self.object, self.get_attr,
-                           self.env.config.autodoc_inherit_docstrings,
+        docstring = getdoc(self.object, self.get_attr, self.config.autodoc_inherit_docstrings,
                            self.parent, self.object_name)
         if docstring:
             tab_width = self.directive.state.document.settings.tab_width
@@ -682,7 +682,7 @@ class Documenter:
             else:
                 isattr = False
 
-            doc = getdoc(member, self.get_attr, self.env.config.autodoc_inherit_docstrings,
+            doc = getdoc(member, self.get_attr, self.config.autodoc_inherit_docstrings,
                          self.parent, self.object_name)
             if not isinstance(doc, str):
                 # Ignore non-string __doc__
@@ -810,7 +810,7 @@ class Documenter:
             documenter = classes[-1](self.directive, full_mname, self.indent)
             memberdocumenters.append((documenter, isattr))
 
-        member_order = self.options.member_order or self.env.config.autodoc_member_order
+        member_order = self.options.member_order or self.config.autodoc_member_order
         memberdocumenters = self.sort_members(memberdocumenters, member_order)
 
         for documenter, isattr in memberdocumenters:
@@ -1194,7 +1194,7 @@ class DocstringSignatureMixin:
         return super().get_doc(ignore)  # type: ignore
 
     def format_signature(self, **kwargs: Any) -> str:
-        if self.args is None and self.env.config.autodoc_docstring_signature:  # type: ignore
+        if self.args is None and self.config.autodoc_docstring_signature:  # type: ignore
             # only act if a signature is not explicitly given already, and if
             # the feature is enabled
             result = self._find_signature()
@@ -1213,7 +1213,7 @@ class DocstringStripSignatureMixin(DocstringSignatureMixin):
     feature of stripping any function signature from the docstring.
     """
     def format_signature(self, **kwargs: Any) -> str:
-        if self.args is None and self.env.config.autodoc_docstring_signature:  # type: ignore
+        if self.args is None and self.config.autodoc_docstring_signature:  # type: ignore
             # only act if a signature is not explicitly given already, and if
             # the feature is enabled
             result = self._find_signature()
@@ -1240,13 +1240,12 @@ class FunctionDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # typ
                 (inspect.isroutine(member) and isinstance(parent, ModuleDocumenter)))
 
     def format_args(self, **kwargs: Any) -> str:
-        if self.env.config.autodoc_typehints in ('none', 'description'):
+        if self.config.autodoc_typehints in ('none', 'description'):
             kwargs.setdefault('show_annotation', False)
 
         try:
             self.env.app.emit('autodoc-before-process-signature', self.object, False)
-            sig = inspect.signature(self.object,
-                                    type_aliases=self.env.config.autodoc_type_aliases)
+            sig = inspect.signature(self.object, type_aliases=self.config.autodoc_type_aliases)
             args = stringify_signature(sig, **kwargs)
         except TypeError as exc:
             logger.warning(__("Failed to get a function signature for %s: %s"),
@@ -1255,7 +1254,7 @@ class FunctionDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # typ
         except ValueError:
             args = ''
 
-        if self.env.config.strip_signature_backslash:
+        if self.config.strip_signature_backslash:
             # escape backslashes for reST
             args = args.replace('\\', '\\\\')
         return args
@@ -1274,7 +1273,7 @@ class FunctionDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # typ
         sigs = []
         if (self.analyzer and
                 '.'.join(self.objpath) in self.analyzer.overloads and
-                self.env.config.autodoc_typehints == 'signature'):
+                self.config.autodoc_typehints == 'signature'):
             # Use signatures for overloaded functions instead of the implementation function.
             overloaded = True
         else:
@@ -1298,7 +1297,7 @@ class FunctionDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # typ
             __globals__ = safe_getattr(self.object, '__globals__', {})
             for overload in self.analyzer.overloads.get('.'.join(self.objpath)):
                 overload = evaluate_signature(overload, __globals__,
-                                              self.env.config.autodoc_type_aliases)
+                                              self.config.autodoc_type_aliases)
 
                 sig = stringify_signature(overload, **kwargs)
                 sigs.append(sig)
@@ -1308,7 +1307,7 @@ class FunctionDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # typ
     def annotate_to_first_argument(self, func: Callable, typ: Type) -> None:
         """Annotate type hint to the first argument of function if needed."""
         try:
-            sig = inspect.signature(func, type_aliases=self.env.config.autodoc_type_aliases)
+            sig = inspect.signature(func, type_aliases=self.config.autodoc_type_aliases)
         except TypeError as exc:
             logger.warning(__("Failed to get a function signature for %s: %s"),
                            self.fullname, exc)
@@ -1440,7 +1439,7 @@ class ClassDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # type:
             self.env.app.emit('autodoc-before-process-signature', call, True)
             try:
                 sig = inspect.signature(call, bound_method=True,
-                                        type_aliases=self.env.config.autodoc_type_aliases)
+                                        type_aliases=self.config.autodoc_type_aliases)
                 return type(self.object), '__call__', sig
             except ValueError:
                 pass
@@ -1456,7 +1455,7 @@ class ClassDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # type:
             self.env.app.emit('autodoc-before-process-signature', new, True)
             try:
                 sig = inspect.signature(new, bound_method=True,
-                                        type_aliases=self.env.config.autodoc_type_aliases)
+                                        type_aliases=self.config.autodoc_type_aliases)
                 return self.object, '__new__', sig
             except ValueError:
                 pass
@@ -1467,7 +1466,7 @@ class ClassDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # type:
             self.env.app.emit('autodoc-before-process-signature', init, True)
             try:
                 sig = inspect.signature(init, bound_method=True,
-                                        type_aliases=self.env.config.autodoc_type_aliases)
+                                        type_aliases=self.config.autodoc_type_aliases)
                 return self.object, '__init__', sig
             except ValueError:
                 pass
@@ -1479,7 +1478,7 @@ class ClassDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # type:
         self.env.app.emit('autodoc-before-process-signature', self.object, False)
         try:
             sig = inspect.signature(self.object, bound_method=False,
-                                    type_aliases=self.env.config.autodoc_type_aliases)
+                                    type_aliases=self.config.autodoc_type_aliases)
             return None, None, sig
         except ValueError:
             pass
@@ -1489,7 +1488,7 @@ class ClassDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # type:
         return None, None, None
 
     def format_args(self, **kwargs: Any) -> str:
-        if self.env.config.autodoc_typehints in ('none', 'description'):
+        if self.config.autodoc_typehints in ('none', 'description'):
             kwargs.setdefault('show_annotation', False)
 
         try:
@@ -1513,13 +1512,13 @@ class ClassDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # type:
         sigs = []
 
         overloads = self.get_overloaded_signatures()
-        if overloads and self.env.config.autodoc_typehints == 'signature':
+        if overloads and self.config.autodoc_typehints == 'signature':
             # Use signatures for overloaded methods instead of the implementation method.
             method = safe_getattr(self._signature_class, self._signature_method_name, None)
             __globals__ = safe_getattr(method, '__globals__', {})
             for overload in overloads:
                 overload = evaluate_signature(overload, __globals__,
-                                              self.env.config.autodoc_type_aliases)
+                                              self.config.autodoc_type_aliases)
 
                 parameters = list(overload.parameters.values())
                 overload = overload.replace(parameters=parameters[1:],
@@ -1540,6 +1539,9 @@ class ClassDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # type:
                     qualname = '.'.join([cls.__qualname__, self._signature_method_name])
                     if qualname in analyzer.overloads:
                         return analyzer.overloads.get(qualname)
+                    elif qualname in analyzer.tagorder:
+                        # the constructor is defined in the class, but not overrided.
+                        return []
                 except PycodeError:
                     pass
 
@@ -1575,7 +1577,7 @@ class ClassDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # type:
         if lines is not None:
             return lines
 
-        content = self.env.config.autoclass_content
+        content = self.config.autoclass_content
 
         docstrings = []
         attrdocstring = self.get_attr(self.object, '__doc__', None)
@@ -1587,7 +1589,7 @@ class ClassDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # type:
         if content in ('both', 'init'):
             __init__ = self.get_attr(self.object, '__init__', None)
             initdocstring = getdoc(__init__, self.get_attr,
-                                   self.env.config.autodoc_inherit_docstrings,
+                                   self.config.autodoc_inherit_docstrings,
                                    self.parent, self.object_name)
             # for new-style classes, no __init__ means default __init__
             if (initdocstring is not None and
@@ -1598,7 +1600,7 @@ class ClassDocumenter(DocstringSignatureMixin, ModuleLevelDocumenter):  # type:
                 # try __new__
                 __new__ = self.get_attr(self.object, '__new__', None)
                 initdocstring = getdoc(__new__, self.get_attr,
-                                       self.env.config.autodoc_inherit_docstrings,
+                                       self.config.autodoc_inherit_docstrings,
                                        self.parent, self.object_name)
                 # for new-style classes, no __new__ means default __new__
                 if (initdocstring is not None and
@@ -1863,7 +1865,7 @@ class MethodDocumenter(DocstringSignatureMixin, ClassLevelDocumenter):  # type:
         return ret
 
     def format_args(self, **kwargs: Any) -> str:
-        if self.env.config.autodoc_typehints in ('none', 'description'):
+        if self.config.autodoc_typehints in ('none', 'description'):
             kwargs.setdefault('show_annotation', False)
 
         try:
@@ -1877,11 +1879,11 @@ class MethodDocumenter(DocstringSignatureMixin, ClassLevelDocumenter):  # type:
                 if inspect.isstaticmethod(self.object, cls=self.parent, name=self.object_name):
                     self.env.app.emit('autodoc-before-process-signature', self.object, False)
                     sig = inspect.signature(self.object, bound_method=False,
-                                            type_aliases=self.env.config.autodoc_type_aliases)
+                                            type_aliases=self.config.autodoc_type_aliases)
                 else:
                     self.env.app.emit('autodoc-before-process-signature', self.object, True)
                     sig = inspect.signature(self.object, bound_method=True,
-                                            type_aliases=self.env.config.autodoc_type_aliases)
+                                            type_aliases=self.config.autodoc_type_aliases)
                 args = stringify_signature(sig, **kwargs)
         except TypeError as exc:
             logger.warning(__("Failed to get a method signature for %s: %s"),
@@ -1890,7 +1892,7 @@ class MethodDocumenter(DocstringSignatureMixin, ClassLevelDocumenter):  # type:
         except ValueError:
             args = ''
 
-        if self.env.config.strip_signature_backslash:
+        if self.config.strip_signature_backslash:
             # escape backslashes for reST
             args = args.replace('\\', '\\\\')
         return args
@@ -1918,7 +1920,7 @@ class MethodDocumenter(DocstringSignatureMixin, ClassLevelDocumenter):  # type:
         sigs = []
         if (self.analyzer and
                 '.'.join(self.objpath) in self.analyzer.overloads and
-                self.env.config.autodoc_typehints == 'signature'):
+                self.config.autodoc_typehints == 'signature'):
             # Use signatures for overloaded methods instead of the implementation method.
             overloaded = True
         else:
@@ -1944,7 +1946,7 @@ class MethodDocumenter(DocstringSignatureMixin, ClassLevelDocumenter):  # type:
             __globals__ = safe_getattr(self.object, '__globals__', {})
             for overload in self.analyzer.overloads.get('.'.join(self.objpath)):
                 overload = evaluate_signature(overload, __globals__,
-                                              self.env.config.autodoc_type_aliases)
+                                              self.config.autodoc_type_aliases)
 
                 if not inspect.isstaticmethod(self.object, cls=self.parent,
                                               name=self.object_name):
@@ -1958,7 +1960,7 @@ class MethodDocumenter(DocstringSignatureMixin, ClassLevelDocumenter):  # type:
     def annotate_to_first_argument(self, func: Callable, typ: Type) -> None:
         """Annotate type hint to the first argument of function if needed."""
         try:
-            sig = inspect.signature(func, type_aliases=self.env.config.autodoc_type_aliases)
+            sig = inspect.signature(func, type_aliases=self.config.autodoc_type_aliases)
         except TypeError as exc:
             logger.warning(__("Failed to get a method signature for %s: %s"),
                            self.fullname, exc)
@@ -2110,11 +2112,11 @@ class AttributeDocumenter(DocstringStripSignatureMixin, ClassLevelDocumenter):
             # Disable `autodoc_inherit_docstring` temporarily to avoid to obtain
             # a docstring from the value which descriptor returns unexpectedly.
             # ref: https://github.com/sphinx-doc/sphinx/issues/7805
-            orig = self.env.config.autodoc_inherit_docstrings
-            self.env.config.autodoc_inherit_docstrings = False  # type: ignore
+            orig = self.config.autodoc_inherit_docstrings
+            self.config.autodoc_inherit_docstrings = False  # type: ignore
             return super().get_doc(ignore)
         finally:
-            self.env.config.autodoc_inherit_docstrings = orig  # type: ignore
+            self.config.autodoc_inherit_docstrings = orig  # type: ignore
 
     def add_content(self, more_content: Any, no_docstring: bool = False) -> None:
         if not self._datadescriptor:
@@ -2223,11 +2225,11 @@ class SlotsAttributeDocumenter(AttributeDocumenter):
         self.objtype = 'attribute'
         self._datadescriptor = True
 
-        with mock(self.env.config.autodoc_mock_imports):
+        with mock(self.config.autodoc_mock_imports):
             try:
                 ret = import_object(self.modname, self.objpath[:-1], 'class',
                                     attrgetter=self.get_attr,
-                                    warningiserror=self.env.config.autodoc_warningiserror)
+                                    warningiserror=self.config.autodoc_warningiserror)
                 self.module, _, _, self.parent = ret
                 return True
             except ImportError as exc:
diff --git a/sphinx/ext/autosummary/__init__.py b/sphinx/ext/autosummary/__init__.py
index fba270acf..ee1785251 100644
--- a/sphinx/ext/autosummary/__init__.py
+++ b/sphinx/ext/autosummary/__init__.py
@@ -72,6 +72,7 @@ from docutils.statemachine import StringList
 import sphinx
 from sphinx import addnodes
 from sphinx.application import Sphinx
+from sphinx.config import Config
 from sphinx.deprecation import RemovedInSphinx50Warning
 from sphinx.environment import BuildEnvironment
 from sphinx.environment.adapters.toctree import TocTree
@@ -173,8 +174,10 @@ class FakeDirective(DocumenterBridge):
     def __init__(self) -> None:
         settings = Struct(tab_width=8)
         document = Struct(settings=settings)
+        env = BuildEnvironment()
+        env.config = Config()
         state = Struct(document=document)
-        super().__init__({}, None, Options(), 0, state)  # type: ignore
+        super().__init__(env, None, Options(), 0, state)
 
 
 def get_documenter(app: Sphinx, obj: Any, parent: Any) -> "Type[Documenter]":
@@ -664,7 +667,7 @@ def import_ivar_by_name(name: str, prefixes: List[str] = [None]) -> Tuple[str, A
         analyzer = ModuleAnalyzer.for_module(modname)
         if (qualname, attr) in analyzer.find_attr_docs():
             return real_name + "." + attr, INSTANCEATTR, obj, modname
-    except (ImportError, ValueError):
+    except (ImportError, ValueError, PycodeError):
         pass
 
     raise ImportError
diff --git a/sphinx/pycode/__init__.py b/sphinx/pycode/__init__.py
index 943c77244..8bc1ba6c1 100644
--- a/sphinx/pycode/__init__.py
+++ b/sphinx/pycode/__init__.py
@@ -139,9 +139,13 @@ class ModuleAnalyzer:
         self.overloads = None    # type: Dict[str, List[Signature]]
         self.tagorder = None     # type: Dict[str, int]
         self.tags = None         # type: Dict[str, Tuple[str, int, int]]
+        self._parsed = False
 
     def parse(self) -> None:
         """Parse the source code."""
+        if self._parsed:
+            return None
+
         try:
             parser = Parser(self.code)
             parser.parse()
@@ -158,19 +162,16 @@ class ModuleAnalyzer:
             self.overloads = parser.overloads
             self.tags = parser.definitions
             self.tagorder = parser.deforders
+            self._parsed = True
         except Exception as exc:
             raise PycodeError('parsing %r failed: %r' % (self.srcname, exc)) from exc
 
     def find_attr_docs(self) -> Dict[Tuple[str, str], List[str]]:
         """Find class and module-level attributes and their documentation."""
-        if self.attr_docs is None:
-            self.parse()
-
+        self.parse()
         return self.attr_docs
 
     def find_tags(self) -> Dict[str, Tuple[str, int, int]]:
         """Find class, function and method definitions and their location."""
-        if self.tags is None:
-            self.parse()
-
+        self.parse()
         return self.tags
diff --git a/sphinx/util/inspect.py b/sphinx/util/inspect.py
index 6912765e6..b8a149d05 100644
--- a/sphinx/util/inspect.py
+++ b/sphinx/util/inspect.py
@@ -453,10 +453,10 @@ def signature(subject: Callable, bound_method: bool = False, follow_wrapped: boo
             raise
 
     try:
-        # Update unresolved annotations using ``get_type_hints()``.
+        # Resolve annotations using ``get_type_hints()`` and type_aliases.
         annotations = typing.get_type_hints(subject, None, type_aliases)
         for i, param in enumerate(parameters):
-            if isinstance(param.annotation, str) and param.name in annotations:
+            if param.name in annotations:
                 parameters[i] = param.replace(annotation=annotations[param.name])
         if 'return' in annotations:
             return_annotation = annotations['return']
diff --git a/sphinx/util/typing.py b/sphinx/util/typing.py
index ab02f1f6b..ebd6518e0 100644
--- a/sphinx/util/typing.py
+++ b/sphinx/util/typing.py
@@ -215,7 +215,7 @@ def stringify(annotation: Any) -> str:
     if isinstance(annotation, str):
         if annotation.startswith("'") and annotation.endswith("'"):
             # might be a double Forward-ref'ed type.  Go unquoting.
-            return annotation[1:-2]
+            return annotation[1:-1]
         else:
             return annotation
     elif isinstance(annotation, TypeVar):
diff --git a/tests/test_build_linkcheck.py b/tests/test_build_linkcheck.py
index a78587668..908319e6b 100644
--- a/tests/test_build_linkcheck.py
+++ b/tests/test_build_linkcheck.py
@@ -11,10 +11,11 @@
 import http.server
 import json
 import re
-import threading
 from unittest import mock
 import pytest
 
+from utils import http_server
+
 
 @pytest.mark.sphinx('linkcheck', testroot='linkcheck', freshenv=True)
 def test_defaults(app, status, warning):
@@ -110,12 +111,12 @@ def test_anchors_ignored(app, status, warning):
 
 @pytest.mark.sphinx('linkcheck', testroot='linkcheck-localserver', freshenv=True)
 def test_raises_for_invalid_status(app, status, warning):
-    server_thread = HttpServerThread(InternalServerErrorHandler, daemon=True)
-    server_thread.start()
-    try:
+    class InternalServerErrorHandler(http.server.BaseHTTPRequestHandler):
+        def do_GET(self):
+            self.send_error(500, "Internal Server Error")
+
+    with http_server(InternalServerErrorHandler):
         app.builder.build_all()
-    finally:
-        server_thread.terminate()
     content = (app.outdir / 'output.txt').read_text()
     assert content == (
         "index.rst:1: [broken] http://localhost:7777/#anchor: "
@@ -177,22 +178,3 @@ def test_linkcheck_request_headers(app, status, warning):
                 assert headers["X-Secret"] == "open sesami"
             else:
                 assert headers["Accept"] == "text/html,application/xhtml+xml;q=0.9,*/*;q=0.8"
-
-
-class HttpServerThread(threading.Thread):
-    def __init__(self, handler, *args, **kwargs):
-        super().__init__(*args, **kwargs)
-        self.server = http.server.HTTPServer(("localhost", 7777), handler)
-
-    def run(self):
-        self.server.serve_forever(poll_interval=0.01)
-
-    def terminate(self):
-        self.server.shutdown()
-        self.server.server_close()
-        self.join()
-
-
-class InternalServerErrorHandler(http.server.BaseHTTPRequestHandler):
-    def do_GET(self):
-        self.send_error(500, "Internal Server Error")
diff --git a/tests/test_ext_autodoc_configs.py b/tests/test_ext_autodoc_configs.py
index a0eba20c8..19936c5ae 100644
--- a/tests/test_ext_autodoc_configs.py
+++ b/tests/test_ext_autodoc_configs.py
@@ -490,7 +490,7 @@ def test_autodoc_typehints_signature(app):
         '.. py:module:: target.typehints',
         '',
         '',
-        '.. py:class:: Math(s: str, o: Any = None)',
+        '.. py:class:: Math(s: str, o: Optional[Any] = None)',
         '   :module: target.typehints',
         '',
         '',
diff --git a/tests/test_ext_intersphinx.py b/tests/test_ext_intersphinx.py
index 53faa7a37..a88f64c71 100644
--- a/tests/test_ext_intersphinx.py
+++ b/tests/test_ext_intersphinx.py
@@ -8,13 +8,13 @@
     :license: BSD, see LICENSE for details.
 """
 
+import http.server
 import os
 import unittest
 from io import BytesIO
 from unittest import mock
 
 import pytest
-import requests
 from docutils import nodes
 from test_util_inventory import inventory_v2, inventory_v2_not_having_version
 
@@ -25,6 +25,8 @@ from sphinx.ext.intersphinx import (
 )
 from sphinx.ext.intersphinx import setup as intersphinx_setup
 
+from utils import http_server
+
 
 def fake_node(domain, type, target, content, **attrs):
     contnode = nodes.emphasis(content, content)
@@ -433,24 +435,22 @@ def test_inspect_main_file(capsys, tempdir):
     assert stderr == ""
 
 
-@mock.patch('requests.get')
-def test_inspect_main_url(fake_get, capsys):
+def test_inspect_main_url(capsys):
     """inspect_main interface, with url argument"""
-    raw = BytesIO(inventory_v2)
-    real_read = raw.read
+    class InventoryHandler(http.server.BaseHTTPRequestHandler):
+        def do_GET(self):
+            self.send_response(200, "OK")
+            self.end_headers()
+            self.wfile.write(inventory_v2)
 
-    def fake_read(*args, **kwargs):
-        return real_read()
+        def log_message(*args, **kwargs):
+            # Silenced.
+            pass
 
-    raw.read = fake_read
-    url = 'http://hostname/' + INVENTORY_FILENAME
-    resp = requests.Response()
-    resp.status_code = 200
-    resp.url = url
-    resp.raw = raw
-    fake_get.return_value = resp
+    url = 'http://localhost:7777/' + INVENTORY_FILENAME
 
-    inspect_main([url])
+    with http_server(InventoryHandler):
+        inspect_main([url])
 
     stdout, stderr = capsys.readouterr()
     assert stdout.startswith("c:function\n")
diff --git a/tests/test_util_inspect.py b/tests/test_util_inspect.py
index 7ffe95982..8103050f5 100644
--- a/tests/test_util_inspect.py
+++ b/tests/test_util_inspect.py
@@ -162,7 +162,7 @@ def test_signature_annotations():
 
     # Space around '=' for defaults
     sig = inspect.signature(f7)
-    assert stringify_signature(sig) == '(x: int = None, y: dict = {}) -> None'
+    assert stringify_signature(sig) == '(x: Optional[int] = None, y: dict = {}) -> None'
 
     # Callable types
     sig = inspect.signature(f8)
@@ -177,7 +177,10 @@ def test_signature_annotations():
 
     # Instance annotations
     sig = inspect.signature(f11)
-    assert stringify_signature(sig) == '(x: CustomAnnotation, y: 123) -> None'
+    if sys.version_info < (3, 10):
+        assert stringify_signature(sig) == '(x: CustomAnnotation, y: 123) -> None'
+    else:
+        assert stringify_signature(sig) == '(x: CustomAnnotation(), y: 123) -> None'
 
     # tuple with more than two items
     sig = inspect.signature(f12)
@@ -223,7 +226,7 @@ def test_signature_annotations():
     assert stringify_signature(sig) == '(self) -> List[typing_test_data.Node]'
 
     sig = inspect.signature(Node.__init__)
-    assert stringify_signature(sig) == '(self, parent: Optional[Node]) -> None'
+    assert stringify_signature(sig) == '(self, parent: Optional[typing_test_data.Node]) -> None'
 
     # show_annotation is False
     sig = inspect.signature(f7)
@@ -231,7 +234,7 @@ def test_signature_annotations():
 
     # show_return_annotation is False
     sig = inspect.signature(f7)
-    assert stringify_signature(sig, show_return_annotation=False) == '(x: int = None, y: dict = {})'
+    assert stringify_signature(sig, show_return_annotation=False) == '(x: Optional[int] = None, y: dict = {})'
 
 
 @pytest.mark.skipif(sys.version_info < (3, 8), reason='python 3.8+ is required.')
diff --git a/tests/utils.py b/tests/utils.py
new file mode 100644
index 000000000..182dc1df0
--- /dev/null
+++ b/tests/utils.py
@@ -0,0 +1,27 @@
+import contextlib
+import http.server
+import threading
+
+
+class HttpServerThread(threading.Thread):
+    def __init__(self, handler, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.server = http.server.HTTPServer(("localhost", 7777), handler)
+
+    def run(self):
+        self.server.serve_forever(poll_interval=0.01)
+
+    def terminate(self):
+        self.server.shutdown()
+        self.server.server_close()
+        self.join()
+
+
+@contextlib.contextmanager
+def http_server(handler):
+    server_thread = HttpServerThread(handler, daemon=True)
+    server_thread.start()
+    try:
+        yield server_thread
+    finally:
+        server_thread.terminate()
diff --git a/utils/release-checklist b/utils/release-checklist
index 582d26685..dad83c850 100644
--- a/utils/release-checklist
+++ b/utils/release-checklist
@@ -4,7 +4,7 @@ Release checklist
 for stable releases
 -------------------
 
-* open https://travis-ci.org/sphinx-doc/sphinx/branches and check **X.Y** branch is green
+* open https://github.com/sphinx-doc/sphinx/actions?query=branch:X.Y.x and all tests has passed
 * Run ``git fetch; git status`` and check nothing changed
 * ``python utils/bump_version.py X.Y.Z``
 * Check diff by ``git diff``
@@ -28,7 +28,7 @@ for stable releases
 for first beta releases
 -----------------------
 
-* open https://travis-ci.org/sphinx-doc/sphinx/branches and check **master** branch is green
+* open https://github.com/sphinx-doc/sphinx/actions?query=branch:master and all tests has passed
 * Run ``git fetch; git status`` and check nothing changed
 * Run ``python setup.py extract_messages``
 * Run ``(cd sphinx/locale; tx push -s)``
@@ -58,7 +58,7 @@ for first beta releases
 for other beta releases
 -----------------------
 
-* open https://travis-ci.org/sphinx-doc/sphinx/branches and check **X.Y** branch is green
+* open https://github.com/sphinx-doc/sphinx/actions?query=branch:X.x and all tests has passed
 * Run ``git fetch; git status`` and check nothing changed
 * ``python utils/bump_version.py X.Y.0bN``
 * Check diff by ``git diff``
@@ -81,7 +81,7 @@ for other beta releases
 for major releases
 ------------------
 
-* open https://travis-ci.org/sphinx-doc/sphinx/branches and check **X.Y** branch is green
+* open https://github.com/sphinx-doc/sphinx/actions?query=branch:X.x and all tests has passed
 * Run ``git fetch; git status`` and check nothing changed
 * Run ``(cd sphinx/locale; tx pull -a -f)``
 * Run ``python setup.py compile_catalog``