Run the ``pyupgrade`` tool

31 files changed, 68 insertions, 75 deletions

diff --git a/tests/roots/test-apidoc-toc/mypackage/main.py b/tests/roots/test-apidoc-toc/mypackage/main.py
index d448cc847..f532813a7 100755
--- a/tests/roots/test-apidoc-toc/mypackage/main.py
+++ b/tests/roots/test-apidoc-toc/mypackage/main.py
@@ -6,10 +6,10 @@ import mod_resource
 import mod_something
 
 if __name__ == "__main__":
-    print("Hello, world! -> something returns: {}".format(mod_something.something()))
+    print(f"Hello, world! -> something returns: {mod_something.something()}")
 
     res_path = \
         os.path.join(os.path.dirname(mod_resource.__file__), 'resource.txt')
     with open(res_path, encoding='utf-8') as f:
         text = f.read()
-    print("From mod_resource:resource.txt -> {}".format(text))
+    print(f"From mod_resource:resource.txt -> {text}")
diff --git a/tests/roots/test-autosummary/underscore_module_.py b/tests/roots/test-autosummary/underscore_module_.py
index c18697cd2..8584e6078 100644
--- a/tests/roots/test-autosummary/underscore_module_.py
+++ b/tests/roots/test-autosummary/underscore_module_.py
@@ -3,7 +3,7 @@ module with trailing underscores everywhere
 """
 
 
-class class_(object):
+class class_:
     """ Class """
     def method_(_arg):
         """ Method """
diff --git a/tests/roots/test-changes/conf.py b/tests/roots/test-changes/conf.py
index 2fedcb199..e9158c429 100644
--- a/tests/roots/test-changes/conf.py
+++ b/tests/roots/test-changes/conf.py
@@ -1,5 +1,3 @@
-# -*- coding: utf-8 -*-
-
 project = 'Sphinx ChangesBuilder tests'
 copyright = '2007-2022 by the Sphinx team, see AUTHORS'
 version = '0.6'
diff --git a/tests/roots/test-correct-year/conf.py b/tests/roots/test-correct-year/conf.py
index 6aac1743e..814c08b55 100644
--- a/tests/roots/test-correct-year/conf.py
+++ b/tests/roots/test-correct-year/conf.py
@@ -1,2 +1 @@
-
 copyright = '2006-2009, Author'
diff --git a/tests/roots/test-directive-only/conf.py b/tests/roots/test-directive-only/conf.py
index b9209f08b..191d0f598 100644
--- a/tests/roots/test-directive-only/conf.py
+++ b/tests/roots/test-directive-only/conf.py
@@ -1,3 +1,2 @@
-
 project = 'test-directive-only'
 exclude_patterns = ['_build']
diff --git a/tests/roots/test-ext-autodoc/autodoc_dummy_bar.py b/tests/roots/test-ext-autodoc/autodoc_dummy_bar.py
index 151818b36..3b5bbfdd1 100644
--- a/tests/roots/test-ext-autodoc/autodoc_dummy_bar.py
+++ b/tests/roots/test-ext-autodoc/autodoc_dummy_bar.py
@@ -1,6 +1,6 @@
 from bug2437.autodoc_dummy_foo import Foo
 
 
-class Bar(object):
+class Bar:
     """Dummy class Bar with alias."""
     my_name = Foo
diff --git a/tests/roots/test-ext-autodoc/bug2437/autodoc_dummy_foo.py b/tests/roots/test-ext-autodoc/bug2437/autodoc_dummy_foo.py
index b578a2255..9c954d80a 100644
--- a/tests/roots/test-ext-autodoc/bug2437/autodoc_dummy_foo.py
+++ b/tests/roots/test-ext-autodoc/bug2437/autodoc_dummy_foo.py
@@ -1,3 +1,3 @@
-class Foo(object):
+class Foo:
     """Dummy class Foo."""
     pass
diff --git a/tests/roots/test-ext-autodoc/target/__init__.py b/tests/roots/test-ext-autodoc/target/__init__.py
index 0d39c6672..bb2290be6 100644
--- a/tests/roots/test-ext-autodoc/target/__init__.py
+++ b/tests/roots/test-ext-autodoc/target/__init__.py
@@ -33,7 +33,7 @@ def _funky_classmethod(name, b, c, d, docstring=None):
     return classmethod(function)
 
 
-class Class(object):
+class Class:
     """Class to document."""
 
     def meth(self):
@@ -96,10 +96,10 @@ def function(foo, *args, **kwds):
     pass
 
 
-class Outer(object):
+class Outer:
     """Foo"""
 
-    class Inner(object):
+    class Inner:
         """Foo"""
 
         def meth(self):
@@ -113,7 +113,7 @@ class InnerChild(Outer.Inner):
     """InnerChild docstring"""
 
 
-class DocstringSig(object):
+class DocstringSig:
     def __new__(cls, *new_args, **new_kwargs):
         """__new__(cls, d, e=1) -> DocstringSig
 First line of docstring
@@ -164,12 +164,12 @@ class StrRepr(str):
         return self
 
 
-class AttCls(object):
+class AttCls:
     a1 = StrRepr('hello\nworld')
     a2 = None
 
 
-class InstAttCls(object):
+class InstAttCls:
     """Class with documented class and instance attributes."""
 
     #: Doc comment for class attribute InstAttCls.ca1.
@@ -189,7 +189,7 @@ class InstAttCls(object):
         """Docstring for instance attribute InstAttCls.ia2."""
 
 
-class CustomIter(object):
+class CustomIter:
     def __init__(self):
         """Create a new `CustomIter`."""
         self.values = range(10)
diff --git a/tests/roots/test-ext-autodoc/target/descriptor.py b/tests/roots/test-ext-autodoc/target/descriptor.py
index 63d179b65..2857c99f9 100644
--- a/tests/roots/test-ext-autodoc/target/descriptor.py
+++ b/tests/roots/test-ext-autodoc/target/descriptor.py
@@ -1,4 +1,4 @@
-class CustomDataDescriptor(object):
+class CustomDataDescriptor:
     """Descriptor class docstring."""
 
     def __init__(self, doc):
diff --git a/tests/roots/test-ext-autodoc/target/inheritance.py b/tests/roots/test-ext-autodoc/target/inheritance.py
index 85d95cd74..e06f7a842 100644
--- a/tests/roots/test-ext-autodoc/target/inheritance.py
+++ b/tests/roots/test-ext-autodoc/target/inheritance.py
@@ -1,4 +1,4 @@
-class Base(object):
+class Base:
     #: docstring
     inheritedattr = None
 
diff --git a/tests/roots/test-ext-autodoc/target/need_mocks.py b/tests/roots/test-ext-autodoc/target/need_mocks.py
index 45b3ade06..881220bd0 100644
--- a/tests/roots/test-ext-autodoc/target/need_mocks.py
+++ b/tests/roots/test-ext-autodoc/target/need_mocks.py
@@ -1,4 +1,3 @@
-
 import missing_module
 import missing_package1.missing_module1
 from missing_module import missing_name
@@ -20,7 +19,7 @@ def func(arg: missing_module.Class):
     pass
 
 
-class TestAutodoc(object):
+class TestAutodoc:
     """TestAutodoc docstring."""
 
     #: docstring
diff --git a/tests/roots/test-ext-autodoc/target/partialmethod.py b/tests/roots/test-ext-autodoc/target/partialmethod.py
index 82843461f..20d75e91d 100644
--- a/tests/roots/test-ext-autodoc/target/partialmethod.py
+++ b/tests/roots/test-ext-autodoc/target/partialmethod.py
@@ -1,7 +1,7 @@
 from functools import partialmethod
 
 
-class Cell(object):
+class Cell:
     """An example for partialmethod.
 
     refs: https://docs.python.jp/3/library/functools.html#functools.partialmethod
diff --git a/tests/roots/test-ext-autodoc/target/typed_vars.py b/tests/roots/test-ext-autodoc/target/typed_vars.py
index f909b80f1..0fe7468c8 100644
--- a/tests/roots/test-ext-autodoc/target/typed_vars.py
+++ b/tests/roots/test-ext-autodoc/target/typed_vars.py
@@ -8,7 +8,7 @@ attr3 = ''  # type: str
 
 class _Descriptor:
     def __init__(self, name):
-        self.__doc__ = "This is {}".format(name)
+        self.__doc__ = f"This is {name}"
     def __get__(self):
         pass
 
diff --git a/tests/roots/test-ext-inheritance_diagram/example/sphinx.py b/tests/roots/test-ext-inheritance_diagram/example/sphinx.py
index 5eb8a2291..2bfbf4c59 100644
--- a/tests/roots/test-ext-inheritance_diagram/example/sphinx.py
+++ b/tests/roots/test-ext-inheritance_diagram/example/sphinx.py
@@ -1,5 +1,5 @@
 # example.sphinx
 
 
-class DummyClass(object):
+class DummyClass:
     pass
diff --git a/tests/roots/test-ext-inheritance_diagram/test.py b/tests/roots/test-ext-inheritance_diagram/test.py
index 7d5cabeef..4f73c4707 100644
--- a/tests/roots/test-ext-inheritance_diagram/test.py
+++ b/tests/roots/test-ext-inheritance_diagram/test.py
@@ -1,4 +1,4 @@
-class Foo(object):
+class Foo:
     pass
 
 
diff --git a/tests/roots/test-ext-viewcode-find/not_a_package/submodule.py b/tests/roots/test-ext-viewcode-find/not_a_package/submodule.py
index 7bb36943b..ba8be78de 100644
--- a/tests/roots/test-ext-viewcode-find/not_a_package/submodule.py
+++ b/tests/roots/test-ext-viewcode-find/not_a_package/submodule.py
@@ -17,13 +17,13 @@ def func1(a, b):
 
 
 @decorator
-class Class1(object):
+class Class1:
     """
     this is Class1
     """
 
 
-class Class3(object):
+class Class3:
     """
     this is Class3
     """
diff --git a/tests/roots/test-inheritance/dummy/test.py b/tests/roots/test-inheritance/dummy/test.py
index 51bd9a7a4..12fe8d900 100644
--- a/tests/roots/test-inheritance/dummy/test.py
+++ b/tests/roots/test-inheritance/dummy/test.py
@@ -11,7 +11,7 @@ r"""
 """
 
 
-class A(object):
+class A:
     pass
 
 
diff --git a/tests/roots/test-inheritance/dummy/test_nested.py b/tests/roots/test-inheritance/dummy/test_nested.py
index 89289fe44..4b6801892 100644
--- a/tests/roots/test-inheritance/dummy/test_nested.py
+++ b/tests/roots/test-inheritance/dummy/test_nested.py
@@ -2,8 +2,8 @@
 """
 
 
-class A(object):
-    class B(object):
+class A:
+    class B:
         pass
 
 
diff --git a/tests/roots/test-root/autodoc_target.py b/tests/roots/test-root/autodoc_target.py
index a49ffc1ff..59f6c74d6 100644
--- a/tests/roots/test-root/autodoc_target.py
+++ b/tests/roots/test-root/autodoc_target.py
@@ -19,7 +19,7 @@ class CustomEx(Exception):
         """Exception method."""
 
 
-class CustomDataDescriptor(object):
+class CustomDataDescriptor:
     """Descriptor class docstring."""
 
     def __init__(self, doc):
@@ -56,7 +56,7 @@ def _funky_classmethod(name, b, c, d, docstring=None):
     return classmethod(function)
 
 
-class Base(object):
+class Base:
     def inheritedmeth(self):
         """Inherited function."""
 
@@ -136,10 +136,10 @@ def function(foo, *args, **kwds):
     pass
 
 
-class Outer(object):
+class Outer:
     """Foo"""
 
-    class Inner(object):
+    class Inner:
         """Foo"""
 
         def meth(self):
@@ -149,7 +149,7 @@ class Outer(object):
     factory = dict
 
 
-class DocstringSig(object):
+class DocstringSig:
     def meth(self):
         """meth(FOO, BAR=1) -> BAZ
 First line of docstring
@@ -184,12 +184,12 @@ class StrRepr(str):
         return self
 
 
-class AttCls(object):
+class AttCls:
     a1 = StrRepr('hello\nworld')
     a2 = None
 
 
-class InstAttCls(object):
+class InstAttCls:
     """Class with documented class and instance attributes."""
 
     #: Doc comment for class attribute InstAttCls.ca1.
diff --git a/tests/roots/test-warnings/autodoc_fodder.py b/tests/roots/test-warnings/autodoc_fodder.py
index e5fd74139..59e4e210f 100644
--- a/tests/roots/test-warnings/autodoc_fodder.py
+++ b/tests/roots/test-warnings/autodoc_fodder.py
@@ -1,5 +1,4 @@
-
-class MarkupError(object):
+class MarkupError:
     """
     .. note:: This is a docstring with a
     small markup error which should have
diff --git a/tests/test_build_epub.py b/tests/test_build_epub.py
index 80525112b..becde92cd 100644
--- a/tests/test_build_epub.py
+++ b/tests/test_build_epub.py
@@ -2,7 +2,7 @@
 
 import os
 import subprocess
-from subprocess import PIPE, CalledProcessError
+from subprocess import CalledProcessError
 from xml.etree import ElementTree
 
 import pytest
@@ -11,7 +11,7 @@ import pytest
 # check given command is runnable
 def runnable(command):
     try:
-        subprocess.run(command, stdout=PIPE, stderr=PIPE, check=True)
+        subprocess.run(command, capture_output=True, check=True)
         return True
     except (OSError, CalledProcessError):
         return False  # command not found or exit with non-zero
@@ -377,7 +377,7 @@ def test_run_epubcheck(app):
     if runnable(['java', '-version']) and os.path.exists(epubcheck):
         try:
             subprocess.run(['java', '-jar', epubcheck, app.outdir / 'SphinxTests.epub'],
-                           stdout=PIPE, stderr=PIPE, check=True)
+                           capture_output=True, check=True)
         except CalledProcessError as exc:
             print(exc.stdout.decode('utf-8'))
             print(exc.stderr.decode('utf-8'))
diff --git a/tests/test_build_gettext.py b/tests/test_build_gettext.py
index 20fe60e85..630f0760c 100644
--- a/tests/test_build_gettext.py
+++ b/tests/test_build_gettext.py
@@ -4,7 +4,7 @@ import gettext
 import os
 import re
 import subprocess
-from subprocess import PIPE, CalledProcessError
+from subprocess import CalledProcessError
 
 import pytest
 
@@ -54,7 +54,7 @@ def test_msgfmt(app):
     with cd(app.outdir):
         try:
             args = ['msginit', '--no-translator', '-i', 'markup.pot', '--locale', 'en_US']
-            subprocess.run(args, stdout=PIPE, stderr=PIPE, check=True)
+            subprocess.run(args, capture_output=True, check=True)
         except OSError:
             pytest.skip()  # most likely msginit was not found
         except CalledProcessError as exc:
@@ -66,7 +66,7 @@ def test_msgfmt(app):
         try:
             args = ['msgfmt', 'en_US.po',
                     '-o', os.path.join('en', 'LC_MESSAGES', 'test_root.mo')]
-            subprocess.run(args, stdout=PIPE, stderr=PIPE, check=True)
+            subprocess.run(args, capture_output=True, check=True)
         except OSError:
             pytest.skip()  # most likely msgfmt was not found
         except CalledProcessError as exc:
diff --git a/tests/test_build_html.py b/tests/test_build_html.py
index fa0bbac7c..dee65613f 100644
--- a/tests/test_build_html.py
+++ b/tests/test_build_html.py
@@ -105,9 +105,9 @@ def check_xpath(etree, fname, path, check, be_found=True):
             if all(not rex.search(get_text(node)) for node in nodes):
                 return
 
-        raise AssertionError(('%r not found in any node matching '
-                              'path %s in %s: %r' % (check, path, fname,
-                                                     [node.text for node in nodes])))
+        raise AssertionError('%r not found in any node matching '
+                             'path %s in %s: %r' % (check, path, fname,
+                                                    [node.text for node in nodes]))
 
 
 @pytest.mark.sphinx('html', testroot='warnings')
diff --git a/tests/test_build_latex.py b/tests/test_build_latex.py
index f8b06562b..bfb126953 100644
--- a/tests/test_build_latex.py
+++ b/tests/test_build_latex.py
@@ -5,7 +5,7 @@ import re
 import subprocess
 from itertools import product
 from shutil import copyfile
-from subprocess import PIPE, CalledProcessError
+from subprocess import CalledProcessError
 
 import pytest
 
@@ -36,7 +36,7 @@ LATEX_WARNINGS = ENV_WARNINGS + """\
 # only run latex if all needed packages are there
 def kpsetest(*filenames):
     try:
-        subprocess.run(['kpsewhich'] + list(filenames), stdout=PIPE, stderr=PIPE, check=True)
+        subprocess.run(['kpsewhich'] + list(filenames), capture_output=True, check=True)
         return True
     except (OSError, CalledProcessError):
         return False  # command not found or exit with non-zero
@@ -55,7 +55,7 @@ def compile_latex_document(app, filename='python.tex'):
                     '--interaction=nonstopmode',
                     '-output-directory=%s' % app.config.latex_engine,
                     filename]
-            subprocess.run(args, stdout=PIPE, stderr=PIPE, check=True)
+            subprocess.run(args, capture_output=True, check=True)
     except OSError as exc:  # most likely the latex executable was not found
         raise pytest.skip.Exception from exc
     except CalledProcessError as exc:
diff --git a/tests/test_build_texinfo.py b/tests/test_build_texinfo.py
index b33a7e01f..974cb1965 100644
--- a/tests/test_build_texinfo.py
+++ b/tests/test_build_texinfo.py
@@ -3,7 +3,7 @@
 import os
 import re
 import subprocess
-from subprocess import PIPE, CalledProcessError
+from subprocess import CalledProcessError
 from unittest.mock import Mock
 
 import pytest
@@ -49,7 +49,7 @@ def test_texinfo(app, status, warning):
     # now, try to run makeinfo over it
     try:
         args = ['makeinfo', '--no-split', 'sphinxtests.texi']
-        subprocess.run(args, stdout=PIPE, stderr=PIPE, cwd=app.outdir, check=True)
+        subprocess.run(args, capture_output=True, cwd=app.outdir, check=True)
     except OSError as exc:
         raise pytest.skip.Exception from exc  # most likely makeinfo was not found
     except CalledProcessError as exc:
diff --git a/tests/test_domain_c.py b/tests/test_domain_c.py
index 8a9a04568..9718297ab 100644
--- a/tests/test_domain_c.py
+++ b/tests/test_domain_c.py
@@ -470,12 +470,12 @@ def test_domain_c_ast_function_definitions():
     cvrs = ['', 'const', 'volatile', 'restrict', 'restrict volatile const']
     for cvr in cvrs:
         space = ' ' if len(cvr) != 0 else ''
-        check('function', 'void f(int arr[{}*])'.format(cvr), {1: 'f'})
-        check('function', 'void f(int arr[{}])'.format(cvr), {1: 'f'})
-        check('function', 'void f(int arr[{}{}42])'.format(cvr, space), {1: 'f'})
-        check('function', 'void f(int arr[static{}{} 42])'.format(space, cvr), {1: 'f'})
-        check('function', 'void f(int arr[{}{}static 42])'.format(cvr, space), {1: 'f'},
-              output='void f(int arr[static{}{} 42])'.format(space, cvr))
+        check('function', f'void f(int arr[{cvr}*])', {1: 'f'})
+        check('function', f'void f(int arr[{cvr}])', {1: 'f'})
+        check('function', f'void f(int arr[{cvr}{space}42])', {1: 'f'})
+        check('function', f'void f(int arr[static{space}{cvr} 42])', {1: 'f'})
+        check('function', f'void f(int arr[{cvr}{space}static 42])', {1: 'f'},
+              output=f'void f(int arr[static{space}{cvr} 42])')
     check('function', 'void f(int arr[const static volatile 42])', {1: 'f'},
           output='void f(int arr[static volatile const 42])')
 
@@ -611,9 +611,9 @@ def split_warnigns(warning):
 
 def filter_warnings(warning, file):
     lines = split_warnigns(warning)
-    res = [l for l in lines if "domain-c" in l and "{}.rst".format(file) in l and
+    res = [l for l in lines if "domain-c" in l and f"{file}.rst" in l and
            "WARNING: document isn't included in any toctree" not in l]
-    print("Filtered warnings for file '{}':".format(file))
+    print(f"Filtered warnings for file '{file}':")
     for w in res:
         print(w)
     return res
@@ -652,7 +652,7 @@ def test_domain_c_build_namespace(app, status, warning):
     assert len(ws) == 0
     t = (app.outdir / "namespace.html").read_text(encoding='utf8')
     for id_ in ('NS.NSVar', 'NULLVar', 'ZeroVar', 'NS2.NS3.NS2NS3Var', 'PopVar'):
-        assert 'id="c.{}"'.format(id_) in t
+        assert f'id="c.{id_}"' in t
 
 
 @pytest.mark.sphinx(testroot='domain-c', confoverrides={'nitpicky': True})
diff --git a/tests/test_domain_cpp.py b/tests/test_domain_cpp.py
index 5e9bc6aa3..93a43c754 100644
--- a/tests/test_domain_cpp.py
+++ b/tests/test_domain_cpp.py
@@ -218,7 +218,7 @@ def test_domain_cpp_ast_expressions():
              ('\\U0001f34c', '127820'), ('\\U0001F34C', '127820')]
     for p, t in charPrefixAndIds:
         for c, val in chars:
-            exprCheck("{}'{}'".format(p, c), t + val)
+            exprCheck(f"{p}'{c}'", t + val)
     # user-defined literals
     for i in ints:
         exprCheck(i + '_udl', 'clL_Zli4_udlEL' + i.replace("'", "") + 'EE')
@@ -230,7 +230,7 @@ def test_domain_cpp_ast_expressions():
         exprCheck('0x' + f + '_udl', 'clL_Zli4_udlEL0x' + f.replace("'", "") + 'EE')
     for p, t in charPrefixAndIds:
         for c, val in chars:
-            exprCheck("{}'{}'_udl".format(p, c), 'clL_Zli4_udlE' + t + val + 'E')
+            exprCheck(f"{p}'{c}'_udl", 'clL_Zli4_udlE' + t + val + 'E')
     exprCheck('"abc"_udl', 'clL_Zli4_udlELA3_KcEE')
     # from issue #7294
     exprCheck('6.62607015e-34q_J', 'clL_Zli3q_JEL6.62607015e-34EE')
@@ -1084,9 +1084,9 @@ def test_domain_cpp_template_parameters_is_pack(param: str, is_pack: bool):
 
 def filter_warnings(warning, file):
     lines = warning.getvalue().split("\n")
-    res = [l for l in lines if "domain-cpp" in l and "{}.rst".format(file) in l and
+    res = [l for l in lines if "domain-cpp" in l and f"{file}.rst" in l and
            "WARNING: document isn't included in any toctree" not in l]
-    print("Filtered warnings for file '{}':".format(file))
+    print(f"Filtered warnings for file '{file}':")
     for w in res:
         print(w)
     return res
@@ -1169,10 +1169,10 @@ def test_domain_cpp_build_misuse_of_roles(app, status, warning):
         txtTargetType = "function" if targetType == "func" else targetType
         for r in allRoles:
             if r not in roles:
-                warn.append("WARNING: cpp:{} targets a {} (".format(r, txtTargetType))
+                warn.append(f"WARNING: cpp:{r} targets a {txtTargetType} (")
                 if targetType == 'templateParam':
-                    warn.append("WARNING: cpp:{} targets a {} (".format(r, txtTargetType))
-                    warn.append("WARNING: cpp:{} targets a {} (".format(r, txtTargetType))
+                    warn.append(f"WARNING: cpp:{r} targets a {txtTargetType} (")
+                    warn.append(f"WARNING: cpp:{r} targets a {txtTargetType} (")
     warn = sorted(warn)
     for w in ws:
         assert "targets a" in w
@@ -1326,7 +1326,7 @@ not found in `{test}`
 
     for role in (expr_role, texpr_role):
         name = role.name
-        expect = '`{name}` puts the domain and role classes at its root'.format(name=name)
+        expect = f'`{name}` puts the domain and role classes at its root'
         assert {'sig', 'sig-inline', 'cpp', name} <= role.classes, expect
 
     # reference classes
diff --git a/tests/test_ext_apidoc.py b/tests/test_ext_apidoc.py
index 2d427417b..66b106fe6 100644
--- a/tests/test_ext_apidoc.py
+++ b/tests/test_ext_apidoc.py
@@ -318,7 +318,7 @@ def test_toc_all_references_should_exist_pep420_enabled(make_app, apidoc):
         if ref and ref[0] in (':', '#'):
             continue
         found_refs.append(ref)
-        filename = "{}.rst".format(ref)
+        filename = f"{ref}.rst"
         if not (outdir / filename).isfile():
             missing_files.append(filename)
 
@@ -347,7 +347,7 @@ def test_toc_all_references_should_exist_pep420_disabled(make_app, apidoc):
     for ref in refs:
         if ref and ref[0] in (':', '#'):
             continue
-        filename = "{}.rst".format(ref)
+        filename = f"{ref}.rst"
         found_refs.append(ref)
         if not (outdir / filename).isfile():
             missing_files.append(filename)
diff --git a/tests/test_ext_doctest.py b/tests/test_ext_doctest.py
index 6c628904f..e03c12540 100644
--- a/tests/test_ext_doctest.py
+++ b/tests/test_ext_doctest.py
@@ -117,7 +117,7 @@ def test_skipif(app, status, warning):
 def record(directive, part, should_skip):
     global recorded_calls
     recorded_calls[(directive, part, should_skip)] += 1
-    return 'Recorded {} {} {}'.format(directive, part, should_skip)
+    return f'Recorded {directive} {part} {should_skip}'
 
 
 @pytest.mark.sphinx('doctest', testroot='ext-doctest-with-autodoc')
diff --git a/tests/test_ext_imgconverter.py b/tests/test_ext_imgconverter.py
index 8b938a0dc..5132390cf 100644
--- a/tests/test_ext_imgconverter.py
+++ b/tests/test_ext_imgconverter.py
@@ -1,7 +1,6 @@
 """Test sphinx.ext.imgconverter extension."""
 
 import subprocess
-from subprocess import PIPE
 
 import pytest
 
@@ -11,7 +10,7 @@ def if_converter_found(app):
     image_converter = getattr(app.config, 'image_converter', '')
     try:
         if image_converter:
-            subprocess.run([image_converter, '-version'], stdout=PIPE, stderr=PIPE)  # show version
+            subprocess.run([image_converter, '-version'], capture_output=True)  # show version
             return
     except OSError:  # No such file or directory
         pass
diff --git a/tests/test_util_inspect.py b/tests/test_util_inspect.py
index bb43fb30d..753b363da 100644
--- a/tests/test_util_inspect.py
+++ b/tests/test_util_inspect.py
@@ -716,7 +716,7 @@ def test_getdoc_inherited_decorated_method():
             """
 
     class Bar(Foo):
-        @functools.lru_cache()  # noqa: B019
+        @functools.lru_cache  # noqa: B019
         def meth(self):
             # inherited and decorated method
             pass