update black and format

Closes: #342
Pull-request: https://github.com/sqlalchemy/mako/pull/342
Pull-request-sha: 21a068103481410cf4856fb07c19146dc684d460

Change-Id: I9027433ec23ee19c9d9a47015e0327acf409e2d8

26 files changed, 229 insertions, 177 deletions

diff --git a/.github/workflows/run-on-pr.yaml b/.github/workflows/run-on-pr.yaml
index b916836..9b8b545 100644
--- a/.github/workflows/run-on-pr.yaml
+++ b/.github/workflows/run-on-pr.yaml
@@ -10,7 +10,7 @@ on:
 
 jobs:
   run-test:
-    name: ${{ matrix.python-version }}-${{ matrix.os }}
+    name: ${{ matrix.python-version }}-${{ matrix.os }}-${{matrix.tox-env}}
     runs-on: ${{ matrix.os }}
     strategy:
       # run this job using this matrix
@@ -19,6 +19,9 @@ jobs:
           - "ubuntu-latest"
         python-version:
           - "3.10"
+        tox-env:
+          - ""
+          - "-e pep8"
 
       fail-fast: false
 
@@ -40,4 +43,4 @@ jobs:
           pip list
 
       - name: Run tests
-        run: tox
\ No newline at end of file
+        run: tox ${{ matrix.tox-env }}
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index ffacfe7..9fd0eee 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -2,13 +2,12 @@
 # See https://pre-commit.com/hooks.html for more hooks
 repos:
 -   repo: https://github.com/python/black
-    rev: 19.3b0
+    rev: 21.9b0
     hooks:
     -   id: black
-        args: [-l 79]
 
 -   repo: https://github.com/sqlalchemyorg/zimports
-    rev: v0.4.0
+    rev: v0.4.1
     hooks:
     -   id: zimports
 
diff --git a/examples/bench/basic.py b/examples/bench/basic.py
index 15482f6..fc36527 100644
--- a/examples/bench/basic.py
+++ b/examples/bench/basic.py
@@ -1,11 +1,11 @@
 # basic.py - basic benchmarks adapted from Genshi
 # Copyright (C) 2006 Edgewall Software
 # All rights reserved.
-# 
+#
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
 # are met:
-# 
+#
 #  1. Redistributions of source code must retain the above copyright
 #     notice, this list of conditions and the following disclaimer.
 #  2. Redistributions in binary form must reproduce the above copyright
@@ -15,7 +15,7 @@
 #  3. The name of the author may not be used to endorse or promote
 #     products derived from this software without specific prior
 #     written permission.
-# 
+#
 # THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
 # OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 # WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
@@ -33,68 +33,102 @@ import sys
 import timeit
 
 
-__all__ = ['mako', 'mako_inheritance', 'jinja2', 'jinja2_inheritance',
-            'cheetah', 'django', 'myghty', 'genshi', 'kid']
+__all__ = [
+    "mako",
+    "mako_inheritance",
+    "jinja2",
+    "jinja2_inheritance",
+    "cheetah",
+    "django",
+    "myghty",
+    "genshi",
+    "kid",
+]
 
 # Templates content and constants
-TITLE = 'Just a test'
-USER = 'joe'
-ITEMS = ['Number %d' % num for num in range(1, 15)]
+TITLE = "Just a test"
+USER = "joe"
+ITEMS = ["Number %d" % num for num in range(1, 15)]
+
 
 def genshi(dirname, verbose=False):
     from genshi.template import TemplateLoader
+
     loader = TemplateLoader([dirname], auto_reload=False)
-    template = loader.load('template.html')
+    template = loader.load("template.html")
+
     def render():
         data = dict(title=TITLE, user=USER, items=ITEMS)
-        return template.generate(**data).render('xhtml')
+        return template.generate(**data).render("xhtml")
 
     if verbose:
         print(render())
     return render
 
+
 def myghty(dirname, verbose=False):
     from myghty import interp
+
     interpreter = interp.Interpreter(component_root=dirname)
+
     def render():
         data = dict(title=TITLE, user=USER, items=ITEMS)
         buffer = StringIO()
-        interpreter.execute("template.myt", request_args=data, out_buffer=buffer)
+        interpreter.execute(
+            "template.myt", request_args=data, out_buffer=buffer
+        )
         return buffer.getvalue()
+
     if verbose:
         print(render())
     return render
 
+
 def mako(dirname, verbose=False):
     from mako.template import Template
     from mako.lookup import TemplateLookup
+
     lookup = TemplateLookup(directories=[dirname], filesystem_checks=False)
-    template = lookup.get_template('template.html')
+    template = lookup.get_template("template.html")
+
     def render():
         return template.render(title=TITLE, user=USER, list_items=ITEMS)
+
     if verbose:
         print(template.code + " " + render())
     return render
+
+
 mako_inheritance = mako
 
+
 def jinja2(dirname, verbose=False):
     from jinja2 import Environment, FileSystemLoader
+
     env = Environment(loader=FileSystemLoader(dirname))
-    template = env.get_template('template.html')
+    template = env.get_template("template.html")
+
     def render():
         return template.render(title=TITLE, user=USER, list_items=ITEMS)
+
     if verbose:
         print(render())
     return render
+
+
 jinja2_inheritance = jinja2
 
+
 def cheetah(dirname, verbose=False):
     from Cheetah.Template import Template
-    filename = os.path.join(dirname, 'template.tmpl')
+
+    filename = os.path.join(dirname, "template.tmpl")
     template = Template(file=filename)
+
     def render():
-        template.__dict__.update({'title': TITLE, 'user': USER,
-                                  'list_items': ITEMS})
+        template.__dict__.update(
+            {"title": TITLE, "user": USER, "list_items": ITEMS}
+        )
         return template.respond()
 
     if verbose:
@@ -103,30 +137,37 @@ def cheetah(dirname, verbose=False):
         print(render())
     return render
 
+
 def django(dirname, verbose=False):
     from django.conf import settings
-    settings.configure(TEMPLATE_DIRS=[os.path.join(dirname, 'templates')])
+
+    settings.configure(TEMPLATE_DIRS=[os.path.join(dirname, "templates")])
     from django import template, templatetags
     from django.template import loader
-    templatetags.__path__.append(os.path.join(dirname, 'templatetags'))
-    tmpl = loader.get_template('template.html')
+
+    templatetags.__path__.append(os.path.join(dirname, "templatetags"))
+    tmpl = loader.get_template("template.html")
 
     def render():
-        data = {'title': TITLE, 'user': USER, 'items': ITEMS}
+        data = {"title": TITLE, "user": USER, "items": ITEMS}
         return tmpl.render(template.Context(data))
 
     if verbose:
         print(render())
     return render
 
+
 def kid(dirname, verbose=False):
     import kid
+
     kid.path = kid.TemplatePath([dirname])
-    template = kid.Template(file='template.kid')
+    template = kid.Template(file="template.kid")
+
     def render():
-        template = kid.Template(file='template.kid',
-                                title=TITLE, user=USER, items=ITEMS)
-        return template.serialize(output='xhtml')
+        template = kid.Template(
+            file="template.kid", title=TITLE, user=USER, items=ITEMS
+        )
+        return template.serialize(output="xhtml")
 
     if verbose:
         print(render())
@@ -138,42 +179,46 @@ def run(engines, number=2000, verbose=False):
     for engine in engines:
         dirname = os.path.join(basepath, engine)
         if verbose:
-            print('%s:' % engine.capitalize())
-            print('--------------------------------------------------------')
+            print("%s:" % engine.capitalize())
+            print("--------------------------------------------------------")
         else:
-            sys.stdout.write('%s:' % engine.capitalize())
-        t = timeit.Timer(setup='from __main__ import %s; render = %s(r"%s", %s)'
-                                       % (engine, engine, dirname, verbose),
-                                 stmt='render()')
+            sys.stdout.write("%s:" % engine.capitalize())
+        t = timeit.Timer(
+            setup='from __main__ import %s; render = %s(r"%s", %s)'
+            % (engine, engine, dirname, verbose),
+            stmt="render()",
+        )
 
         time = t.timeit(number=number) / number
         if verbose:
-            print('--------------------------------------------------------')
-        print('%.2f ms' % (1000 * time))
+            print("--------------------------------------------------------")
+        print("%.2f ms" % (1000 * time))
         if verbose:
-            print('--------------------------------------------------------')
+            print("--------------------------------------------------------")
 
 
-if __name__ == '__main__':
-    engines = [arg for arg in sys.argv[1:] if arg[0] != '-']
+if __name__ == "__main__":
+    engines = [arg for arg in sys.argv[1:] if arg[0] != "-"]
     if not engines:
         engines = __all__
 
-    verbose = '-v' in sys.argv
+    verbose = "-v" in sys.argv
 
-    if '-p' in sys.argv:
+    if "-p" in sys.argv:
         try:
             import hotshot, hotshot.stats
+
             prof = hotshot.Profile("template.prof")
             benchtime = prof.runcall(run, engines, number=100, verbose=verbose)
             stats = hotshot.stats.load("template.prof")
         except ImportError:
             import cProfile, pstats
+
             stmt = "run(%r, number=%r, verbose=%r)" % (engines, 1000, verbose)
             cProfile.runctx(stmt, globals(), {}, "template.prof")
             stats = pstats.Stats("template.prof")
         stats.strip_dirs()
-        stats.sort_stats('time', 'calls')
+        stats.sort_stats("time", "calls")
         stats.print_stats()
     else:
         run(engines, verbose=verbose)
diff --git a/examples/bench/django/templatetags/bench.py b/examples/bench/django/templatetags/bench.py
index 7bf0abc..1f67937 100644
--- a/examples/bench/django/templatetags/bench.py
+++ b/examples/bench/django/templatetags/bench.py
@@ -3,6 +3,9 @@ from django.utils.html import escape
 
 register = Library()
 
+
 def greeting(name):
-    return 'Hello, %s!' % escape(name)
+    return "Hello, %s!" % escape(name)
+
+
 greeting = register.simple_tag(greeting)
diff --git a/examples/wsgi/run_wsgi.py b/examples/wsgi/run_wsgi.py
index d013074..a98f6c6 100644
--- a/examples/wsgi/run_wsgi.py
+++ b/examples/wsgi/run_wsgi.py
@@ -3,56 +3,56 @@ import cgi, re, os, posixpath, mimetypes
 from mako.lookup import TemplateLookup
 from mako import exceptions
 
-root = './'
+root = "./"
 port = 8000
 
 lookup = TemplateLookup(
-             directories=[root + 'templates', root + 'htdocs'],
-             filesystem_checks=True,
-             module_directory='./modules',
-             # even better would be to use 'charset' in start_response
-             output_encoding='ascii',
-             encoding_errors='replace'
-         )
+    directories=[root + "templates", root + "htdocs"],
+    filesystem_checks=True,
+    module_directory="./modules",
+    # even better would be to use 'charset' in start_response
+    output_encoding="ascii",
+    encoding_errors="replace",
+)
+
 
 def serve(environ, start_response):
     """serves requests using the WSGI callable interface."""
     fieldstorage = cgi.FieldStorage(
-            fp = environ['wsgi.input'],
-            environ = environ,
-            keep_blank_values = True
+        fp=environ["wsgi.input"], environ=environ, keep_blank_values=True
     )
     d = dict([(k, getfield(fieldstorage[k])) for k in fieldstorage])
 
-    uri = environ.get('PATH_INFO', '/')
+    uri = environ.get("PATH_INFO", "/")
     if not uri:
-        uri = '/index.html'
+        uri = "/index.html"
     else:
-        uri = re.sub(r'^/$', '/index.html', uri)
+        uri = re.sub(r"^/$", "/index.html", uri)
 
-    if re.match(r'.*\.html$', uri):
+    if re.match(r".*\.html$", uri):
         try:
             template = lookup.get_template(uri)
         except exceptions.TopLevelLookupException:
             start_response("404 Not Found", [])
             return [str.encode("Cant find template '%s'" % uri)]
 
-        start_response("200 OK", [('Content-type','text/html')])
+        start_response("200 OK", [("Content-type", "text/html")])
 
         try:
             return [template.render(**d)]
         except:
             return [exceptions.html_error_template().render()]
     else:
-        u = re.sub(r'^\/+', '', uri)
+        u = re.sub(r"^\/+", "", uri)
         filename = os.path.join(root, u)
         if os.path.isfile(filename):
-            start_response("200 OK", [('Content-type',guess_type(uri))])
-            return [open(filename, 'rb').read()]
+            start_response("200 OK", [("Content-type", guess_type(uri))])
+            return [open(filename, "rb").read()]
         else:
             start_response("404 Not Found", [])
             return [str.encode("File not found: '%s'" % filename)]
- 
+
+
 def getfield(f):
     """convert values from cgi.Field objects to plain values."""
     if isinstance(f, list):
@@ -60,8 +60,10 @@ def getfield(f):
     else:
         return f.value
 
+
 extensions_map = mimetypes.types_map.copy()
 
+
 def guess_type(path):
     """return a mimetype for the given path based on file extension."""
     base, ext = posixpath.splitext(path)
@@ -71,10 +73,12 @@ def guess_type(path):
     if ext in extensions_map:
         return extensions_map[ext]
     else:
-        return 'text/html'
- 
-if __name__ == '__main__':
+        return "text/html"
+
+
+if __name__ == "__main__":
     import wsgiref.simple_server
-    server = wsgiref.simple_server.make_server('', port, serve)
+
+    server = wsgiref.simple_server.make_server("", port, serve)
     print("Server listening on port %d" % port)
     server.serve_forever()
diff --git a/mako/codegen.py b/mako/codegen.py
index 7f1c8c3..c897f0f 100644
--- a/mako/codegen.py
+++ b/mako/codegen.py
@@ -43,7 +43,7 @@ def compile(  # noqa
     reserved_names=frozenset(),
 ):
     """Generate module source code given a parsetree node,
-      uri, and optional source filename"""
+    uri, and optional source filename"""
 
     buf = util.FastEncodingBuffer()
 
@@ -99,7 +99,7 @@ class _CompileContext:
 class _GenerateRenderMethod:
 
     """A template visitor object which generates the
-       full module source for a template.
+    full module source for a template.
 
     """
 
@@ -702,7 +702,7 @@ class _GenerateRenderMethod:
         toplevel=False,
     ):
         """write a post-function decorator to replace a rendering
-            callable with a cached version of itself."""
+        callable with a cached version of itself."""
 
         self.printer.writeline("__M_%s = %s" % (name, name))
         cachekey = node_or_pagetag.parsed_attributes.get(
@@ -1084,7 +1084,7 @@ class _Identifiers:
 
     def branch(self, node, **kwargs):
         """create a new Identifiers for a new Node, with
-          this Identifiers as the parent."""
+        this Identifiers as the parent."""
 
         return _Identifiers(self.compiler, node, self, **kwargs)
 
@@ -1109,7 +1109,7 @@ class _Identifiers:
 
     def check_declared(self, node):
         """update the state of this Identifiers with the undeclared
-            and declared identifiers of the given node."""
+        and declared identifiers of the given node."""
 
         for ident in node.undeclared_identifiers():
             if ident != "context" and ident not in self.declared.union(
diff --git a/mako/exceptions.py b/mako/exceptions.py
index ec2de81..a0a5fec 100644
--- a/mako/exceptions.py
+++ b/mako/exceptions.py
@@ -139,8 +139,7 @@ class RichTraceback:
 
     @property
     def reverse_traceback(self):
-        """Return the same data as traceback, except in reverse order.
-        """
+        """Return the same data as traceback, except in reverse order."""
 
         return list(self._get_reformatted_records(self.reverse_records))
 
diff --git a/mako/lexer.py b/mako/lexer.py
index 306ae4b..953c0a0 100644
--- a/mako/lexer.py
+++ b/mako/lexer.py
@@ -176,8 +176,8 @@ class Lexer:
 
     def decode_raw_stream(self, text, decode_raw, known_encoding, filename):
         """given string/unicode or bytes/string, determine encoding
-           from magic encoding comment, return body as unicode
-           or raw if decode_raw=False
+        from magic encoding comment, return body as unicode
+        or raw if decode_raw=False
 
         """
         if isinstance(text, str):
@@ -312,7 +312,7 @@ class Lexer:
             if not match:
                 raise exceptions.SyntaxException(
                     "Unclosed tag: <%%%s>" % self.tag[-1].keyword,
-                    **self.exception_kwargs
+                    **self.exception_kwargs,
                 )
             self.append_node(parsetree.Text, match.group(1))
             return self.match_tag_end()
@@ -434,7 +434,7 @@ class Lexer:
             if not m2:
                 raise exceptions.SyntaxException(
                     "Invalid control line: '%s'" % text,
-                    **self.exception_kwargs
+                    **self.exception_kwargs,
                 )
             isend, keyword = m2.group(1, 2)
             isend = isend is not None
@@ -442,15 +442,14 @@ class Lexer:
             if isend:
                 if not len(self.control_line):
                     raise exceptions.SyntaxException(
-                        "No starting keyword '%s' for '%s'"
-                        % (keyword, text),
-                        **self.exception_kwargs
+                        "No starting keyword '%s' for '%s'" % (keyword, text),
+                        **self.exception_kwargs,
                     )
                 elif self.control_line[-1].keyword != keyword:
                     raise exceptions.SyntaxException(
                         "Keyword '%s' doesn't match keyword '%s'"
                         % (text, self.control_line[-1].keyword),
-                        **self.exception_kwargs
+                        **self.exception_kwargs,
                     )
             self.append_node(parsetree.ControlLine, keyword, isend, text)
         else:
diff --git a/mako/lookup.py b/mako/lookup.py
index 06dee89..17cef8e 100644
--- a/mako/lookup.py
+++ b/mako/lookup.py
@@ -30,7 +30,7 @@ class TemplateCollection:
     :class:`.TemplateCollection` is an abstract class,
     with the usual default implementation being :class:`.TemplateLookup`.
 
-     """
+    """
 
     def has_template(self, uri):
         """Return ``True`` if this :class:`.TemplateLookup` is
@@ -64,7 +64,7 @@ class TemplateCollection:
 
     def filename_to_uri(self, uri, filename):
         """Convert the given ``filename`` to a URI relative to
-           this :class:`.TemplateCollection`."""
+        this :class:`.TemplateCollection`."""
 
         return uri
 
@@ -274,7 +274,7 @@ class TemplateLookup(TemplateCollection):
 
     def filename_to_uri(self, filename):
         """Convert the given ``filename`` to a URI relative to
-           this :class:`.TemplateCollection`."""
+        this :class:`.TemplateCollection`."""
 
         try:
             return self._uri_cache[filename]
@@ -285,7 +285,7 @@ class TemplateLookup(TemplateCollection):
 
     def _relativeize(self, filename):
         """Return the portion of a filename that is 'relative'
-           to the directories in this lookup.
+        to the directories in this lookup.
 
         """
 
diff --git a/mako/parsetree.py b/mako/parsetree.py
index 7ec0c1c..c1629d9 100644
--- a/mako/parsetree.py
+++ b/mako/parsetree.py
@@ -106,11 +106,13 @@ class ControlLine(Node):
         """return true if the given keyword is a ternary keyword
         for this ControlLine"""
 
-        return keyword in {
+        cases = {
             "if": {"else", "elif"},
             "try": {"except", "finally"},
             "for": {"else"},
-        }.get(self.keyword, [])
+        }
+
+        return keyword in cases.get(self.keyword, set())
 
     def __repr__(self):
         return "ControlLine(%r, %r, %r, %r)" % (
diff --git a/mako/pygen.py b/mako/pygen.py
index bf8811c..46b0b52 100644
--- a/mako/pygen.py
+++ b/mako/pygen.py
@@ -107,9 +107,7 @@ class PythonPrinter:
             # module wont compile.
             if len(self.indent_detail) == 0:
                 # TODO: no coverage here
-                raise exceptions.MakoException(
-                    "Too many whitespace closures"
-                )
+                raise exceptions.MakoException("Too many whitespace closures")
             self.indent_detail.pop()
 
         if line is None:
diff --git a/mako/pyparser.py b/mako/pyparser.py
index c626622..2a1ba5f 100644
--- a/mako/pyparser.py
+++ b/mako/pyparser.py
@@ -161,7 +161,7 @@ class FindIdentifiers(_ast_util.NodeVisitor):
                     "names must be explicitly declared.  Please use the "
                     "form 'from <modulename> import <name1>, <name2>, "
                     "...' instead.",
-                    **self.exception_kwargs
+                    **self.exception_kwargs,
                 )
             else:
                 self._add_declared(name.name)
diff --git a/mako/runtime.py b/mako/runtime.py
index 28186a9..f5dbe1a 100644
--- a/mako/runtime.py
+++ b/mako/runtime.py
@@ -24,7 +24,7 @@ class Context:
     See :ref:`runtime_toplevel` for detail on the usage of
     :class:`.Context`.
 
-     """
+    """
 
     def __init__(self, buffer, **data):
         self._buffer_stack = [buffer]
@@ -339,8 +339,7 @@ class LoopContext:
         return bool(self.index % 2)
 
     def cycle(self, *values):
-        """Cycle through values as the loop progresses.
-        """
+        """Cycle through values as the loop progresses."""
         if not values:
             raise ValueError("You must provide values to cycle through")
         return values[self.index % len(values)]
@@ -363,19 +362,19 @@ class _NSAttr:
 class Namespace:
 
     """Provides access to collections of rendering methods, which
-      can be local, from other templates, or from imported modules.
+    can be local, from other templates, or from imported modules.
 
-      To access a particular rendering method referenced by a
-      :class:`.Namespace`, use plain attribute access:
+    To access a particular rendering method referenced by a
+    :class:`.Namespace`, use plain attribute access:
 
-      .. sourcecode:: mako
+    .. sourcecode:: mako
 
-        ${some_namespace.foo(x, y, z)}
+      ${some_namespace.foo(x, y, z)}
 
-      :class:`.Namespace` also contains several built-in attributes
-      described here.
+    :class:`.Namespace` also contains several built-in attributes
+    described here.
 
-      """
+    """
 
     def __init__(
         self,
diff --git a/mako/template.py b/mako/template.py
index df2a7ac..bbbe73c 100644
--- a/mako/template.py
+++ b/mako/template.py
@@ -483,17 +483,17 @@ class ModuleTemplate(Template):
 
     """A Template which is constructed given an existing Python module.
 
-       e.g.::
+    e.g.::
 
-            t = Template("this is a template")
-            f = file("mymodule.py", "w")
-            f.write(t.code)
-            f.close()
+         t = Template("this is a template")
+         f = file("mymodule.py", "w")
+         f.write(t.code)
+         f.close()
 
-            import mymodule
+         import mymodule
 
-            t = ModuleTemplate(mymodule)
-            print(t.render())
+         t = ModuleTemplate(mymodule)
+         print(t.render())
 
     """
 
@@ -579,7 +579,7 @@ class ModuleInfo:
     memory, provides reverse lookups of template source, module
     source code based on a module's identifier.
 
-     """
+    """
 
     _modules = weakref.WeakValueDictionary()
 
@@ -642,9 +642,7 @@ class ModuleInfo:
         elif self.module._source_encoding and not isinstance(
             self.template_source, str
         ):
-            return self.template_source.decode(
-                self.module._source_encoding
-            )
+            return self.template_source.decode(self.module._source_encoding)
         else:
             return self.template_source
 
diff --git a/test/__init__.py b/test/__init__.py
index 6c5047a..9b85cdf 100644
--- a/test/__init__.py
+++ b/test/__init__.py
@@ -102,9 +102,10 @@ def raises(except_cls, message=None):
         success = False
     except except_cls as e:
         if message:
-            assert re.search(
-                message, str(e), re.UNICODE
-            ), "%r !~ %s" % (message, e)
+            assert re.search(message, str(e), re.UNICODE), "%r !~ %s" % (
+                message,
+                e,
+            )
             print(str(e).encode("utf-8"))
         success = True
 
@@ -168,7 +169,7 @@ def requires_no_pygments_exceptions(fn):
 
 class PlainCacheImpl(CacheImpl):
     """Simple memory cache impl so that tests which
-    use caching can run without beaker.  """
+    use caching can run without beaker."""
 
     def __init__(self, cache):
         self.cache = cache
diff --git a/test/ext/test_babelplugin.py b/test/ext/test_babelplugin.py
index bf21aa2..a69d884 100644
--- a/test/ext/test_babelplugin.py
+++ b/test/ext/test_babelplugin.py
@@ -105,7 +105,7 @@ class ExtractMakoTestCase(TemplateTest):
         message = next(
             extract(mako_tmpl, set(["_", None]), [], {"encoding": "utf-8"})
         )
-        assert message == (1, "_", u"K\xf6ln", [])
+        assert message == (1, "_", "K\xf6ln", [])
 
     @skip()
     def test_extract_cp1251(self):
@@ -117,4 +117,4 @@ class ExtractMakoTestCase(TemplateTest):
             extract(mako_tmpl, set(["_", None]), [], {"encoding": "cp1251"})
         )
         # "test" in Rusian. File encoding is cp1251 (aka "windows-1251")
-        assert message == (1, "_", u"\u0442\u0435\u0441\u0442", [])
+        assert message == (1, "_", "\u0442\u0435\u0441\u0442", [])
diff --git a/test/ext/test_linguaplugin.py b/test/ext/test_linguaplugin.py
index f505759..53d7073 100644
--- a/test/ext/test_linguaplugin.py
+++ b/test/ext/test_linguaplugin.py
@@ -55,9 +55,9 @@ class ExtractMakoTestCase(TemplateTest):
                 ("Goodbye, really!", None),
                 ("P.S. byebye", None),
                 ("Top", None),
-                (u"foo", None),
+                ("foo", None),
                 ("hoho", None),
-                (u"bar", None),
+                ("bar", None),
                 ("Inside a p tag", None),
                 ("Later in a p tag", None),
                 ("No action at a distance.", None),
diff --git a/test/templates/foo/modtest.html.py b/test/templates/foo/modtest.html.py
index e6fc8d8..7a73e55 100644
--- a/test/templates/foo/modtest.html.py
+++ b/test/templates/foo/modtest.html.py
@@ -1,25 +1,24 @@
 from mako import runtime, filters, cache
+
 UNDEFINED = runtime.UNDEFINED
 __M_dict_builtin = dict
 __M_locals_builtin = locals
 _magic_number = 5
 _modified_time = 1267565427.7968459
-_template_filename='/Users/classic/dev/mako/test/templates/modtest.html'
-_template_uri='/modtest.html'
-_template_cache=cache.Cache(__name__, _modified_time)
-_source_encoding=None
+_template_filename = "/Users/classic/dev/mako/test/templates/modtest.html"
+_template_uri = "/modtest.html"
+_template_cache = cache.Cache(__name__, _modified_time)
+_source_encoding = None
 _exports = []
 
 
-def render_body(context,**pageargs):
+def render_body(context, **pageargs):
     context.caller_stack._push_frame()
     try:
         __M_locals = __M_dict_builtin(pageargs=pageargs)
         __M_writer = context.writer()
         # SOURCE LINE 1
-        __M_writer('this is a test')
-        return ''
+        __M_writer("this is a test")
+        return ""
     finally:
         context.caller_stack._pop_frame()
-
-
diff --git a/test/templates/subdir/foo/modtest.html.py b/test/templates/subdir/foo/modtest.html.py
index b0f50c7..8b3a73b 100644
--- a/test/templates/subdir/foo/modtest.html.py
+++ b/test/templates/subdir/foo/modtest.html.py
@@ -1,25 +1,26 @@
 from mako import runtime, filters, cache
+
 UNDEFINED = runtime.UNDEFINED
 __M_dict_builtin = dict
 __M_locals_builtin = locals
 _magic_number = 5
 _modified_time = 1267565427.799504
-_template_filename='/Users/classic/dev/mako/test/templates/subdir/modtest.html'
-_template_uri='/subdir/modtest.html'
-_template_cache=cache.Cache(__name__, _modified_time)
-_source_encoding=None
+_template_filename = (
+    "/Users/classic/dev/mako/test/templates/subdir/modtest.html"
+)
+_template_uri = "/subdir/modtest.html"
+_template_cache = cache.Cache(__name__, _modified_time)
+_source_encoding = None
 _exports = []
 
 
-def render_body(context,**pageargs):
+def render_body(context, **pageargs):
     context.caller_stack._push_frame()
     try:
         __M_locals = __M_dict_builtin(pageargs=pageargs)
         __M_writer = context.writer()
         # SOURCE LINE 1
-        __M_writer('this is a test')
-        return ''
+        __M_writer("this is a test")
+        return ""
     finally:
         context.caller_stack._pop_frame()
-
-
diff --git a/test/test_ast.py b/test/test_ast.py
index daa7c6e..0f30c5a 100644
--- a/test/test_ast.py
+++ b/test/test_ast.py
@@ -234,7 +234,7 @@ import x as bar
             exceptions.CompileException,
             ast.PythonCode,
             code,
-            **exception_kwargs
+            **exception_kwargs,
         )
 
     def test_python_fragment(self):
diff --git a/test/test_exceptions.py b/test/test_exceptions.py
index b0e2bb1..dc3b735 100644
--- a/test/test_exceptions.py
+++ b/test/test_exceptions.py
@@ -77,13 +77,12 @@ ${'привет'}
         except exceptions.CompileException:
             html_error = exceptions.html_error_template().render()
             assert (
-                (
-                    "CompileException: Fragment &#39;if 2 == 2: /an "
-                    "error&#39; is not a partial control statement "
-                    "at line: 2 char: 1"
-                ).encode(sys.getdefaultencoding(), "htmlentityreplace")
-                in html_error
-            )
+                "CompileException: Fragment &#39;if 2 == 2: /an "
+                "error&#39; is not a partial control statement "
+                "at line: 2 char: 1"
+            ).encode(
+                sys.getdefaultencoding(), "htmlentityreplace"
+            ) in html_error
 
             assert (
                 "".encode(sys.getdefaultencoding(), "htmlentityreplace")
@@ -111,13 +110,12 @@ ${'привет'}
         except exceptions.CompileException:
             html_error = exceptions.html_error_template().render()
             assert (
-                (
-                    "CompileException: Fragment &#39;if 2 == 2: /an "
-                    "error&#39; is not a partial control statement "
-                    "at line: 2 char: 1"
-                ).encode(sys.getdefaultencoding(), "htmlentityreplace")
-                in html_error
-            )
+                "CompileException: Fragment &#39;if 2 == 2: /an "
+                "error&#39; is not a partial control statement "
+                "at line: 2 char: 1"
+            ).encode(
+                sys.getdefaultencoding(), "htmlentityreplace"
+            ) in html_error
             assert (
                 "${&#39;привет&#39;}".encode(
                     sys.getdefaultencoding(), "htmlentityreplace"
@@ -154,9 +152,7 @@ ${'привет'}
             raise RuntimeError("日本")
         except:
             html_error = exceptions.html_error_template().render()
-            assert (
-                "RuntimeError: 日本".encode("ascii", "ignore") in html_error
-            )
+            assert "RuntimeError: 日本".encode("ascii", "ignore") in html_error
 
     @requires_pygments_14
     def test_format_exceptions_pygments(self):
@@ -208,7 +204,7 @@ ${foobar}
     @requires_pygments_14
     def test_utf8_format_exceptions_pygments(self):
         """test that htmlentityreplace formatting is applied to
-           exceptions reported with format_exceptions=True"""
+        exceptions reported with format_exceptions=True"""
 
         l = TemplateLookup(format_exceptions=True)
         l.put_string(
@@ -222,7 +218,7 @@ ${foobar}
     @requires_no_pygments_exceptions
     def test_utf8_format_exceptions_no_pygments(self):
         """test that htmlentityreplace formatting is applied to
-           exceptions reported with format_exceptions=True"""
+        exceptions reported with format_exceptions=True"""
 
         l = TemplateLookup(format_exceptions=True)
         l.put_string(
diff --git a/test/test_filters.py b/test/test_filters.py
index 4def5f8..7aa7662 100644
--- a/test/test_filters.py
+++ b/test/test_filters.py
@@ -74,7 +74,7 @@ class FilterTest(TemplateTest):
         )
 
         eq_(
-            flatten_result(t.render(bar=u"酒吧bar")),
+            flatten_result(t.render(bar="酒吧bar")),
             "http://example.com/?bar=%E9%85%92%E5%90%A7bar&v=1",
         )
 
diff --git a/test/test_template.py b/test/test_template.py
index 715bc4c..f2ca6b4 100644
--- a/test/test_template.py
+++ b/test/test_template.py
@@ -332,7 +332,7 @@ quand une drôle de petite voix m’a réveillé. Elle disait:
 
     def test_input_encoding(self):
         """test the 'input_encoding' flag on Template, and that unicode
-            objects arent double-decoded"""
+        objects arent double-decoded"""
 
         self._do_memory_test(
             ("hello ${f('śląsk')}"),
@@ -927,15 +927,18 @@ class ControlTest(TemplateTest):
     %endfor
 """
         )
-        assert result_lines(
-            t.render(
-                y=[
-                    {"test": "one"},
-                    {"foo": "bar"},
-                    {"foo": "bar", "test": "two"},
-                ]
+        assert (
+            result_lines(
+                t.render(
+                    y=[
+                        {"test": "one"},
+                        {"foo": "bar"},
+                        {"foo": "bar", "test": "two"},
+                    ]
+                )
             )
-        ) == ["yes x has test", "no x does not have test", "yes x has test"]
+            == ["yes x has test", "no x does not have test", "yes x has test"]
+        )
 
     def test_blank_control_1(self):
         self._do_memory_test(
diff --git a/test/test_tgplugin.py b/test/test_tgplugin.py
index d69ddf9..9b8055f 100644
--- a/test/test_tgplugin.py
+++ b/test/test_tgplugin.py
@@ -46,6 +46,6 @@ class TestTGPlugin(TemplateTest):
         assert result_lines(tl.render({}, template="/index.html")) == [
             "this is index"
         ]
-        assert result_lines(
-            tl.render({}, template=("/index.html"))
-        ) == ["this is index"]
+        assert result_lines(tl.render({}, template=("/index.html"))) == [
+            "this is index"
+        ]
diff --git a/test/test_util.py b/test/test_util.py
index 78096c1..2646300 100644
--- a/test/test_util.py
+++ b/test/test_util.py
@@ -29,7 +29,7 @@ class UtilTest(unittest.TestCase):
         eq_(buf.getvalue(), "string c string d")
 
     def test_fast_buffer_encoded(self):
-        s = ("drôl m’a rée « S’il")
+        s = "drôl m’a rée « S’il"
         buf = util.FastEncodingBuffer(encoding="utf-8")
         buf.write(s[0:10])
         buf.write(s[10:])
diff --git a/tox.ini b/tox.ini
index 2478967..d8edd3c 100644
--- a/tox.ini
+++ b/tox.ini
@@ -30,4 +30,7 @@ deps=
       pydocstyle<4.0.0
       # used by flake8-rst-docstrings
       pygments
-commands = flake8 ./mako/ ./test/ setup.py --exclude test/templates,test/foo  {posargs}
+      black==21.9b0
+commands =
+    flake8 ./mako/ ./test/ setup.py --exclude test/templates,test/foo  {posargs}
+    black --check .