really drop python<=3.7

demos/chat/chatdemo.py

@@ -25,7 +25,7 @@
 define("debug", default=True, help="run in debug mode")
 
 
-class MessageBuffer(object):
+class MessageBuffer:
     def __init__(self):
         # cond is notified whenever the message cache is updated
         self.cond = tornado.locks.Condition()

demos/webspider/webspider.py

@@ -74,7 +74,7 @@ async def worker():
             try:
                 await fetch_url(url)
             except Exception as e:
-                print("Exception: %s %s" % (e, url))
+                print("Exception: {} {}".format(e, url))
                 dead.add(url)
             finally:
                 q.task_done()

maint/benchmark/chunk_benchmark.py

@@ -14,23 +14,23 @@
 except NameError:
     xrange = range
 
-define('port', default=8888)
-define('num_chunks', default=1000)
-define('chunk_size', default=2048)
+define("port", default=8888)
+define("num_chunks", default=1000)
+define("chunk_size", default=2048)
 
 
 class ChunkHandler(RequestHandler):
     def get(self):
         for i in xrange(options.num_chunks):
-            self.write('A' * options.chunk_size)
+            self.write("A" * options.chunk_size)
             self.flush()
         self.finish()
 
 
 def main():
     parse_command_line()
-    app = Application([('/', ChunkHandler)])
-    app.listen(options.port, address='127.0.0.1')
+    app = Application([("/", ChunkHandler)])
+    app.listen(options.port, address="127.0.0.1")
 
     def callback(response):
         response.rethrow()
@@ -40,16 +40,14 @@ def callback(response):
 
     logging.warning("Starting fetch with curl client")
     curl_client = CurlAsyncHTTPClient()
-    curl_client.fetch('http://localhost:%d/' % options.port,
-                      callback=callback)
+    curl_client.fetch("http://localhost:%d/" % options.port, callback=callback)
     IOLoop.current().start()
 
     logging.warning("Starting fetch with simple client")
     simple_client = SimpleAsyncHTTPClient()
-    simple_client.fetch('http://localhost:%d/' % options.port,
-                        callback=callback)
+    simple_client.fetch("http://localhost:%d/" % options.port, callback=callback)
     IOLoop.current().start()
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     main()

maint/benchmark/gen_benchmark.py

@@ -9,7 +9,7 @@
 from tornado import gen
 from tornado.options import options, define, parse_command_line
 
-define('num', default=10000, help='number of iterations')
+define("num", default=10000, help="number of iterations")
 
 # These benchmarks are delicate.  They hit various fast-paths in the gen
 # machinery in order to stay synchronous so we don't need an IOLoop.
@@ -43,11 +43,11 @@ def main():
     parse_command_line()
     t = Timer(e1)
     results = t.timeit(options.num) / options.num
-    print('engine: %0.3f ms per iteration' % (results * 1000))
+    print("engine: %0.3f ms per iteration" % (results * 1000))
     t = Timer(c1)
     results = t.timeit(options.num) / options.num
-    print('coroutine: %0.3f ms per iteration' % (results * 1000))
+    print("coroutine: %0.3f ms per iteration" % (results * 1000))
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     main()

maint/benchmark/parsing_benchmark.py

@@ -99,14 +99,15 @@ def main():
     except ValueError:
         known_benchmarks = [benchmark.value for benchmark in Benchmark]
         print(
-            "Unknown benchmark: '{}', supported values are: {}"
-            .format(options.benchmark, ", ".join(known_benchmarks))
+            "Unknown benchmark: '{}', supported values are: {}".format(
+                options.benchmark, ", ".join(known_benchmarks)
+            )
         )
         return
 
     for _ in range(options.num_runs):
         func()
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     main()

maint/benchmark/template_benchmark.py

@@ -9,16 +9,18 @@
 from tornado.options import options, define, parse_command_line
 from tornado.template import Template
 
-define('num', default=100, help='number of iterations')
-define('dump', default=False, help='print template generated code and exit')
+define("num", default=100, help="number of iterations")
+define("dump", default=False, help="print template generated code and exit")
 
 context = {
-    'page_title': 'mitsuhiko\'s benchmark',
-    'table': [dict(a=1, b=2, c=3, d=4, e=5,
-                   f=6, g=7, h=8, i=9, j=10) for x in range(1000)]
+    "page_title": "mitsuhiko's benchmark",
+    "table": [
+        dict(a=1, b=2, c=3, d=4, e=5, f=6, g=7, h=8, i=9, j=10) for x in range(1000)
+    ],
 }
 
-tmpl = Template("""\
+tmpl = Template(
+    """\
 <!doctype html>
 <html>
   <head>
@@ -50,7 +52,8 @@
     </div>
   </body>
 </html>\
-""")
+"""
+)
 
 
 def render():
@@ -64,8 +67,8 @@ def main():
         sys.exit(0)
     t = Timer(render)
     results = t.timeit(options.num) / options.num
-    print('%0.3f ms per iteration' % (results * 1000))
+    print("%0.3f ms per iteration" % (results * 1000))
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     main()

maint/scripts/custom_fixers/fix_future_imports.py

@@ -1,5 +1,6 @@
 """Updates all source files to import the same set of __future__ directives.
 """
+
 from lib2to3 import fixer_base
 from lib2to3 import pytree
 from lib2to3.pgen2 import token
@@ -20,10 +21,16 @@ def start_tree(self, tree, filename):
         self.found_future_import = False
 
     def new_future_import(self, old):
-        new = FromImport("__future__",
-                         [Name("absolute_import", prefix=" "), Comma(),
-                          Name("division", prefix=" "), Comma(),
-                          Name("print_function", prefix=" ")])
+        new = FromImport(
+            "__future__",
+            [
+                Name("absolute_import", prefix=" "),
+                Comma(),
+                Name("division", prefix=" "),
+                Comma(),
+                Name("print_function", prefix=" "),
+            ],
+        )
         if old is not None:
             new.prefix = old.prefix
         return new

maint/scripts/custom_fixers/fix_unicode_literal.py

@@ -16,4 +16,4 @@ class FixUnicodeLiteral(fixer_base.BaseFix):
 
     def transform(self, node, results):
         arg = results["arg"]
-        node.replace(String('u' + arg.value, prefix=node.prefix))
+        node.replace(String("u" + arg.value, prefix=node.prefix))

maint/scripts/test_resolvers.py

@@ -17,42 +17,45 @@
 except ImportError:
     pycares = None
 
-define('family', default='unspec',
-       help='Address family to query: unspec, inet, or inet6')
+define(
+    "family", default="unspec", help="Address family to query: unspec, inet, or inet6"
+)
 
 
 @gen.coroutine
 def main():
     args = parse_command_line()
 
     if not args:
-        args = ['localhost', 'www.google.com',
-                'www.facebook.com', 'www.dropbox.com']
+        args = ["localhost", "www.google.com", "www.facebook.com", "www.dropbox.com"]
 
     resolvers = [Resolver(), ThreadedResolver(), DefaultExecutorResolver()]
 
     if twisted is not None:
         from tornado.platform.twisted import TwistedResolver
+
         resolvers.append(TwistedResolver())
 
     if pycares is not None:
         from tornado.platform.caresresolver import CaresResolver
+
         resolvers.append(CaresResolver())
 
     family = {
-        'unspec': socket.AF_UNSPEC,
-        'inet': socket.AF_INET,
-        'inet6': socket.AF_INET6,
+        "unspec": socket.AF_UNSPEC,
+        "inet": socket.AF_INET,
+        "inet6": socket.AF_INET6,
     }[options.family]
 
     for host in args:
-        print('Resolving %s' % host)
+        print("Resolving %s" % host)
         for resolver in resolvers:
             addrinfo = yield resolver.resolve(host, 80, family)
-            print('%s: %s' % (resolver.__class__.__name__,
-                              pprint.pformat(addrinfo)))
+            print(
+                "{}: {}".format(resolver.__class__.__name__, pprint.pformat(addrinfo))
+            )
         print()
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     IOLoop.instance().run_sync(main)

maint/test/cython/cythonapp_test.py

@@ -19,17 +19,19 @@ def test_decorated_coroutine(self):
 
 class CythonArgReplacerTest(unittest.TestCase):
     def test_arg_replacer_function(self):
-        replacer = ArgReplacer(cythonapp.function_with_args, 'two')
-        args = (1, 'old', 3)
+        replacer = ArgReplacer(cythonapp.function_with_args, "two")
+        args = (1, "old", 3)
         kwargs = {}
-        self.assertEqual(replacer.get_old_value(args, kwargs), 'old')
-        self.assertEqual(replacer.replace('new', args, kwargs),
-                         ('old', [1, 'new', 3], {}))
+        self.assertEqual(replacer.get_old_value(args, kwargs), "old")
+        self.assertEqual(
+            replacer.replace("new", args, kwargs), ("old", [1, "new", 3], {})
+        )
 
     def test_arg_replacer_method(self):
-        replacer = ArgReplacer(cythonapp.AClass().method_with_args, 'two')
-        args = (1, 'old', 3)
+        replacer = ArgReplacer(cythonapp.AClass().method_with_args, "two")
+        args = (1, "old", 3)
         kwargs = {}
-        self.assertEqual(replacer.get_old_value(args, kwargs), 'old')
-        self.assertEqual(replacer.replace('new', args, kwargs),
-                         ('old', [1, 'new', 3], {}))
+        self.assertEqual(replacer.get_old_value(args, kwargs), "old")
+        self.assertEqual(
+            replacer.replace("new", args, kwargs), ("old", [1, "new", 3], {})
+        )

maint/test/cython/setup.py

@@ -8,11 +8,11 @@
 if Cython is None:
     ext_modules = None
 else:
-    ext_modules = Cython.Build.cythonize('cythonapp.pyx')
+    ext_modules = Cython.Build.cythonize("cythonapp.pyx")
 
 setup(
-    name='cythonapp',
-    py_modules=['cythonapp_test', 'pythonmodule'],
+    name="cythonapp",
+    py_modules=["cythonapp_test", "pythonmodule"],
     ext_modules=ext_modules,
-    setup_requires='Cython>=0.23.1',
+    setup_requires="Cython>=0.23.1",
 )