really drop python<=3.7 support

Filter all code over `pyupgrade --py38-plus`.

Signed-off-by: Tomasz Kłoczko <kloczek@github.com>

docs/conf.py

@@ -9,7 +9,7 @@
 version_file = os.path.join(os.path.dirname(os.path.dirname(__file__)),
                             'uvloop', '_version.py')
 
-with open(version_file, 'r') as f:
+with open(version_file) as f:
     for line in f:
         if line.startswith('__version__ ='):
             _, _, version = line.partition('=')

examples/bench/echoclient.py

@@ -45,7 +45,7 @@
         addr = args.addr.split(':')
         addr[1] = int(addr[1])
         addr = tuple(addr)
-    print('will connect to: {}'.format(addr))
+    print(f'will connect to: {addr}')
 
     MSGSIZE = args.msize
     REQSIZE = MSGSIZE * args.mpr

examples/bench/echoserver.py

@@ -138,7 +138,7 @@ async def print_debug(loop):
         addr[1] = int(addr[1])
         addr = tuple(addr)
 
-    print('serving on: {}'.format(addr))
+    print(f'serving on: {addr}')
 
     server_context = None
     if args.ssl:

examples/bench/rlserver.py

@@ -71,7 +71,7 @@ async def print_debug(loop):
         addr = tuple(addr)
 
     print('readline performance test')
-    print('serving on: {}'.format(addr))
+    print(f'serving on: {addr}')
 
     print('using asyncio/streams')
     if unix:

setup.py

@@ -26,7 +26,7 @@
 MODULES_CFLAGS = [os.getenv('UVLOOP_OPT_CFLAGS', '-O2')]
 _ROOT = pathlib.Path(__file__).parent
 LIBUV_DIR = str(_ROOT / 'vendor' / 'libuv')
-LIBUV_BUILD_DIR = str(_ROOT / 'build' / 'libuv-{}'.format(MACHINE))
+LIBUV_BUILD_DIR = str(_ROOT / 'build' / f'libuv-{MACHINE}')
 
 
 def _libuv_build_env():
@@ -176,7 +176,7 @@ def build_libuv(self):
             cmd,
             cwd=LIBUV_BUILD_DIR, env=env, check=True)
 
-        j_flag = '-j{}'.format(os.cpu_count() or 1)
+        j_flag = f'-j{os.cpu_count() or 1}'
         c_flag = "CFLAGS={}".format(env['CFLAGS'])
         subprocess.run(
             ['make', j_flag, c_flag],

tests/test_aiohttp.py

@@ -95,7 +95,7 @@ async def on_shutdown(app):
         async def client():
             async with aiohttp.ClientSession() as client:
                 async with client.ws_connect(
-                        'http://127.0.0.1:{}'.format(port)) as ws:
+                        f'http://127.0.0.1:{port}') as ws:
                     await ws.send_str("hello")
                     async for msg in ws:
                         assert msg.data == "hello"

tests/test_context.py

@@ -202,16 +202,16 @@ def fut_on_done(fut):
             for j in range(2):
                 fut = self.loop.create_future()
                 fut.add_done_callback(fut_on_done)
-                cvar.set('yes{}'.format(j))
+                cvar.set(f'yes{j}')
                 self.loop.call_soon(fut.set_result, None)
                 await fut
-                self.assertEqual(cvar.get(), 'yes{}'.format(j))
+                self.assertEqual(cvar.get(), f'yes{j}')
 
                 for i in range(3):
                     # Test that task passed its context to add_done_callback:
-                    cvar.set('yes{}-{}'.format(i, j))
+                    cvar.set(f'yes{i}-{j}')
                     await asyncio.sleep(0.001)
-                    self.assertEqual(cvar.get(), 'yes{}-{}'.format(i, j))
+                    self.assertEqual(cvar.get(), f'yes{i}-{j}')
 
         task = self.loop.create_task(main())
         self.loop.run_until_complete(task)

tests/test_dns.py

@@ -214,7 +214,7 @@ def test_getaddrinfo_close_loop(self):
         try:
             # Check that we have internet connection
             socket.getaddrinfo('example.com', 80)
-        except socket.error:
+        except OSError:
             raise unittest.SkipTest
 
         async def run():

tests/test_fs_event.py

@@ -86,7 +86,7 @@ async def run(write_task):
 
         with tempfile.TemporaryDirectory() as td_name:
             self.dname = td_name
-            f = open(os.path.join(td_name, self.changed_name), 'wt')
+            f = open(os.path.join(td_name, self.changed_name), 'w')
             f.write('hello!')
             f.close()
             h = self.loop._monitor_fs(td_name, self.event_cb)

tests/test_pipes.py

@@ -74,7 +74,7 @@ def test_read_pipe(self):
         proto = MyReadPipeProto(loop=self.loop)
 
         rpipe, wpipe = os.pipe()
-        pipeobj = io.open(rpipe, 'rb', 1024)
+        pipeobj = open(rpipe, 'rb', 1024)
 
         async def connect():
             t, p = await self.loop.connect_read_pipe(
@@ -106,7 +106,7 @@ def test_read_pty_output(self):
         proto = MyReadPipeProto(loop=self.loop)
 
         master, slave = os.openpty()
-        master_read_obj = io.open(master, 'rb', 0)
+        master_read_obj = open(master, 'rb', 0)
 
         async def connect():
             t, p = await self.loop.connect_read_pipe(
@@ -142,7 +142,7 @@ async def connect():
     def test_write_pipe(self):
         rpipe, wpipe = os.pipe()
         os.set_blocking(rpipe, False)
-        pipeobj = io.open(wpipe, 'wb', 1024)
+        pipeobj = open(wpipe, 'wb', 1024)
 
         proto = MyWritePipeProto(loop=self.loop)
         connect = self.loop.connect_write_pipe(lambda: proto, pipeobj)
@@ -185,7 +185,7 @@ def test_write_pipe_disconnect_on_close(self):
         rsock, wsock = socket.socketpair()
         rsock.setblocking(False)
 
-        pipeobj = io.open(wsock.detach(), 'wb', 1024)
+        pipeobj = open(wsock.detach(), 'wb', 1024)
 
         proto = MyWritePipeProto(loop=self.loop)
         connect = self.loop.connect_write_pipe(lambda: proto, pipeobj)
@@ -207,7 +207,7 @@ def test_write_pty(self):
         master, slave = os.openpty()
         os.set_blocking(master, False)
 
-        slave_write_obj = io.open(slave, 'wb', 0)
+        slave_write_obj = open(slave, 'wb', 0)
 
         proto = MyWritePipeProto(loop=self.loop)
         connect = self.loop.connect_write_pipe(lambda: proto, slave_write_obj)
@@ -250,7 +250,7 @@ def reader(data):
 
     def test_write_buffer_full(self):
         rpipe, wpipe = os.pipe()
-        pipeobj = io.open(wpipe, 'wb', 1024)
+        pipeobj = open(wpipe, 'wb', 1024)
 
         proto = MyWritePipeProto(loop=self.loop)
         connect = self.loop.connect_write_pipe(lambda: proto, pipeobj)

tests/test_process.py

@@ -192,7 +192,7 @@ async def test():
                 stdout=subprocess.PIPE)
 
             pid = proc.pid
-            expected_result = '{}\n'.format(pid).encode()
+            expected_result = f'{pid}\n'.encode()
 
             out, err = await proc.communicate()
             self.assertEqual(out, expected_result)

tests/test_process_spawning.py

@@ -56,7 +56,7 @@ async def spawn_external_process(loop, event):
         BufferType = ctypes.c_char * (BUFFER_LENGTH - 1)
 
         def run_echo(popen, fread, pclose):
-            fd = popen('echo test'.encode('ASCII'), 'r'.encode('ASCII'))
+            fd = popen(b'echo test', b'r')
             try:
                 while True:
                     buffer = BufferType()

tests/test_sourcecode.py

@@ -26,15 +26,14 @@ def test_flake8(self):
                 subprocess.run(
                     [sys.executable, '-m', 'flake8', '--config', config_path],
                     check=True,
-                    stdout=subprocess.PIPE,
-                    stderr=subprocess.PIPE,
+                    capture_output=True,
                     cwd=os.path.join(edgepath, subdir))
             except subprocess.CalledProcessError as ex:
                 output = ex.stdout.decode()
                 output += '\n'
                 output += ex.stderr.decode()
                 raise AssertionError(
-                    'flake8 validation failed: {}\n{}'.format(ex, output)
+                    f'flake8 validation failed: {ex}\n{output}'
                 ) from None
 
     def test_mypy(self):
@@ -59,14 +58,13 @@ def test_mypy(self):
                     'uvloop'
                 ],
                 check=True,
-                stdout=subprocess.PIPE,
-                stderr=subprocess.PIPE,
+                capture_output=True,
                 cwd=edgepath
             )
         except subprocess.CalledProcessError as ex:
             output = ex.stdout.decode()
             output += '\n'
             output += ex.stderr.decode()
             raise AssertionError(
-                'mypy validation failed: {}\n{}'.format(ex, output)
+                f'mypy validation failed: {ex}\n{output}'
             ) from None

tests/test_tcp.py

@@ -2806,7 +2806,7 @@ async def test():
             except AssertionError as e:
                 self.assertEqual(str(e), 'ResourceWarning not triggered')
             else:
-                self.fail('Unexpected ResourceWarning: {}'.format(cm.warning))
+                self.fail(f'Unexpected ResourceWarning: {cm.warning}')
 
     def test_handshake_timeout_handler_leak(self):
         if self.implementation == 'asyncio':

tests/test_unix.py

@@ -166,7 +166,7 @@ async def start_server_sock(start_server):
     def test_create_unix_server_2(self):
         with tempfile.TemporaryDirectory() as td:
             sock_name = os.path.join(td, 'sock')
-            with open(sock_name, 'wt') as f:
+            with open(sock_name, 'w') as f:
                 f.write('x')
 
             with self.assertRaisesRegex(

uvloop/__init__.py

@@ -71,7 +71,7 @@ async def wrapper():
 
             if not __asyncio.iscoroutine(main):
                 raise ValueError(
-                    "a coroutine was expected, got {!r}".format(main)
+                    f"a coroutine was expected, got {main!r}"
                 )
 
             loop = loop_factory()

uvloop/_testbase.py

@@ -141,14 +141,14 @@ def tearDown(self):
                                   handle_name=h_name):
                     self.assertEqual(
                         h_cnt, 0,
-                        'alive {} after test'.format(h_name))
+                        f'alive {h_name} after test')
 
             for h_name, h_cnt in self.loop._debug_handles_total.items():
                 with self.subTest('Total/closed handles',
                                   handle_name=h_name):
                     self.assertEqual(
                         h_cnt, self.loop._debug_handles_closed[h_name],
-                        'total != closed for {}'.format(h_name))
+                        f'total != closed for {h_name}')
 
         asyncio.set_event_loop(None)
         asyncio.set_event_loop_policy(None)
@@ -259,7 +259,7 @@ def find_free_port(start_from=50000):
         with sock:
             try:
                 sock.bind(('', port))
-            except socket.error:
+            except OSError:
                 continue
             else:
                 return port
@@ -386,7 +386,7 @@ def __getattr__(self, name):
         return getattr(self.__sock, name)
 
     def __repr__(self):
-        return '<{} {!r}>'.format(type(self).__name__, self.__sock)
+        return f'<{type(self).__name__} {self.__sock!r}>'
 
 
 class SocketThread(threading.Thread):