also run it on the notes-to-self directory

notes-to-self/how-does-windows-so-reuseaddr-work.py

@@ -10,6 +10,7 @@
 modes = ["default", "SO_REUSEADDR", "SO_EXCLUSIVEADDRUSE"]
 bind_types = ["wildcard", "specific"]
 
+
 def sock(mode):
     s = socket.socket(family=socket.AF_INET)
     if mode == "SO_REUSEADDR":
@@ -18,6 +19,7 @@ def sock(mode):
         s.setsockopt(socket.SOL_SOCKET, socket.SO_EXCLUSIVEADDRUSE, 1)
     return s
 
+
 def bind(sock, bind_type):
     if bind_type == "wildcard":
         sock.bind(("0.0.0.0", 12345))
@@ -26,6 +28,7 @@ def bind(sock, bind_type):
     else:
         assert False
 
+
 def table_entry(mode1, bind_type1, mode2, bind_type2):
     with sock(mode1) as sock1:
         bind(sock1, bind_type1)
@@ -41,19 +44,22 @@ def table_entry(mode1, bind_type1, mode2, bind_type2):
         else:
             return "Success"
 
-print("""
+
+print(
+    """
                                                        second bind
                                | """
-+ " | ".join(["%-19s" % mode for mode in modes])
+    + " | ".join(["%-19s" % mode for mode in modes])
 )
 
-print("""                              """, end='')
+print("""                              """, end="")
 for mode in modes:
-    print(" | " + " | ".join(["%8s" % bind_type for bind_type in bind_types]), end='')
+    print(" | " + " | ".join(["%8s" % bind_type for bind_type in bind_types]), end="")
 
-print("""
+print(
+    """
 first bind                     -----------------------------------------------------------------"""
-#            default | wildcard |    INUSE |  Success |   ACCESS |  Success |    INUSE |  Success
+    #            default | wildcard |    INUSE |  Success |   ACCESS |  Success |    INUSE |  Success
 )
 
 for i, mode1 in enumerate(modes):
@@ -63,6 +69,8 @@ def table_entry(mode1, bind_type1, mode2, bind_type2):
             for l, bind_type2 in enumerate(bind_types):
                 entry = table_entry(mode1, bind_type1, mode2, bind_type2)
                 row.append(entry)
-                #print(mode1, bind_type1, mode2, bind_type2, entry)
-        print("{:>19} | {:>8} | ".format(mode1, bind_type1)
-              + " | ".join(["%8s" % entry for entry in row]))
+                # print(mode1, bind_type1, mode2, bind_type2, entry)
+        print(
+            f"{mode1:>19} | {bind_type1:>8} | "
+            + " | ".join(["%8s" % entry for entry in row])
+        )

notes-to-self/reopen-pipe.py

@@ -3,12 +3,13 @@
 import time
 import tempfile
 
+
 def check_reopen(r1, w):
     try:
         print("Reopening read end")
-        r2 = os.open("/proc/self/fd/{}".format(r1), os.O_RDONLY)
+        r2 = os.open(f"/proc/self/fd/{r1}", os.O_RDONLY)
 
-        print("r1 is {}, r2 is {}".format(r1, r2))
+        print(f"r1 is {r1}, r2 is {r2}")
 
         print("checking they both can receive from w...")
 
@@ -36,11 +37,12 @@ def check_reopen(r1, w):
         def sleep_then_write():
             time.sleep(1)
             os.write(w, b"c")
+
         threading.Thread(target=sleep_then_write, daemon=True).start()
         assert os.read(r1, 1) == b"c"
         print("r1 definitely seems to be in blocking mode")
     except Exception as exc:
-        print("ERROR: {!r}".format(exc))
+        print(f"ERROR: {exc!r}")
 
 
 print("-- testing anonymous pipe --")
@@ -63,6 +65,6 @@ def sleep_then_write():
 
 print("-- testing socketpair --")
 import socket
+
 rs, ws = socket.socketpair()
 check_reopen(rs.fileno(), ws.fileno())
-

notes-to-self/schedule-timing.py

@@ -4,16 +4,18 @@
 LOOPS = 0
 RUNNING = True
 
+
 async def reschedule_loop(depth):
     if depth == 0:
         global LOOPS
         while RUNNING:
             LOOPS += 1
             await trio.sleep(0)
-            #await trio.lowlevel.cancel_shielded_checkpoint()
+            # await trio.lowlevel.cancel_shielded_checkpoint()
     else:
         await reschedule_loop(depth - 1)
 
+
 async def report_loop():
     global RUNNING
     try:
@@ -25,13 +27,15 @@ async def report_loop():
             end_count = LOOPS
             loops = end_count - start_count
             duration = end_time - start_time
-            print("{} loops/sec".format(loops / duration))
+            print(f"{loops / duration} loops/sec")
     finally:
         RUNNING = False
 
+
 async def main():
     async with trio.open_nursery() as nursery:
         nursery.start_soon(reschedule_loop, 10)
         nursery.start_soon(report_loop)
 
+
 trio.run(main)

notes-to-self/socketpair-buffering.py

@@ -32,6 +32,6 @@
     except BlockingIOError:
         pass
 
-    print("setsockopt bufsize {}: {}".format(bufsize, i))
+    print(f"setsockopt bufsize {bufsize}: {i}")
     a.close()
     b.close()

notes-to-self/ssl-handshake/ssl-handshake.py

@@ -8,6 +8,7 @@
 server_ctx = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH)
 server_ctx.load_cert_chain("trio-test-1.pem")
 
+
 def _ssl_echo_serve_sync(sock):
     try:
         wrapped = server_ctx.wrap_socket(sock, server_side=True)
@@ -20,16 +21,19 @@ def _ssl_echo_serve_sync(sock):
     except BrokenPipeError:
         pass
 
+
 @contextmanager
 def echo_server_connection():
     client_sock, server_sock = socket.socketpair()
     with client_sock, server_sock:
         t = threading.Thread(
-            target=_ssl_echo_serve_sync, args=(server_sock,), daemon=True)
+            target=_ssl_echo_serve_sync, args=(server_sock,), daemon=True
+        )
         t.start()
 
         yield client_sock
 
+
 class ManuallyWrappedSocket:
     def __init__(self, ctx, sock, **kwargs):
         self.incoming = ssl.MemoryBIO()
@@ -82,21 +86,23 @@ def unwrap(self):
 def wrap_socket_via_wrap_socket(ctx, sock, **kwargs):
     return ctx.wrap_socket(sock, do_handshake_on_connect=False, **kwargs)
 
+
 def wrap_socket_via_wrap_bio(ctx, sock, **kwargs):
     return ManuallyWrappedSocket(ctx, sock, **kwargs)
 
 
 for wrap_socket in [
-        wrap_socket_via_wrap_socket,
-        wrap_socket_via_wrap_bio,
+    wrap_socket_via_wrap_socket,
+    wrap_socket_via_wrap_bio,
 ]:
-    print("\n--- checking {} ---\n".format(wrap_socket.__name__))
+    print(f"\n--- checking {wrap_socket.__name__} ---\n")
 
     print("checking with do_handshake + correct hostname...")
     with echo_server_connection() as client_sock:
         client_ctx = ssl.create_default_context(cafile="trio-test-CA.pem")
         wrapped = wrap_socket(
-            client_ctx, client_sock, server_hostname="trio-test-1.example.org")
+            client_ctx, client_sock, server_hostname="trio-test-1.example.org"
+        )
         wrapped.do_handshake()
         wrapped.sendall(b"x")
         assert wrapped.recv(1) == b"x"
@@ -107,7 +113,8 @@ def wrap_socket_via_wrap_bio(ctx, sock, **kwargs):
     with echo_server_connection() as client_sock:
         client_ctx = ssl.create_default_context(cafile="trio-test-CA.pem")
         wrapped = wrap_socket(
-            client_ctx, client_sock, server_hostname="trio-test-2.example.org")
+            client_ctx, client_sock, server_hostname="trio-test-2.example.org"
+        )
         try:
             wrapped.do_handshake()
         except Exception:
@@ -119,7 +126,8 @@ def wrap_socket_via_wrap_bio(ctx, sock, **kwargs):
     with echo_server_connection() as client_sock:
         client_ctx = ssl.create_default_context(cafile="trio-test-CA.pem")
         wrapped = wrap_socket(
-            client_ctx, client_sock, server_hostname="trio-test-2.example.org")
+            client_ctx, client_sock, server_hostname="trio-test-2.example.org"
+        )
         # We forgot to call do_handshake
         # But the hostname is wrong so something had better error out...
         sent = b"x"

notes-to-self/sslobject.py

@@ -15,14 +15,16 @@
 soutb = ssl.MemoryBIO()
 sso = server_ctx.wrap_bio(sinb, soutb, server_side=True)
 
+
 @contextmanager
 def expect(etype):
     try:
         yield
     except etype:
         pass
     else:
-        raise AssertionError("expected {}".format(etype))
+        raise AssertionError(f"expected {etype}")
+
 
 with expect(ssl.SSLWantReadError):
     cso.do_handshake()

notes-to-self/thread-closure-bug-demo.py

@@ -8,18 +8,21 @@
 
 COUNT = 100
 
+
 def slow_tracefunc(frame, event, arg):
     # A no-op trace function that sleeps briefly to make us more likely to hit
     # the race condition.
     time.sleep(0.01)
     return slow_tracefunc
 
+
 def run_with_slow_tracefunc(fn):
     # settrace() only takes effect when you enter a new frame, so we need this
     # little dance:
     sys.settrace(slow_tracefunc)
     return fn()
 
+
 def outer():
     x = 0
     # We hide the done variable inside a list, because we want to use it to
@@ -46,13 +49,14 @@ def traced_looper():
     t.start()
 
     for i in range(COUNT):
-        print("after {} increments, x is {}".format(i, x))
+        print(f"after {i} increments, x is {x}")
         x += 1
         time.sleep(0.01)
 
     done[0] = True
     t.join()
 
-    print("Final discrepancy: {} (should be 0)".format(COUNT - x))
+    print(f"Final discrepancy: {COUNT - x} (should be 0)")
+
 
 outer()

notes-to-self/thread-dispatch-bench.py

@@ -10,11 +10,13 @@
 
 COUNT = 10000
 
+
 def worker(in_q, out_q):
     while True:
         job = in_q.get()
         out_q.put(job())
 
+
 def main():
     in_q = Queue()
     out_q = Queue()
@@ -28,6 +30,7 @@ def main():
             in_q.put(lambda: None)
             out_q.get()
         end = time.monotonic()
-        print("{:.2f} µs/job".format((end - start) / COUNT * 1e6))
+        print(f"{(end - start) / COUNT * 1e6:.2f} µs/job")
+
 
 main()

notes-to-self/time-wait-windows-exclusiveaddruse.py

@@ -8,15 +8,17 @@
 import socket
 from contextlib import contextmanager
 
+
 @contextmanager
 def report_outcome(tagline):
     try:
         yield
     except OSError as exc:
-        print("{}: failed".format(tagline))
-        print("    details: {!r}".format(exc))
+        print(f"{tagline}: failed")
+        print(f"    details: {exc!r}")
     else:
-        print("{}: succeeded".format(tagline))
+        print(f"{tagline}: succeeded")
+
 
 # Set up initial listening socket
 lsock = socket.socket()

notes-to-self/time-wait.py

@@ -31,6 +31,7 @@
 
 import attr
 
+
 @attr.s(repr=False)
 class Options:
     listen1_early = attr.ib(default=None)
@@ -49,9 +50,10 @@ def describe(self):
         for f in attr.fields(self.__class__):
             value = getattr(self, f.name)
             if value is not None:
-                info.append("{}={}".format(f.name, value))
+                info.append(f"{f.name}={value}")
         return "Set/unset: {}".format(", ".join(info))
 
+
 def time_wait(options):
     print(options.describe())
 
@@ -60,7 +62,7 @@ def time_wait(options):
     listen0 = socket.socket()
     listen0.bind(("127.0.0.1", 0))
     sockaddr = listen0.getsockname()
-    #print("  ", sockaddr)
+    # print("  ", sockaddr)
     listen0.close()
 
     listen1 = socket.socket()
@@ -98,6 +100,7 @@ def time_wait(options):
     else:
         print("  -> ok")
 
+
 time_wait(Options())
 time_wait(Options(listen1_early=True, server=True, listen2=True))
 time_wait(Options(listen1_early=True))