Updated a number of comments referring to Python 3.6

docs/source/reference-io.rst

@@ -237,8 +237,7 @@ other constants and functions in the :mod:`ssl` module.
 
 .. warning:: Avoid instantiating :class:`ssl.SSLContext` directly.
    A newly constructed :class:`~ssl.SSLContext` has less secure
-   defaults than one returned by :func:`ssl.create_default_context`,
-   dramatically so before Python 3.6.
+   defaults than one returned by :func:`ssl.create_default_context`.
 
 Instead of using :meth:`ssl.SSLContext.wrap_socket`, you
 create a :class:`SSLStream`:
@@ -722,7 +721,7 @@ subprocess`` in order to access constants such as ``PIPE`` or
 
 Currently, Trio always uses unbuffered byte streams for communicating
 with a process, so it does not support the ``encoding``, ``errors``,
-``universal_newlines`` (alias ``text`` in 3.7+), and ``bufsize``
+``universal_newlines`` (alias ``text``), and ``bufsize``
 options.
 
 

setup.py

@@ -44,7 +44,7 @@
 Vital statistics:
 
 * Supported environments: Linux, macOS, or Windows running some kind of Python
-  3.6-or-better (either CPython or PyPy3 is fine). \\*BSD and illumos likely
+  3.7-or-better (either CPython or PyPy3 is fine). \\*BSD and illumos likely
   work too, but are not tested.
 
 * Install: ``python3 -m pip install -U trio`` (or on Windows, maybe

trio/_core/_entry_queue.py

@@ -15,8 +15,8 @@ class EntryQueue:
     # not signal-safe. deque is implemented in C, so each operation is atomic
     # WRT threads (and this is guaranteed in the docs), AND each operation is
     # atomic WRT signal delivery (signal handlers can run on either side, but
-    # not *during* a deque operation). dict makes similar guarantees - and on
-    # CPython 3.6 and PyPy, it's even ordered!
+    # not *during* a deque operation). dict makes similar guarantees - and
+    # it's even ordered!
     queue = attr.ib(factory=deque)
     idempotent_queue = attr.ib(factory=dict)
 

trio/_core/_run.py

@@ -2137,7 +2137,7 @@ def unrolled_run(runner, async_fn, args, host_uses_signal_set_wakeup_fd=False):
                 try:
                     # We used to unwrap the Outcome object here and send/throw
                     # its contents in directly, but it turns out that .throw()
-                    # is buggy, at least on CPython 3.6:
+                    # is buggy, at least before CPython 3.9:
                     #   https://bugs.python.org/issue29587
                     #   https://bugs.python.org/issue29590
                     # So now we send in the Outcome object and unwrap it on the

trio/_core/tests/test_multierror.py

@@ -162,8 +162,6 @@ def test_traceback_recursion():
     # This could trigger an infinite recursion; the 'seen' set is supposed to prevent
     # this.
     exc1.__cause__ = MultiError([exc1, exc2, exc3])
-    # python traceback.TracebackException < 3.6.4 does not support unhashable exceptions
-    # and raises a TypeError exception
     format_exception(*einfo(exc1))
 
 

trio/_core/tests/test_run.py

@@ -1056,7 +1056,7 @@ async def child2():
     ]
 
 
-# At least as of CPython 3.6, using .throw() to raise an exception inside a
+# Before CPython 3.9, using .throw() to raise an exception inside a
 # coroutine/generator causes the original exc_info state to be lost, so things
 # like re-raising and exception chaining are broken.
 #

trio/_highlevel_ssl_helpers.py

@@ -19,7 +19,6 @@ async def open_ssl_over_tcp_stream(
     *,
     https_compatible=False,
     ssl_context=None,
-    # No trailing comma b/c bpo-9232 (fixed in py36)
     happy_eyeballs_delay=DEFAULT_DELAY,
 ):
     """Make a TLS-encrypted Connection to the given host and port over TCP.

trio/_socket.py

@@ -50,7 +50,7 @@ async def __aexit__(self, etype, value, tb):
 try:
     from socket import IPPROTO_IPV6
 except ImportError:
-    # As of at least 3.6, python on Windows is missing IPPROTO_IPV6
+    # Before Python 3.8, Windows is missing IPPROTO_IPV6
     # https://bugs.python.org/issue29515
     if sys.platform == "win32":  # pragma: no branch
         IPPROTO_IPV6 = 41

trio/_util.py

@@ -270,13 +270,12 @@ def __getitem__(self, _):
 
 
 # If a new class inherits from any ABC, then the new class's metaclass has to
-# inherit from ABCMeta. If a new class inherits from typing.Generic, and
-# you're using Python 3.6, then the new class's metaclass has to
-# inherit from typing.GenericMeta. Some of the classes that want to use Final
-# or NoPublicConstructor inherit from ABCs and generics, so Final has to
-# inherit from these metaclasses. Fortunately, GenericMeta inherits from
-# ABCMeta, so inheriting from GenericMeta alone is sufficient (when it
-# exists at all).
+# inherit from ABCMeta. If a new class inherits from typing.Generic, then the
+# new class's metaclass has to inherit from typing.GenericMeta. Some of the
+# classes that want to use Final or NoPublicConstructor inherit from ABCs and
+# generics, so Final has to inherit from these metaclasses. Fortunately,
+# GenericMeta inherits from ABCMeta, so inheriting from GenericMeta alone is
+# sufficient (when it exists at all).
 if not t.TYPE_CHECKING and hasattr(t, "GenericMeta"):
     BaseMeta = t.GenericMeta
 else:

trio/tests/test_threads.py

@@ -300,8 +300,8 @@ async def test_run_in_worker_thread_limiter(MAX, cancel, use_default_limiter):
     try:
         # We used to use regular variables and 'nonlocal' here, but it turns
         # out that it's not safe to assign to closed-over variables that are
-        # visible in multiple threads, at least as of CPython 3.6 and PyPy
-        # 5.8:
+        # visible in multiple threads, at least as of CPython 3.10 and PyPy
+        # 7.3:
         #
         #   https://bugs.python.org/issue30744
         #   https://bitbucket.org/pypy/pypy/issues/2591/