From 702670e7e3f6c5f5f02f7557c291ced4e3cb236d Mon Sep 17 00:00:00 2001
From: Tom Milligan <tom@reinfer.io>
Date: Fri, 17 Jul 2020 13:17:43 +0100
Subject: [PATCH 01/33] server: reproduce select() out of range error

---
 cheroot/test/test_server.py | 46 +++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index 2108e2bb9a..be6a8ecb29 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -236,3 +236,49 @@ def test_peercreds_unix_sock_with_lookup(peercreds_enabled_server):
         peercreds_text_resp = requests.get(unix_base_uri + PEERCRED_TEXTS_URI)
         peercreds_text_resp.raise_for_status()
         assert peercreds_text_resp.text == expected_textcreds
+
+
+def test_high_number_of_file_descriptors():
+    """Test the server does not crash with a high file-descriptor value.
+
+    This test should cause a server crash, as the server will try to
+    select() a file-descriptor higher than 1024.
+    """
+    increased_nofile_limit = 2048
+    sockets = []
+    try:
+        import resource
+        import socket
+
+        # We have to increase the nofile limit above 1024
+        # Otherwise we see a 'Too many files open' error, instead of
+        # an error due to the file descriptor number being too high
+        (soft_limit, hard_limit) = resource.getrlimit(resource.RLIMIT_NOFILE)
+        resource.setrlimit(
+            resource.RLIMIT_NOFILE,
+            (increased_nofile_limit, increased_nofile_limit),
+        )
+
+        # Hold a bunch of open file descriptors, so the next ones the server
+        # opens are higher than 1024
+        for i in range(1024):
+            new_socket = socket.socket()
+            sockets.append(new_socket)
+
+        # Create our server
+        httpserver = HTTPServer(
+            bind_addr=(ANY_INTERFACE_IPV4, EPHEMERAL_PORT), gateway=Gateway,
+        )
+        httpserver.prepare()
+        # This will trigger a crash if select() is used in the implementation
+        httpserver.tick()
+
+    finally:
+        # Stop our server, and close our open resources
+        httpserver.stop()
+        for socket in sockets:
+            socket.close()
+
+        # Reset the limit back to the soft limit
+        # (setting the hard_limit is an error)
+        resource.setrlimit(resource.RLIMIT_NOFILE, (soft_limit, soft_limit))

From 3e9ac1fb19c4afcf5574ad5188b02aa10487e193 Mon Sep 17 00:00:00 2001
From: Tom Milligan <tom@reinfer.io>
Date: Fri, 17 Jul 2020 14:45:10 +0100
Subject: [PATCH 02/33] feedback: move imports, make finally robust

---
 cheroot/test/test_server.py | 33 ++++++++++++++++++---------------
 1 file changed, 18 insertions(+), 15 deletions(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index be6a8ecb29..59182f317d 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -6,6 +6,7 @@
 __metaclass__ = type
 
 import os
+import resource
 import socket
 import tempfile
 import threading
@@ -244,40 +245,42 @@ def test_high_number_of_file_descriptors():
     This test should cause a server crash, as the server will try to
     select() a file-descriptor higher than 1024.
     """
+    # Get current resource limits to restore them later
+    (soft_limit, hard_limit) = resource.getrlimit(resource.RLIMIT_NOFILE)
     increased_nofile_limit = 2048
-    sockets = []
-    try:
-        import resource
-        import socket
 
+    # Create our server
+    httpserver = HTTPServer(
+        bind_addr=(ANY_INTERFACE_IPV4, EPHEMERAL_PORT), gateway=Gateway,
+    )
+    # Hoard a lot of file descriptors by opening and storing a lot of sockets
+    test_sockets = []
+
+    try:
         # We have to increase the nofile limit above 1024
         # Otherwise we see a 'Too many files open' error, instead of
         # an error due to the file descriptor number being too high
-        (soft_limit, hard_limit) = resource.getrlimit(resource.RLIMIT_NOFILE)
         resource.setrlimit(
             resource.RLIMIT_NOFILE,
             (increased_nofile_limit, increased_nofile_limit),
         )
 
-        # Hold a bunch of open file descriptors, so the next ones the server
+        # Open a lot of file descriptors, so the next ones the server
         # opens are higher than 1024
         for i in range(1024):
-            new_socket = socket.socket()
-            sockets.append(new_socket)
+            test_sockets.append(socket.socket())
 
-        # Create our server
-        httpserver = HTTPServer(
-            bind_addr=(ANY_INTERFACE_IPV4, EPHEMERAL_PORT), gateway=Gateway,
-        )
         httpserver.prepare()
         # This will trigger a crash if select() is used in the implementation
         httpserver.tick()
 
     finally:
-        # Stop our server, and close our open resources
+        # Close our open resources
+        for test_socket in test_sockets:
+            test_socket.close()
+
+        # Stop our server
         httpserver.stop()
-        for socket in sockets:
-            socket.close()
 
         # Reset the limit back to the soft limit
         # (setting the hard_limit is an error)

From 0edbd0facf333d2c1ef16ce0cfca22a62c2e1c66 Mon Sep 17 00:00:00 2001
From: Tom Milligan <tom@reinfer.io>
Date: Fri, 17 Jul 2020 14:48:24 +0100
Subject: [PATCH 03/33] feedback: don't change hard_limit when adjusting nofile
 resource

---
 cheroot/test/test_server.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index 59182f317d..a083e77e20 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -262,7 +262,7 @@ def test_high_number_of_file_descriptors():
         # an error due to the file descriptor number being too high
         resource.setrlimit(
             resource.RLIMIT_NOFILE,
-            (increased_nofile_limit, increased_nofile_limit),
+            (increased_nofile_limit, hard_limit),
         )
 
         # Open a lot of file descriptors, so the next ones the server
@@ -284,4 +284,4 @@ def test_high_number_of_file_descriptors():
 
         # Reset the limit back to the soft limit
         # (setting the hard_limit is an error)
-        resource.setrlimit(resource.RLIMIT_NOFILE, (soft_limit, soft_limit))
+        resource.setrlimit(resource.RLIMIT_NOFILE, (soft_limit, hard_limit))

From bcae452bd920e8c08b6368d9a63c5dc24f541e26 Mon Sep 17 00:00:00 2001
From: Tom Milligan <tom@reinfer.io>
Date: Fri, 17 Jul 2020 14:54:57 +0100
Subject: [PATCH 04/33] feedback: add assertions to enforce we reach a
 file-descriptor over 1024

---
 cheroot/test/test_server.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index a083e77e20..dbbc9448a4 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -269,10 +269,13 @@ def test_high_number_of_file_descriptors():
         # opens are higher than 1024
         for i in range(1024):
             test_sockets.append(socket.socket())
+        assert test_sockets[-1].fileno() >= 1024
 
         httpserver.prepare()
         # This will trigger a crash if select() is used in the implementation
         httpserver.tick()
+        with socket.socket() as sock:
+            assert sock.fileno() >= 1024
 
     finally:
         # Close our open resources

From 53e8a5f0517c73adb0bd9948706564cc2d50ab88 Mon Sep 17 00:00:00 2001
From: Tom Milligan <tom@reinfer.io>
Date: Fri, 17 Jul 2020 16:17:33 +0100
Subject: [PATCH 05/33] make test_high_number_of_file_descriptors py27
 compatible

---
 cheroot/test/test_server.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index dbbc9448a4..8c19d59b68 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -274,8 +274,12 @@ def test_high_number_of_file_descriptors():
         httpserver.prepare()
         # This will trigger a crash if select() is used in the implementation
         httpserver.tick()
-        with socket.socket() as sock:
+
+        sock = socket.socket()
+        try:
             assert sock.fileno() >= 1024
+        finally:
+            sock.close()
 
     finally:
         # Close our open resources

From 0fad95066414ee40f002112d3b96cedb5a62e4f7 Mon Sep 17 00:00:00 2001
From: Tom Milligan <tom@reinfer.io>
Date: Fri, 17 Jul 2020 16:22:34 +0100
Subject: [PATCH 06/33] connections: replace select with selectors/selectors2

---
 cheroot/connections.py | 45 +++++++++++++++++++++++++++++-------------
 setup.cfg              |  1 +
 2 files changed, 32 insertions(+), 14 deletions(-)

diff --git a/cheroot/connections.py b/cheroot/connections.py
index 28bc973b61..55cce50e1d 100644
--- a/cheroot/connections.py
+++ b/cheroot/connections.py
@@ -5,7 +5,10 @@
 
 import io
 import os
-import select
+try:
+    import selectors
+except ImportError:
+    import selectors2 as selectors
 import socket
 import time
 
@@ -62,6 +65,7 @@ def __init__(self, server):
         """
         self.server = server
         self.connections = []
+        self._selector = selectors.DefaultSelector()
 
     def put(self, conn):
         """Put idle connection into the ConnectionManager to be managed.
@@ -133,10 +137,9 @@ def get_conn(self, server_socket):
         ss_fileno = server_socket.fileno()
         socket_dict[ss_fileno] = server_socket
         try:
-            rlist, _, _ = select.select(list(socket_dict), [], [], 0.1)
-            # No available socket.
-            if not rlist:
-                return None
+            for sock in socket_dict:
+                self._selector.register(sock, selectors.EVENT_READ)
+            key_events = self._selector.select(timeout=0.1)
         except OSError:
             # Mark any connection which no longer appears valid.
             for fno, conn in list(socket_dict.items()):
@@ -155,15 +158,29 @@ def get_conn(self, server_socket):
 
             # Wait for the next tick to occur.
             return None
-
-        try:
-            # See if we have a new connection coming in.
-            rlist.remove(ss_fileno)
-        except ValueError:
-            # No new connection, but reuse existing socket.
-            conn = socket_dict[rlist.pop()]
-        else:
-            conn = server_socket
+        finally:
+            for sock in socket_dict:
+                self._selector.unregister(sock)
+
+        # See if we have a new connection coming in.
+        new_connection = False
+        rlist = []
+        for key, event in key_events:
+            if key.fd == ss_fileno:
+                # If we have a new connection, reuse the server socket
+                new_connection = True
+                conn = server_socket
+            else:
+                # Make a list of all the other sockets ready to read
+                rlist.append(key.fd)
+
+        if new_connection is False:
+            if len(rlist) == 0:
+                # If we didn't get any readable sockets, wait for the next tick
+                return None
+            else:
+                # No new connection, but reuse existing socket.
+                conn = socket_dict[rlist.pop()]
 
         # All remaining connections in rlist should be marked as ready.
         for fno in rlist:
diff --git a/setup.cfg b/setup.cfg
index 1c0b9425b8..93bf839bf6 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -65,6 +65,7 @@ setup_requires =
 # These are required in actual runtime:
 install_requires =
     backports.functools_lru_cache; python_version < '3.3'
+    selectors2; python_version< '3.4'
     six>=1.11.0
     more_itertools>=2.6
     jaraco.functools

From 919d5637626f695518980766acadac2ae13619db Mon Sep 17 00:00:00 2001
From: Tom Milligan <tom@reinfer.io>
Date: Fri, 17 Jul 2020 16:52:16 +0100
Subject: [PATCH 07/33] only run test_high_number_of_file_descriptors on unix

---
 cheroot/test/test_server.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index 8c19d59b68..d481b45080 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -239,6 +239,7 @@ def test_peercreds_unix_sock_with_lookup(peercreds_enabled_server):
         assert peercreds_text_resp.text == expected_textcreds
 
 
+@unix_only_sock_test
 def test_high_number_of_file_descriptors():
     """Test the server does not crash with a high file-descriptor value.
 

From 7047f0b1ebc5320295d193a418c6f42e82d051a3 Mon Sep 17 00:00:00 2001
From: Tom Milligan <tom@reinfer.io>
Date: Fri, 17 Jul 2020 17:10:35 +0100
Subject: [PATCH 08/33] really only run test_high_number_of_file_descriptors on
 unix

---
 cheroot/test/test_server.py | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index d481b45080..215be7db55 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -6,7 +6,6 @@
 __metaclass__ = type
 
 import os
-import resource
 import socket
 import tempfile
 import threading
@@ -20,7 +19,7 @@
 from six.moves import urllib
 
 from .._compat import bton, ntob
-from .._compat import IS_LINUX, IS_MACOS, SYS_PLATFORM
+from .._compat import IS_LINUX, IS_MACOS, IS_WINDOWS, SYS_PLATFORM
 from ..server import IS_UID_GID_RESOLVABLE, Gateway, HTTPServer
 from ..testing import (
     ANY_INTERFACE_IPV4,
@@ -239,13 +238,22 @@ def test_peercreds_unix_sock_with_lookup(peercreds_enabled_server):
         assert peercreds_text_resp.text == expected_textcreds
 
 
-@unix_only_sock_test
+@pytest.mark.skipif(
+    IS_WINDOWS,
+    reason=(
+        'This regression test is for a Linux bug, and the resource module '
+        'is not available on Windows.'
+    ),
+)
 def test_high_number_of_file_descriptors():
     """Test the server does not crash with a high file-descriptor value.
 
     This test should cause a server crash, as the server will try to
     select() a file-descriptor higher than 1024.
     """
+    # Imported here, as it is not available on Windows
+    import resource
+
     # Get current resource limits to restore them later
     (soft_limit, hard_limit) = resource.getrlimit(resource.RLIMIT_NOFILE)
     increased_nofile_limit = 2048

From 6ca52e06c907636396bdef6b80f92deef77543cc Mon Sep 17 00:00:00 2001
From: Tom Milligan <tom@reinfer.io>
Date: Fri, 17 Jul 2020 17:42:57 +0100
Subject: [PATCH 09/33] feedback: use closing contextmanager for socket

---
 cheroot/test/test_server.py | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index 215be7db55..dce7b2b879 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -5,6 +5,7 @@
 from __future__ import absolute_import, division, print_function
 __metaclass__ = type
 
+from contextlib import closing
 import os
 import socket
 import tempfile
@@ -284,11 +285,8 @@ def test_high_number_of_file_descriptors():
         # This will trigger a crash if select() is used in the implementation
         httpserver.tick()
 
-        sock = socket.socket()
-        try:
+        with closing(socket.socket()) as sock:
             assert sock.fileno() >= 1024
-        finally:
-            sock.close()
 
     finally:
         # Close our open resources

From 85b800d55b56cbfe19e54f52c009222fe2d79e4b Mon Sep 17 00:00:00 2001
From: Tom Milligan <tommilligan@users.noreply.github.com>
Date: Sun, 19 Jul 2020 15:05:40 +0100
Subject: [PATCH 10/33] Update cheroot/test/test_server.py

Co-authored-by: Sviatoslav Sydorenko <wk.cvs.github@sydorenko.org.ua>
---
 cheroot/test/test_server.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index dce7b2b879..92ff91f9bc 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -285,7 +285,7 @@ def test_high_number_of_file_descriptors():
         # This will trigger a crash if select() is used in the implementation
         httpserver.tick()
 
-        with closing(socket.socket()) as sock:
+        with closing(socket.socket()) as sock:  # closing is here for py2-compat
             assert sock.fileno() >= 1024
 
     finally:

From e69b2606b7d642273cfd932f3e260a8d45deb6c8 Mon Sep 17 00:00:00 2001
From: Tom Milligan <tommilligan@users.noreply.github.com>
Date: Sun, 19 Jul 2020 15:06:00 +0100
Subject: [PATCH 11/33] Update cheroot/connections.py

Co-authored-by: Sviatoslav Sydorenko <wk.cvs.github@sydorenko.org.ua>
---
 cheroot/connections.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cheroot/connections.py b/cheroot/connections.py
index 55cce50e1d..d755f574d0 100644
--- a/cheroot/connections.py
+++ b/cheroot/connections.py
@@ -174,7 +174,7 @@ def get_conn(self, server_socket):
                 # Make a list of all the other sockets ready to read
                 rlist.append(key.fd)
 
-        if new_connection is False:
+        if not new_connection:
             if len(rlist) == 0:
                 # If we didn't get any readable sockets, wait for the next tick
                 return None

From d273ae968635ba9cdd699aaabe6ee09cc6a785f1 Mon Sep 17 00:00:00 2001
From: Tom Milligan <tommilligan@users.noreply.github.com>
Date: Sun, 19 Jul 2020 15:06:11 +0100
Subject: [PATCH 12/33] Update cheroot/connections.py

Co-authored-by: Sviatoslav Sydorenko <wk.cvs.github@sydorenko.org.ua>
---
 cheroot/connections.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/cheroot/connections.py b/cheroot/connections.py
index d755f574d0..3e3d10d773 100644
--- a/cheroot/connections.py
+++ b/cheroot/connections.py
@@ -178,9 +178,9 @@ def get_conn(self, server_socket):
             if len(rlist) == 0:
                 # If we didn't get any readable sockets, wait for the next tick
                 return None
-            else:
-                # No new connection, but reuse existing socket.
-                conn = socket_dict[rlist.pop()]
+
+            # No new connection, but reuse the existing socket.
+            conn = socket_dict[rlist.pop()]
 
         # All remaining connections in rlist should be marked as ready.
         for fno in rlist:

From b66420398247d8c25308ecb66fc52b023ee6de9f Mon Sep 17 00:00:00 2001
From: Tom Milligan <tommilligan@users.noreply.github.com>
Date: Sun, 19 Jul 2020 15:06:32 +0100
Subject: [PATCH 13/33] Update cheroot/test/test_server.py

Co-authored-by: Sviatoslav Sydorenko <wk.cvs.github@sydorenko.org.ua>
---
 cheroot/test/test_server.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index 92ff91f9bc..83994e0022 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -246,7 +246,8 @@ def test_peercreds_unix_sock_with_lookup(peercreds_enabled_server):
         'is not available on Windows.'
     ),
 )
-def test_high_number_of_file_descriptors():
+@pytest.mark.forked
+def test_high_number_of_file_descriptors(http_server):
     """Test the server does not crash with a high file-descriptor value.
 
     This test should cause a server crash, as the server will try to

From c4aec4fbb709df9256e2d899b57ef47ca79f5d1f Mon Sep 17 00:00:00 2001
From: Tom Milligan <tommilligan@users.noreply.github.com>
Date: Sun, 19 Jul 2020 15:06:42 +0100
Subject: [PATCH 14/33] Update cheroot/test/test_server.py

Co-authored-by: Sviatoslav Sydorenko <wk.cvs.github@sydorenko.org.ua>
---
 cheroot/test/test_server.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index 83994e0022..e43b1b7a19 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -243,7 +243,7 @@ def test_peercreds_unix_sock_with_lookup(peercreds_enabled_server):
     IS_WINDOWS,
     reason=(
         'This regression test is for a Linux bug, and the resource module '
-        'is not available on Windows.'
+        'is not available on Windows'
     ),
 )
 @pytest.mark.forked

From 153e6660539ec0ccc626a566fbfae03ea80dabe5 Mon Sep 17 00:00:00 2001
From: Tom Milligan <tommilligan@users.noreply.github.com>
Date: Sun, 19 Jul 2020 15:07:10 +0100
Subject: [PATCH 15/33] Update cheroot/test/test_server.py

Co-authored-by: Sviatoslav Sydorenko <wk.cvs.github@sydorenko.org.ua>
---
 cheroot/test/test_server.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index e43b1b7a19..25ef849e23 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -261,9 +261,7 @@ def test_high_number_of_file_descriptors(http_server):
     increased_nofile_limit = 2048
 
     # Create our server
-    httpserver = HTTPServer(
-        bind_addr=(ANY_INTERFACE_IPV4, EPHEMERAL_PORT), gateway=Gateway,
-    )
+    httpserver = http_server.send((ANY_INTERFACE_IPV4, EPHEMERAL_PORT))
     # Hoard a lot of file descriptors by opening and storing a lot of sockets
     test_sockets = []
 

From 513ed2612b76ced39b3cd979ef9fd0c75f51e340 Mon Sep 17 00:00:00 2001
From: Tom Milligan <tommilligan@users.noreply.github.com>
Date: Sun, 19 Jul 2020 17:38:40 +0100
Subject: [PATCH 16/33] Update cheroot/test/test_server.py

Co-authored-by: Sviatoslav Sydorenko <wk.cvs.github@sydorenko.org.ua>
---
 cheroot/test/test_server.py | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index 25ef849e23..55bf6b1230 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -253,8 +253,10 @@ def test_high_number_of_file_descriptors(http_server):
     This test should cause a server crash, as the server will try to
     select() a file-descriptor higher than 1024.
     """
-    # Imported here, as it is not available on Windows
-    import resource
+    resource = pytest.importorskip(
+        'resource',
+        reason='The "resource" module is Unix-specific',
+    )
 
     # Get current resource limits to restore them later
     (soft_limit, hard_limit) = resource.getrlimit(resource.RLIMIT_NOFILE)

From ff26fdfccc244596f766bae095511d7ce58cf7ab Mon Sep 17 00:00:00 2001
From: Tom Milligan <tommilligan@users.noreply.github.com>
Date: Sun, 19 Jul 2020 17:40:13 +0100
Subject: [PATCH 17/33] Apply suggestions from code review

Co-authored-by: Sviatoslav Sydorenko <wk.cvs.github@sydorenko.org.ua>
---
 cheroot/connections.py | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/cheroot/connections.py b/cheroot/connections.py
index 3e3d10d773..6cc2088544 100644
--- a/cheroot/connections.py
+++ b/cheroot/connections.py
@@ -139,7 +139,7 @@ def get_conn(self, server_socket):
         try:
             for sock in socket_dict:
                 self._selector.register(sock, selectors.EVENT_READ)
-            key_events = self._selector.select(timeout=0.1)
+            key_events = [key.fd for key, _event self._selector.select(timeout=0.1)]
         except OSError:
             # Mark any connection which no longer appears valid.
             for fno, conn in list(socket_dict.items()):
@@ -163,19 +163,20 @@ def get_conn(self, server_socket):
                 self._selector.unregister(sock)
 
         # See if we have a new connection coming in.
-        new_connection = False
-        rlist = []
-        for key, event in key_events:
-            if key.fd == ss_fileno:
-                # If we have a new connection, reuse the server socket
+        try:
+            key_events.pop(ss_fileno)
+        except KeyError:
+                new_connection = False
+        else:
                 new_connection = True
+                # If we have a new connection, reuse the server socket
                 conn = server_socket
-            else:
-                # Make a list of all the other sockets ready to read
-                rlist.append(key.fd)
+
+        # Make a list of all the other sockets ready to read
+        rlist = list(key_events.keys())
 
         if not new_connection:
-            if len(rlist) == 0:
+            if not rlist:
                 # If we didn't get any readable sockets, wait for the next tick
                 return None
 

From ee7261b6f8d1a4cf1fbbde10f311b061626d6da9 Mon Sep 17 00:00:00 2001
From: Tom Milligan <tom@reinfer.io>
Date: Sun, 19 Jul 2020 17:47:37 +0100
Subject: [PATCH 18/33] move selectors import to compat

---
 cheroot/_compat.py     | 6 ++++++
 cheroot/connections.py | 5 +----
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/cheroot/_compat.py b/cheroot/_compat.py
index 63df078119..bc89db8161 100644
--- a/cheroot/_compat.py
+++ b/cheroot/_compat.py
@@ -8,6 +8,12 @@
 
 import six
 
+# Not used in this file, imported elsewhere as 'from ._compat import selectors'
+try:
+    import selectors
+except ImportError:
+    import selectors2 as selectors  # noqa: F401
+
 try:
     import ssl
     IS_ABOVE_OPENSSL10 = ssl.OPENSSL_VERSION_INFO >= (1, 1)
diff --git a/cheroot/connections.py b/cheroot/connections.py
index 6cc2088544..0425599491 100644
--- a/cheroot/connections.py
+++ b/cheroot/connections.py
@@ -5,14 +5,11 @@
 
 import io
 import os
-try:
-    import selectors
-except ImportError:
-    import selectors2 as selectors
 import socket
 import time
 
 from . import errors
+from ._compat import selectors
 from .makefile import MakeFile
 
 import six

From 5fbbb9ef002aa6435db2af9784cacaf9811f35d7 Mon Sep 17 00:00:00 2001
From: Tom Milligan <tom@reinfer.io>
Date: Sun, 19 Jul 2020 18:55:58 +0100
Subject: [PATCH 19/33] integrate feedback with tests, make work again

---
 cheroot/connections.py      | 36 ++++++++++++++++--------------------
 cheroot/test/test_server.py | 37 ++++++++++++++++++++++++-------------
 setup.cfg                   |  1 +
 3 files changed, 41 insertions(+), 33 deletions(-)

diff --git a/cheroot/connections.py b/cheroot/connections.py
index 0425599491..57438386e9 100644
--- a/cheroot/connections.py
+++ b/cheroot/connections.py
@@ -134,9 +134,12 @@ def get_conn(self, server_socket):
         ss_fileno = server_socket.fileno()
         socket_dict[ss_fileno] = server_socket
         try:
-            for sock in socket_dict:
-                self._selector.register(sock, selectors.EVENT_READ)
-            key_events = [key.fd for key, _event self._selector.select(timeout=0.1)]
+            for fno in socket_dict:
+                self._selector.register(fno, selectors.EVENT_READ)
+            rlist = [
+                key.fd for key, _event
+                in self._selector.select(timeout=0.1)
+            ]
         except OSError:
             # Mark any connection which no longer appears valid.
             for fno, conn in list(socket_dict.items()):
@@ -156,29 +159,22 @@ def get_conn(self, server_socket):
             # Wait for the next tick to occur.
             return None
         finally:
-            for sock in socket_dict:
-                self._selector.unregister(sock)
+            for fno in socket_dict:
+                self._selector.unregister(fno)
 
-        # See if we have a new connection coming in.
         try:
-            key_events.pop(ss_fileno)
-        except KeyError:
-                new_connection = False
-        else:
-                new_connection = True
-                # If we have a new connection, reuse the server socket
-                conn = server_socket
-
-        # Make a list of all the other sockets ready to read
-        rlist = list(key_events.keys())
-
-        if not new_connection:
+            # See if we have a new connection coming in.
+            rlist.remove(ss_fileno)
+        except ValueError:
+            # If we didn't get any readable sockets, wait for the next tick
             if not rlist:
-                # If we didn't get any readable sockets, wait for the next tick
                 return None
 
-            # No new connection, but reuse the existing socket.
+            # No new connection, but reuse an existing socket.
             conn = socket_dict[rlist.pop()]
+        else:
+            # If we have a new connection, reuse the server socket
+            conn = server_socket
 
         # All remaining connections in rlist should be marked as ready.
         for fno in rlist:
diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index 55bf6b1230..a2f855c9d4 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -258,12 +258,18 @@ def test_high_number_of_file_descriptors(http_server):
         reason='The "resource" module is Unix-specific',
     )
 
+    # We want to force the server to use a file-descriptor with a number above
+    # this value
+    high_fd_no = 1024
+
     # Get current resource limits to restore them later
     (soft_limit, hard_limit) = resource.getrlimit(resource.RLIMIT_NOFILE)
-    increased_nofile_limit = 2048
 
     # Create our server
-    httpserver = http_server.send((ANY_INTERFACE_IPV4, EPHEMERAL_PORT))
+    httpserver = HTTPServer(
+        bind_addr=(ANY_INTERFACE_IPV4, EPHEMERAL_PORT), gateway=Gateway,
+    )
+    httpserver.prepare()
     # Hoard a lot of file descriptors by opening and storing a lot of sockets
     test_sockets = []
 
@@ -273,21 +279,27 @@ def test_high_number_of_file_descriptors(http_server):
         # an error due to the file descriptor number being too high
         resource.setrlimit(
             resource.RLIMIT_NOFILE,
-            (increased_nofile_limit, hard_limit),
+            (high_fd_no * 2, hard_limit),
         )
 
-        # Open a lot of file descriptors, so the next ones the server
-        # opens are higher than 1024
-        for i in range(1024):
-            test_sockets.append(socket.socket())
-        assert test_sockets[-1].fileno() >= 1024
+        # Open a lot of file descriptors, so the next one the server opens is
+        # a hight number
+        for i in range(high_fd_no):
+            sock = socket.socket()
+            test_sockets.append(sock)
+            # If we reach a high enough number, we don't need to open more
+            if sock.fileno() >= high_fd_no:
+                break
+        # Check we opened enough descriptors to reach a high number
+        assert test_sockets[-1].fileno() >= high_fd_no
 
-        httpserver.prepare()
         # This will trigger a crash if select() is used in the implementation
         httpserver.tick()
 
-        with closing(socket.socket()) as sock:  # closing is here for py2-compat
-            assert sock.fileno() >= 1024
+        # We use closing here for py2-compat
+        with closing(socket.socket()) as sock:
+            # Check new sockets created are still above our target number
+            assert sock.fileno() >= high_fd_no
 
     finally:
         # Close our open resources
@@ -297,6 +309,5 @@ def test_high_number_of_file_descriptors(http_server):
         # Stop our server
         httpserver.stop()
 
-        # Reset the limit back to the soft limit
-        # (setting the hard_limit is an error)
+        # Reset the resource limit back to the original soft limit
         resource.setrlimit(resource.RLIMIT_NOFILE, (soft_limit, hard_limit))
diff --git a/setup.cfg b/setup.cfg
index 93bf839bf6..7d89eb99f7 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -86,6 +86,7 @@ docs =
 
 testing =
     pytest>=4.6.6
+    pytest-forked>=1.2.0
     pytest-mock>=1.11.0
     pytest-sugar>=0.9.3
     pytest-testmon<1.0.0

From bdc33cbd8e76406d4f3ff238a61576bf576ad016 Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk.cvs.github@sydorenko.org.ua>
Date: Mon, 20 Jul 2020 00:57:42 +0200
Subject: [PATCH 20/33] Use `http_server` fixture in
 `test_high_number_of_file_descriptors`

---
 cheroot/test/test_server.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index a2f855c9d4..af70abfcf0 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -266,9 +266,7 @@ def test_high_number_of_file_descriptors(http_server):
     (soft_limit, hard_limit) = resource.getrlimit(resource.RLIMIT_NOFILE)
 
     # Create our server
-    httpserver = HTTPServer(
-        bind_addr=(ANY_INTERFACE_IPV4, EPHEMERAL_PORT), gateway=Gateway,
-    )
+    httpserver = http_server.send((ANY_INTERFACE_IPV4, EPHEMERAL_PORT))
     httpserver.prepare()
     # Hoard a lot of file descriptors by opening and storing a lot of sockets
     test_sockets = []

From aea6bf943a5a813a3c4a5ed3e1cb6670cdbffe32 Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk.cvs.github@sydorenko.org.ua>
Date: Mon, 20 Jul 2020 00:58:50 +0200
Subject: [PATCH 21/33] Improve `test_high_number_of_file_descriptors`
 docstring

---
 cheroot/test/test_server.py | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index af70abfcf0..1bb816c815 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -250,8 +250,11 @@ def test_peercreds_unix_sock_with_lookup(peercreds_enabled_server):
 def test_high_number_of_file_descriptors(http_server):
     """Test the server does not crash with a high file-descriptor value.
 
-    This test should cause a server crash, as the server will try to
-    select() a file-descriptor higher than 1024.
+    This test shouldn't cause a server crash when trying to access
+    file-descriptor higher than 1024.
+
+    The earlier implementation used to rely on `select()` syscall that
+    doesn't support file descriptors with numbers higher than 1024.
     """
     resource = pytest.importorskip(
         'resource',

From 84f86162f76fd18f116822e56fd55fee38cd7bb6 Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk.cvs.github@sydorenko.org.ua>
Date: Mon, 20 Jul 2020 00:59:18 +0200
Subject: [PATCH 22/33] Add LGTM ignore comments to `_compat`

---
 cheroot/_compat.py | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/cheroot/_compat.py b/cheroot/_compat.py
index bc89db8161..7f7a380a1a 100644
--- a/cheroot/_compat.py
+++ b/cheroot/_compat.py
@@ -8,11 +8,10 @@
 
 import six
 
-# Not used in this file, imported elsewhere as 'from ._compat import selectors'
 try:
-    import selectors
+    import selectors  # lgtm [py/unused-import]
 except ImportError:
-    import selectors2 as selectors  # noqa: F401
+    import selectors2 as selectors  # noqa: F401  # lgtm [py/unused-import]
 
 try:
     import ssl

From 38a4ec37cc1bf0438dcedc11d9c5dd69d0c0a565 Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk@sydorenko.org.ua>
Date: Mon, 20 Jul 2020 01:23:20 +0200
Subject: [PATCH 23/33] Revert "Use `http_server` fixture in
 `test_high_number_of_file_descriptors`"

This reverts commit 7e0900c88f16fa4bab4baf85825ac3331cf911b9.
---
 cheroot/test/test_server.py | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index 1bb816c815..ccba1f9996 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -247,7 +247,7 @@ def test_peercreds_unix_sock_with_lookup(peercreds_enabled_server):
     ),
 )
 @pytest.mark.forked
-def test_high_number_of_file_descriptors(http_server):
+def test_high_number_of_file_descriptors():
     """Test the server does not crash with a high file-descriptor value.
 
     This test shouldn't cause a server crash when trying to access
@@ -269,7 +269,9 @@ def test_high_number_of_file_descriptors(http_server):
     (soft_limit, hard_limit) = resource.getrlimit(resource.RLIMIT_NOFILE)
 
     # Create our server
-    httpserver = http_server.send((ANY_INTERFACE_IPV4, EPHEMERAL_PORT))
+    httpserver = HTTPServer(
+        bind_addr=(ANY_INTERFACE_IPV4, EPHEMERAL_PORT), gateway=Gateway,
+    )
     httpserver.prepare()
     # Hoard a lot of file descriptors by opening and storing a lot of sockets
     test_sockets = []

From ef5d44dd4fca140d2de01036e8a2eb251e2ed2df Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk@sydorenko.org.ua>
Date: Mon, 20 Jul 2020 02:04:14 +0200
Subject: [PATCH 24/33] Move high fd num test prerequisites to fixtures

---
 cheroot/test/test_server.py | 109 +++++++++++++++++++++---------------
 1 file changed, 65 insertions(+), 44 deletions(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index ccba1f9996..491bf7dc7c 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -241,13 +241,20 @@ def test_peercreds_unix_sock_with_lookup(peercreds_enabled_server):
 
 @pytest.mark.skipif(
     IS_WINDOWS,
-    reason=(
-        'This regression test is for a Linux bug, and the resource module '
-        'is not available on Windows'
-    ),
+    reason='This regression test is for a Linux bug, '
+    'and the resource module is not available on Windows',
 )
 @pytest.mark.forked
-def test_high_number_of_file_descriptors():
+@pytest.mark.parametrize(
+    'resource_limit',
+    (
+        1024,
+        2048,
+    ),
+    indirect=('resource_limit', ),
+)
+@pytest.mark.usefixtures('many_open_sockets')
+def test_high_number_of_file_descriptors(resource_limit):
     """Test the server does not crash with a high file-descriptor value.
 
     This test shouldn't cause a server crash when trying to access
@@ -256,61 +263,75 @@ def test_high_number_of_file_descriptors():
     The earlier implementation used to rely on `select()` syscall that
     doesn't support file descriptors with numbers higher than 1024.
     """
-    resource = pytest.importorskip(
-        'resource',
-        reason='The "resource" module is Unix-specific',
-    )
-
-    # We want to force the server to use a file-descriptor with a number above
-    # this value
-    high_fd_no = 1024
-
-    # Get current resource limits to restore them later
-    (soft_limit, hard_limit) = resource.getrlimit(resource.RLIMIT_NOFILE)
+    # We want to force the server to use a file-descriptor with
+    # a number above resource_limit
 
     # Create our server
     httpserver = HTTPServer(
         bind_addr=(ANY_INTERFACE_IPV4, EPHEMERAL_PORT), gateway=Gateway,
     )
     httpserver.prepare()
-    # Hoard a lot of file descriptors by opening and storing a lot of sockets
-    test_sockets = []
 
     try:
-        # We have to increase the nofile limit above 1024
-        # Otherwise we see a 'Too many files open' error, instead of
-        # an error due to the file descriptor number being too high
-        resource.setrlimit(
-            resource.RLIMIT_NOFILE,
-            (high_fd_no * 2, hard_limit),
-        )
-
-        # Open a lot of file descriptors, so the next one the server opens is
-        # a hight number
-        for i in range(high_fd_no):
-            sock = socket.socket()
-            test_sockets.append(sock)
-            # If we reach a high enough number, we don't need to open more
-            if sock.fileno() >= high_fd_no:
-                break
-        # Check we opened enough descriptors to reach a high number
-        assert test_sockets[-1].fileno() >= high_fd_no
-
         # This will trigger a crash if select() is used in the implementation
         httpserver.tick()
-
+    except:  # noqa: E722
+        raise  # only needed for `else` to work
+    else:
         # We use closing here for py2-compat
         with closing(socket.socket()) as sock:
             # Check new sockets created are still above our target number
-            assert sock.fileno() >= high_fd_no
-
+            assert sock.fileno() >= resource_limit
     finally:
-        # Close our open resources
-        for test_socket in test_sockets:
-            test_socket.close()
-
         # Stop our server
         httpserver.stop()
 
+
+@pytest.fixture
+def resource_limit(request):
+    """Set the resource limit two times bigger then requested."""
+    resource = pytest.importorskip(
+        'resource',
+        reason='The "resource" module is Unix-specific',
+    )
+
+    # Get current resource limits to restore them later
+    soft_limit, hard_limit = resource.getrlimit(resource.RLIMIT_NOFILE)
+
+    # We have to increase the nofile limit above 1024
+    # Otherwise we see a 'Too many files open' error, instead of
+    # an error due to the file descriptor number being too high
+    resource.setrlimit(
+        resource.RLIMIT_NOFILE,
+        (request.param * 2, hard_limit),
+    )
+
+    try:  # noqa: WPS501
+        yield request.param
+    finally:
         # Reset the resource limit back to the original soft limit
         resource.setrlimit(resource.RLIMIT_NOFILE, (soft_limit, hard_limit))
+
+
+@pytest.fixture
+def many_open_sockets(resource_limit):
+    """Allocate a lot of file descriptors by opening dummy sockets."""
+    # Hoard a lot of file descriptors by opening and storing a lot of sockets
+    test_sockets = []
+    # Open a lot of file descriptors, so the next one the server
+    # opens is a high number
+    try:
+        for i in range(resource_limit):
+            sock = socket.socket()
+            test_sockets.append(sock)
+            # If we reach a high enough number, we don't need to open more
+            if sock.fileno() >= resource_limit:
+                break
+        # Check we opened enough descriptors to reach a high number
+        the_highest_fileno = test_sockets[-1].fileno()
+        assert the_highest_fileno >= resource_limit
+        yield the_highest_fileno
+    finally:
+        # Close our open resources
+        for test_socket in test_sockets:
+            test_socket.close()

From 5617f5379a481b85dc633b04422ea462134e621d Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk@sydorenko.org.ua>
Date: Mon, 20 Jul 2020 02:15:30 +0200
Subject: [PATCH 25/33] Fix marking `select()` as code in docstring

---
 cheroot/test/test_server.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index 491bf7dc7c..bc4b68ef8e 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -260,7 +260,7 @@ def test_high_number_of_file_descriptors(resource_limit):
     This test shouldn't cause a server crash when trying to access
     file-descriptor higher than 1024.
 
-    The earlier implementation used to rely on `select()` syscall that
+    The earlier implementation used to rely on ``select()`` syscall that
     doesn't support file descriptors with numbers higher than 1024.
     """
     # We want to force the server to use a file-descriptor with

From 24f5d13eb036bf0a7ffe6c079ac0693fa8b549f8 Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk@sydorenko.org.ua>
Date: Mon, 20 Jul 2020 02:26:56 +0200
Subject: [PATCH 26/33] Add "syscall" to the list of known words

---
 docs/spelling_wordlist.txt | 1 +
 1 file changed, 1 insertion(+)

diff --git a/docs/spelling_wordlist.txt b/docs/spelling_wordlist.txt
index bfd2eb8713..9b872b9f3f 100644
--- a/docs/spelling_wordlist.txt
+++ b/docs/spelling_wordlist.txt
@@ -45,6 +45,7 @@ ssl
 stdout
 subclasses
 submodules
+syscall
 systemd
 threadpool
 Tidelift

From d0c56f25f1fe9b8facf57e129d4b3d72116ca658 Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk@sydorenko.org.ua>
Date: Mon, 20 Jul 2020 17:04:38 +0200
Subject: [PATCH 27/33] Only install pytest-forked where it's supported

---
 setup.cfg | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/setup.cfg b/setup.cfg
index 7d89eb99f7..cf2df16f9a 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -86,7 +86,8 @@ docs =
 
 testing =
     pytest>=4.6.6
-    pytest-forked>=1.2.0
+    pytest-forked>=1.1.3; sys_platform != "win32" and python_version >= '3.0' and python_version <= '3.4'
+    pytest-forked>=1.2.0; sys_platform != "win32" and (python_version < '3.0' or python_version > '3.4')
     pytest-mock>=1.11.0
     pytest-sugar>=0.9.3
     pytest-testmon<1.0.0

From ba258dd752255563097d3a73f902009b1ce324dc Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk@sydorenko.org.ua>
Date: Mon, 20 Jul 2020 18:59:31 +0200
Subject: [PATCH 28/33] Apply updated add-trailing-comma edits

---
 cheroot/test/test_server.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index bc4b68ef8e..9ac6ae2050 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -251,7 +251,7 @@ def test_peercreds_unix_sock_with_lookup(peercreds_enabled_server):
         1024,
         2048,
     ),
-    indirect=('resource_limit', ),
+    indirect=('resource_limit',),
 )
 @pytest.mark.usefixtures('many_open_sockets')
 def test_high_number_of_file_descriptors(resource_limit):

From c8dea9bf5b7b727efb521332929c75586509ce71 Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk@sydorenko.org.ua>
Date: Mon, 20 Jul 2020 23:05:48 +0200
Subject: [PATCH 29/33] Conditionally decorate test with forked mark

---
 cheroot/test/test_server.py | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/cheroot/test/test_server.py b/cheroot/test/test_server.py
index 9ac6ae2050..7b0ef9137b 100644
--- a/cheroot/test/test_server.py
+++ b/cheroot/test/test_server.py
@@ -244,7 +244,6 @@ def test_peercreds_unix_sock_with_lookup(peercreds_enabled_server):
     reason='This regression test is for a Linux bug, '
     'and the resource module is not available on Windows',
 )
-@pytest.mark.forked
 @pytest.mark.parametrize(
     'resource_limit',
     (
@@ -287,6 +286,12 @@ def test_high_number_of_file_descriptors(resource_limit):
         httpserver.stop()
 
 
+if not IS_WINDOWS:
+    test_high_number_of_file_descriptors = pytest.mark.forked(
+        test_high_number_of_file_descriptors,
+    )
+
+
 @pytest.fixture
 def resource_limit(request):
     """Set the resource limit two times bigger then requested."""

From 72252db0c4162d2186cc23940557b81bee78220d Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk@sydorenko.org.ua>
Date: Tue, 21 Jul 2020 21:25:47 +0200
Subject: [PATCH 30/33] Bump setup-python GHA to v2.1.1

---
 .github/workflows/python-tests.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/python-tests.yml b/.github/workflows/python-tests.yml
index b5e24fb418..858d9b8269 100644
--- a/.github/workflows/python-tests.yml
+++ b/.github/workflows/python-tests.yml
@@ -32,7 +32,7 @@ jobs:
     steps:
     - uses: actions/checkout@master
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v2
+      uses: actions/setup-python@v2.1.1
       with:
         python-version: ${{ matrix.python-version }}
     - name: Pip cache

From e996f20e29838ff1f95b597ee459d48c98ea2f22 Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk@sydorenko.org.ua>
Date: Tue, 21 Jul 2020 23:59:25 +0200
Subject: [PATCH 31/33] Add selectors34 fallback for py27 under 64-bit Win

This change addresses a bug in selectors2 (that is resolved in master
but is unreleased) with fd of the "long" type not being recognized as
"int". Here's the traceback it causes:

  Traceback (most recent call last):
    File "C:\projects\cheroot\cheroot\server.py", line 1788, in serve
      self.tick()
    File "C:\projects\cheroot\cheroot\server.py", line 2023, in tick
      conn = self.connections.get_conn(self.socket)
    File "C:\projects\cheroot\cheroot\connections.py", line 163, in get_conn
      self._selector.unregister(fno)
    File "c:\projects\cheroot\.tox\python\lib\site-packages\selectors2.py", line 249, in unregister
      key = super(SelectSelector, self).unregister(fileobj)
    File "c:\projects\cheroot\.tox\python\lib\site-packages\selectors2.py", line 155, in unregister
      key = self._fd_to_key.pop(self._fileobj_lookup(fileobj))
    File "c:\projects\cheroot\.tox\python\lib\site-packages\selectors2.py", line 127, in _fileobj_lookup
      return _fileobj_to_fd(fileobj)
    File "c:\projects\cheroot\.tox\python\lib\site-packages\selectors2.py", line 90, in _fileobj_to_fd
      raise ValueError("Invalid file object: {0!r}".format(fileobj))
  ValueError: Invalid file object: 916L

Refs:
  * https://github.com/sethmlarson/selectors2/pull/10
  * https://twitter.com/webKnjaZ/status/1285695028136992769
  * https://github.com/berkerpeksag/selectors34/blob/1.2.0/selectors34.py#L51
  * https://github.com/cherrypy/cheroot/pull/301#issuecomment-662127125
---
 cheroot/_compat.py | 6 +++++-
 setup.cfg          | 3 ++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/cheroot/_compat.py b/cheroot/_compat.py
index 7f7a380a1a..f879e5eee6 100644
--- a/cheroot/_compat.py
+++ b/cheroot/_compat.py
@@ -1,3 +1,4 @@
+# pylint: disable=unused-import
 """Compatibility code for using Cheroot with various versions of Python."""
 
 from __future__ import absolute_import, division, print_function
@@ -11,7 +12,10 @@
 try:
     import selectors  # lgtm [py/unused-import]
 except ImportError:
-    import selectors2 as selectors  # noqa: F401  # lgtm [py/unused-import]
+    try:
+        import selectors2 as selectors  # noqa: F401  # lgtm [py/unused-import]
+    except ImportError:
+        import selectors34 as selectors  # noqa: F401 # lgtm [py/unused-import]
 
 try:
     import ssl
diff --git a/setup.cfg b/setup.cfg
index cf2df16f9a..e56717d9e1 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -65,7 +65,8 @@ setup_requires =
 # These are required in actual runtime:
 install_requires =
     backports.functools_lru_cache; python_version < '3.3'
-    selectors2; python_version< '3.4'
+    selectors2; python_version < '3.4' and (sys_platform != "win32" or (sys_platform == "win32" and python_version >= '3.0'))
+    selectors34; python_version < '3.0' and sys_platform == "win32"
     six>=1.11.0
     more_itertools>=2.6
     jaraco.functools

From dc2c17d00ae9f23bd3940ba6fcd98cb8ab4530de Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk@sydorenko.org.ua>
Date: Wed, 22 Jul 2020 00:56:11 +0200
Subject: [PATCH 32/33] Revert "Add selectors34 fallback for py27 under 64-bit
 Win"

This reverts commit e996f20e29838ff1f95b597ee459d48c98ea2f22.

Thanks to @sethmlarson who published `selectors==2.0.2` on PyPI
we no longer need a fallback to `selectors34`.

Ref: https://twitter.com/sethmlarson/status/1285706586514751489
---
 cheroot/_compat.py | 5 +----
 setup.cfg          | 3 +--
 2 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/cheroot/_compat.py b/cheroot/_compat.py
index f879e5eee6..3ebbf2a81d 100644
--- a/cheroot/_compat.py
+++ b/cheroot/_compat.py
@@ -12,10 +12,7 @@
 try:
     import selectors  # lgtm [py/unused-import]
 except ImportError:
-    try:
-        import selectors2 as selectors  # noqa: F401  # lgtm [py/unused-import]
-    except ImportError:
-        import selectors34 as selectors  # noqa: F401 # lgtm [py/unused-import]
+    import selectors2 as selectors  # noqa: F401  # lgtm [py/unused-import]
 
 try:
     import ssl
diff --git a/setup.cfg b/setup.cfg
index e56717d9e1..cf2df16f9a 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -65,8 +65,7 @@ setup_requires =
 # These are required in actual runtime:
 install_requires =
     backports.functools_lru_cache; python_version < '3.3'
-    selectors2; python_version < '3.4' and (sys_platform != "win32" or (sys_platform == "win32" and python_version >= '3.0'))
-    selectors34; python_version < '3.0' and sys_platform == "win32"
+    selectors2; python_version< '3.4'
     six>=1.11.0
     more_itertools>=2.6
     jaraco.functools

From f15243f7a146032617f2e2e476fda364bdb3b676 Mon Sep 17 00:00:00 2001
From: Sviatoslav Sydorenko <wk@sydorenko.org.ua>
Date: Wed, 22 Jul 2020 01:16:32 +0200
Subject: [PATCH 33/33] Revert "Bump setup-python GHA to v2.1.1"

This reverts commit 72252db0c4162d2186cc23940557b81bee78220d.
---
 .github/workflows/python-tests.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/python-tests.yml b/.github/workflows/python-tests.yml
index 858d9b8269..b5e24fb418 100644
--- a/.github/workflows/python-tests.yml
+++ b/.github/workflows/python-tests.yml
@@ -32,7 +32,7 @@ jobs:
     steps:
     - uses: actions/checkout@master
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v2.1.1
+      uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
     - name: Pip cache