Feature: switch from select.select to selectors

Use `DefaultSelector` as automatically selected most efficient.
Use context manager for not holding resources.

urwid/event_loop/select_loop.py

@@ -25,7 +25,7 @@
 
 import contextlib
 import heapq
-import select
+import selectors
 import time
 import typing
 from contextlib import suppress
@@ -43,7 +43,7 @@
 
 class SelectEventLoop(EventLoop):
     """
-    Event loop based on :func:`select.select`
+    Event loop based on :func:`selectors.DefaultSelector.select`
     """
 
     def __init__(self) -> None:
@@ -159,28 +159,29 @@ def _loop(self) -> None:
         fds = list(self._watch_files)
         tm: float | Literal["idle"] | None = None
 
-        if self._alarms or self._did_something:
-            timeout = 0.0
+        with selectors.DefaultSelector() as selector:
+            for fd in fds:
+                selector.register(fd, selectors.EVENT_READ)
 
-            if self._alarms:
-                timeout_ = self._alarms[0][0]
-                tm = timeout_
-                timeout = max(timeout, timeout_ - time.time())
-
-            if self._did_something and (not self._alarms or (self._alarms and timeout > 0)):
+            if self._alarms or self._did_something:
                 timeout = 0.0
-                tm = "idle"
 
-            if fds:
-                ready, _w, _err = select.select(fds, [], fds, timeout)
+                if self._alarms:
+                    timeout_ = self._alarms[0][0]
+                    tm = timeout_
+                    timeout = max(timeout, timeout_ - time.time())
+
+                if self._did_something and (not self._alarms or (self._alarms and timeout > 0)):
+                    timeout = 0.0
+                    tm = "idle"
+
+                ready = [event.fd for event, _ in selector.select(timeout)]
+
+            elif fds:
+                ready = [event.fd for event, _ in selector.select()]
             else:
                 ready = []
 
-        elif fds:
-            ready, _w, _err = select.select(fds, [], fds)
-        else:
-            ready = []
-
         if not ready:
             if tm == "idle":
                 self._entering_idle()

urwid/vterm.py

@@ -27,7 +27,7 @@
 import fcntl
 import os
 import pty
-import select
+import selectors
 import signal
 import struct
 import sys
@@ -1689,13 +1689,14 @@ def remove_watch(self) -> None:
         self.main_loop.remove_watch_file(self.master)
 
     def wait_and_feed(self, timeout: float = 1.0) -> None:
-        while True:
-            try:
-                select.select([self.master], [], [], timeout)
-                break
-            except OSError as e:
-                if e.args[0] != 4:
-                    raise
+        with selectors.DefaultSelector() as selector:
+            selector.register(self.master, selectors.EVENT_READ)
+            while True:
+                try:
+                    selector.select(timeout)
+                    break
+                except InterruptedError:
+                    pass  # Allow interrupt
         self.feed()
 
     def feed(self) -> None:

urwid/web_display.py

@@ -27,7 +27,7 @@
 import glob
 import os
 import random
-import select
+import selectors
 import signal
 import socket
 import string
@@ -904,16 +904,16 @@ def get_input(self, raw_keys: bool = False) -> list[str] | tuple[list[str], list
         """Return pending input as a list."""
         pending_input = []
         resized = False
+        with selectors.DefaultSelector() as selector:
+            selector.register(self.input_fd, selectors.EVENT_READ)
 
-        try:
-            iready, _oready, _eready = select.select([self.input_fd], [], [], 0.5)
-        except OSError as e:
-            # return on interruptions
-            if e.args[0] == 4:
+            try:
+                iready = [event.fd for event, _ in selector.select(0.5)]
+            except InterruptedError:
+                # return on interruptions
                 if raw_keys:
                     return [], []
                 return []
-            raise
 
         if not iready:
             if raw_keys: