Deadlock fix

CHANGELOG.md

@@ -5,12 +5,16 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
-## Unreleased
+## [0.68.0] - 2024-06-13
 
 ### Added
 
 - Added `ContentSwitcher.add_content`
 
+### Fixed
+
+- Improved handling of non-tty input https://github.com/Textualize/textual/pull/4647
+
 ## [0.67.1] - 2024-06-12
 
 ### Changed
@@ -2128,6 +2132,7 @@ https://textual.textualize.io/blog/2022/11/08/version-040/#version-040
 - New handler system for messages that doesn't require inheritance
 - Improved traceback handling
 
+[0.68.0]: https://github.com/Textualize/textual/compare/v0.67.1...v0.68.0
 [0.67.1]: https://github.com/Textualize/textual/compare/v0.67.0...v0.67.1
 [0.67.0]: https://github.com/Textualize/textual/compare/v0.66.0...v0.67.0
 [0.66.0]: https://github.com/Textualize/textual/compare/v0.65.2...v0.66.0

examples/dictionary.py

@@ -46,6 +46,7 @@ async def lookup_word(self, word: str) -> None:
                 results = response.json()
             except Exception:
                 self.query_one("#results", Markdown).update(response.text)
+                return
 
         if word == self.query_one(Input).value:
             markdown = self.make_word_markdown(results)

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "textual"
-version = "0.67.1"
+version = "0.68.0"
 homepage = "https://github.com/Textualize/textual"
 repository = "https://github.com/Textualize/textual"
 documentation = "https://textual.textualize.io/"

src/textual/app.py

@@ -2564,6 +2564,7 @@ async def invoke_ready_callback() -> None:
                         console = Console()
                         console.print(self.screen._compositor)
                         console.print()
+
                     driver.stop_application_mode()
         except Exception as error:
             self._handle_exception(error)
@@ -2616,9 +2617,14 @@ async def recompose(self) -> None:
 
         Recomposing will remove children and call `self.compose` again to remount.
         """
-        async with self.screen.batch():
-            await self.screen.query("*").exclude(".-textual-system").remove()
-            await self.screen.mount_all(compose(self))
+        if self._exit:
+            return
+        try:
+            async with self.screen.batch():
+                await self.screen.query("*").exclude(".-textual-system").remove()
+                await self.screen.mount_all(compose(self))
+        except ScreenStackError:
+            pass
 
     def _register_child(
         self, parent: DOMNode, child: Widget, before: int | None, after: int | None
@@ -3409,14 +3415,15 @@ async def _prune_node(self, root: Widget) -> None:
                     child._close_messages(wait=True) for child in close_children
                 ]
                 try:
+                    # Close all the children
                     await asyncio.wait_for(
                         asyncio.gather(*close_messages), self.CLOSE_TIMEOUT
                     )
                 except asyncio.TimeoutError:
                     # Likely a deadlock if we get here
                     # If not a deadlock, increase CLOSE_TIMEOUT, or set it to None
                     raise asyncio.TimeoutError(
-                        f"Timeout waiting for {close_children!r} to close; possible deadlock\n"
+                        f"Timeout waiting for {close_children!r} to close; possible deadlock (consider changing App.CLOSE_TIMEOUT)\n"
                     ) from None
                 finally:
                     for child in children:

src/textual/driver.py

@@ -99,7 +99,6 @@ def process_event(self, event: events.Event) -> None:
                 and not event.button
                 and self._last_move_event is not None
             ):
-
                 # Deduplicate self._down_buttons while preserving order.
                 buttons = list(dict.fromkeys(self._down_buttons).keys())
                 self._down_buttons.clear()

src/textual/drivers/linux_driver.py

@@ -14,6 +14,7 @@
 import rich.repr
 
 from .. import events
+from .._parser import ParseError
 from .._xterm_parser import XTermParser
 from ..driver import Driver
 from ..geometry import Size
@@ -46,6 +47,7 @@ def __init__(
         super().__init__(app, debug=debug, mouse=mouse, size=size)
         self._file = sys.__stderr__
         self.fileno = sys.__stdin__.fileno()
+        self.input_tty = sys.__stdin__.isatty()
         self.attrs_before: list[Any] | None = None
         self.exit_event = Event()
         self._key_thread: Thread | None = None
@@ -235,7 +237,10 @@ def on_terminal_resize(signum, stack) -> None:
             # defaults to ASCII EOT = Ctrl-D = 4.)
             newattr[tty.CC][termios.VMIN] = 1
 
-            termios.tcsetattr(self.fileno, termios.TCSANOW, newattr)
+            try:
+                termios.tcsetattr(self.fileno, termios.TCSANOW, newattr)
+            except termios.error:
+                pass
 
         self.write("\x1b[?25l")  # Hide cursor
         self.write("\x1b[?1004h")  # Enable FocusIn/FocusOut.
@@ -264,6 +269,8 @@ def _request_terminal_sync_mode_support(self) -> None:
         # Terminals should ignore this sequence if not supported.
         # Apple terminal doesn't, and writes a single 'p' in to the terminal,
         # so we will make a special case for Apple terminal (which doesn't support sync anyway).
+        if not self.input_tty:
+            return
         if os.environ.get("TERM_PROGRAM", "") != "Apple_Terminal":
             self.write("\033[?2026$p")
             self.flush()
@@ -309,8 +316,11 @@ def disable_input(self) -> None:
                 if self._key_thread is not None:
                     self._key_thread.join()
                 self.exit_event.clear()
-                termios.tcflush(self.fileno, termios.TCIFLUSH)
-        except Exception as error:
+                try:
+                    termios.tcflush(self.fileno, termios.TCIFLUSH)
+                except termios.error:
+                    pass
+        except Exception:
             # TODO: log this
             pass
 
@@ -325,13 +335,14 @@ def stop_application_mode(self) -> None:
             except termios.error:
                 pass
 
-            # Alt screen false, show cursor
-            self.write("\x1b[?1049l" + "\x1b[?25h")
-            self.write("\033[?1004l")  # Disable FocusIn/FocusOut.
-            self.write(
-                "\x1b[<u"
-            )  # Disable https://sw.kovidgoyal.net/kitty/keyboard-protocol/
-            self.flush()
+        # Alt screen false, show cursor
+        self.write("\x1b[?1049l")
+        self.write("\x1b[?25h")
+        self.write("\x1b[?1004l")  # Disable FocusIn/FocusOut.
+        self.write(
+            "\x1b[<u"
+        )  # Disable https://sw.kovidgoyal.net/kitty/keyboard-protocol/
+        self.flush()
 
     def close(self) -> None:
         """Perform cleanup."""
@@ -375,18 +386,26 @@ def more_data() -> bool:
         utf8_decoder = getincrementaldecoder("utf-8")().decode
         decode = utf8_decoder
         read = os.read
+        eof = False
 
         try:
-            while not self.exit_event.is_set():
+            while not eof and not self.exit_event.is_set():
                 selector_events = selector.select(0.1)
                 for _selector_key, mask in selector_events:
                     if mask & EVENT_READ:
                         unicode_data = decode(
                             read(fileno, 1024), final=self.exit_event.is_set()
                         )
+                        if not unicode_data:
+                            # This can occur if the stdin is piped
+                            eof = True
+                            break
                         for event in feed(unicode_data):
                             self.process_event(event)
         finally:
             selector.close()
-            for event in feed(""):
+            try:
+                for event in feed(""):
+                    pass
+            except ParseError:
                 pass

src/textual/message_pump.py

@@ -247,6 +247,8 @@ def app(self) -> "App[object]":
     @property
     def is_attached(self) -> bool:
         """Is this node linked to the app through the DOM?"""
+        if self.app._exit:
+            return False
         node: MessagePump | None = self
         while (node := node._parent) is not None:
             if node.is_dom_root:

src/textual/signal.py

@@ -79,13 +79,13 @@ def subscribe(
 
         if immediate:
 
-            def signal_callback(data: object):
+            def signal_callback(data: object) -> None:
                 """Invoke the callback immediately."""
                 callback(data)
 
         else:
 
-            def signal_callback(data: object):
+            def signal_callback(data: object) -> None:
                 """Post the callback to the node, to call at the next opertunity."""
                 node.call_next(callback, data)
 

src/textual/widget.py

@@ -1005,6 +1005,8 @@ def mount_all(
             Only one of ``before`` or ``after`` can be provided. If both are
             provided a ``MountError`` will be raised.
         """
+        if self.app._exit:
+            return AwaitMount(self, [])
         await_mount = self.mount(*widgets, before=before, after=after)
         return await_mount
 

src/textual/widgets/_footer.py

@@ -172,5 +172,8 @@ async def bindings_changed(screen: Screen) -> None:
 
         self.screen.bindings_updated_signal.subscribe(self, bindings_changed)
 
+    def on_unmount(self) -> None:
+        self.screen.bindings_updated_signal.unsubscribe(self)
+
     def watch_compact(self, compact: bool) -> None:
         self.set_class(compact, "-compact")

src/textual/widgets/_header.py

@@ -7,6 +7,7 @@
 from rich.text import Text
 
 from ..app import RenderResult
+from ..dom import NoScreen
 from ..events import Click, Mount
 from ..reactive import Reactive
 from ..widget import Widget
@@ -213,10 +214,16 @@ def screen_sub_title(self) -> str:
 
     def _on_mount(self, _: Mount) -> None:
         async def set_title() -> None:
-            self.query_one(HeaderTitle).text = self.screen_title
+            try:
+                self.query_one(HeaderTitle).text = self.screen_title
+            except NoScreen:
+                pass
 
         async def set_sub_title() -> None:
-            self.query_one(HeaderTitle).sub_text = self.screen_sub_title
+            try:
+                self.query_one(HeaderTitle).sub_text = self.screen_sub_title
+            except NoScreen:
+                pass
 
         self.watch(self.app, "title", set_title)
         self.watch(self.app, "sub_title", set_sub_title)

tests/deadlock.py

@@ -0,0 +1,21 @@
+"""
+Called by test_pipe.py
+
+"""
+
+from textual.app import App
+from textual.binding import Binding
+from textual.widgets import Footer
+
+
+class MyApp(App[None]):
+    BINDINGS = [
+        Binding(key="q", action="quit", description="Quit the app"),
+    ]
+
+    def compose(self):
+        yield Footer()
+
+
+app = MyApp()
+app.run()

tests/test_pipe.py

@@ -0,0 +1,20 @@
+import subprocess
+import sys
+from pathlib import Path
+
+import pytest
+
+skip_windows = pytest.mark.skipif(
+    sys.platform == "win32", reason="Syntax not supported on Windows"
+)
+
+
+@skip_windows
+def test_deadlock():
+    """Regression test for https://github.com/Textualize/textual/issues/4643"""
+    app_path = (Path(__file__) / "../deadlock.py").resolve().absolute()
+    result = subprocess.run(
+        f'echo q | python "{app_path}"', shell=True, capture_output=True
+    )
+    print(result.stdout)
+    assert result.returncode == 0