chore: move pty and windows sandbox to Rust 2024 (#15954)

## Why

`codex-utils-pty` and `codex-windows-sandbox` were the remaining crates
in `codex-rs` that still overrode the workspace's Rust 2024 edition.
Moving them forward in a separate PR keeps the baseline edition update
isolated from the follow-on Bazel clippy workflow in #15955, while
making linting and formatting behavior consistent with the rest of the
workspace.

This PR also needs Cargo and Bazel to agree on the edition for
`codex-windows-sandbox`. Without the Bazel-side sync, the experimental
Bazel app-server builds fail once they compile `windows-sandbox-rs`.

## What changed

- switch `codex-rs/utils/pty` and `codex-rs/windows-sandbox-rs` to
`edition = "2024"`
- update `codex-utils-pty` callsites and tests to use the collapsed `if
let` form that Clippy expects under the new edition
- fix the Rust 2024 fallout in `windows-sandbox-rs`, including the
reserved `gen` identifier, `unsafe extern` requirements, and new Clippy
findings that surfaced under the edition bump
- keep the edition bump separate from a larger unsafe cleanup by
temporarily allowing `unsafe_op_in_unsafe_fn` in the Windows entrypoint
modules that now report it under Rust 2024
- update `codex-rs/windows-sandbox-rs/BUILD.bazel` to `crate_edition =
"2024"` so Bazel compiles the crate with the same edition as Cargo





---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/15954).
* #15976
* #15955
* __->__ #15954

codex-rs/utils/pty/src/lib.rs

@@ -13,14 +13,14 @@ pub const DEFAULT_OUTPUT_BYTES_CAP: usize = 1024 * 1024;
 pub use pipe::spawn_process as spawn_pipe_process;
 /// Spawn a non-interactive process using regular pipes, but close stdin immediately.
 pub use pipe::spawn_process_no_stdin as spawn_pipe_process_no_stdin;
-/// Combine stdout/stderr receivers into a single broadcast receiver.
-pub use process::combine_output_receivers;
 /// Handle for interacting with a spawned process (PTY or pipe).
 pub use process::ProcessHandle;
 /// Bundle of process handles plus split output and exit receivers returned by spawn helpers.
 pub use process::SpawnedProcess;
 /// Terminal size in character cells used for PTY spawn and resize operations.
 pub use process::TerminalSize;
+/// Combine stdout/stderr receivers into a single broadcast receiver.
+pub use process::combine_output_receivers;
 /// Backwards-compatible alias for ProcessHandle.
 pub type ExecCommandSession = ProcessHandle;
 /// Backwards-compatible alias for SpawnedProcess.

codex-rs/utils/pty/src/pipe.rs

@@ -3,9 +3,9 @@ use std::io;
 use std::io::ErrorKind;
 use std::path::Path;
 use std::process::Stdio;
-use std::sync::atomic::AtomicBool;
 use std::sync::Arc;
 use std::sync::Mutex as StdMutex;
+use std::sync::atomic::AtomicBool;
 
 use anyhow::Result;
 use tokio::io::AsyncRead;
@@ -64,11 +64,7 @@ fn kill_process(pid: u32) -> io::Result<()> {
         let success = winapi::um::processthreadsapi::TerminateProcess(handle, 1);
         let err = io::Error::last_os_error();
         winapi::um::handleapi::CloseHandle(handle);
-        if success == 0 {
-            Err(err)
-        } else {
-            Ok(())
-        }
+        if success == 0 { Err(err) } else { Ok(()) }
     }
 }
 

codex-rs/utils/pty/src/process.rs

@@ -2,9 +2,9 @@ use core::fmt;
 use std::io;
 #[cfg(unix)]
 use std::os::fd::RawFd;
-use std::sync::atomic::AtomicBool;
 use std::sync::Arc;
 use std::sync::Mutex as StdMutex;
+use std::sync::atomic::AtomicBool;
 
 use anyhow::anyhow;
 use portable_pty::MasterPty;
@@ -118,10 +118,10 @@ impl ProcessHandle {
 
     /// Returns a channel sender for writing raw bytes to the child stdin.
     pub fn writer_sender(&self) -> mpsc::Sender<Vec<u8>> {
-        if let Ok(writer_tx) = self.writer_tx.lock() {
-            if let Some(writer_tx) = writer_tx.as_ref() {
-                return writer_tx.clone();
-            }
+        if let Ok(writer_tx) = self.writer_tx.lock()
+            && let Some(writer_tx) = writer_tx.as_ref()
+        {
+            return writer_tx.clone();
         }
 
         let (writer_tx, writer_rx) = mpsc::channel(1);
@@ -165,10 +165,10 @@ impl ProcessHandle {
     /// Attempts to kill the child while leaving the reader/writer tasks alive
     /// so callers can still drain output until EOF.
     pub fn request_terminate(&self) {
-        if let Ok(mut killer_opt) = self.killer.lock() {
-            if let Some(mut killer) = killer_opt.take() {
-                let _ = killer.kill();
-            }
+        if let Ok(mut killer_opt) = self.killer.lock()
+            && let Some(mut killer) = killer_opt.take()
+        {
+            let _ = killer.kill();
         }
     }
 
@@ -176,25 +176,25 @@ impl ProcessHandle {
     pub fn terminate(&self) {
         self.request_terminate();
 
-        if let Ok(mut h) = self.reader_handle.lock() {
-            if let Some(handle) = h.take() {
-                handle.abort();
-            }
+        if let Ok(mut h) = self.reader_handle.lock()
+            && let Some(handle) = h.take()
+        {
+            handle.abort();
         }
         if let Ok(mut handles) = self.reader_abort_handles.lock() {
             for handle in handles.drain(..) {
                 handle.abort();
             }
         }
-        if let Ok(mut h) = self.writer_handle.lock() {
-            if let Some(handle) = h.take() {
-                handle.abort();
-            }
+        if let Ok(mut h) = self.writer_handle.lock()
+            && let Some(handle) = h.take()
+        {
+            handle.abort();
         }
-        if let Ok(mut h) = self.wait_handle.lock() {
-            if let Some(handle) = h.take() {
-                handle.abort();
-            }
+        if let Ok(mut h) = self.wait_handle.lock()
+            && let Some(handle) = h.take()
+        {
+            handle.abort();
         }
     }
 }

codex-rs/utils/pty/src/pty.rs

@@ -15,15 +15,15 @@ use std::path::Path;
 use std::process::Command as StdCommand;
 #[cfg(unix)]
 use std::process::Stdio;
-use std::sync::atomic::AtomicBool;
 use std::sync::Arc;
 use std::sync::Mutex as StdMutex;
+use std::sync::atomic::AtomicBool;
 use std::time::Duration;
 
 use anyhow::Result;
+use portable_pty::CommandBuilder;
 #[cfg(not(windows))]
 use portable_pty::native_pty_system;
-use portable_pty::CommandBuilder;
 use tokio::sync::mpsc;
 use tokio::sync::oneshot;
 use tokio::task::JoinHandle;

codex-rs/utils/pty/src/tests.rs

@@ -3,6 +3,8 @@ use std::path::Path;
 
 use pretty_assertions::assert_eq;
 
+use crate::SpawnedProcess;
+use crate::TerminalSize;
 use crate::combine_output_receivers;
 #[cfg(unix)]
 use crate::pipe::spawn_process_no_stdin_with_inherited_fds;
@@ -11,18 +13,15 @@ use crate::pty::spawn_process_with_inherited_fds;
 use crate::spawn_pipe_process;
 use crate::spawn_pipe_process_no_stdin;
 use crate::spawn_pty_process;
-use crate::SpawnedProcess;
-use crate::TerminalSize;
 
 fn find_python() -> Option<String> {
     for candidate in ["python3", "python"] {
         if let Ok(output) = std::process::Command::new(candidate)
             .arg("--version")
             .output()
+            && output.status.success()
         {
-            if output.status.success() {
-                return Some(candidate.to_string());
-            }
+            return Some(candidate.to_string());
         }
     }
     None
@@ -855,8 +854,7 @@ async fn pty_spawn_with_inherited_fds_supports_resize() -> anyhow::Result<()> {
     let write_end = unsafe { std::fs::File::from_raw_fd(fds[1]) };
 
     let env_map: HashMap<String, String> = std::env::vars().collect();
-    let script =
-        "stty -echo; printf 'start:%s\\n' \"$(stty size)\"; IFS= read _line; printf 'after:%s\\n' \"$(stty size)\"";
+    let script = "stty -echo; printf 'start:%s\\n' \"$(stty size)\"; IFS= read _line; printf 'after:%s\\n' \"$(stty size)\"";
     let spawned = spawn_process_with_inherited_fds(
         "/bin/sh",
         &["-c".to_string(), script.to_string()],

codex-rs/utils/pty/src/win/conpty.rs

@@ -22,13 +22,13 @@ use crate::win::psuedocon::PsuedoCon;
 use anyhow::Error;
 use filedescriptor::FileDescriptor;
 use filedescriptor::Pipe;
-use portable_pty::cmdbuilder::CommandBuilder;
 use portable_pty::Child;
 use portable_pty::MasterPty;
 use portable_pty::PtyPair;
 use portable_pty::PtySize;
 use portable_pty::PtySystem;
 use portable_pty::SlavePty;
+use portable_pty::cmdbuilder::CommandBuilder;
 use std::mem::ManuallyDrop;
 use std::os::windows::io::AsRawHandle;
 use std::os::windows::io::RawHandle;

codex-rs/utils/pty/src/win/mod.rs

@@ -142,11 +142,7 @@ impl Child for WinChild {
 
     fn process_id(&self) -> Option<u32> {
         let res = unsafe { GetProcessId(self.proc.lock().unwrap().as_raw_handle() as _) };
-        if res == 0 {
-            None
-        } else {
-            Some(res)
-        }
+        if res == 0 { None } else { Some(res) }
     }
 
     fn as_raw_handle(&self) -> Option<std::os::windows::io::RawHandle> {

codex-rs/utils/pty/src/win/procthreadattr.rs

@@ -19,8 +19,8 @@
 // SOFTWARE.
 
 use super::psuedocon::HPCON;
-use anyhow::ensure;
 use anyhow::Error;
+use anyhow::ensure;
 use std::io::Error as IoError;
 use std::mem;
 use std::ptr;

codex-rs/utils/pty/src/win/psuedocon.rs

@@ -21,9 +21,9 @@
 
 use super::WinChild;
 use crate::win::procthreadattr::ProcThreadAttributeList;
+use anyhow::Error;
 use anyhow::bail;
 use anyhow::ensure;
-use anyhow::Error;
 use filedescriptor::FileDescriptor;
 use filedescriptor::OwnedHandle;
 use lazy_static::lazy_static;
@@ -356,8 +356,8 @@ fn append_quoted(arg: &OsStr, cmdline: &mut Vec<u16>) {
 
 #[cfg(test)]
 mod tests {
-    use super::windows_build_number;
     use super::MIN_CONPTY_BUILD;
+    use super::windows_build_number;
 
     #[test]
     fn windows_build_number_returns_value() {