# PR #1766: Supporting both shift+enter and ctrl+j and adding kpp check + unit test
- URL: https://github.com/openai/codex/pull/1766
- Author: pap-openai
- Created: 2025-07-31 21:05:22 UTC
- Updated: 2025-08-01 00:32:14 UTC
- Changes: +98/-1, Files changed: 5, Commits: 8
## Description
Apple terminal shows ctrl+j
iTerm that supports KPP shows shift+enter
## Full Diff
```diff
diff --git a/codex-rs/Cargo.lock b/codex-rs/Cargo.lock
index 87d59b21be..e6b5c11bd9 100644
--- a/codex-rs/Cargo.lock
+++ b/codex-rs/Cargo.lock
@@ -854,6 +854,7 @@ dependencies = [
"image",
"insta",
"lazy_static",
+ "libc",
"mcp-types",
"path-clean",
"pretty_assertions",
diff --git a/codex-rs/tui/Cargo.toml b/codex-rs/tui/Cargo.toml
index 63d287ca11..e5739ec505 100644
--- a/codex-rs/tui/Cargo.toml
+++ b/codex-rs/tui/Cargo.toml
@@ -32,6 +32,7 @@ color-eyre = "0.6.3"
crossterm = { version = "0.28.1", features = ["bracketed-paste"] }
image = { version = "^0.25.6", default-features = false, features = ["jpeg"] }
lazy_static = "1"
+libc = "0.2"
mcp-types = { path = "../mcp-types" }
path-clean = "1.0.1"
ratatui = { version = "0.29.0", features = [
diff --git a/codex-rs/tui/src/bottom_pane/chat_composer.rs b/codex-rs/tui/src/bottom_pane/chat_composer.rs
index 3bc573a003..6b7017f6f0 100644
--- a/codex-rs/tui/src/bottom_pane/chat_composer.rs
+++ b/codex-rs/tui/src/bottom_pane/chat_composer.rs
@@ -712,11 +712,16 @@ impl WidgetRef for &ChatComposer<'_> {
Span::from(" to quit"),
]
} else {
+ let newline_hint = if crate::tui::is_kkp_enabled() {
+ "Shift+⏎"
+ } else {
+ "Ctrl+J"
+ };
vec![
Span::from(" "),
"⏎".set_style(key_hint_style),
Span::from(" send "),
- "Shift+⏎".set_style(key_hint_style),
+ newline_hint.set_style(key_hint_style),
Span::from(" newline "),
"Ctrl+C".set_style(key_hint_style),
Span::from(" quit"),
@@ -961,6 +966,9 @@ mod tests {
use ratatui::Terminal;
use ratatui::backend::TestBackend;
+ // First, run snapshots with KKP enabled so hints show Shift+⏎.
+ crate::tui::set_kkp_for_tests(true);
+
let (tx, _rx) = std::sync::mpsc::channel();
let sender = AppEventSender::new(tx);
let mut terminal = match Terminal::new(TestBackend::new(100, 10)) {
@@ -1005,6 +1013,18 @@ mod tests {
assert_snapshot!(name, terminal.backend());
}
+
+ // Also add one snapshot with KKP disabled so we still see Ctrl+J.
+ crate::tui::set_kkp_for_tests(false);
+ let mut terminal_ctrlj = match Terminal::new(TestBackend::new(100, 10)) {
+ Ok(t) => t,
+ Err(e) => panic!("Failed to create terminal: {e}"),
+ };
+ let composer = ChatComposer::new(true, sender.clone());
+ terminal_ctrlj
+ .draw(|f| f.render_widget_ref(&composer, f.area()))
+ .unwrap_or_else(|e| panic!("Failed to draw empty_ctrlj composer: {e}"));
+ assert_snapshot!("empty_ctrlj", terminal_ctrlj.backend());
}
#[test]
diff --git a/codex-rs/tui/src/bottom_pane/snapshots/codex_tui__bottom_pane__chat_composer__tests__empty_ctrlj.snap b/codex-rs/tui/src/bottom_pane/snapshots/codex_tui__bottom_pane__chat_composer__tests__empty_ctrlj.snap
new file mode 100644
index 0000000000..f798f1af16
--- /dev/null
+++ b/codex-rs/tui/src/bottom_pane/snapshots/codex_tui__bottom_pane__chat_composer__tests__empty_ctrlj.snap
@@ -0,0 +1,14 @@
+---
+source: tui/src/bottom_pane/chat_composer.rs
+expression: terminal_ctrlj.backend()
+---
+"▌ ... "
+"▌ "
+"▌ "
+"▌ "
+"▌ "
+"▌ "
+"▌ "
+"▌ "
+"▌ "
+" ⏎ send Ctrl+J newline Ctrl+C quit "
diff --git a/codex-rs/tui/src/tui.rs b/codex-rs/tui/src/tui.rs
index 268483cbcf..81ec9aebdc 100644
--- a/codex-rs/tui/src/tui.rs
+++ b/codex-rs/tui/src/tui.rs
@@ -1,6 +1,8 @@
use std::io::Result;
use std::io::Stdout;
use std::io::stdout;
+use std::sync::atomic::AtomicBool;
+use std::sync::atomic::Ordering;
use codex_core::config::Config;
use crossterm::event::DisableBracketedPaste;
@@ -18,6 +20,60 @@ use crate::custom_terminal::Terminal;
/// A type alias for the terminal type used in this application
pub type Tui = Terminal>;
+// Global flag indicating whether Kitty Keyboard Protocol (KKP) appears enabled.
+static KKP_ENABLED: AtomicBool = AtomicBool::new(false);
+
+/// Return whether KKP (alternate key reporting) appears enabled.
+pub(crate) fn is_kkp_enabled() -> bool {
+ KKP_ENABLED.load(Ordering::Relaxed)
+}
+
+#[cfg(test)]
+pub(crate) fn set_kkp_for_tests(value: bool) {
+ KKP_ENABLED.store(value, Ordering::Relaxed);
+}
+
+/// Try to detect Kitty Keyboard Protocol support by issuing a progressive
+/// enhancement query and waiting briefly for a response.
+#[cfg(unix)]
+fn detect_kitty_protocol() -> std::io::Result {
+ use std::io::Read;
+ use std::io::Write;
+ use std::io::{self};
+ use std::os::unix::io::AsRawFd;
+
+ let mut stdout = io::stdout();
+ let mut stdin = io::stdin();
+
+ // Send query for progressive enhancement + DA1
+ write!(stdout, "\x1b[?u\x1b[c")?;
+ stdout.flush()?;
+
+ // Wait up to ~200ms for a response
+ let fd = stdin.as_raw_fd();
+ let mut pfd = libc::pollfd {
+ fd,
+ events: libc::POLLIN,
+ revents: 0,
+ };
+ let rc = unsafe { libc::poll(&mut pfd as *mut libc::pollfd, 1, 200) };
+ if rc > 0 && (pfd.revents & libc::POLLIN) != 0 {
+ let mut buf = [0u8; 256];
+ if let Ok(n) = stdin.read(&mut buf) {
+ let response = String::from_utf8_lossy(&buf[..n]);
+ if response.contains("[?") && response.contains('u') {
+ return Ok(true);
+ }
+ }
+ }
+ Ok(false)
+}
+
+#[cfg(not(unix))]
+fn detect_kitty_protocol() -> std::io::Result {
+ Ok(false)
+}
+
/// Initialize the terminal (inline viewport; history stays in normal scrollback)
pub fn init(_config: &Config) -> Result {
execute!(stdout(), EnableBracketedPaste)?;
@@ -34,6 +90,11 @@ pub fn init(_config: &Config) -> Result {
| KeyboardEnhancementFlags::REPORT_ALTERNATE_KEYS
)
)?;
+
+ // Detect KKP availability; used to adjust UI hints in the composer.
+ let kkp = detect_kitty_protocol().unwrap_or(false);
+ KKP_ENABLED.store(kkp, Ordering::Relaxed);
+
set_panic_hook();
let backend = CrosstermBackend::new(stdout());
```
## Review Comments
### codex-rs/tui/src/tui.rs
- Created: 2025-08-01 00:17:33 UTC | Link: https://github.com/openai/codex/pull/1766#discussion_r2246611560
```diff
@@ -18,6 +20,60 @@ use crate::custom_terminal::Terminal;
/// A type alias for the terminal type used in this application
pub type Tui = Terminal>;
+// Global flag indicating whether Kitty Keyboard Protocol (KKP) appears enabled.
+static KKP_ENABLED: AtomicBool = AtomicBool::new(false);
```
> This feels like we are going to end up with flaky tests due to race conditions?