codex-rs(tui): restore EditPrompt arm and clear merge conflict markers in chat_composer

codex-rs/Cargo.lock

@@ -779,6 +779,7 @@ dependencies = [
  "shlex",
  "strum 0.27.1",
  "strum_macros 0.27.1",
+ "tempfile",
  "tokio",
  "tracing",
  "tracing-appender",

codex-rs/config.md

@@ -415,4 +415,8 @@ disable_mouse_capture = true  # defaults to `false`
 # The composer will expand up to this many lines; additional content will enable
 # an internal scrollbar.
 composer_max_rows = 10  # defaults to `10`
+
+# Command used to launch an external editor for composing the chat prompt.
+# Defaults to `$VISUAL`, then `$EDITOR`, falling back to `nvim`.
+editor = "${VISUAL:-${EDITOR:-nvim}}"
 ```

codex-rs/core/src/config_types.rs

@@ -95,17 +95,27 @@ pub struct Tui {
     /// an internal scrollbar.
     #[serde(default = "default_composer_max_rows")]
     pub composer_max_rows: usize,
+    /// Command used to launch the external editor for editing the chat prompt.
+    /// Defaults to the `VISUAL` or `EDITOR` environment variable, falling back to `nvim`.
+    #[serde(default = "default_editor")]
+    pub editor: String,
 }
 
 fn default_composer_max_rows() -> usize {
     10
 }
 
+/// Default editor: `$VISUAL`, then `$EDITOR`, falling back to `nvim`.
+fn default_editor() -> String {
+    std::env::var("VISUAL").or_else(|_| std::env::var("EDITOR")).unwrap_or_else(|_| "nvim".into())
+}
+
 impl Default for Tui {
     fn default() -> Self {
         Self {
             disable_mouse_capture: Default::default(),
             composer_max_rows: default_composer_max_rows(),
+            editor: default_editor(),
         }
     }
 }

codex-rs/tui/Cargo.toml

@@ -39,6 +39,7 @@ serde_json = { version = "1", features = ["preserve_order"] }
 shlex = "1.3.0"
 strum = "0.27.1"
 strum_macros = "0.27.1"
+tempfile = "3"
 tokio = { version = "1", features = [
     "io-std",
     "macros",

codex-rs/tui/src/app.rs

@@ -383,6 +383,9 @@ impl<'a> App<'a> {
                             tracing::error!("Failed to toggle mouse mode: {e}");
                         }
                     }
+                    SlashCommand::EditPrompt => {
+                        // External-editor prompt handled inline by the composer; no-op here.
+                    }
                     SlashCommand::Quit => {
                         break;
                     }

codex-rs/tui/src/bottom_pane/chat_composer.rs

@@ -130,30 +130,8 @@ impl ChatComposer<'_> {
                 }
                 (InputResult::None, true)
             }
-            Input {
-                key: Key::Enter,
-                shift: false,
-                alt: false,
-                ctrl: false,
-            } => {
+            Input { key: Key::Enter, shift: false, alt: false, ctrl: false } => {
                 if let Some(cmd) = popup.selected_command() {
-                    let first_line = self.textarea.lines().first().map_or("", |v| v).to_string();
-                    let args = first_line
-                        .strip_prefix(&format!("/{}", cmd.command()))
-                        .unwrap_or("")
-                        .trim();
-                    if (*cmd == SlashCommand::MountAdd || *cmd == SlashCommand::MountRemove)
-                        && !args.is_empty()
-                    {
-                        let evt = if *cmd == SlashCommand::MountAdd {
-                            AppEvent::InlineMountAdd(args.to_string())
-                        } else {
-                            AppEvent::InlineMountRemove(args.to_string())
-                        };
-                        self.app_event_tx.send(evt);
-                    } else {
-                        self.app_event_tx.send(AppEvent::DispatchCommand(*cmd));
-                    }
                     self.textarea.select_all();
                     self.textarea.cut();
                     self.command_popup = None;
@@ -214,18 +192,16 @@ impl ChatComposer<'_> {
                     (InputResult::Submitted(text), true)
                 }
             }
-            Input {
-                key: Key::Enter, ..
-            }
-            | Input {
-                key: Key::Char('j'),
-                ctrl: true,
-                alt: false,
-                shift: false,
-            } => {
+            Input { key: Key::Enter, .. }
+            | Input { key: Key::Char('j'), ctrl: true, alt: false, shift: false } => {
                 self.textarea.insert_newline();
                 (InputResult::None, true)
             }
+            Input { key: Key::Char('e'), ctrl: true, alt: false, shift: false } => {
+                // Launch external editor for prompt drafting
+                self.open_external_editor();
+                (InputResult::None, true)
+            }
             input => self.handle_input_basic(input),
         }
     }
@@ -236,6 +212,40 @@ impl ChatComposer<'_> {
         (InputResult::None, true)
     }
 
+    /// Launch an external editor on a temporary file pre-populated with the current draft,
+    /// then reload the edited contents back into the textarea on exit.
+    pub fn open_external_editor(&mut self) {
+        use std::io::Write;
+        use std::process::Command;
+        // Dump current draft to a temp file
+        let content = self.textarea.lines().join("\n");
+        let mut tmp = match tempfile::NamedTempFile::new() {
+            Ok(f) => f,
+            Err(e) => {
+                tracing::error!("failed to create temp file for editor: {e}");
+                return;
+            }
+        };
+        if let Err(e) = write!(tmp, "{}", content) {
+            tracing::error!("failed to write to temp file for editor: {e}");
+            return;
+        }
+        let path = tmp.path();
+        // Determine editor: VISUAL > EDITOR > nvim
+        let editor = std::env::var("VISUAL").or_else(|_| std::env::var("EDITOR")).unwrap_or_else(|_| "nvim".into());
+        // Launch editor and wait for exit
+        if let Err(e) = Command::new(editor).arg(path).status() {
+            tracing::error!("failed to launch editor: {e}");
+            return;
+        }
+        // Read back edited contents (fall back to original on error)
+        let new_text = std::fs::read_to_string(path).unwrap_or(content);
+        // Replace textarea contents
+        self.textarea.select_all();
+        self.textarea.cut();
+        let _ = self.textarea.insert_str(new_text);
+    }
+
     /// Synchronize `self.command_popup` with the current text in the
     /// textarea. This must be called after every modification that can change
     /// the text so the popup is shown/updated/hidden as appropriate.

codex-rs/tui/src/slash_command.rs

@@ -14,6 +14,8 @@ use strum_macros::IntoStaticStr;
 pub enum SlashCommand {
     New,
     ToggleMouseMode,
+    /// Launch the external editor to edit the current prompt draft.
+    EditPrompt,
     Quit,
     /// Add a dynamic mount (host path → container path).
     MountAdd,
@@ -28,6 +30,8 @@ impl SlashCommand {
             SlashCommand::New => "Start a new chat.",
             SlashCommand::ToggleMouseMode =>
                 "Toggle mouse mode (enable for scrolling, disable for text selection)",
+            SlashCommand::EditPrompt =>
+                "Open external editor to edit the current prompt.",
             SlashCommand::Quit => "Exit the application.",
             SlashCommand::MountAdd => "Add a mount: host path → container path.",
             SlashCommand::MountRemove => "Remove a mount by container path.",