Add the ability to configure rustyline to use a different edit mode (e.g. vi) (#2769)

Co-authored-by: Jack Wright <jack.wright@nike.com>
Co-authored-by: Michael Neale <michael.neale@gmail.com>

crates/goose-cli/src/session/builder.rs

@@ -7,6 +7,7 @@ use goose::recipe::{Response, SubRecipe};
 use goose::session;
 use goose::session::Identifier;
 use mcp_client::transport::Error as McpClientError;
+use rustyline::EditMode;
 use std::process;
 use std::sync::Arc;
 
@@ -136,6 +137,7 @@ async fn offer_extension_debugging_help(
         false,
         None,
         None,
+        None,
     );
 
     // Process the debugging request
@@ -383,6 +385,19 @@ pub async fn build_session(session_config: SessionBuilderConfig) -> Session {
         }
     }
 
+    // Determine editor mode
+    let edit_mode = config
+        .get_param::<String>("EDIT_MODE")
+        .ok()
+        .and_then(|edit_mode| match edit_mode.to_lowercase().as_str() {
+            "emacs" => Some(EditMode::Emacs),
+            "vi" => Some(EditMode::Vi),
+            _ => {
+                eprintln!("Invalid EDIT_MODE specified, defaulting to Emacs");
+                None
+            }
+        });
+
     // Create new session
     let mut session = Session::new(
         agent,
@@ -390,6 +405,7 @@ pub async fn build_session(session_config: SessionBuilderConfig) -> Session {
         session_config.debug,
         session_config.scheduled_job_id.clone(),
         session_config.max_turns,
+        edit_mode,
     );
 
     // Add extensions if provided

crates/goose-cli/src/session/mod.rs

@@ -32,6 +32,7 @@ use mcp_core::protocol::JsonRpcMessage;
 use mcp_core::protocol::JsonRpcNotification;
 
 use rand::{distributions::Alphanumeric, Rng};
+use rustyline::EditMode;
 use serde_json::Value;
 use std::collections::HashMap;
 use std::path::PathBuf;
@@ -54,6 +55,7 @@ pub struct Session {
     run_mode: RunMode,
     scheduled_job_id: Option<String>, // ID of the scheduled job that triggered this session
     max_turns: Option<u32>,
+    edit_mode: Option<EditMode>,
 }
 
 // Cache structure for completion data
@@ -116,6 +118,7 @@ impl Session {
         debug: bool,
         scheduled_job_id: Option<String>,
         max_turns: Option<u32>,
+        edit_mode: Option<EditMode>,
     ) -> Self {
         let messages = if let Some(session_file) = &session_file {
             match session::read_messages(session_file) {
@@ -139,6 +142,7 @@ impl Session {
             run_mode: RunMode::Normal,
             scheduled_job_id,
             max_turns,
+            edit_mode,
         }
     }
 
@@ -399,9 +403,15 @@ impl Session {
         self.update_completion_cache().await?;
 
         // Create a new editor with our custom completer
-        let config = rustyline::Config::builder()
-            .completion_type(rustyline::CompletionType::Circular)
-            .build();
+        let builder =
+            rustyline::Config::builder().completion_type(rustyline::CompletionType::Circular);
+        let builder = if let Some(edit_mode) = self.edit_mode {
+            builder.edit_mode(edit_mode)
+        } else {
+            // Default to Emacs mode if no edit mode is set
+            builder.edit_mode(EditMode::Emacs)
+        };
+        let config = builder.build();
         let mut editor =
             rustyline::Editor::<GooseCompleter, rustyline::history::DefaultHistory>::with_config(
                 config,