feat: undo wiring

codex-rs/core/src/codex.rs

@@ -109,6 +109,7 @@ use crate::tasks::RegularTask;
 use crate::tasks::ReviewTask;
 use crate::tasks::SessionTask;
 use crate::tasks::SessionTaskContext;
+use crate::tasks::UndoTask;
 use crate::tools::ToolRouter;
 use crate::tools::context::SharedTurnDiffTracker;
 use crate::tools::parallel::ToolCallRuntime;
@@ -906,7 +907,7 @@ impl Session {
         state.record_items(items.iter());
     }
 
-    async fn replace_history(&self, items: Vec<ResponseItem>) {
+    pub(crate) async fn replace_history(&self, items: Vec<ResponseItem>) {
         let mut state = self.state.lock().await;
         state.replace_history(items);
     }
@@ -1358,6 +1359,13 @@ async fn submission_loop(sess: Arc<Session>, config: Arc<Config>, rx_sub: Receiv
                 };
                 sess.send_event_raw(event).await;
             }
+            Op::Undo => {
+                let turn_context = sess
+                    .new_turn_with_sub_id(sub.id.clone(), SessionSettingsUpdate::default())
+                    .await;
+                sess.spawn_task(turn_context, Vec::new(), UndoTask::new())
+                    .await;
+            }
             Op::Compact => {
                 let turn_context = sess
                     .new_turn_with_sub_id(sub.id.clone(), SessionSettingsUpdate::default())

codex-rs/core/src/tasks/ghost_snapshot.rs

@@ -10,7 +10,6 @@ use codex_protocol::models::ResponseItem;
 use codex_protocol::user_input::UserInput;
 use codex_utils_readiness::Readiness;
 use codex_utils_readiness::Token;
-use std::borrow::ToOwned;
 use std::sync::Arc;
 use tokio_util::sync::CancellationToken;
 use tracing::info;
@@ -52,8 +51,7 @@ impl SessionTask for GhostSnapshotTask {
                             session
                                 .session
                                 .record_conversation_items(&[ResponseItem::GhostSnapshot {
-                                    commit_id: ghost_commit.id().to_string(),
-                                    parent: ghost_commit.parent().map(ToOwned::to_owned),
+                                    ghost_commit: ghost_commit.clone(),
                                 }])
                                 .await;
                             info!("ghost commit captured: {}", ghost_commit.id());

codex-rs/core/src/tasks/mod.rs

@@ -2,6 +2,7 @@ mod compact;
 mod ghost_snapshot;
 mod regular;
 mod review;
+mod undo;
 
 use std::sync::Arc;
 use std::time::Duration;
@@ -29,6 +30,7 @@ pub(crate) use compact::CompactTask;
 pub(crate) use ghost_snapshot::GhostSnapshotTask;
 pub(crate) use regular::RegularTask;
 pub(crate) use review::ReviewTask;
+pub(crate) use undo::UndoTask;
 
 const GRACEFULL_INTERRUPTION_TIMEOUT_MS: u64 = 100;
 

codex-rs/core/src/tasks/undo.rs

@@ -0,0 +1,117 @@
+use std::sync::Arc;
+
+use crate::codex::TurnContext;
+use crate::protocol::EventMsg;
+use crate::protocol::UndoCompletedEvent;
+use crate::protocol::UndoStartedEvent;
+use crate::state::TaskKind;
+use crate::tasks::SessionTask;
+use crate::tasks::SessionTaskContext;
+use async_trait::async_trait;
+use codex_git_tooling::restore_ghost_commit;
+use codex_protocol::models::ResponseItem;
+use codex_protocol::user_input::UserInput;
+use tokio_util::sync::CancellationToken;
+use tracing::error;
+use tracing::info;
+use tracing::warn;
+
+pub(crate) struct UndoTask;
+
+impl UndoTask {
+    pub(crate) fn new() -> Self {
+        Self
+    }
+}
+
+#[async_trait]
+impl SessionTask for UndoTask {
+    fn kind(&self) -> TaskKind {
+        TaskKind::Regular
+    }
+
+    async fn run(
+        self: Arc<Self>,
+        session: Arc<SessionTaskContext>,
+        ctx: Arc<TurnContext>,
+        _input: Vec<UserInput>,
+        cancellation_token: CancellationToken,
+    ) -> Option<String> {
+        let sess = session.clone_session();
+        sess.send_event(
+            ctx.as_ref(),
+            EventMsg::UndoStarted(UndoStartedEvent {
+                message: Some("Undo in progress...".to_string()),
+            }),
+        )
+        .await;
+
+        if cancellation_token.is_cancelled() {
+            sess.send_event(
+                ctx.as_ref(),
+                EventMsg::UndoCompleted(UndoCompletedEvent {
+                    success: false,
+                    message: Some("Undo cancelled.".to_string()),
+                }),
+            )
+            .await;
+            return None;
+        }
+
+        let mut history = sess.clone_history().await;
+        let mut items = history.get_history();
+        let mut completed = UndoCompletedEvent {
+            success: false,
+            message: None,
+        };
+
+        let Some((idx, ghost_commit)) =
+            items
+                .iter()
+                .enumerate()
+                .rev()
+                .find_map(|(idx, item)| match item {
+                    ResponseItem::GhostSnapshot { ghost_commit } => {
+                        Some((idx, ghost_commit.clone()))
+                    }
+                    _ => None,
+                })
+        else {
+            completed.message = Some("No ghost snapshot available to undo.".to_string());
+            sess.send_event(ctx.as_ref(), EventMsg::UndoCompleted(completed))
+                .await;
+            return None;
+        };
+
+        let commit_id = ghost_commit.id().to_string();
+        let repo_path = ctx.cwd.clone();
+        let restore_result =
+            tokio::task::spawn_blocking(move || restore_ghost_commit(&repo_path, &ghost_commit))
+                .await;
+
+        match restore_result {
+            Ok(Ok(())) => {
+                items.remove(idx);
+                sess.replace_history(items).await;
+                let short_id: String = commit_id.chars().take(7).collect();
+                info!(commit_id = commit_id, "Undo restored ghost snapshot");
+                completed.success = true;
+                completed.message = Some(format!("Undo restored snapshot {short_id}."));
+            }
+            Ok(Err(err)) => {
+                let message = format!("Failed to restore snapshot {commit_id}: {err}");
+                warn!("{message}");
+                completed.message = Some(message);
+            }
+            Err(err) => {
+                let message = format!("Failed to restore snapshot {commit_id}: {err}");
+                error!("{message}");
+                completed.message = Some(message);
+            }
+        }
+
+        sess.send_event(ctx.as_ref(), EventMsg::UndoCompleted(completed))
+            .await;
+        None
+    }
+}

codex-rs/exec/src/event_processor_with_human_output.rs

@@ -20,7 +20,6 @@ use codex_core::protocol::StreamErrorEvent;
 use codex_core::protocol::TaskCompleteEvent;
 use codex_core::protocol::TurnAbortReason;
 use codex_core::protocol::TurnDiffEvent;
-use codex_core::protocol::WebSearchBeginEvent;
 use codex_core::protocol::WebSearchEndEvent;
 use codex_protocol::num_format::format_with_separators;
 use owo_colors::OwoColorize;
@@ -216,7 +215,6 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                     cwd.to_string_lossy(),
                 );
             }
-            EventMsg::ExecCommandOutputDelta(_) => {}
             EventMsg::ExecCommandEnd(ExecCommandEndEvent {
                 aggregated_output,
                 duration,
@@ -283,7 +281,6 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                     }
                 }
             }
-            EventMsg::WebSearchBegin(WebSearchBeginEvent { call_id: _ }) => {}
             EventMsg::WebSearchEnd(WebSearchEndEvent { call_id: _, query }) => {
                 ts_msg!(self, "🌐 Searched: {query}");
             }
@@ -411,12 +408,6 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                 );
                 eprintln!("{unified_diff}");
             }
-            EventMsg::ExecApprovalRequest(_) => {
-                // Should we exit?
-            }
-            EventMsg::ApplyPatchApprovalRequest(_) => {
-                // Should we exit?
-            }
             EventMsg::AgentReasoning(agent_reasoning_event) => {
                 if self.show_agent_reasoning {
                     ts_msg!(
@@ -481,15 +472,6 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                     }
                 }
             }
-            EventMsg::GetHistoryEntryResponse(_) => {
-                // Currently ignored in exec output.
-            }
-            EventMsg::McpListToolsResponse(_) => {
-                // Currently ignored in exec output.
-            }
-            EventMsg::ListCustomPromptsResponse(_) => {
-                // Currently ignored in exec output.
-            }
             EventMsg::ViewImageToolCall(view) => {
                 ts_msg!(
                     self,
@@ -510,15 +492,24 @@ impl EventProcessor for EventProcessorWithHumanOutput {
                 }
             },
             EventMsg::ShutdownComplete => return CodexStatus::Shutdown,
-            EventMsg::ConversationPath(_) => {}
-            EventMsg::UserMessage(_) => {}
-            EventMsg::EnteredReviewMode(_) => {}
-            EventMsg::ExitedReviewMode(_) => {}
-            EventMsg::AgentMessageDelta(_) => {}
-            EventMsg::AgentReasoningDelta(_) => {}
-            EventMsg::AgentReasoningRawContentDelta(_) => {}
-            EventMsg::ItemStarted(_) => {}
-            EventMsg::ItemCompleted(_) => {}
+            EventMsg::WebSearchBegin(_)
+            | EventMsg::ExecApprovalRequest(_)
+            | EventMsg::ApplyPatchApprovalRequest(_)
+            | EventMsg::ExecCommandOutputDelta(_)
+            | EventMsg::GetHistoryEntryResponse(_)
+            | EventMsg::McpListToolsResponse(_)
+            | EventMsg::ListCustomPromptsResponse(_)
+            | EventMsg::ConversationPath(_)
+            | EventMsg::UserMessage(_)
+            | EventMsg::EnteredReviewMode(_)
+            | EventMsg::ExitedReviewMode(_)
+            | EventMsg::AgentMessageDelta(_)
+            | EventMsg::AgentReasoningDelta(_)
+            | EventMsg::AgentReasoningRawContentDelta(_)
+            | EventMsg::ItemStarted(_)
+            | EventMsg::ItemCompleted(_)
+            | EventMsg::UndoCompleted(_)
+            | EventMsg::UndoStarted(_) => {}
         }
         CodexStatus::Running
     }

codex-rs/git-tooling/Cargo.toml

@@ -9,13 +9,20 @@ name = "codex_git_tooling"
 path = "src/lib.rs"
 
 [dependencies]
-tempfile = "3"
-thiserror = "2"
-walkdir = "2"
+tempfile = { workspace = true }
+thiserror = { workspace = true }
+walkdir = { workspace = true }
+schemars = { workspace = true }
+serde = { workspace = true, features = ["derive"] }
+ts-rs = { workspace = true, features = [
+    "uuid-impl",
+    "serde-json-impl",
+    "no-serde-warnings",
+] }
 
 [lints]
 workspace = true
 
 [dev-dependencies]
 assert_matches = { workspace = true }
-pretty_assertions = "1.4.1"
+pretty_assertions = { workspace = true }