Fix review activity check during rebase

internal/cli/activity_test.go

@@ -3,6 +3,7 @@ package cli
 import (
 	"context"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"testing"
 
@@ -39,21 +40,48 @@ func TestReviewRunningReportsLiveLockNotPersistedAttempt(t *testing.T) {
 	check(dir, false)
 	other := filepath.Join(t.TempDir(), "checkout")
 	git(t, dir, "worktree", "add", "-b", "other", other, "HEAD")
+	pause := func(cwd string) {
+		t.Helper()
+		cmd := exec.Command("git", "rebase", "--force-rebase", "--exec", "false", "HEAD~1")
+		cmd.Dir = cwd
+		output, err := cmd.CombinedOutput()
+		require.Error(t, err, string(output))
+		require.Empty(t, git(t, cwd, "branch", "--show-current"))
+	}
 	called := false
 	reviewer := review.Reviewer{
 		Service: review.Service{Repository: review.Repository{Dir: dir}},
 		Choose: func(context.Context, *review.Decision) (string, error) {
 			called = true
 			check(dir, true)
 			check(other, false)
+			// A paused replay must still identify its branch, including in a
+			// linked worktree, without treating another branch's lock as its own.
+			pause(dir)
+			pause(other)
+			check(dir, true)
+			check(other, false)
+			git(t, dir, "rebase", "--abort")
+			git(t, other, "rebase", "--abort")
 			return "cancel", nil
 		},
 	}
 	_, err = reviewer.Review(t.Context(), review.ReviewOptions{})
 	require.NoError(t, err)
 	require.True(t, called)
+	pause(dir)
+	pause(other)
 	check(dir, false)
 	check(other, false)
+	for _, cwd := range []string{dir, other} {
+		git(t, cwd, "rebase", "--abort")
+	}
+	// A detached checkout without rebase metadata has no branch to check.
+	git(t, dir, "checkout", "--detach")
+	out, terminal, err := executeBinary(t, binary, dir, "running", "--json")
+	require.Error(t, err)
+	require.Empty(t, terminal)
+	require.Contains(t, out, `"status":"error"`)
 }
 
 func TestReviewRunningOutsideRepository(t *testing.T) {

internal/review/git.go

@@ -4,6 +4,7 @@ package review
 import (
 	"context"
 	"crypto/sha256"
+	"errors"
 	"fmt"
 	"os"
 	"os/exec"
@@ -148,6 +149,40 @@ func (r Repository) Snapshot(ctx context.Context) (Snapshot, error) {
 	return view, nil
 }
 
+// reviewBranch identifies the branch whose review lock applies during a replay.
+// Other review commands still require an attached HEAD through branchView.
+func (r Repository) reviewBranch(ctx context.Context) (string, error) {
+	branch, err := r.git(ctx, "symbolic-ref", "--quiet", "HEAD")
+	if err == nil {
+		return branch, nil
+	}
+	if exit, ok := errors.AsType[*exec.ExitError](err); !ok || exit.ExitCode() != 1 {
+		return "", err
+	}
+	for _, backend := range []string{"rebase-merge", "rebase-apply"} {
+		path, pathErr := r.git(ctx, "rev-parse", "--path-format=absolute", "--git-path", backend+"/head-name")
+		if pathErr != nil {
+			return "", pathErr
+		}
+		data, readErr := os.ReadFile(path)
+		if errors.Is(readErr, os.ErrNotExist) {
+			continue
+		}
+		if readErr != nil {
+			return "", readErr
+		}
+		branch = strings.TrimSpace(string(data))
+		if !strings.HasPrefix(branch, "refs/heads/") {
+			return "", fmt.Errorf("rebase does not identify a local branch")
+		}
+		if _, err := r.git(ctx, "check-ref-format", branch); err != nil {
+			return "", err
+		}
+		return branch, nil
+	}
+	return "", err
+}
+
 func (r Repository) branchView(ctx context.Context) (Snapshot, string, error) {
 	var view Snapshot
 	repo, err := r.git(ctx, "rev-parse", "--show-toplevel")

internal/review/service.go

@@ -124,14 +124,14 @@ func (s Service) Feedback(ctx context.Context) (Result, error) {
 	return result, nil
 }
 
-// ReviewRunning reports whether the current branch owns the live review lock.
+// ReviewRunning reports whether the current or rebasing branch owns the live review lock.
 // It does not create the lock file or infer activity from persisted attempts.
 func (s Service) ReviewRunning(ctx context.Context) (bool, error) {
 	path, err := WorktreePath(s.Repository.Dir)
 	if err != nil {
 		return false, err
 	}
-	branch, err := s.Repository.git(ctx, "symbolic-ref", "--quiet", "HEAD")
+	branch, err := s.Repository.reviewBranch(ctx)
 	if err != nil {
 		return false, err
 	}