Function saveWorktreeState

src/utils/sessionStorage.ts:3069–3100

(
  worktreeSession: PersistedWorktreeSession | null,
)

 * so --resume knows not to cd back into it.
 */
export function saveWorktreeState(
  worktreeSession: PersistedWorktreeSession | null,
): void {
  // Strip ephemeral fields (creationDurationMs, usedSparsePaths) that callers
  // may pass via full WorktreeSession objects — TypeScript structural typing
  // allows this, but we don't want them serialized to the transcript.
  const stripped: PersistedWorktreeSession | null = worktreeSession
    ? {
        originalCwd: worktreeSession.originalCwd,
        worktreePath: worktreeSession.worktreePath,
        worktreeName: worktreeSession.worktreeName,
        worktreeBranch: worktreeSession.worktreeBranch,
        originalBranch: worktreeSession.originalBranch,
        originalHeadCommit: worktreeSession.originalHeadCommit,
        sessionId: worktreeSession.sessionId,
        tmuxSessionName: worktreeSession.tmuxSessionName,
        hookBased: worktreeSession.hookBased,
      }
    : null
  const project = getProject()
  project.currentSessionWorktree = stripped
  // Write eagerly when the file already exists (mid-session enter/exit).
  // For --worktree startup, sessionFile is null — materializeSessionFile
  // will write it on the first message via reAppendSessionMetadata.
  if (project.sessionFile) {
    appendEntryToFile(project.sessionFile, {
      type: 'worktree-state',
      worktreeSession: stripped,
      sessionId: getSessionId(),
    })
  }
}

/**
 * Extracts the session ID from a log.