Function findModifiedFiles

src/utils/filePersistence/outputsScanner.ts:73–137

(
  turnStartTime: TurnStartTime,
  outputsDir: string,
)

 * @param outputsDir - The directory to scan for modified files
 */
export async function findModifiedFiles(
  turnStartTime: TurnStartTime,
  outputsDir: string,
): Promise<string[]> {
  // Use recursive flag to get all entries in one call
  let entries: Awaited<ReturnType<typeof fs.readdir>>
  try {
    entries = await fs.readdir(outputsDir, {
      withFileTypes: true,
      recursive: true,
    })
  } catch {
    // Directory doesn't exist or is not accessible
    return []
  }

  // Filter to regular files only (skip symlinks for security) and build full paths
  const filePaths: string[] = []
  for (const entry of entries) {
    if (entry.isSymbolicLink()) {
      continue
    }
    if (entry.isFile()) {
      // entry.parentPath is available in Node 20+, fallback to entry.path for older versions
      const parentPath = getEntryParentPath(entry, outputsDir)
      filePaths.push(path.join(parentPath, entry.name))
    }
  }

  if (filePaths.length === 0) {
    logDebug('No files found in outputs directory')
    return []
  }

  // Parallelize stat calls for all files
  const statResults = await Promise.all(
    filePaths.map(async filePath => {
      try {
        const stat = await fs.lstat(filePath)
        // Skip if it became a symlink between readdir and stat (race condition)
        if (stat.isSymbolicLink()) {
          return null
        }
        return { filePath, mtimeMs: stat.mtimeMs }
      } catch {
        // File may have been deleted between readdir and stat
        return null
      }
    }),
  )

  // Filter to files modified since turn start
  const modifiedFiles: string[] = []
  for (const result of statResults) {
    if (result && result.mtimeMs >= turnStartTime) {
      modifiedFiles.push(result.filePath)
    }
  }