Function createSubcommandPrefixExtractor

src/utils/shell/prefix.ts:138–170

(
  getPrefix: ReturnType<typeof createCommandPrefixExtractor>,
  splitCommand: (command: string) => string[] | Promise<string[]>,
)

 * @returns A memoized async function that extracts prefixes for the main command and all subcommands
 */
export function createSubcommandPrefixExtractor(
  getPrefix: ReturnType<typeof createCommandPrefixExtractor>,
  splitCommand: (command: string) => string[] | Promise<string[]>,
) {
  const memoized = memoizeWithLRU(
    (
      command: string,
      abortSignal: AbortSignal,
      isNonInteractiveSession: boolean,
    ): Promise<CommandSubcommandPrefixResult | null> => {
      const promise = getCommandSubcommandPrefixImpl(
        command,
        abortSignal,
        isNonInteractiveSession,
        getPrefix,
        splitCommand,
      )
      // Evict on rejection so aborted calls don't poison future turns.
      // Identity guard: after LRU eviction, a newer promise may occupy
      // this key; a stale rejection must not delete it.
      promise.catch(() => {
        if (memoized.cache.get(command) === promise) {
          memoized.cache.delete(command)
        }
      })
      return promise
    },
    command => command, // memoize by command only
    200,
  )

  return memoized
}

async function getCommandPrefixImpl(
  command: string,