Function readFileInRangeStreaming

src/utils/readFileInRange.ts:344–383

(
  filePath: string,
  offset: number,
  maxLines: number | undefined,
  maxBytes: number | undefined,
  truncateOnByteLimit: boolean,
  signal?: AbortSignal,
)

}

function readFileInRangeStreaming(
  filePath: string,
  offset: number,
  maxLines: number | undefined,
  maxBytes: number | undefined,
  truncateOnByteLimit: boolean,
  signal?: AbortSignal,
): Promise<ReadFileRangeResult> {
  return new Promise((resolve, reject) => {
    const state: StreamState = {
      stream: createReadStream(filePath, {
        encoding: 'utf8',
        highWaterMark: 512 * 1024,
        ...(signal ? { signal } : undefined),
      }),
      offset,
      endLine: maxLines !== undefined ? offset + maxLines : Infinity,
      maxBytes,
      truncateOnByteLimit,
      resolve,
      totalBytesRead: 0,
      selectedBytes: 0,
      truncatedByBytes: false,
      currentLineIndex: 0,
      selectedLines: [],
      partial: '',
      isFirstChunk: true,
      resolveMtime: () => {},
      mtimeReady: null as unknown as Promise<number>,
    }
    state.mtimeReady = new Promise<number>(r => {
      state.resolveMtime = r
    })

    state.stream.once('open', streamOnOpen.bind(state))
    state.stream.on('data', streamOnData.bind(state))
    state.stream.once('end', streamOnEnd.bind(state))
    state.stream.once('error', reject)
  })
}