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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license./** * A `LimitedReader` reads from `reader` but limits the amount of data returned to just `limit` bytes. * Each call to `read` updates `limit` to reflect the new amount remaining. * `read` returns `null` when `limit` <= `0` or * when the underlying `reader` returns `null`. */import type { Reader } from "../types.d.ts";
export class LimitedReader implements Reader {  constructor(public reader: Reader, public limit: number) {}
  async read(p: Uint8Array): Promise<number | null> {    if (this.limit <= 0) {      return null;    }
    if (p.length > this.limit) {      p = p.subarray(0, this.limit);    }    const n = await this.reader.read(p);    if (n == null) {      return null;    }
    this.limit -= n;    return n;  }}