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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
import { Buffer } from "../io/buffer.ts";import { writeAll } from "./write_all.ts";
/** * Create a `Reader` from a `ReadableStreamDefaultReader`. * * @example * ```ts * import { copy } from "https://deno.land/std@$STD_VERSION/streams/copy.ts"; * import { readerFromStreamReader } from "https://deno.land/std@$STD_VERSION/streams/reader_from_stream_reader.ts"; * * const res = await fetch("https://deno.land"); * const file = await Deno.open("./deno.land.html", { create: true, write: true }); * * const reader = readerFromStreamReader(res.body!.getReader()); * await copy(reader, file); * file.close(); * ``` */export function readerFromStreamReader(  streamReader: ReadableStreamDefaultReader<Uint8Array>,): Deno.Reader {  const buffer = new Buffer();
  return {    async read(p: Uint8Array): Promise<number | null> {      if (buffer.empty()) {        const res = await streamReader.read();        if (res.done) {          return null; // EOF        }
        await writeAll(buffer, res.value);      }
      return buffer.read(p);    },  };}