import { createReadStream, createWriteStream, readFileSync } from "fs"; await new Promise((resolve, reject) => { createReadStream("fs-stream.js") .pipe(createWriteStream("/tmp/fs-stream.copy.js")) .once("error", err => reject(err)) .once("finish", () => { try { const copied = readFileSync("/tmp/fs-stream.copy.js", "utf8"); const real = readFileSync("/tmp/fs-stream.js", "utf8"); if (copied !== real) { reject(new Error("fs-stream.js is not the same as fs-stream.copy.js")); return; } resolve(true); } catch (err) { reject(err); } }); });