Bun Shell

import { spawnSync } from "child_process";

// this is a lot more work than it could be
const { status, stdout, stderr } = spawnSync("ls", ["-l", "*.js"], {
  encoding: "utf8",
});

import { readdir } from "fs/promises";

(await readdir(".", { withFileTypes: true })).filter((a) =>
  a.name.endsWith(".js"),
);

$ hyperfine --warmup 3 'bash -c "echo hello"' 'sh -c "echo hello"' -N

Benchmark 1: bash -c 'echo hello'
  Time (mean ± σ):       7.3 ms ±   1.5 ms    [User: 5.1 ms, System: 1.9 ms]
  Range (min … max):     1.7 ms …   9.4 ms    529 runs

Benchmark 2: sh -c 'echo hello'
  Time (mean ± σ):       7.2 ms ±   1.6 ms    [User: 4.8 ms, System: 2.1 ms]
  Range (min … max):     1.5 ms …   9.6 ms    327 runs

import { $ } from "bun";

// to stdout:
await $`ls *.js`;

// to string:
const text = await $`ls *.js`.text();

import { $ } from "bun";

const resp = await fetch("https://example.com");

const stdout = await $`gzip -c < ${resp}`.arrayBuffer();

const filename = "foo.js; rm -rf /";

// This will run `ls 'foo.js; rm -rf /'`
const results = await $`ls ${filename}`;

console.log(results.exitCode); // 1
console.log(results.stderr.toString()); // ls: cannot access 'foo.js; rm -rf /': No such file or directory

import { $ } from "bun";

const buffer = Buffer.alloc(1024);

await $`ls *.js > ${buffer}`;

console.log(buffer.toString("utf8"));

import { $, file } from "bun";

// as a file()
await $`ls *.js > ${file("output.txt")}`;

// or as a file path string, if you prefer:
await $`ls *.js > output.txt`;
await $`ls *.js > ${"output.txt"}`;

import { $ } from "bun";

await $`ls *.js | grep foo`;

import { $ } from "bun";

const buffer = new Response("bar\n foo\n bar\n foo\n");

await $`grep foo < ${buffer}`;

import { $ } from "bun";

await $`cd .. && rm -rf node_modules/rimraf`;

npm install -g bun