const { execFileSync } = require('node:child_process');
const fs = require('node:fs');
const path = require('node:path');
const os = require('node:os');

// 1. Create a "fake" binary in a temp directory
const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'bun-path-test-'));
const fakeBinaryPath = path.join(tmpDir, 'ls');
fs.writeFileSync(fakeBinaryPath, '#!/bin/sh\necho "FAKE_CALLED"', { mode: 0o755 });

// 2. Prepend the temp directory to PATH at runtime
const originalPath = process.env.PATH;
process.env.PATH = `${tmpDir}${path.delimiter}${originalPath}`;

console.log(`Current process.env.PATH starts with: ${process.env.PATH.split(path.delimiter)[0]}`);

try {
  // 3. Attempt to call 'ls' without an explicit env option
  // Expected (Node.js behavior): Resolves to our fake binary and prints "FAKE_CALLED"
  // Actual (Bun behavior): Resolves to /bin/ls and prints real directory listing
  const output = execFileSync('ls', { encoding: 'utf8' }).split('\n')[0];
  console.log(`Result (omitted env): ${output}`);

  // 4. Attempt to call 'ls' with explicit env: process.env
  // This works in both runtimes
  const outputWithEnv = execFileSync('ls', { encoding: 'utf8', env: process.env }).split('\n')[0];
  console.log(`Result (explicit env): ${outputWithEnv}`);

} finally {
  // Cleanup
  fs.rmSync(tmpDir, { recursive: true, force: true });
}