node/test/parallel/test-debugger-util-regression.js

'use strict';
const path = require('path');
const spawn = require('child_process').spawn;
const assert = require('assert');

const common = require('../common');

const fixture = path.join(
  common.fixturesDir,
  'debugger-util-regression-fixture.js'
);

const args = [
  'debug',
  `--port=${common.PORT}`,
  fixture
];

const proc = spawn(process.execPath, args, { stdio: 'pipe' });
proc.stdout.setEncoding('utf8');
proc.stderr.setEncoding('utf8');

function fail() {
  common.fail('the program should not hang');
}

const timer = setTimeout(fail, common.platformTimeout(4000));

let stdout = '';
let stderr = '';

let nextCount = 0;

proc.stdout.on('data', (data) => {
  stdout += data;
  if (stdout.includes('> 1') && nextCount < 1 ||
      stdout.includes('> 2') && nextCount < 2 ||
      stdout.includes('> 3') && nextCount < 3 ||
      stdout.includes('> 4') && nextCount < 4) {
    nextCount++;
    proc.stdin.write('n\n');
  }
  else if (stdout.includes('{ a: \'b\' }')) {
    clearTimeout(timer);
    proc.stdin.write('.exit\n');
  }
  else if (stdout.includes('program terminated')) {
    // Catch edge case present in v4.x
    // process will terminate after call to util.inspect
    common.fail('the program should not terminate');
  }
});

proc.stderr.on('data', (data) => stderr += data);

// FIXME
// This test has been periodically failing on certain systems due to
// uncaught errors on proc.stdin. This will stop the process from
// exploding but is still not an elegant solution. Likely a deeper bug
// causing this problem.
proc.stdin.on('error', (err) => {
  console.error(err);
});

process.on('exit', (code) => {
  assert.equal(code, 0, 'the program should exit cleanly');
  assert.equal(stdout.includes('{ a: \'b\' }'), true,
      'the debugger should print the result of util.inspect');
  assert.equal(stderr, '', 'stderr should be empty');
});