/* eslint-disable node-core/required-modules */

'use strict';

const assert = require('assert');
const fork = require('child_process').fork;
const path = require('path');

const runjs = path.join(__dirname, '..', '..', 'benchmark', 'run.js');

function runBenchmark(name, args, env) {
  const argv = [];

  for (let i = 0; i < args.length; i++) {
    argv.push('--set');
    argv.push(args[i]);
  }

  argv.push(name);

  const mergedEnv = Object.assign({}, process.env, env);

  const child = fork(runjs, argv, {
    env: mergedEnv,
    stdio: ['inherit', 'pipe', 'inherit', 'ipc']
  });
  child.stdout.setEncoding('utf8');

  let stdout = '';
  child.stdout.on('data', (line) => {
    stdout += line;
  });

  child.on('exit', (code, signal) => {
    assert.strictEqual(code, 0);
    assert.strictEqual(signal, null);
    // This bit makes sure that each benchmark file is being sent settings such
    // that the benchmark file runs just one set of options. This helps keep the
    // benchmark tests from taking a long time to run. Therefore, each benchmark
    // file should result in three lines of output: a blank line, a line with
    // the name of the benchmark file, and a line with the only results that we
    // get from testing the benchmark file.
    assert.ok(
      /^(?:\n.+?\n.+?\n)+$/.test(stdout),
      `benchmark file not running exactly one configuration in test: ${stdout}`
    );
  });
}

module.exports = runBenchmark;