code: function suite() {
    process.env.NODESASS_COV = 1;
  
    var coveralls = spawn(bin('coveralls'));
  
    var args = [bin('_mocha')].concat(['--reporter', 'mocha-lcov-reporter']);
    var mocha = spawn(process.sass.runtime.execPath, args, {
      env: process.env
    });
  
    mocha.on('error', function(err) {
      console.error(err);
      process.exit(1);
    });
  
    mocha.stderr.setEncoding('utf8');
    mocha.stderr.on('data', function(err) {
      console.error(err);
      process.exit(1);
    });
  
    mocha.stdout.pipe(coveralls.stdin);
  }
docs: Run test suite
  
  @api private