function Spec (runner) {
  Base.call(this, runner);

  var self = this;
  var indents = 0;
  var n = 0;

  function indent () {
    return Array(indents).join('  ');
  }

  runner.on('start', function () {
    console.log();
  });

  runner.on('suite', function (suite) {
    ++indents;
    console.log(color('suite', '%s%s'), indent(), suite.title);
  });

  runner.on('suite end', function () {
    --indents;
    if (indents === 1) {
      console.log();
    }
  });

  runner.on('pending', function (test) {
    var fmt = indent() + color('pending', '  - %s');
    console.log(fmt, test.title);
  });

  runner.on('pass', function (test) {
    var fmt;
    if (test.speed === 'fast') {
      fmt = indent() +
        color('checkmark', '  ' + Base.symbols.ok) +
        color('pass', ' %s');
      console.log(fmt, test.title);
    } else {
      fmt = indent() +
        color('checkmark', '  ' + Base.symbols.ok) +
        color('pass', ' %s') +
        color(test.speed, ' (%dms)');
      console.log(fmt, test.title, test.duration);
    }
  });

  runner.on('fail', function (test) {
    console.log(indent() + color('fail', '  %d) %s'), ++n, test.title);
  });

  runner.on('end', self.epilogue.bind(self));
}
Initialize a new `Spec` test reporter.

@api public
@param {Runner} runner