function hookErr (_, errSuite, after) {
    // before/after Each hook for errSuite failed:
    var orig = self.suite;

    // for failed 'after each' hook start from errSuite parent,
    // otherwise start from errSuite itself
    self.suite = after ? errSuite.parent : errSuite;

    if (self.suite) {
      // call hookUp afterEach
      self.hookUp('afterEach', function (err2, errSuite2) {
        self.suite = orig;
        // some hooks may fail even now
        if (err2) {
          return hookErr(err2, errSuite2, true);
        }
        // report error suite
        fn(errSuite);
      });
    } else {
      // there is no need calling other 'after each' hooks
      self.suite = orig;
      fn(errSuite);
    }
  }
Run tests in the given `suite` and invoke the callback `fn()` when complete.

@api private
@param {Suite} suite
@param {Function} fn