code: function AssertionError(rule, result, stackStartFn) {
      return new assert.AssertionError({
          message: `benchmark "${result.name}": actual:${result.average}msec/op ${rule.operator} expected:${rule.expected}msec/op`,
          actual: `${result.average} msec/op`,
          expected: `${rule.expected} msec/op`,
          operator: rule.operator,
          stackStartFn: stackStartFn || rule.assert,
      });
  }
docs: Generate {@link AssertionError}
  
  @param {AssertRule} rule - the rule that couses error.
  @param {Result} result - the result for assert.
  @param {function} [stackStartFn] - provided function will remove from stack trace.
  
  @return {assert.AssertionError} generated error
  
  @ignore
  @since 0.3.0