Javascript Calc - Won't pass US#14

Hello! My calculator seems to be working but isn’t passing the following:

Link to Calculator

  • User Story #14: Pressing an operator immediately following = should start a new calculation that operates on the result of the previous evaluation.

Would really appreciate any assistance figuring out why. I am using React and Redux.

Calculator Component

class Calculator extends Component {
    // Adding click event handler to all button divs, once component has rendered
    componentDidMount() {
      [...document.querySelectorAll('.operand, .operator, .equals, .clear')]
        .forEach(btn => btn.addEventListener('click', this.handleClick.bind(this)));
    // Passes clicked btn to action creator
    handleClick(event) {
    // CSS grid for layout, Display for result is taken off state
    render() {
        return (
            <h4>React-Redux Calculator</h4>
            <div className='wrapper'>
                <div id='display'>{this.props.result}</div>
                <div className='clear' id='clear'><button>AC</button></div>
                <div className='operator' id='divide'><button>/</button></div>
                ... more button divs
            <p>Coded by <a href=''>Ricardo Ledesma</a></p>

const mapStateToProps = ({ result }) => ({ result });
const mapDispatchToProps = dispath => bindActionCreators({ btnClick }, dispath); 
export default connect(mapStateToProps, mapDispatchToProps)(Calculator);

root reducer

const rootReducer = combineReducers({
  result: resultReducer,

export default rootReducer;

result_reducer - relevant cases

const endsWithOperator = /[*/+-]$/;
const digitsOperatordigits = /^\d+[*/+-]\d+$/;
const onlyOperator = /^[*/+-]$/;

export default function (state = '0', action) {
  switch (action.type) {
    case EQUALS_CLICK:
      if (/\d[*/+-]\d/.test(state)) { return parseFloat(eval(state).toFixed(4)); }
      return state;

      if (state.length > 15) { return state; }
      else if (onlyOperator.test(state) && /[/*]/.test(action.payload)) {
        return state;
      } else if (endsWithOperator.test(state)) {
        return `${state.slice(0, -1)}${action.payload}`;
      } else if (digitsOperatordigits.test(state)) { 
        return `${state}${action.payload}`;
      } else if (state === '0') { 
        if (/[-+]/.test(action.payload)) { return action.payload; }
        return state;
      return `${state}${action.payload}`;

I’m handling the equals case first, It returns the result and then state is – the result. Any further calculations are done on the result unless AC is clicked. It’s working but not passing tests.

Please help!


First issue is becasue you set the id equals to parent of related button. You may need to allocate the key id to the button, not the container.

The same story about dot key.

I think if you fix this issue, and remove all key ids from their parent and associate them to buttons could pass the test.

1 Like

It passes! Thanks so much!