reduce method inside a for loop - JS

Question

I am trying to loop through array of entries using a for loop and use the reduce method, but the reduce returns after the first entry, never getting to the second, third, etc entries to push the result to an array v.

Any thoughts?

export const groupEventData = eventData => {
    console.log(eventData)
    // returns[{
    //     "id": "141",
    //     "name": "00333",
    //     "no_transmission": true,
    //     "low_battery" :true,
    // },
    // {
    //     "id": "307",
    //     "name": "01163",
    //     "no_transmission": true,
    //     "low_data_rate": true,
    // }
    // ]

    // now let's group similar event types
    let v = [];
    let types = ["no_transmission", "low_data_rate", "low_battery"]; 
    for (let x = 0; x <= types.length; x++) {
        let data = eventData.reduce((acc, i) => {
            if (!acc[i[types[x]]] && typeof i[types[x]] !== 'undefined') {
                acc[i[types[x]]] = [i]
            }
            else if (Array.isArray(acc[i[types[x]]])) {
                acc[i[types[x]]].push(i);
            }
            else if (typeof acc[i[types[x]]] === 'object') {
                acc[i[types[x]]] = [acc[i[types[x]]]]
                acc[i[types[x]]].push(i)
            }
            return acc;
        }, {});
        // Doesn't add a property for the type if there are no data
        Object.keys(data).length && v.push({ [types[x]: data });
        return v;
    };

}

Answer 1

You have return v inside your for loop. Try bumping it below the curly brace immediately beneath it. Right now the for loop is iterating only once and then returning a value.

Worked for me below:

const eventData = [
  {"id": "141","name": "00333","no_transmission": true,"low_battery": true},
  {"id": "307","name": "01163","no_transmission": true,"low_data_rate": true}
]

const type = 'bc'

const types = ["no_transmission", "low_data_rate", "low_battery"]

const groupEventData = (eventData, type) => {
  let v = [];
  for (let x = 0; x <= types.length; x++) {
    let data = eventData.reduce((acc, i) => {
      if (!acc[i[types[x]]] && typeof i[types[x]] !== 'undefined') {
        acc[i[types[x]]] = [i]
      }
      else if (Array.isArray(acc[i[types[x]]])) {
        acc[i[types[x]]].push(i);
      }
      else if (typeof acc[i[types[x]]] === 'object') {
        acc[i[types[x]]] = [acc[i[types[x]]]]
        acc[i[types[x]]].push(i)
      }
      return acc;
    }, {});
    Object.keys(data).length && v.push({ [`${types[x]}_${type}`]: data });
  };
  return v;
}

console.log('groupEventData', groupEventData(eventData, type))