JSFiddle - React, Tailwind, and code Playground

JavaScript

var data = [{
  number: 1,
  text: 123
}, {
  number: 1,
  text: 321
}, {
  number: 2,
  text: 888
}, {
  number: 3,
  text: 000
}];

var result = [{
  number: 1,
  messages: [{
    text: 123
  }, {
    text: 321
  }]
}, {
  number: 2,
  messages: [{
    text: 888
  }]
}, {
  number: 3,
  messages: [{
    text: 000
  }]
}]