How do I create an array of date intervals from an array of dates in Javascript?

Question

From an array:

["01/01/2015", "02/01/2015", "03/01/2015", "05/01/2015", "06/01/2015"]; 

to

[{start_date: "01/01/2015", end_date: "03/01/2015"}, { start_date: "05/05/2015", end_date: "06/01/2015 }]; 

Is there a library available for this type of functions?

I would like to convert the first array dates to an array of objects that represent time intervals.

PS: date format in the question is dd-MM-yyyy

Answer 1

const strings = ["01/01/2015", "02/01/2015", "03/01/2015", "05/01/2015", "06/01/2015"];

const dates = strings.map(str => ({
  date: new Date(str.split(/\//g).reverse().join('-') + 'T00:00:00Z'),
  string: str
}))

let current = { start_date: dates[0].string }

const intervals = [current]

for (let i = 1; i < dates.length; i += 1) {
  const diff = (dates[i].date - dates[i - 1].date) / (1000 * 60 * 60 * 24)
  if (diff === 1) {
    current.end_date = dates[i].string
  } else {
    current = { start_date: dates[i].string }
    intervals.push(current)
  }
}

console.log(intervals)