reverse_array_in_pace.js

const reverseArrayInPlace = arr => {
  
  for(let i = 0; i < (arr.length / 2)+1; i++) {
    const first = arr.shift()
    arr.splice(arr.length - i, 0, first)
  }

  return arr
}

const arr = ['a', 'b', 'c', 'd', 'e']
const reversed = reverseArrayInPlace([...arr])

console.log(`reverse of '${arr}' is '${reversed}'`)