Today I had to output a tree like object structure in JavaScript. Initially, I came up with this code:

// for spacing
const tab = ( num ) => {
  let tab = "  "
  if ( num === 0 ) {
    return ''
  }
  for (let i=1; i < num; i++) {
    tab += tab
  }
  return tab
} 
// displaying
const display_directory = ( node, depth = 0 ) => {
  for ( let n in node ) {
    console.log(`${tab(depth)}${in}`)
    if ( Object.keys( node[ in ] ).length > 0 ) {
      display_directory( node[ in ], depth+1 )
    }
  }
}

It works perfectly fine, but the issue is that the order of names is going to be random as Object is not sorted. After some moments, I came up with a very simple solution to display name in alphabetical order.

const display_directory = ( node, depth = 0 ) => {
  let keys = Object.keys(node).sort()
  for ( let key of keys ) {
    console.log(`${tab(depth)}${key}`)
    if ( Object.keys( node[ key ] ).length > 0 ) {
      display_directory( node[ key ], depth+1 )
    }
  }
}