Count occurrences in a list, and sort output.

gistfile1.txt

// Read the list, and count the names after the @ symbols.

// current-history.txt format:
// @user1 @user2

const fs = require('fs');

const history = {};

const text = fs.readFileSync('current-history.txt', 'utf8');
const lines = text.split('\n');

for (const line of lines) {
  const people = Array.from(line.matchAll(/(@\w+\s*\w*)/g));

  people.forEach(([person]) => {
    history[person] = history[person] ? history[person] + 1 : 1
  });
}

sortedPeople = Object.entries(history).sort((a, b) => {
  return a[1] - b[1];
}).reverse();

const listAsText = sortedPeople.map(person => person.reverse().join(' ')).join('\n');

console.log(listAsText);