Regex: remove underscore - add spaces before uppercase - remove double spaces - remove duplicate words

someUsefulRegexStr.js

let str = "Hello__helloWorld__minor"

str = str.replace(/_/g, ' ').trim() // remove underscore
str = str.replace(/([A-Z])/g, ' $1') // add spaces before uppercase
str = str.replace(/  +/g, ' '); // remove double space
str = str.replace(/(\b\S+\b)(?=.*\1)/ig, '') // remove duplicate words https://stackoverflow.com/a/46364625

console.log(str.trim())