"İ".toLowerCase() != "i"
You’ll need a Turkish-specific case conversion, available with String#toLocaleLowerCase:
let s = "İ";
console.log(s.toLowerCase().length);
console.log(s.toLocaleLowerCase('tr-TR').length);You’ll need a Turkish-specific case conversion, available with String#toLocaleLowerCase:
let s = "İ";
console.log(s.toLowerCase().length);
console.log(s.toLocaleLowerCase('tr-TR').length);