/** The indexOf() method Returns the position of the first occurrence of a value in a string. The indexOf() method returns -1 if the value is not found. The indexOf() method is case sensitive. */ function isValidPassword(password, username) { if ( password.length < 8 || password.indexOf(' ') !== -1 || password.indexOf(username) !== -1 ) { return false; } return true; } /** or */ function isValidPassword(password, username) { const tooShort = password.length < 8; const hasSpace = password.indexOf(' ') !== -1; const tooSimilar = password.indexOf(username) !== -1; if (tooShort || hasSpace || tooSimilar) return false; return true; }