How to sort emails array with JavaScript based on given importance object as number

Javascript Sort an array based on importance given as an object

function emailSort(a, b) {
    const importance = {"gmail.com": 1, "yahoo.com": 2, "rocketmail.com": 3, "ymail.com": 4};

    const importanceOfA = importance[a.split('@')[1]];
    const importanceOfB = importance[b.split('@')[1]];

    if (importanceOfA && !importanceOfB) return -1;
    if (importanceOfB && !importanceOfA) return 1;
    if (importanceOfA && importanceOfB) return importanceOfA - importanceOfB;

    return 0;
}

arra = [
    "juni1@rocketmail.com",
    "juni2@rocketmail.com",
    "juni3@rocketmail.com",
    "juni1@yahoo.com",
    "juni2@yahoo.com",
    "juni3@yahoo.com",
    "juni1@ymail.com",
    "juni3@ymail.com",
    "juni2@ymail.com",
    "juni1@gmail.com",
    "junaid4567@gmail.com",
    "juni4@gmail.com",
]
newArray = arra.sort(emailSort);
console.log(newArray)
//will return
// [ 'juni4@gmail.com', 
//   'junaid4567@gmail.com', 
//   'juni1@gmail.com', 
//   'juni1@yahoo.com', 
//   'juni2@yahoo.com', 
//   'juni3@yahoo.com', 
//   'juni2@rocketmail.com', 
//   'juni3@rocketmail.com', 
//   'juni1@rocketmail.com', 
//   'juni2@ymail.com', 
//   'juni3@ymail.com', 
//   'juni1@ymail.com' ]