Conditional Parameter addition to an Object Javascript

Question

Following is my code, in which I am trying to add passStatus to an object only if it has a value otherwise omit it.

I tried this one - In Javascript, how to conditionally add a member to an object?

But seems like I am doing it wrong. Any pointers Please.

Code -

var a = {
  firstName: "Tom",
  lastName: "Simmon",
  email: "[email protected]",
  phone: "+36456",
  passStatus: "",
  query: "simple"
};

// var newObj = Object.assign(a, a.passStatus ? {a.passStatus} : null);

var newObj = {
   ...(a.passStatus? {passStatus: a.passStatus}: {} )
}

console.log(newObj); // {} <- Getting a blank object

Expected Output -

If passStatus = ""

{
  firstName: "Tom",
  lastName: "Simmon",
  email: "[email protected]",
  phone: "+36456",
  query: "simple"
}

If passStatus = "pass"

{
  firstName: "Tom",
  lastName: "Simmon",
  email: "[email protected]",
  phone: "+36456",
  passStatus: "pass",
  query: "simple"
}

Answer 1

I think the clearest way to conditionally remove a property from the object like this would be to use rest syntax followed by a possible Object.assign:

var a = {
  firstName: "Tom",
  lastName: "Simmon",
  email: "[email protected]",
  phone: "+36456",
  passStatus: "",
  query: "simple"
};

const { passStatus, ...newObj } = a;
if (passStatus) {
  Object.assign(newObj, { passStatus });
}

console.log(newObj);

You can do it in one line by destructuring a computed property name, where the property name uses the conditional operator to remove the passStatus property if it exists - but this is hard to understand, I wouldn't recommend it:

var a = {
  firstName: "Tom",
  lastName: "Simmon",
  email: "[email protected]",
  phone: "+36456",
  passStatus: "",
  query: "simple"
};

const { [a.passStatus ? '' : 'passStatus']: _, ...newObj } = a;
console.log(newObj);