1️⃣ Explain here what's wrong

function getNames() {
  return ['foo', 'bar', 'foo'];
}

const uniqueNames = [...new Set(...getNames())]; // I mistakenly spreading the `getNames()`
console.log(uniqueNames) // Print [ 'f', 'o' ]. But what I expect is ['foo', 'bar']

no-useless-spread should report error on the code new Set(...getNames()). But actually not.

Because new Set() accept one or zero parameter, we don't need to spread the parameters.

Example

const foo = ['abc'];
const set = new Set(...foo); // BAD!
const set = new Set(foo[0]); // OK

2️⃣ Specify which rule is buggy here and in the title
no-useless-spread

3️⃣ More information
TypeScript should report error when compiling the code above. Unfortunately, this problem havn't been fixed yet. Set microsoft/TypeScript#59390 and microsoft/TypeScript#48575