Run results for: Set difference vs set difference with union

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:109.0) Gecko/20100101 Firefox/110.0

Browser: Firefox 110

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
difference(from, [a, b, c]) - match	7646453.5 Ops/sec
difference(from, [a, b, c]) - mismatch	7690365.0 Ops/sec
difference(from, [union(a, b, c)]) - match	1038718.5 Ops/sec
difference(from, [union(a, b, c)]) - mismatch	1114121.5 Ops/sec

Script Preparation code:

var from = new Set();
var match1 = new Set();
var match2 = new Set();
var match3 = new Set();
var mismatch1 = new Set();
var mismatch2 = new Set();
var mismatch3 = new Set();

for (let i = 0; i < 1000; i++) {
    from.add(i);
    match1.add(i);
    match2.add(i);
    match3.add(i);
    mismatch1.add(1000 + i);
    mismatch2.add(2000 + i);
    mismatch3.add(3000 + i);
}

function setsUnion(sets) {
    if (sets.length === 1) {
        return sets[0];
    }

    const result = new Set();
    for (let i = 0; i < sets.length; i++) {
        for (const value of sets[i]) {
            result.add(value);
        }
    }

    return result;
};

function setsDifferenceModify(from, sets) {
    for (const value of from) {
        for (let i = 0; i < sets.length; i++) {
            if (sets[i].has(value)) {
                from.delete(value);
                break;
            }
        }
    }
}

Tests:

difference(from, [a, b, c]) - match
setsDifferenceModify(from, [match1, match2, match3]);
difference(from, [a, b, c]) - mismatch
setsDifferenceModify(from, [mismatch1, mismatch2, mismatch3]);
difference(from, [union(a, b, c)]) - match
setsDifferenceModify(from, [setsUnion(match1, match2, match3)]);
difference(from, [union(a, b, c)]) - mismatch
setsDifferenceModify(from, [setsUnion(mismatch1, mismatch2, mismatch3)]);

Run results for: Set difference vs set difference with union

difference(from, [a, b, c]) - match

difference(from, [a, b, c]) - mismatch

difference(from, [union(a, b, c)]) - match

difference(from, [union(a, b, c)]) - mismatch