Function createSet

test/fixtures/snapshot/typescript.js:1675–1816

* Creates a Set with custom equality and hash code functionality. This is useful when you * want to use something looser than object identity - e.g. "has the same span". * * If `equals(a, b)`, it must be the case that `getHashCode(a) === getHashCode(b)`. * The converse is not re

(getHashCode, equals)

     * assumed not to be an array type.
     */
    function createSet(getHashCode, equals) {
        var multiMap = new ts.Map();
        var size = 0;
        function getElementIterator() {
            var valueIt = multiMap.values();
            var arrayIt;
            return {
                next: function () {
                    while (true) {
                        if (arrayIt) {
                            var n = arrayIt.next();
                            if (!n.done) {
                                return { value: n.value };
                            }
                            arrayIt = undefined;
                        }
                        else {
                            var n = valueIt.next();
                            if (n.done) {
                                return { value: undefined, done: true };
                            }
                            if (!isArray(n.value)) {
                                return { value: n.value };
                            }
                            arrayIt = arrayIterator(n.value);
                        }
                    }
                }
            };
        }
        var set = {
            has: function (element) {
                var hash = getHashCode(element);
                if (!multiMap.has(hash))
                    return false;
                var candidates = multiMap.get(hash);
                if (!isArray(candidates))
                    return equals(candidates, element);
                for (var _i = 0, candidates_1 = candidates; _i < candidates_1.length; _i++) {
                    var candidate = candidates_1[_i];
                    if (equals(candidate, element)) {
                        return true;
                    }
                }
                return false;
            },
            add: function (element) {
                var hash = getHashCode(element);
                if (multiMap.has(hash)) {
                    var values = multiMap.get(hash);
                    if (isArray(values)) {
                        if (!contains(values, element, equals)) {
                            values.push(element);
                            size++;
                        }
                    }
                    else {
                        var value = values;