Роман Андреевич,
let this.searchList = [];
checkMatches(data) {
if (this.searchList.length === 0 || data === null) {
this.searchList.push(data);
} else {
this.searchList.every((item) => {
if (item === null) return true;
if (item.id !== data.id) return true;
}) && this.searchList.push(data);
}
}