geninq/src/functions/union.test.ts

A JavaScript version of the Linq library for Generators

import "./union";
import "./array";
import { It } from "../test-utils";

It(
  "Only includes an element once",
  (s) => s.union([1, 2, 4]).array(),
  [1, 2, 3, 4]
);
It(
  "Only includes an element once from a single sequence",
  (s) => s.union([1, 2, 4, 4]).array(),
  [1, 2, 3, 4]
);

It(
  "Uses a custom comparitor",
  (s) =>
    s
      .union(
        [{ test: 1 }, { test: 2 }, { test: 4 }],
        (a, b) => a.test === b.test
      )
      .array(),
  [{ test: 1 }, { test: 2 }, { test: 3 }, { test: 4 }],
  [{ test: 1 }, { test: 2 }, { test: 3 }]
);