flatten.js

const test = require("tape");
const { flatten } = require("../");
const {
  infiniteIterableOfPositiveIntegers,
  testAndToArray,
  oneTwoThree,
  oneTwoThreeFour,
  positiveIntegers,
  takeEight,
  threeTwoOne,
} = require("./_tools");

test("flatten", (t) => {
  const processIterable = testAndToArray(t);
  t.deepEqual(
    processIterable(flatten([oneTwoThree, threeTwoOne, oneTwoThreeFour])),
    [...oneTwoThree, ...threeTwoOne, ...oneTwoThreeFour],
  );
  t.deepEqual(
    processIterable(flatten([1, oneTwoThree, threeTwoOne, oneTwoThreeFour])),
    [1, ...oneTwoThree, ...threeTwoOne, ...oneTwoThreeFour],
  );
  t.deepEqual(
    processIterable(
      flatten([1, [[[[oneTwoThree]]]], threeTwoOne, oneTwoThreeFour]),
    ),
    [1, ...oneTwoThree, ...threeTwoOne, ...oneTwoThreeFour],
  );
  t.deepEqual(
    processIterable(takeEight(flatten([oneTwoThree, positiveIntegers]))),
    [...oneTwoThree, ...oneTwoThreeFour, 5],
  );
  t.deepEqual(
    processIterable(takeEight(flatten(infiniteIterableOfPositiveIntegers))),
    [1, 2, 3, 4, 5, 6, 7, 8],
  );
  t.end();
});