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import { Lazy } from '../lib/mod.ts';import {  assertEquals,  assertStrictEquals,  assertThrows,} from './deps/std/testing/asserts.ts';
const test = Deno.test;
test('empty', () => {  assertEquals(Lazy.empty().toArray(), []);});
test('from', () => {  const orig = [1, 2, 3, 4, 5];  assertEquals(Lazy.from(orig).toArray(), orig);
  const first = Lazy.from(orig);  assertStrictEquals(Lazy.from(first), first);
  const second = first.where(i => i % 2 === 0);  assertStrictEquals(Lazy.from(second), second);
  const third = second.select(i => i ** 2);  assertStrictEquals(Lazy.from(third), third);});
test('range', () => {  assertEquals(Lazy.range(0, 5).toArray(), [0, 1, 2, 3, 4]);  assertEquals(Lazy.range(0, 0).toArray(), []);  assertEquals(Lazy.range(0, 1).toArray(), [0]);  assertEquals(Lazy.range(1, 0).toArray(), [1]);  assertEquals(Lazy.range(5, 0).toArray(), [5, 4, 3, 2, 1]);
  assertEquals(Lazy.range(-1).take(5).toArray(), [-1, 0, 1, 2, 3]);  assertEquals(Lazy.range(0).take(5).toArray(), [0, 1, 2, 3, 4]);  assertEquals(Lazy.range(1).take(5).toArray(), [1, 2, 3, 4, 5]);  assertEquals(Lazy.range(2).take(5).toArray(), [2, 3, 4, 5, 6]);  assertEquals(Lazy.range(3).take(5).toArray(), [3, 4, 5, 6, 7]);  assertEquals(Lazy.range(4).take(5).toArray(), [4, 5, 6, 7, 8]);});
test('repeat', () => {  assertEquals(Lazy.repeat('a', 1).toArray(), ['a']);  assertEquals(Lazy.repeat('a', 2).toArray(), ['a', 'a']);  assertEquals(Lazy.repeat('a', 3).toArray(), ['a', 'a', 'a']);  assertEquals(Lazy.repeat('a', 4).toArray(), ['a', 'a', 'a', 'a']);  assertEquals(Lazy.repeat('a', 5).toArray(), ['a', 'a', 'a', 'a', 'a']);  assertThrows(() => Lazy.repeat('a', -1));
  assertEquals(Lazy.repeat('a').take(1).toArray(), ['a']);  assertEquals(Lazy.repeat('a').take(2).toArray(), ['a', 'a']);  assertEquals(Lazy.repeat('a').take(3).toArray(), ['a', 'a', 'a']);  assertEquals(Lazy.repeat('a').take(4).toArray(), ['a', 'a', 'a', 'a']);  assertEquals(Lazy.repeat('a').take(5).toArray(), ['a', 'a', 'a', 'a', 'a']);});
test('_forAwait', async () => {  // This isn't a test of any specific implementation, just of functionality.
  const orig = [    Promise.resolve(1),    Promise.resolve(2),    Promise.resolve(3),    Promise.resolve(4),    Promise.resolve(5),  ];
  let current = 1;  for await (const element of Lazy.from(orig)) {    assertEquals(element, current);    current++;  }});