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// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
import { assertEquals } from "../assert/mod.ts";import { runningReduce } from "./running_reduce.ts";
Deno.test({  name: "runningReduce() handles no mutation",  fn() {    const numbers = [1, 2, 3, 4, 5];    runningReduce(numbers, (sum, current) => sum + current, 0);
    assertEquals(numbers, [1, 2, 3, 4, 5]);  },});
Deno.test({  name: "runningReduce() handles array of numbers initial value 0",  fn() {    const numbers = [1, 2, 3, 4, 5];    const result = runningReduce(numbers, (sum, current) => sum + current, 0);
    assertEquals(result, [1, 3, 6, 10, 15]);  },});
Deno.test({  name: "runningReduce() handles array of numbers initial value 5",  fn() {    const numbers = [1, 2, 3, 4, 5];    const result = runningReduce(numbers, (sum, current) => sum + current, 5);
    assertEquals(result, [6, 8, 11, 15, 20]);  },});
Deno.test({  name: `runningReduce() handles array of strings initial value ""`,  fn() {    const strings = ["a", "b", "c", "d", "e"];    const result = runningReduce(strings, (str, current) => str + current, "");
    assertEquals(result, ["a", "ab", "abc", "abcd", "abcde"]);  },});
Deno.test({  name: `runningReduce() handles array of strings initial value "foo"`,  fn() {    const strings = ["a", "b", "c", "d", "e"];    const result = runningReduce(      strings,      (str, current) => str + current,      "foo",    );
    assertEquals(result, ["fooa", "fooab", "fooabc", "fooabcd", "fooabcde"]);  },});
Deno.test({  name: "runningReduce() handles empty array initial value 0",  fn() {    const result = runningReduce([], (sum, current) => sum + current, 0);
    assertEquals(result, []);  },});
Deno.test({  name: "runningReduce() handles empty array initial value 5",  fn() {    const result = runningReduce([], (sum, current) => sum + current, 5);
    assertEquals(result, []);  },});
Deno.test({  name: "runningReduce() handles array of objects initial value 0",  fn() {    const medals = [      { country: "USA", count: 113 },      { country: "CHN", count: 88 },      { country: "JPN", count: 58 },    ];    const result = runningReduce(      medals,      (sum, current) => sum + current.count,      0,    );
    assertEquals(result, [113, 201, 259]);  },});
Deno.test({  name: `runningReduce() handles array of objects initial value ""`,  fn() {    const medals = [      { country: "USA", count: 113 },      { country: "CHN", count: 88 },      { country: "JPN", count: 58 },    ];    const result = runningReduce(      medals,      (sum, current) => sum + current.count,      "",    );
    assertEquals(result, ["113", "11388", "1138858"]);  },});
Deno.test({  name: "runningReduce() reduces array of numbers with currentIndex",  fn() {    const numbers = [1, 2, 3, 4, 5];    const result = runningReduce(      numbers,      (sum, current, currentIndex) => sum + current + currentIndex,      0,    );
    assertEquals(result, [1, 4, 9, 16, 25]);  },});
Deno.test({  name: "runningReduce() reduces array of strings with currentIndex",  fn() {    const strings = ["a", "b", "c", "d", "e"];    const result = runningReduce(      strings,      (sum, current, currentIndex) => sum + current + currentIndex,      "",    );
    assertEquals(result, ["a0", "a0b1", "a0b1c2", "a0b1c2d3", "a0b1c2d3e4"]);  },});
Deno.test({  name: "runningReduce() reduces array of objects with currentIndex",  fn() {    const medals = [      { country: "USA", count: 113 },      { country: "CHN", count: 88 },      { country: "JPN", count: 58 },    ];    const result = runningReduce(      medals,      (_, current, currentIndex) => {        return currentIndex + current.country;      },      "",    );
    assertEquals(result, ["0USA", "1CHN", "2JPN"]);  },});