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std/collections/max_by_test.ts

Deno standard library
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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
import { assertEquals } from "../testing/asserts.ts";import { maxBy } from "./max_by.ts";
Deno.test("[collections/maxBy] of array of input", () => { const input = [ { name: "Kyle", age: 34 }, { name: "John", age: 42 }, { name: "Anna", age: 23 }, ];
const max = maxBy(input, (i) => i.age);
assertEquals(max, { name: "John", age: 42 });});
Deno.test("[collections/maxBy] of array of input with mutation", () => { const input = [ { name: "Kyle", age: 34 }, { name: "John", age: 42 }, { name: "Anna", age: 23 }, ];
const max = maxBy(input, (i) => i.age - 10);
assertEquals(max, { name: "John", age: 42 });});
Deno.test("[collections/maxBy] of array of input with multiple max", () => { const input = [ { name: "Kyle", age: 34 }, { name: "John", age: 42 }, { name: "John", age: 42 }, { name: "Anna", age: 23 }, ];
const max = maxBy(input, (i) => i.age);
assertEquals(max, { name: "John", age: 42 });});
Deno.test("[collections/maxBy] of array of positive numbers", () => { const input = [2, 3, 5];
const max = maxBy(input, (i) => i);
assertEquals(max, 5);});
Deno.test("[collections/maxBy] of array of negative numbers", () => { const input = [-2, -3, -5];
const max = maxBy(input, (i: number) => i);
assertEquals(max, -2);});
Deno.test("[collections/maxBy] of array of strings", () => { const input = ["Kyle", "John", "Anna"];
const max = maxBy(input, (i: string) => i);
assertEquals(max, "Kyle");});
Deno.test("[collections/maxBy] of empty array", () => { const input: number[] = [];
const max = maxBy(input, (i) => i);
assertEquals(max, undefined);});
Deno.test("[collections/maxBy] of array of numbers with multiple max", () => { const input = [2, 3, 5, 5];
const max = maxBy(input, (i) => i);
assertEquals(max, 5);});
Deno.test("[collections/maxBy] of array of numbers with infinity", () => { const input = [2, 3, 5, Infinity];
const max = maxBy(input, (i) => i);
assertEquals(max, Infinity);});
Deno.test("[collections/maxBy] of array of numbers with NaN", () => { const input = [2, 3, 5, NaN];
const max = maxBy(input, (i) => i);
assertEquals(max, 5);});
Deno.test("[collections/maxBy] no mutation", () => { const input = [2, 3, 5];
maxBy(input, (i) => i);
assertEquals(input, [2, 3, 5]);});
Deno.test("[collections/maxBy] empty input", () => { const emptyArray: Array<{ age: number }> = []; const max = maxBy(emptyArray, (it) => it.age);
assertEquals(max, undefined);});
Deno.test({ name: "[collections/sortBy] bigint", fn() { const input = [ "9007199254740999", "9007199254740991", "9007199254740995", ];
assertEquals(maxBy(input, (it) => BigInt(it)), "9007199254740999"); },});
Deno.test({ name: "[collections/sortBy] date", fn() { const input = [ "February 1, 2022", "December 17, 1995", "June 12, 2012", ];
assertEquals(maxBy(input, (it) => new Date(it)), "February 1, 2022"); },});