// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license. import { assertEquals } from "@std/assert"; import { maxBy } from "./max_by.ts"; Deno.test("maxBy() handles array 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("maxBy() handles array 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("maxBy() handles array 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("maxBy() handles array of positive numbers", () => { const input = [2, 3, 5]; const max = maxBy(input, (i) => i); assertEquals(max, 5); }); Deno.test("maxBy() handles array of negative numbers", () => { const input = [-2, -3, -5]; const max = maxBy(input, (i: number) => i); assertEquals(max, -2); }); Deno.test("maxBy() handles array of strings", () => { const input = ["Kyle", "John", "Anna"]; const max = maxBy(input, (i: string) => i); assertEquals(max, "Kyle"); }); Deno.test("maxBy() handles of empty array", () => { const input: number[] = []; const max = maxBy(input, (i) => i); assertEquals(max, undefined); }); Deno.test("maxBy() handles array of numbers with multiple max", () => { const input = [2, 3, 5, 5]; const max = maxBy(input, (i) => i); assertEquals(max, 5); }); Deno.test("maxBy() handles array of numbers with infinity", () => { const input = [2, 3, 5, Infinity]; const max = maxBy(input, (i) => i); assertEquals(max, Infinity); }); Deno.test("maxBy() handles array of numbers with NaN", () => { const input = [2, 3, 5, NaN]; const max = maxBy(input, (i) => i); assertEquals(max, 5); }); Deno.test("maxBy() handles no mutation", () => { const input = [2, 3, 5]; maxBy(input, (i) => i); assertEquals(input, [2, 3, 5]); }); Deno.test("maxBy() handles empty input", () => { const emptyArray: Array<{ age: number }> = []; const max = maxBy(emptyArray, (it) => it.age); assertEquals(max, undefined); }); Deno.test({ name: "maxBy() handles bigint", fn() { const input = [ "9007199254740999", "9007199254740991", "9007199254740995", ]; assertEquals(maxBy(input, (it) => BigInt(it)), "9007199254740999"); }, }); Deno.test({ name: "maxBy() handles date", fn() { const input = [ "February 1, 2022", "December 17, 1995", "June 12, 2012", ]; assertEquals(maxBy(input, (it) => new Date(it)), "February 1, 2022"); }, });