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// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
import { assertEquals } from "../assert/mod.ts";import { mapKeys } from "./map_keys.ts";
function mapKeysTest<T>(  input: [Record<string, T>, (key: string) => string],  expected: Record<string, T>,  message?: string,) {  const actual = mapKeys(...input);  assertEquals(actual, expected, message);}
Deno.test({  name: "mapKeys() handles no mutation",  fn() {    const object = { a: 5, b: true };    mapKeys(object, (it) => `${it}a`);
    assertEquals(object, { a: 5, b: true });  },});
Deno.test({  name: "mapKeys() handles empty input",  fn() {    mapKeysTest(      [{}, (it) => it],      {},    );  },});
Deno.test({  name: "mapKeys() handles identity",  fn() {    mapKeysTest(      [        {          foo: true,          bar: "lorem",          1: -5,        },        (it) => it,      ],      {        foo: true,        bar: "lorem",        1: -5,      },    );  },});
Deno.test({  name: "mapKeys() handles to constant key",  fn() {    mapKeysTest(      [        { test: "foo", "": [] },        () => "a",      ],      { a: [] },    );  },});
Deno.test({  name: "mapKeys() handles overlapping keys",  fn() {    mapKeysTest(      [        {          "Anna": 22,          "Kim": 24,          "Karen": 33,          "Claudio": 11,          "Karl": 45,        },        (name) => name.charAt(0),      ],      {        "A": 22,        "K": 45,        "C": 11,      },    );    mapKeysTest(      [        {          "ad04": "foo",          "ad28": "bar",          "100f": "dino",        },        (it) => it.slice(0, 2),      ],      {        "ad": "bar",        "10": "dino",      },    );  },});
Deno.test({  name: "mapKeys() handles empty key",  fn() {    mapKeysTest(      [        {          "ab": 22,          "a": 24,          "bcd": 33,          "d": 11,        },        (key) => key.slice(1),      ],      {        "b": 22,        "": 11,        "cd": 33,      },    );  },});
Deno.test({  name: "mapKeys() handles normal mappers",  fn() {    mapKeysTest(      [        {          "/home/deno/food.txt": "Plants, preferably fruit",          "/home/deno/other-dinos.txt": "Noderaptor, Pythonoctorus",        },        (path) => (path.split("/").slice(-1) as [string])[0],      ],      {        "food.txt": "Plants, preferably fruit",        "other-dinos.txt": "Noderaptor, Pythonoctorus",      },    );    mapKeysTest(      [        {          "EUR": 1200,          "USD": 1417,          "JPY": 1563,        },        (currencyCode) =>          ({ EUR: "Euro", USD: "US Dollar", JPY: "Japanese Yen" })[            currencyCode          ] ?? "_",      ],      {        "Euro": 1200,        "US Dollar": 1417,        "Japanese Yen": 1563,      },    );  },});