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// Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.//// Adapted from Node.js. Copyright Joyent, Inc. and other Node contributors.//// Permission is hereby granted, free of charge, to any person obtaining a// copy of this software and associated documentation files (the// "Software"), to deal in the Software without restriction, including// without limitation the rights to use, copy, modify, merge, publish,// distribute, sublicense, and/or sell copies of the Software, and to permit// persons to whom the Software is furnished to do so, subject to the// following conditions://// The above copyright notice and this permission notice shall be included// in all copies or substantial portions of the Software.//// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE// USE OR OTHER DEALINGS IN THE SOFTWARE.import {  assert,  assertEquals,  assertStrictEquals,  assertThrowsAsync,} from "../../testing/asserts.ts";import { promisify } from "./_util_promisify.ts";import * as fs from "../fs.ts";
// deno-lint-ignore no-explicit-anytype VoidFunction = (...args: any[]) => void;
const readFile = promisify(fs.readFile);const customPromisifyArgs = Symbol.for("nodejs.util.promisify.customArgs");
Deno.test(  "Errors should reject the promise",  async function testPromiseRejection() {    await assertThrowsAsync(() => readFile("/dontexist"), Deno.errors.NotFound);  },);
Deno.test("Promisify.custom", async function testPromisifyCustom() {  function fn(): void {}
  function promisifedFn(): void {}  // @ts-expect-error TypeScript (as of 3.7) does not support indexing namespaces by symbol  fn[promisify.custom] = promisifedFn;
  const promisifiedFnA = promisify(fn);  const promisifiedFnB = promisify(promisifiedFnA);  assertStrictEquals(promisifiedFnA, promisifedFn);  assertStrictEquals(promisifiedFnB, promisifedFn);
  await promisifiedFnA;  await promisifiedFnB;});
Deno.test("promiisfy.custom symbol", function testPromisifyCustomSymbol() {  function fn(): void {}
  function promisifiedFn(): void {}
  // util.promisify.custom is a shared symbol which can be accessed  // as `Symbol.for("nodejs.util.promisify.custom")`.  const kCustomPromisifiedSymbol = Symbol.for("nodejs.util.promisify.custom");  // @ts-expect-error TypeScript (as of 3.7) does not support indexing namespaces by symbol  fn[kCustomPromisifiedSymbol] = promisifiedFn;
  assertStrictEquals(kCustomPromisifiedSymbol, promisify.custom);  assertStrictEquals(promisify(fn), promisifiedFn);  assertStrictEquals(promisify(promisify(fn)), promisifiedFn);});
Deno.test("Invalid argument should throw", function testThrowInvalidArgument() {  function fn(): void {}  // @ts-expect-error TypeScript (as of 3.7) does not support indexing namespaces by symbol  fn[promisify.custom] = 42;  try {    promisify(fn);  } catch (e) {    assertStrictEquals(e.code, "ERR_INVALID_ARG_TYPE");    assert(e instanceof TypeError);  }});
Deno.test("Custom promisify args", async function testPromisifyCustomArgs() {  const firstValue = 5;  const secondValue = 17;
  function fn(callback: VoidFunction): void {    callback(null, firstValue, secondValue);  }
  // @ts-expect-error TypeScript (as of 3.7) does not support indexing namespaces by symbol  fn[customPromisifyArgs] = ["first", "second"];
  const obj = await promisify(fn)();  assertEquals(obj, { first: firstValue, second: secondValue });});
Deno.test(  "Multiple callback args without custom promisify args",  async function testPromisifyWithoutCustomArgs() {    function fn(callback: VoidFunction): void {      callback(null, "foo", "bar");    }    const value = await promisify(fn)();    assertStrictEquals(value, "foo");  },);
Deno.test(  "Undefined resolved value",  async function testPromisifyWithUndefinedResolvedValue() {    function fn(callback: VoidFunction): void {      callback(null);    }    const value = await promisify(fn)();    assertStrictEquals(value, undefined);  },);
Deno.test(  "Undefined resolved value II",  async function testPromisifyWithUndefinedResolvedValueII() {    function fn(callback: VoidFunction): void {      callback();    }    const value = await promisify(fn)();    assertStrictEquals(value, undefined);  },);
Deno.test(  "Resolved value: number",  async function testPromisifyWithNumberResolvedValue() {    function fn(err: Error | null, val: number, callback: VoidFunction): void {      callback(err, val);    }    const value = await promisify(fn)(null, 42);    assertStrictEquals(value, 42);  },);
Deno.test(  "Rejected value",  async function testPromisifyWithNumberRejectedValue() {    function fn(err: Error | null, val: null, callback: VoidFunction): void {      callback(err, val);    }    await assertThrowsAsync(      () => promisify(fn)(new Error("oops"), null),      Error,      "oops",    );  },);
Deno.test("Rejected value", async function testPromisifyWithAsObjectMethod() {  const o: { fn?: VoidFunction } = {};  const fn = promisify(function (this: unknown, cb: VoidFunction): void {    cb(null, this === o);  });
  o.fn = fn;
  const val = await o.fn();  assert(val);});
Deno.test(  "Multiple callback",  async function testPromisifyWithMultipleCallback() {    const err = new Error(      "Should not have called the callback with the error.",    );    const stack = err.stack;
    const fn = promisify(function (cb: VoidFunction): void {      cb(null);      cb(err);    });
    await fn();    await Promise.resolve();    return assertStrictEquals(stack, err.stack);  },);
Deno.test("Promisify a promise", function testPromisifyPromise() {  function c(): void {}  const a = promisify(function (): void {});  const b = promisify(a);  assert(c !== a);  assertStrictEquals(a, b);});
Deno.test("Test error", async function testInvalidArguments() {  let errToThrow;
  const thrower = promisify(function (    a: number,    b: number,    c: number,    cb: VoidFunction,  ): void {    errToThrow = new Error(`${a}-${b}-${c}-${cb}`);    throw errToThrow;  });
  try {    await thrower(1, 2, 3);    throw new Error(`should've failed`);  } catch (e) {    assertStrictEquals(e, errToThrow);  }});
Deno.test("Test invalid arguments", function testInvalidArguments() {  [undefined, null, true, 0, "str", {}, [], Symbol()].forEach((input) => {    try {      // @ts-expect-error TypeScript      promisify(input);    } catch (e) {      assertStrictEquals(e.code, "ERR_INVALID_ARG_TYPE");      assert(e instanceof TypeError);      assertEquals(        e.message,        `The "original" argument must be of type Function. Received ${typeof input}`,      );    }  });});