// deno-fmt-ignore-file // deno-lint-ignore-file // Copyright Joyent and Node contributors. All rights reserved. MIT license. // Taken from Node 20.11.1 // This file is automatically generated by `tests/node_compat/runner/setup.ts`. Do not modify this file manually. 'use strict'; const common = require('../common'); const fixtures = require('../common/fixtures'); const { Readable, } = require('stream'); const assert = require('assert'); const { setTimeout } = require('timers/promises'); const { createReadStream } = require('fs'); function oneTo5() { return Readable.from([1, 2, 3, 4, 5]); } { // flatMap works on synchronous streams with a synchronous mapper (async () => { assert.deepStrictEqual( await oneTo5().flatMap((x) => [x + x]).toArray(), [2, 4, 6, 8, 10] ); assert.deepStrictEqual( await oneTo5().flatMap(() => []).toArray(), [] ); assert.deepStrictEqual( await oneTo5().flatMap((x) => [x, x]).toArray(), [1, 1, 2, 2, 3, 3, 4, 4, 5, 5] ); })().then(common.mustCall()); } { // flatMap works on sync/async streams with an asynchronous mapper (async () => { assert.deepStrictEqual( await oneTo5().flatMap(async (x) => [x, x]).toArray(), [1, 1, 2, 2, 3, 3, 4, 4, 5, 5] ); const asyncOneTo5 = oneTo5().map(async (x) => x); assert.deepStrictEqual( await asyncOneTo5.flatMap(async (x) => [x, x]).toArray(), [1, 1, 2, 2, 3, 3, 4, 4, 5, 5] ); })().then(common.mustCall()); } { // flatMap works on a stream where mapping returns a stream (async () => { const result = await oneTo5().flatMap(async (x) => { return Readable.from([x, x]); }).toArray(); assert.deepStrictEqual(result, [1, 1, 2, 2, 3, 3, 4, 4, 5, 5]); })().then(common.mustCall()); // flatMap works on an objectMode stream where mappign returns a stream (async () => { const result = await oneTo5().flatMap(() => { return createReadStream(fixtures.path('x.txt')); }).toArray(); // The resultant stream is in object mode so toArray shouldn't flatten assert.strictEqual(result.length, 5); assert.deepStrictEqual( Buffer.concat(result).toString(), 'xyz\n'.repeat(5) ); })().then(common.mustCall()); } { // Concurrency + AbortSignal const ac = new AbortController(); const stream = oneTo5().flatMap(common.mustNotCall(async (_, { signal }) => { await setTimeout(100, { signal }); }), { signal: ac.signal, concurrency: 2 }); // pump assert.rejects(async () => { for await (const item of stream) { // nope console.log(item); } }, { name: 'AbortError', }).then(common.mustCall()); queueMicrotask(() => { ac.abort(); }); } { // Already aborted AbortSignal const stream = oneTo5().flatMap(common.mustNotCall(async (_, { signal }) => { await setTimeout(100, { signal }); }), { signal: AbortSignal.abort() }); // pump assert.rejects(async () => { for await (const item of stream) { // nope console.log(item); } }, { name: 'AbortError', }).then(common.mustCall()); } { // Error cases assert.throws(() => Readable.from([1]).flatMap(1), /ERR_INVALID_ARG_TYPE/); assert.throws(() => Readable.from([1]).flatMap((x) => x, { concurrency: 'Foo' }), /ERR_OUT_OF_RANGE/); assert.throws(() => Readable.from([1]).flatMap((x) => x, 1), /ERR_INVALID_ARG_TYPE/); assert.throws(() => Readable.from([1]).flatMap((x) => x, { signal: true }), /ERR_INVALID_ARG_TYPE/); } { // Test result is a Readable const stream = oneTo5().flatMap((x) => x); assert.strictEqual(stream.readable, true); } { const stream = oneTo5(); Object.defineProperty(stream, 'map', { value: common.mustNotCall(), }); // Check that map isn't getting called. stream.flatMap(() => true); }