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// deno-fmt-ignore-file// deno-lint-ignore-file
// Copyright Joyent and Node contributors. All rights reserved. MIT license.// Taken from Node 18.12.0// This file is automatically generated by "node/_tools/setup.ts". Do not modify this file manually
'use strict';
const common = require('../common');
// Ensure that subscribing the 'data' event will not make the stream flow.// The 'data' event will require calling read() by hand.//// The test is written for the (somewhat rare) highWaterMark: 0 streams to// specifically catch any regressions that might occur with these streams.
const assert = require('assert');const { Readable } = require('stream');
const streamData = [ 'a', null ];
// Track the calls so we can assert their order later.const calls = [];const r = new Readable({  read: common.mustCall(() => {    calls.push('_read:' + streamData[0]);    process.nextTick(() => {      calls.push('push:' + streamData[0]);      r.push(streamData.shift());    });  }, streamData.length),  highWaterMark: 0,
  // Object mode is used here just for testing convenience. It really  // shouldn't affect the order of events. Just the data and its format.  objectMode: true,});
assert.strictEqual(r.readableFlowing, null);r.on('readable', common.mustCall(() => {  calls.push('readable');}, 2));assert.strictEqual(r.readableFlowing, false);r.on('data', common.mustCall((data) => {  calls.push('data:' + data);}, 1));r.on('end', common.mustCall(() => {  calls.push('end');}));assert.strictEqual(r.readableFlowing, false);
// The stream emits the events asynchronously but that's not guaranteed to// happen on the next tick (especially since the _read implementation above// uses process.nextTick).//// We use setImmediate here to give the stream enough time to emit all the// events it's about to emit.setImmediate(() => {
  // Only the _read, push, readable calls have happened. No data must be  // emitted yet.  assert.deepStrictEqual(calls, ['_read:a', 'push:a', 'readable']);
  // Calling 'r.read()' should trigger the data event.  assert.strictEqual(r.read(), 'a');  assert.deepStrictEqual(    calls,    ['_read:a', 'push:a', 'readable', 'data:a']);
  // The next 'read()' will return null because hwm: 0 does not buffer any  // data and the _read implementation above does the push() asynchronously.  //  // Note: This 'null' signals "no data available". It isn't the end-of-stream  // null value as the stream doesn't know yet that it is about to reach the  // end.  //  // Using setImmediate again to give the stream enough time to emit all the  // events it wants to emit.  assert.strictEqual(r.read(), null);  setImmediate(() => {
    // There's a new 'readable' event after the data has been pushed.    // The 'end' event will be emitted only after a 'read()'.    //    // This is somewhat special for the case where the '_read' implementation    // calls 'push' asynchronously. If 'push' was synchronous, the 'end' event    // would be emitted here _before_ we call read().    assert.deepStrictEqual(      calls,      ['_read:a', 'push:a', 'readable', 'data:a',       '_read:null', 'push:null', 'readable']);
    assert.strictEqual(r.read(), null);
    // While it isn't really specified whether the 'end' event should happen    // synchronously with read() or not, we'll assert the current behavior    // ('end' event happening on the next tick after read()) so any changes    // to it are noted and acknowledged in the future.    assert.deepStrictEqual(      calls,      ['_read:a', 'push:a', 'readable', 'data:a',       '_read:null', 'push:null', 'readable']);    process.nextTick(() => {      assert.deepStrictEqual(        calls,        ['_read:a', 'push:a', 'readable', 'data:a',         '_read:null', 'push:null', 'readable', 'end']);    });  });});