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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
// 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.
'use strict';require('../common');const assert = require('assert');
const stream = require('stream');const Readable = stream.Readable;const Writable = stream.Writable;
const totalChunks = 100;const chunkSize = 99;const expectTotalData = totalChunks * chunkSize;let expectEndingData = expectTotalData;
const r = new Readable({ highWaterMark: 1000 });let chunks = totalChunks;r._read = function(n) {  console.log('_read called', chunks);  if (!(chunks % 2))    setImmediate(push);  else if (!(chunks % 3))    process.nextTick(push);  else    push();};
let totalPushed = 0;function push() {  const chunk = chunks-- > 0 ? Buffer.alloc(chunkSize, 'x') : null;  if (chunk) {    totalPushed += chunk.length;  }  console.log('chunks', chunks);  r.push(chunk);}
read100();
// First we read 100 bytes.function read100() {  readn(100, onData);}
function readn(n, then) {  console.error(`read ${n}`);  expectEndingData -= n;  (function read() {    const c = r.read(n);    console.error('c', c);    if (!c)      r.once('readable', read);    else {      assert.strictEqual(c.length, n);      assert(!r.readableFlowing);      then();    }  })();}
// Then we listen to some data events.function onData() {  expectEndingData -= 100;  console.error('onData');  let seen = 0;  r.on('data', function od(c) {    seen += c.length;    if (seen >= 100) {      // Seen enough      r.removeListener('data', od);      r.pause();      if (seen > 100) {        // Oh no, seen too much!        // Put the extra back.        const diff = seen - 100;        r.unshift(c.slice(c.length - diff));        console.error('seen too much', seen, diff);      }
      // Nothing should be lost in-between.      setImmediate(pipeLittle);    }  });}
// Just pipe 200 bytes, then unshift the extra and unpipe.function pipeLittle() {  expectEndingData -= 200;  console.error('pipe a little');  const w = new Writable();  let written = 0;  w.on('finish', () => {    assert.strictEqual(written, 200);    setImmediate(read1234);  });  w._write = function(chunk, encoding, cb) {    written += chunk.length;    if (written >= 200) {      r.unpipe(w);      w.end();      cb();      if (written > 200) {        const diff = written - 200;        written -= diff;        r.unshift(chunk.slice(chunk.length - diff));      }    } else {      setImmediate(cb);    }  };  r.pipe(w);}
// Now read 1234 more bytes.function read1234() {  readn(1234, resumePause);}
function resumePause() {  console.error('resumePause');  // Don't read anything, just resume and re-pause a whole bunch.  r.resume();  r.pause();  r.resume();  r.pause();  r.resume();  r.pause();  r.resume();  r.pause();  r.resume();  r.pause();  setImmediate(pipe);}

function pipe() {  console.error('pipe the rest');  const w = new Writable();  let written = 0;  w._write = function(chunk, encoding, cb) {    written += chunk.length;    cb();  };  w.on('finish', () => {    console.error('written', written, totalPushed);    assert.strictEqual(written, expectEndingData);    assert.strictEqual(totalPushed, expectTotalData);    console.log('ok');  });  r.pipe(w);}