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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');const assert = require('assert');const { Readable, Writable, PassThrough } = require('stream');
{  let ticks = 17;
  const rs = new Readable({    objectMode: true,    read: () => {      if (ticks-- > 0)        return process.nextTick(() => rs.push({}));      rs.push({});      rs.push(null);    }  });
  const ws = new Writable({    highWaterMark: 0,    objectMode: true,    write: (data, end, cb) => setImmediate(cb)  });
  rs.on('end', common.mustCall());  ws.on('finish', common.mustCall());  rs.pipe(ws);}
{  let missing = 8;
  const rs = new Readable({    objectMode: true,    read: () => {      if (missing--) rs.push({});      else rs.push(null);    }  });
  const pt = rs    .pipe(new PassThrough({ objectMode: true, highWaterMark: 2 }))    .pipe(new PassThrough({ objectMode: true, highWaterMark: 2 }));
  pt.on('end', () => {    wrapper.push(null);  });
  const wrapper = new Readable({    objectMode: true,    read: () => {      process.nextTick(() => {        let data = pt.read();        if (data === null) {          pt.once('readable', () => {            data = pt.read();            if (data !== null) wrapper.push(data);          });        } else {          wrapper.push(data);        }      });    }  });
  wrapper.resume();  wrapper.on('end', common.mustCall());}
{  // Only register drain if there is backpressure.  const rs = new Readable({ read() {} });
  const pt = rs    .pipe(new PassThrough({ objectMode: true, highWaterMark: 2 }));  assert.strictEqual(pt.listenerCount('drain'), 0);  pt.on('finish', () => {    assert.strictEqual(pt.listenerCount('drain'), 0);  });
  rs.push('asd');  assert.strictEqual(pt.listenerCount('drain'), 0);
  process.nextTick(() => {    rs.push('asd');    assert.strictEqual(pt.listenerCount('drain'), 0);    rs.push(null);    assert.strictEqual(pt.listenerCount('drain'), 0);  });}