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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 } = require('stream');
{  // Check that strings are saved as Buffer  const readable = new Readable({ read() {} });
  const string = 'abc';
  readable.on('data', common.mustCall((chunk) => {    assert(Buffer.isBuffer(chunk));    assert.strictEqual(chunk.toString('utf8'), string);  }, 1));
  readable.unshift(string);
}
{  // Check that data goes at the beginning  const readable = new Readable({ read() {} });  const unshift = 'front';  const push = 'back';
  const expected = [unshift, push];  readable.on('data', common.mustCall((chunk) => {    assert.strictEqual(chunk.toString('utf8'), expected.shift());  }, 2));

  readable.push(push);  readable.unshift(unshift);}
{  // Check that buffer is saved with correct encoding  const readable = new Readable({ read() {} });
  const encoding = 'base64';  const string = Buffer.from('abc').toString(encoding);
  readable.on('data', common.mustCall((chunk) => {    assert.strictEqual(chunk.toString(encoding), string);  }, 1));
  readable.unshift(string, encoding);
}
{
  const streamEncoding = 'base64';
  function checkEncoding(readable) {
    // chunk encodings    const encodings = ['utf8', 'binary', 'hex', 'base64'];    const expected = [];
    readable.on('data', common.mustCall((chunk) => {      const { encoding, string } = expected.pop();      assert.strictEqual(chunk.toString(encoding), string);    }, encodings.length));
    for (const encoding of encodings) {      const string = 'abc';
      // If encoding is the same as the state.encoding the string is      // saved as is      const expect = encoding !== streamEncoding ?        Buffer.from(string, encoding).toString(streamEncoding) : string;
      expected.push({ encoding, string: expect });
      readable.unshift(string, encoding);    }  }
  const r1 = new Readable({ read() {} });  r1.setEncoding(streamEncoding);  checkEncoding(r1);
  const r2 = new Readable({ read() {}, encoding: streamEncoding });  checkEncoding(r2);
}
{  // Both .push & .unshift should have the same behaviour  // When setting an encoding, each chunk should be emitted with that encoding  const encoding = 'base64';
  function checkEncoding(readable) {    const string = 'abc';    readable.on('data', common.mustCall((chunk) => {      assert.strictEqual(chunk, Buffer.from(string).toString(encoding));    }, 2));
    readable.push(string);    readable.unshift(string);  }
  const r1 = new Readable({ read() {} });  r1.setEncoding(encoding);  checkEncoding(r1);
  const r2 = new Readable({ read() {}, encoding });  checkEncoding(r2);
}
{  // Check that ObjectMode works  const readable = new Readable({ objectMode: true, read() {} });
  const chunks = ['a', 1, {}, []];
  readable.on('data', common.mustCall((chunk) => {    assert.strictEqual(chunk, chunks.pop());  }, chunks.length));
  for (const chunk of chunks) {    readable.unshift(chunk);  }}
{
  // Should not throw: https://github.com/nodejs/node/issues/27192  const highWaterMark = 50;  class ArrayReader extends Readable {    constructor(opt) {      super({ highWaterMark });      // The error happened only when pushing above hwm      this.buffer = new Array(highWaterMark * 2).fill(0).map(String);    }    _read(size) {      while (this.buffer.length) {        const chunk = this.buffer.shift();        if (!this.buffer.length) {          this.push(chunk);          this.push(null);          return true;        }        if (!this.push(chunk))          return;      }    }  }
  function onRead() {    while (null !== (stream.read())) {      // Remove the 'readable' listener before unshifting      stream.removeListener('readable', onRead);      stream.unshift('a');      stream.on('data', (chunk) => {        console.log(chunk.length);      });      break;    }  }
  const stream = new ArrayReader();  stream.once('readable', common.mustCall(onRead));  stream.on('end', common.mustCall(() => {}));
}