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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 { Duplex, Readable, Writable, pipeline } = require('stream');const { Blob } = require('buffer');
{  const d = Duplex.from({    readable: new Readable({      read() {        this.push('asd');        this.push(null);      }    })  });  assert.strictEqual(d.readable, true);  assert.strictEqual(d.writable, false);  d.once('readable', common.mustCall(function() {    assert.strictEqual(d.read().toString(), 'asd');  }));  d.once('end', common.mustCall(function() {    assert.strictEqual(d.readable, false);  }));}
{  const d = Duplex.from(new Readable({    read() {      this.push('asd');      this.push(null);    }  }));  assert.strictEqual(d.readable, true);  assert.strictEqual(d.writable, false);  d.once('readable', common.mustCall(function() {    assert.strictEqual(d.read().toString(), 'asd');  }));  d.once('end', common.mustCall(function() {    assert.strictEqual(d.readable, false);  }));}
{  let ret = '';  const d = Duplex.from(new Writable({    write(chunk, encoding, callback) {      ret += chunk;      callback();    }  }));  assert.strictEqual(d.readable, false);  assert.strictEqual(d.writable, true);  d.end('asd');  d.on('finish', common.mustCall(function() {    assert.strictEqual(d.writable, false);    assert.strictEqual(ret, 'asd');  }));}
{  let ret = '';  const d = Duplex.from({    writable: new Writable({      write(chunk, encoding, callback) {        ret += chunk;        callback();      }    })  });  assert.strictEqual(d.readable, false);  assert.strictEqual(d.writable, true);  d.end('asd');  d.on('finish', common.mustCall(function() {    assert.strictEqual(d.writable, false);    assert.strictEqual(ret, 'asd');  }));}
{  let ret = '';  const d = Duplex.from({    readable: new Readable({      read() {        this.push('asd');        this.push(null);      }    }),    writable: new Writable({      write(chunk, encoding, callback) {        ret += chunk;        callback();      }    })  });  assert.strictEqual(d.readable, true);  assert.strictEqual(d.writable, true);  d.once('readable', common.mustCall(function() {    assert.strictEqual(d.read().toString(), 'asd');  }));  d.once('end', common.mustCall(function() {    assert.strictEqual(d.readable, false);  }));  d.end('asd');  d.once('finish', common.mustCall(function() {    assert.strictEqual(d.writable, false);    assert.strictEqual(ret, 'asd');  }));}
{  const d = Duplex.from(Promise.resolve('asd'));  assert.strictEqual(d.readable, true);  assert.strictEqual(d.writable, false);  d.once('readable', common.mustCall(function() {    assert.strictEqual(d.read().toString(), 'asd');  }));  d.once('end', common.mustCall(function() {    assert.strictEqual(d.readable, false);  }));}
{  // https://github.com/nodejs/node/issues/40497  pipeline(    ['abc\ndef\nghi'],    Duplex.from(async function * (source) {      let rest = '';      for await (const chunk of source) {        const lines = (rest + chunk.toString()).split('\n');        rest = lines.pop();        for (const line of lines) {          yield line;        }      }      yield rest;    }),    async function * (source) { // eslint-disable-line require-yield      let ret = '';      for await (const x of source) {        ret += x;      }      assert.strictEqual(ret, 'abcdefghi');    },    common.mustCall(() => {}),  );}
// Ensure that isDuplexNodeStream was called{  const duplex = new Duplex();  assert.strictEqual(Duplex.from(duplex), duplex);}
// Ensure that Duplex.from works for blobs{  const blob = new Blob(['blob']);  const expectedByteLength = blob.size;  const duplex = Duplex.from(blob);  duplex.on('data', common.mustCall((arrayBuffer) => {    assert.strictEqual(arrayBuffer.byteLength, expectedByteLength);  }));}
// Ensure that given a promise rejection it emits an error{  const myErrorMessage = 'myCustomError';  Duplex.from(Promise.reject(myErrorMessage))    .on('error', common.mustCall((error) => {      assert.strictEqual(error, myErrorMessage);    }));}
// Ensure that given a promise rejection on an async function it emits an error{  const myErrorMessage = 'myCustomError';  async function asyncFn() {    return Promise.reject(myErrorMessage);  }
  Duplex.from(asyncFn)    .on('error', common.mustCall((error) => {      assert.strictEqual(error, myErrorMessage);    }));}
// Ensure that Duplex.from throws an Invalid return value when function is void{  assert.throws(() => Duplex.from(() => {}), {    code: 'ERR_INVALID_RETURN_VALUE',  });}
// Ensure data if a sub object has a readable stream it's duplexified{  const msg = Buffer.from('hello');  const duplex = Duplex.from({    readable: Readable({      read() {        this.push(msg);        this.push(null);      }    })  }).on('data', common.mustCall((data) => {    assert.strictEqual(data, msg);  }));
  assert.strictEqual(duplex.writable, false);}
// Ensure data if a sub object has a writable stream it's duplexified{  const msg = Buffer.from('hello');  const duplex = Duplex.from({    writable: Writable({      write: common.mustCall((data) => {        assert.strictEqual(data, msg);      })    })  });
  duplex.write(msg);  assert.strictEqual(duplex.readable, false);}
// Ensure data if a sub object has a writable and readable stream it's duplexified{  const msg = Buffer.from('hello');
  const duplex = Duplex.from({    readable: Readable({      read() {        this.push(msg);        this.push(null);      }    }),    writable: Writable({      write: common.mustCall((data) => {        assert.strictEqual(data, msg);      })    })  });
  duplex.pipe(duplex)    .on('data', common.mustCall((data) => {      assert.strictEqual(data, msg);      assert.strictEqual(duplex.readable, true);      assert.strictEqual(duplex.writable, true);    }))    .on('end', common.mustCall());}
// Ensure that given readable stream that throws an error it calls destroy{  const myErrorMessage = 'error!';  const duplex = Duplex.from(Readable({    read() {      throw new Error(myErrorMessage);    }  }));  duplex.on('error', common.mustCall((msg) => {    assert.strictEqual(msg.message, myErrorMessage);  }));}
// Ensure that given writable stream that throws an error it calls destroy{  const myErrorMessage = 'error!';  const duplex = Duplex.from(Writable({    write(chunk, enc, cb) {      cb(myErrorMessage);    }  }));
  duplex.on('error', common.mustCall((msg) => {    assert.strictEqual(msg, myErrorMessage);  }));
  duplex.write('test');}