DefinitelyTyped/types/async-writer/async-writer-tests.ts

import asyncWriter = require('async-writer');
import stream = require('stream');

class TestStream extends stream.Writable {
	constructor(public output: string) {
		super();
	}
	_write(data: string, encoding: string, callback: Function) {
		this.output += data;
		callback();
	}
}

// Simple usage
function simpleUsage(callback: () => void) {
	var output = '';
	let testStream = new TestStream(output);
	let out = asyncWriter.create(testStream)
	.on('error', (err: Error) => {
		console.error(err);
	})
	.on('finish', () => {
		console.log(testStream.output);
		callback();
	})

	out.write('A');
	out.write('B');
	out.write('C');
	out.end();
}


// Asynchronous, out-of-order writing
function asyncUsage(callback: () => void) {
	var output = '';
	let testStream = new TestStream(output);
	let out = asyncWriter.create(testStream)
	.on('error', (err: Error) => {
		console.error(err);
	})
	.on('finish', () => {
		console.log(testStream.output);
		callback();
	})

	out.write('A');

	let asyncOut = out.beginAsync();
	setTimeout(() => {
		asyncOut.write('B');
		asyncOut.end();
	}, 1000);

	out.write('C');
	out.end();
}

// run test
simpleUsage(() => {
	asyncUsage(() => {
		console.log('DONE');
	});
});