How to use the @xviz/io.MemorySourceSink function in @xviz/io

test('XVIZJSONReader#default-ctor', t => {
  /* eslint-disable no-unused-vars */
  // Ensure no parameter ctor
  const source = new MemorySourceSink();
  const binBuilder = new XVIZJSONReader(source);
  t.end();
  /* eslint-enable no-unused-vars */
});

test('XVIZBinaryReader#default-ctor', t => {
  /* eslint-disable no-unused-vars */
  // Ensure no parameter ctor
  const source = new MemorySourceSink();
  const binBuilder = new XVIZBinaryReader(source);
  t.end();
  /* eslint-enable no-unused-vars */
});

].forEach(frame => {
    // Test that each "points" field is properly replaced.
    const sink = new MemorySourceSink();
    const writer = new XVIZBinaryWriter(sink);

    writer.writeMessage(0, frame);

    t.ok(sink.has('2-frame.glb'), 'wrote binary frame');

    const data = sink.readSync('2-frame.glb');
    const msg = new XVIZData(data).message();
    const writtenPoints = msg.data.updates[0].primitives['/test/points'].points[0];

    t.ok(writtenPoints.points, 'Has points');
    t.ok(writtenPoints.colors, 'Has colors');

    t.equals(writtenPoints.points[0], 1, 'point 1 matches input data');
    t.equals(writtenPoints.points[3], 2, 'point 2 matches input data');
    t.equals(writtenPoints.points[6], 3, 'point 3  matches input data');

test('XVIZJSONReader#readMetadata', t => {
  const source = new MemorySourceSink();
  const binBuilder = new XVIZJSONReader(source);

  const testData = {
    version: '2.0.0'
  };

  source.writeSync('1-frame.json', testData);
  const result = binBuilder.readMetadata();

  t.deepEquals(result, testData, 'readMetadata works with object');
  t.end();
});

test('XVIZWriter#default-ctor messages close()', t => {
  const sink = new MemorySourceSink();
  const jsBuilder = new XVIZJSONWriter(sink);
  const binBuilder = new XVIZBinaryWriter(sink);

  const data = SAMPLE_STATE_UPDATE;

  for (const builder of [jsBuilder, binBuilder]) {
    builder.writeMessage(0, data);
    builder.close();

    t.ok(sink.has('0-frame.json'), 'wrote index for messages');

    const expected = {
      timing: [[100, 100, 0, '2-frame']]
    };

    t.deepEquals(

test('XVIZBinaryReader#readMessage', t => {
  const source = new MemorySourceSink();
  const binBuilder = new XVIZBinaryReader(source);

  const testData = {
    type: 'xviz/state_update',
    data: {
      update_type: 'snapshot'
    }
  };

  source.writeSync('2-frame.glb', testData);
  const result = binBuilder.readMessage(0);

  t.deepEquals(result, testData, 'readMessage(0) works with object');
  t.end();
});

function testWriterThrows(t, testCase, Writer) {
  const sink = new MemorySourceSink();
  const writer = new Writer(sink, testCase.options);

  if (testCase.preTest) {
    testCase.preTest(t, testCase, writer, sink);
  }

  t.throws(
    () => writer.writeMessage(0, testCase.data),
    testCase.exceptionRegex,
    testCase.testMessage
  );

  if (testCase.postTest) {
    testCase.postTest(t, testCase, writer, sink);
  }
}

function testWriter(t, testCase, Writer, suffix) {
  const sink = new MemorySourceSink();
  const writer = new Writer(sink, testCase.options);

  if (testCase.preTest) {
    testCase.preTest(t, testCase, writer, sink);
  }

  let lookup = null;
  let resultType = null;
  if (testCase.type === 'm') {
    lookup = '1-frame';
    resultType = 'metadata';
    writer.writeMetadata(testCase.data);
  } else if (testCase.type === 'f') {
    lookup = '2-frame';
    resultType = 'state_update';
    writer.writeMessage(0, testCase.data);

export function getBinaryTestDataSource() {
  const source = new MemorySourceSink();
  source.writeSync('0-frame.json', index);
  source.writeSync('1-frame.glb', metadata);
  source.writeSync('2-frame.glb', msg1);
  source.writeSync('3-frame.glb', msg2);

  return source;
}