asDiagram('buffer')('should emit buffers that close and reopen', () => {
   const a =    hot('-a-b-c-d-e-f-g-h-i-|');
   const b =    hot('-----B-----B-----B-|');
   const expected = '-----x-----y-----z-|';
   const expectedValues = {
     x: ['a', 'b', 'c'],
     y: ['d', 'e', 'f'],
     z: ['g', 'h', 'i']
   };
   expectObservable(a.pipe(buffer(b))).toBe(expected, expectedValues);
 });

  it('should unsubscribe notifier when source unsubscribed', () => {
    const a =    hot('-a-b-c-d-e-f-g-h-i-|');
    const b =    hot('-----1-----2-----3-|');
    const bsubs =    '^    !';
    const expected = '-----(x|)';
    const expectedValues = {
      x: ['a', 'b', 'c'],
    };

    expectObservable(a.pipe(buffer(b), take(1))).toBe(expected, expectedValues);
    expectSubscriptions(b.subscriptions).toBe(bsubs);
  });

 buffer1() {
   // Create an observable that emits a value every second
   const myInterval = interval(1000);
   // Create an observable that emits every time document is clicked
   const bufferBy = fromEvent(document, 'click');
   /*
     Collect all values emitted by our interval observable until we click document.
     This will cause the bufferBy Observable to emit a value, satisfying the buffer.
     Pass us all collected values since last buffer as an array.
   */
   const myBufferedInterval = myInterval.pipe(buffer(bufferBy));
   // Print values to console
   // ex. output: [1,2,3] ... [4,5,6,7,8]
   const subscribe = myBufferedInterval.subscribe(val =>
     console.log(' Buffered Values:', val)
   );
 }