fix(bufferCount): set default value for skip argument, do not emit empty buffer at the end

Author: kwonoj

spec/operators/bufferCount-spec.js

@@ -17,4 +17,17 @@ describe('Observable.prototype.bufferCount', function () {
         expect(w).toEqual(expected.shift())
       }, null, done);
   }, 2000);
+  
+  it('should emit buffers at buffersize of intervals if not specified', function (done) {
+    var expected = [
+      [0, 1],
+      [2, 3],
+      [4, 5]
+    ];
+    Observable.range(0, 6)
+      .bufferCount(2)
+      .subscribe(function (w) {
+        expect(w).toEqual(expected.shift())
+      }, null, done);
+  }, 2000);
 });

src/operators/bufferCount.ts

@@ -33,7 +33,7 @@ class BufferCountSubscriber<T> extends Subscriber<T> {
     const count = (this.count += 1);
     const destination = this.destination;
     const bufferSize = this.bufferSize;
-    const startBufferEvery = this.startBufferEvery;
+    const startBufferEvery = (this.startBufferEvery == null) ? bufferSize : this.startBufferEvery;
     const buffers = this.buffers;
     const len = buffers.length;
     let remove = -1;
@@ -64,7 +64,10 @@ class BufferCountSubscriber<T> extends Subscriber<T> {
     const destination = this.destination;
     const buffers = this.buffers;
     while (buffers.length > 0) {
-      destination.next(buffers.shift());
+      var buffer = buffers.shift();
+      if (buffer.length > 0) {
+        destination.next(buffer);
+      }
     }
     destination.complete();
   }