public function testReturnObservableSubscribeTwice() { $o = new ReturnObservable("The Value"); $goodCount = 0; $o->subscribe(new CallbackObserver(function ($x) use(&$goodCount) { $this->assertEquals("The Value", $x); $goodCount++; })); $o->subscribe(new CallbackObserver(function ($x) use(&$goodCount) { $this->assertEquals("The Value", $x); $goodCount++; })); $this->assertEquals(2, $goodCount); }