         strings = []
         error = nil
         done = nil
-        
+
         subject?.subscribe(
             queue: nil,
-            onNext: { [weak self] string in self?.strings?.append(string) },
-            onError: { error in self.error = error },
+            onNext: { [weak self] in self?.strings?.append($0) },
+            onError: { self.error = $0 },
             onDone: { self.done = true }
         )
     }
-    
+
     func testOnErrorIsRun() {
         XCTAssertEqual((error as? TestError), TestError.test)
     }

            onError: { error in newError = error },
            onDone: { self.done = true }
        )
        
        XCTAssertNotNil(newError as? TestError)
        XCTAssertEqual(newError as? TestError, error as? TestError)
        XCTAssertNil(done)

        subject?.on(.next("1"))
        XCTAssertEqual(strings?.count, 0)
    }

    func testOnDoneIsNotRun() {
        XCTAssertNil(done)
    }

    func testFiresStoppedEventOnSubscribe() {
        var newError: Error? = nil
        done = nil
