describe('QueueRunner', function() {
  it('validates that queueableFns are truthy', function() {
    expect(function() {
      new privateUnderTest.QueueRunner({
        queueableFns: [undefined]
      });
    }).toThrowError('Received a falsy queueableFn');
  });

  it('validates that queueableFns have fn properties', function() {
    expect(function() {
      new privateUnderTest.QueueRunner({
        queueableFns: [{ fn: undefined }]
      });
    }).toThrowError('Received a queueableFn with no fn');
  });

  it("runs all the functions it's passed", function() {
    const calls = [];
    const queueableFn1 = { fn: jasmine.createSpy('fn1') };
    const queueableFn2 = { fn: jasmine.createSpy('fn2') };
    const queueRunner = new privateUnderTest.QueueRunner({
      queueableFns: [queueableFn1, queueableFn2]
    });
    queueableFn1.fn.and.callFake(function() {
      calls.push('fn1');
    });
    queueableFn2.fn.and.callFake(function() {
      calls.push('fn2');
    });

    queueRunner.execute();

    expect(calls).toEqual(['fn1', 'fn2']);
  });

  it("calls each function with a consistent 'this'-- an empty object", function() {
    const queueableFn1 = { fn: jasmine.createSpy('fn1') };
    const queueableFn2 = { fn: jasmine.createSpy('fn2') };
    let asyncContext;
    const queueableFn3 = {
      fn: function(done) {
        asyncContext = this;
        done();
      }
    };
    const queueRunner = new privateUnderTest.QueueRunner({
      queueableFns: [queueableFn1, queueableFn2, queueableFn3]
    });

    queueRunner.execute();

    const context = queueableFn1.fn.calls.first().object;
    expect(context).toEqual(new privateUnderTest.UserContext());
    expect(queueableFn2.fn.calls.first().object).toBe(context);
    expect(asyncContext).toBe(context);
  });

  describe('with an asynchronous function', function() {
    beforeEach(function() {
      jasmine.clock().install();
    });

    afterEach(function() {
      jasmine.clock().uninstall();
    });

    it('supports asynchronous functions, only advancing to next function after a done() callback', function() {
      //TODO: it would be nice if spy arity could match the fake, so we could do something like:
      //createSpy('asyncfn').and.callFake(function(done) {});

      const onComplete = jasmine.createSpy('onComplete');
      const beforeCallback = jasmine.createSpy('beforeCallback');
      const fnCallback = jasmine.createSpy('fnCallback');
      const afterCallback = jasmine.createSpy('afterCallback');
      const queueableFn1 = {
        fn: function(done) {
          beforeCallback();
          setTimeout(done, 100);
        }
      };
      const queueableFn2 = {
        fn: function(done) {
          fnCallback();
          setTimeout(done, 100);
        }
      };
      const queueableFn3 = {
        fn: function(done) {
          afterCallback();
          setTimeout(done, 100);
        }
      };
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn1, queueableFn2, queueableFn3],
        onComplete: onComplete
      });

      queueRunner.execute();

      expect(beforeCallback).toHaveBeenCalled();
      expect(fnCallback).not.toHaveBeenCalled();
      expect(afterCallback).not.toHaveBeenCalled();
      expect(onComplete).not.toHaveBeenCalled();

      jasmine.clock().tick(100);

      expect(fnCallback).toHaveBeenCalled();
      expect(afterCallback).not.toHaveBeenCalled();
      expect(onComplete).not.toHaveBeenCalled();

      jasmine.clock().tick(100);

      expect(afterCallback).toHaveBeenCalled();
      expect(onComplete).not.toHaveBeenCalled();

      jasmine.clock().tick(100);

      expect(onComplete).toHaveBeenCalled();
    });

    it('explicitly fails an async function with a provided fail function and moves to the next function', function() {
      const queueableFn1 = {
        fn: function(done) {
          setTimeout(function() {
            done.fail('foo');
          }, 100);
        }
      };
      const queueableFn2 = { fn: jasmine.createSpy('fn2') };
      const failFn = jasmine.createSpy('fail');
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn1, queueableFn2],
        fail: failFn
      });

      queueRunner.execute();

      expect(failFn).not.toHaveBeenCalled();
      expect(queueableFn2.fn).not.toHaveBeenCalled();

      jasmine.clock().tick(100);

      expect(failFn).toHaveBeenCalledWith('foo');
      expect(queueableFn2.fn).toHaveBeenCalled();
    });

    describe('When next is called with an argument', function() {
      it('explicitly fails and moves to the next function', function() {
        const err = 'anything except undefined';
        const queueableFn1 = {
          fn: function(done) {
            setTimeout(function() {
              done(err);
            }, 100);
          }
        };
        const queueableFn2 = { fn: jasmine.createSpy('fn2') };
        const failFn = jasmine.createSpy('fail');
        const queueRunner = new privateUnderTest.QueueRunner({
          queueableFns: [queueableFn1, queueableFn2],
          fail: failFn
        });

        queueRunner.execute();

        expect(failFn).not.toHaveBeenCalled();
        expect(queueableFn2.fn).not.toHaveBeenCalled();

        jasmine.clock().tick(100);

        expect(failFn).toHaveBeenCalledWith(err);
        expect(queueableFn2.fn).toHaveBeenCalled();
      });

      describe('as a result of a promise', function() {
        describe('and the argument is an Error', function() {
          // Since promise support was added, Jasmine has failed specs that
          // return a promise that resolves to an error. That's probably not
          // the desired behavior but it's also not something we should change
          // except on a major release and with a deprecation warning in
          // advance.
          it('explicitly fails and moves to the next function', function(done) {
            const err = new Error('foo');
            const queueableFn1 = {
              fn: function() {
                return Promise.resolve(err);
              }
            };
            const queueableFn2 = { fn: jasmine.createSpy('fn2') };
            const failFn = jasmine.createSpy('fail');
            const queueRunner = new privateUnderTest.QueueRunner({
              queueableFns: [queueableFn1, queueableFn2],
              fail: failFn,
              onComplete: function() {
                expect(failFn).toHaveBeenCalledWith(err);
                expect(queueableFn2.fn).toHaveBeenCalled();
                done();
              }
            });

            queueRunner.execute();
          });
        });

        describe('and the argument is not an Error', function() {
          it('does not report a failure', function(done) {
            const queueableFn1 = {
              fn: function() {
                return Promise.resolve('not an error');
              }
            };
            const failFn = jasmine.createSpy('fail');
            const queueRunner = new privateUnderTest.QueueRunner({
              queueableFns: [queueableFn1],
              fail: failFn,
              onComplete: function() {
                expect(failFn).not.toHaveBeenCalled();
                done();
              }
            });

            queueRunner.execute();
          });
        });
      });
    });

    it('does not cause an explicit fail if execution is being stopped', function() {
      const err = new privateUnderTest.StopExecutionError('foo');
      const queueableFn1 = {
        fn: function(done) {
          setTimeout(function() {
            done(err);
          }, 100);
        }
      };
      const queueableFn2 = { fn: jasmine.createSpy('fn2') };
      const failFn = jasmine.createSpy('fail');
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn1, queueableFn2],
        fail: failFn
      });

      queueRunner.execute();

      expect(failFn).not.toHaveBeenCalled();
      expect(queueableFn2.fn).not.toHaveBeenCalled();

      jasmine.clock().tick(100);

      expect(failFn).not.toHaveBeenCalled();
      expect(queueableFn2.fn).toHaveBeenCalled();
    });

    it("sets a timeout if requested for asynchronous functions so they don't go on forever", function() {
      const timeout = 3;
      const beforeFn = {
        fn: function(done) {},
        type: 'before',
        timeout: timeout
      };
      const queueableFn = { fn: jasmine.createSpy('fn'), type: 'queueable' };
      const onComplete = jasmine.createSpy('onComplete');
      const onException = jasmine.createSpy('onException');
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [beforeFn, queueableFn],
        onComplete: onComplete,
        onException: onException
      });

      queueRunner.execute();
      expect(queueableFn.fn).not.toHaveBeenCalled();

      jasmine.clock().tick(timeout);

      expect(onException).toHaveBeenCalledWith(jasmine.any(Error));
      expect(queueableFn.fn).toHaveBeenCalled();
      expect(onComplete).toHaveBeenCalled();
    });

    it('does not call onMultipleDone if an asynchrnous function completes after timing out', function() {
      const timeout = 3;
      let queueableFnDone;
      const queueableFn = {
        fn: function(done) {
          queueableFnDone = done;
        },
        type: 'queueable',
        timeout: timeout
      };
      const onComplete = jasmine.createSpy('onComplete');
      const onMultipleDone = jasmine.createSpy('onMultipleDone');
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn],
        onComplete: onComplete,
        onMultipleDone: onMultipleDone
      });

      queueRunner.execute();
      jasmine.clock().tick(timeout);
      queueableFnDone();

      expect(onComplete).toHaveBeenCalled();
      expect(onMultipleDone).not.toHaveBeenCalled();
    });

    it('by default does not set a timeout for asynchronous functions', function() {
      const beforeFn = { fn: function(done) {} };
      const queueableFn = { fn: jasmine.createSpy('fn') };
      const onComplete = jasmine.createSpy('onComplete');
      const onException = jasmine.createSpy('onException');
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [beforeFn, queueableFn],
        onComplete: onComplete,
        onException: onException
      });

      queueRunner.execute();
      expect(queueableFn.fn).not.toHaveBeenCalled();

      jasmine.clock().tick(jasmineUnderTest.DEFAULT_TIMEOUT_INTERVAL);

      expect(onException).not.toHaveBeenCalled();
      expect(queueableFn.fn).not.toHaveBeenCalled();
      expect(onComplete).not.toHaveBeenCalled();
    });

    it('clears the timeout when an async function throws an exception, to prevent additional exception reporting', function() {
      const queueableFn = {
        fn: function(done) {
          throw new Error('error!');
        }
      };
      const onComplete = jasmine.createSpy('onComplete');
      const onException = jasmine.createSpy('onException');
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn],
        onComplete: onComplete,
        onException: onException
      });

      queueRunner.execute();

      expect(onComplete).toHaveBeenCalled();
      expect(onException).toHaveBeenCalled();

      jasmine.clock().tick(jasmineUnderTest.DEFAULT_TIMEOUT_INTERVAL);
      expect(onException.calls.count()).toEqual(1);
    });

    it('clears the timeout when the done callback is called', function() {
      const queueableFn = {
        fn: function(done) {
          done();
        }
      };
      const onComplete = jasmine.createSpy('onComplete');
      const onException = jasmine.createSpy('onException');
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn],
        onComplete: onComplete,
        onException: onException
      });

      queueRunner.execute();

      jasmine.clock().tick(1);
      expect(onComplete).toHaveBeenCalled();

      jasmine.clock().tick(jasmineUnderTest.DEFAULT_TIMEOUT_INTERVAL);
      expect(onException).not.toHaveBeenCalled();
    });

    it('only moves to the next spec the first time you call done', function() {
      const queueableFn = {
        fn: function(done) {
          done();
          done();
        }
      };
      const nextQueueableFn = { fn: jasmine.createSpy('nextFn') };
      const onMultipleDone = jasmine.createSpy('onMultipleDone');
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn, nextQueueableFn],
        onMultipleDone: onMultipleDone
      });

      queueRunner.execute();
      jasmine.clock().tick(1);
      expect(nextQueueableFn.fn.calls.count()).toEqual(1);
      expect(onMultipleDone).toHaveBeenCalled();
    });

    it('does not move to the next spec if done is called after an exception has ended the spec', function() {
      const queueableFn = {
        fn: function(done) {
          setTimeout(done, 1);
          throw new Error('error!');
        }
      };
      const nextQueueableFn = { fn: jasmine.createSpy('nextFn') };
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn, nextQueueableFn]
      });
      queueRunner.execute();
      jasmine.clock().tick(1);
      expect(nextQueueableFn.fn.calls.count()).toEqual(1);
    });

    it('should return a null when you call done', function() {
      // Some promises want handlers to return anything but undefined to help catch "forgotten returns".
      let doneReturn;
      const queueableFn = {
        fn: function(done) {
          doneReturn = done();
        }
      };
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn]
      });

      queueRunner.execute();
      expect(doneReturn).toBe(null);
    });

    it('continues running functions when an exception is thrown in async code without timing out', function() {
      const queueableFn = {
        fn: function(done) {
          throwAsync();
        },
        timeout: 1
      };
      const nextQueueableFn = { fn: jasmine.createSpy('nextFunction') };
      const onException = jasmine.createSpy('onException');
      const globalErrors = {
        pushListener: jasmine.createSpy('pushListener'),
        popListener: jasmine.createSpy('popListener')
      };
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn, nextQueueableFn],
        onException: onException,
        globalErrors: globalErrors
      });
      const throwAsync = function() {
        globalErrors.pushListener.calls.mostRecent().args[0](new Error('foo'));
        jasmine.clock().tick(2);
      };

      nextQueueableFn.fn.and.callFake(function() {
        // should remove the same function that was added
        expect(globalErrors.popListener).toHaveBeenCalledWith(
          globalErrors.pushListener.calls.argsFor(1)[0]
        );
      });

      queueRunner.execute();

      function errorWithMessage(message) {
        return {
          asymmetricMatch: function(other) {
            return new RegExp(message).test(other.message);
          },
          toString: function() {
            return '<Error with message like "' + message + '">';
          }
        };
      }
      expect(onException).not.toHaveBeenCalledWith(
        errorWithMessage(/DEFAULT_TIMEOUT_INTERVAL/)
      );
      expect(onException).toHaveBeenCalledWith(errorWithMessage(/^foo$/));
      expect(nextQueueableFn.fn).toHaveBeenCalled();
    });

    it('handles exceptions thrown while waiting for the stack to clear', function() {
      const queueableFn = {
        fn: function(done) {
          done();
        }
      };
      const errorListeners = [];
      const globalErrors = {
        pushListener: function(f) {
          errorListeners.push(f);
        },
        popListener: function() {
          errorListeners.pop();
        }
      };
      const clearStack = jasmine.createSpyObj('clearStack', ['clearStack']);
      const onException = jasmine.createSpy('onException');
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn],
        globalErrors: globalErrors,
        clearStack: clearStack,
        onException: onException
      });
      const error = new Error('nope');

      queueRunner.execute();
      jasmine.clock().tick();
      expect(clearStack.clearStack).toHaveBeenCalled();
      expect(errorListeners.length).toEqual(1);
      errorListeners[0](error);
      clearStack.clearStack.calls.argsFor(0)[0]();
      expect(onException).toHaveBeenCalledWith(error);
    });
  });

  describe('with a function that returns a promise', function() {
    function StubPromise() {}

    StubPromise.prototype.then = function(resolve, reject) {
      this.resolveHandler = resolve;
      this.rejectHandler = reject;
    };

    beforeEach(function() {
      jasmine.clock().install();
    });

    afterEach(function() {
      jasmine.clock().uninstall();
    });

    it('runs the function asynchronously, advancing once the promise is settled', function() {
      const onComplete = jasmine.createSpy('onComplete');
      const fnCallback = jasmine.createSpy('fnCallback');
      const p1 = new StubPromise();
      const p2 = new StubPromise();
      const queueableFn1 = {
        fn: function() {
          setTimeout(function() {
            p1.resolveHandler();
          }, 100);
          return p1;
        }
      };
      const queueableFn2 = {
        fn: function() {
          fnCallback();
          setTimeout(function() {
            p2.resolveHandler();
          }, 100);
          return p2;
        }
      };
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn1, queueableFn2],
        onComplete: onComplete
      });

      queueRunner.execute();
      expect(fnCallback).not.toHaveBeenCalled();
      expect(onComplete).not.toHaveBeenCalled();

      jasmine.clock().tick(100);

      expect(fnCallback).toHaveBeenCalled();
      expect(onComplete).not.toHaveBeenCalled();

      jasmine.clock().tick(100);

      expect(onComplete).toHaveBeenCalled();
    });

    it('handles a rejected promise like an unhandled exception', function() {
      const promise = new StubPromise();
      const queueableFn1 = {
        fn: function() {
          setTimeout(function() {
            promise.rejectHandler('foo');
          }, 100);
          return promise;
        }
      };
      const queueableFn2 = { fn: jasmine.createSpy('fn2') };
      const onExceptionCallback = jasmine.createSpy('on exception callback');
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn1, queueableFn2],
        onException: onExceptionCallback
      });

      queueRunner.execute();

      expect(onExceptionCallback).not.toHaveBeenCalled();
      expect(queueableFn2.fn).not.toHaveBeenCalled();

      jasmine.clock().tick(100);

      expect(onExceptionCallback).toHaveBeenCalledWith('foo');
      expect(queueableFn2.fn).toHaveBeenCalled();
    });

    it('issues an error if the function also takes a parameter', function() {
      const queueableFn = {
        fn: function(done) {
          return new StubPromise();
        }
      };
      const onException = jasmine.createSpy('onException');
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn],
        onException: onException
      });

      queueRunner.execute();

      expect(onException).toHaveBeenCalledWith(
        new Error(
          'An asynchronous ' +
            'before/it/after function took a done callback but also returned a ' +
            'promise. ' +
            'Either remove the done callback (recommended) or change the function ' +
            'to not return a promise.'
        )
      );
    });

    it('issues a more specific error if the function is `async`', function() {
      async function fn(done) {}
      const onException = jasmine.createSpy('onException');
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [{ fn: fn }],
        onException: onException
      });

      queueRunner.execute();

      expect(onException).toHaveBeenCalledWith(
        new Error(
          'An asynchronous ' +
            'before/it/after function was defined with the async keyword but ' +
            'also took a done callback. Either remove the done callback ' +
            '(recommended) or remove the async keyword.'
        )
      );
    });
  });

  it('passes final errors to exception handlers', function() {
    const error = new Error('fake error');
    const onExceptionCallback = jasmine.createSpy('on exception callback');
    const queueRunner = new privateUnderTest.QueueRunner({
      onException: onExceptionCallback
    });

    queueRunner.execute();
    queueRunner.handleFinalError(error);

    expect(onExceptionCallback).toHaveBeenCalledWith(error);
  });

  it('calls exception handlers when an exception is thrown in a fn', function() {
    const queueableFn = {
      type: 'queueable',
      fn: function() {
        throw new Error('fake error');
      }
    };
    const onExceptionCallback = jasmine.createSpy('on exception callback');
    const queueRunner = new privateUnderTest.QueueRunner({
      queueableFns: [queueableFn],
      onException: onExceptionCallback
    });

    queueRunner.execute();

    expect(onExceptionCallback).toHaveBeenCalledWith(jasmine.any(Error));
  });

  it('continues running the functions even after an exception is thrown in an async spec', function() {
    const queueableFn = {
      fn: function(done) {
        throw new Error('error');
      }
    };
    const nextQueueableFn = { fn: jasmine.createSpy('nextFunction') };
    const queueRunner = new privateUnderTest.QueueRunner({
      queueableFns: [queueableFn, nextQueueableFn]
    });

    queueRunner.execute();
    expect(nextQueueableFn.fn).toHaveBeenCalled();
  });

  describe('When configured with a skip policy', function() {
    it('instantiates the skip policy', function() {
      const SkipPolicy = jasmine.createSpy('SkipPolicy ctor');
      const queueableFns = [{ fn: () => {} }, { fn: () => {} }];

      new privateUnderTest.QueueRunner({
        queueableFns,
        SkipPolicy
      });

      expect(SkipPolicy).toHaveBeenCalledWith(queueableFns);
    });

    it('uses the skip policy to determine which fn to run next', function() {
      const queueableFns = [
        { fn: jasmine.createSpy('fn0') },
        { fn: jasmine.createSpy('fn1') },
        { fn: jasmine.createSpy('fn2').and.throwError(new Error('nope')) },
        { fn: jasmine.createSpy('fn3') }
      ];
      const skipPolicy = jasmine.createSpyObj('skipPolicy', [
        'skipTo',
        'fnErrored'
      ]);
      skipPolicy.skipTo.and.callFake(function(lastRanIx) {
        return lastRanIx === 0 ? 2 : lastRanIx + 1;
      });
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns,
        SkipPolicy: function() {
          return skipPolicy;
        }
      });

      queueRunner.execute();

      expect(skipPolicy.skipTo).toHaveBeenCalledWith(0);
      expect(skipPolicy.skipTo).toHaveBeenCalledWith(2);
      expect(skipPolicy.fnErrored).toHaveBeenCalledWith(2);
      expect(queueableFns[0].fn).toHaveBeenCalled();
      expect(queueableFns[1].fn).not.toHaveBeenCalled();
      expect(queueableFns[2].fn).toHaveBeenCalled();
      expect(queueableFns[3].fn).toHaveBeenCalled();
    });

    it('throws if the skip policy returns the current fn', function() {
      const skipPolicy = { skipTo: i => i };
      const queueableFns = [{ fn: () => {} }];
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns,
        SkipPolicy: function() {
          return skipPolicy;
        }
      });

      expect(function() {
        queueRunner.execute();
      }).toThrowError("Can't skip to the same queueable fn that just finished");
    });
  });

  describe('When configured to complete on first error', function() {
    it('skips to cleanup functions on the first exception', function() {
      const queueableFn = {
        fn: function() {
          throw new Error('error');
        }
      };
      const nextQueueableFn = { fn: jasmine.createSpy('nextFunction') };
      const cleanupFn = {
        fn: jasmine.createSpy('cleanup'),
        type: 'specCleanup'
      };
      const onComplete = jasmine.createSpy('onComplete');
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn, nextQueueableFn, cleanupFn],
        onComplete: onComplete,
        SkipPolicy: privateUnderTest.CompleteOnFirstErrorSkipPolicy
      });

      queueRunner.execute();
      expect(nextQueueableFn.fn).not.toHaveBeenCalled();
      expect(cleanupFn.fn).toHaveBeenCalled();
      expect(onComplete).toHaveBeenCalledWith(
        jasmine.any(privateUnderTest.StopExecutionError)
      );
    });

    it('does not skip when a cleanup function throws', function() {
      const queueableFn = { fn: function() {} };
      const cleanupFn1 = {
        fn: function() {
          throw new Error('error');
        },
        type: 'afterEach'
      };
      const cleanupFn2 = {
        fn: jasmine.createSpy('cleanupFn2'),
        type: 'afterEach'
      };
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [queueableFn, cleanupFn1, cleanupFn2],
        SkipPolicy: privateUnderTest.CompleteOnFirstErrorSkipPolicy
      });

      queueRunner.execute();
      expect(cleanupFn2.fn).toHaveBeenCalled();
    });

    describe('with an asynchronous function', function() {
      beforeEach(function() {
        jasmine.clock().install();
      });

      afterEach(function() {
        jasmine.clock().uninstall();
      });

      it('skips to cleanup functions once the fn completes after an unhandled exception', function() {
        const errorListeners = [];
        let queueableFnDone;
        const queueableFn = {
          fn: function(done) {
            queueableFnDone = done;
          }
        };
        const nextQueueableFn = { fn: jasmine.createSpy('nextFunction') };
        const cleanupFn = {
          fn: jasmine.createSpy('cleanup'),
          type: 'specCleanup'
        };
        const queueRunner = new privateUnderTest.QueueRunner({
          globalErrors: {
            pushListener: function(f) {
              errorListeners.push(f);
            },
            popListener: function() {
              errorListeners.pop();
            }
          },
          queueableFns: [queueableFn, nextQueueableFn, cleanupFn],
          SkipPolicy: privateUnderTest.CompleteOnFirstErrorSkipPolicy
        });

        queueRunner.execute();
        errorListeners[errorListeners.length - 1](new Error('error'));
        expect(cleanupFn.fn).not.toHaveBeenCalled();
        queueableFnDone();
        expect(nextQueueableFn.fn).not.toHaveBeenCalled();
        expect(cleanupFn.fn).toHaveBeenCalled();
      });

      it('skips to cleanup functions when next.fail is called', function() {
        const queueableFn = {
          fn: function(done) {
            done.fail('nope');
          }
        };
        const nextQueueableFn = { fn: jasmine.createSpy('nextFunction') };
        const cleanupFn = {
          fn: jasmine.createSpy('cleanup'),
          type: 'specCleanup'
        };
        const queueRunner = new privateUnderTest.QueueRunner({
          queueableFns: [queueableFn, nextQueueableFn, cleanupFn],
          SkipPolicy: privateUnderTest.CompleteOnFirstErrorSkipPolicy
        });

        queueRunner.execute();
        jasmine.clock().tick();
        expect(nextQueueableFn.fn).not.toHaveBeenCalled();
        expect(cleanupFn.fn).toHaveBeenCalled();
      });

      it('skips to cleanup functions when next is called with an Error', function() {
        const queueableFn = {
          fn: function(done) {
            done(new Error('nope'));
          }
        };
        const nextQueueableFn = { fn: jasmine.createSpy('nextFunction') };
        const cleanupFn = {
          fn: jasmine.createSpy('cleanup'),
          type: 'specCleanup'
        };
        const queueRunner = new privateUnderTest.QueueRunner({
          queueableFns: [queueableFn, nextQueueableFn, cleanupFn],
          SkipPolicy: privateUnderTest.CompleteOnFirstErrorSkipPolicy
        });

        queueRunner.execute();
        jasmine.clock().tick();
        expect(nextQueueableFn.fn).not.toHaveBeenCalled();
        expect(cleanupFn.fn).toHaveBeenCalled();
      });
    });
  });

  it('calls a provided complete callback when done', function() {
    const queueableFn = { fn: jasmine.createSpy('fn') };
    const completeCallback = jasmine.createSpy('completeCallback');
    const queueRunner = new privateUnderTest.QueueRunner({
      queueableFns: [queueableFn],
      onComplete: completeCallback
    });

    queueRunner.execute();

    expect(completeCallback).toHaveBeenCalled();
  });

  describe('clearing the stack', function() {
    beforeEach(function() {
      jasmine.clock().install();
    });

    afterEach(function() {
      jasmine.clock().uninstall();
    });

    it('calls a provided stack clearing function when done', function() {
      const asyncFn = {
        fn: function(done) {
          done();
        }
      };
      const afterFn = { fn: jasmine.createSpy('afterFn') };
      const completeCallback = jasmine.createSpy('completeCallback');
      const clearStack = jasmine.createSpyObj('clearStack', ['clearStack']);
      const queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [asyncFn, afterFn],
        clearStack: clearStack,
        onComplete: completeCallback
      });

      clearStack.clearStack.and.callFake(function(fn) {
        fn();
      });

      queueRunner.execute();
      jasmine.clock().tick();
      expect(afterFn.fn).toHaveBeenCalled();
      expect(clearStack.clearStack).toHaveBeenCalled();
      clearStack.clearStack.calls.argsFor(0)[0]();
      expect(completeCallback).toHaveBeenCalled();
    });
  });

  describe('when user context has not been defined', function() {
    beforeEach(function() {
      const fn = jasmine.createSpy('fn1');

      this.fn = fn;
      this.queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [{ fn: fn }]
      });
    });

    it('runs the functions on the scope of a UserContext', function() {
      let context;
      this.fn.and.callFake(function() {
        context = this;
      });

      this.queueRunner.execute();

      expect(context.constructor).toBe(privateUnderTest.UserContext);
    });
  });

  describe('when user context has been defined', function() {
    beforeEach(function() {
      const fn = jasmine.createSpy('fn1');
      let context;

      this.fn = fn;
      this.context = context = new privateUnderTest.UserContext();
      this.queueRunner = new privateUnderTest.QueueRunner({
        queueableFns: [{ fn: fn }],
        userContext: context
      });
    });

    it('runs the functions on the scope of a UserContext', function() {
      let context;
      this.fn.and.callFake(function() {
        context = this;
      });

      this.queueRunner.execute();

      expect(context).toBe(this.context);
    });
  });
});