Wenqi Chen

@volvachev Could you add a unit test?

https://github.com/volvachev/ng-zorro-antd/blob/e35a516aa5d8b7838312cfdd71e83f09fb8ea82e/components/date-picker/date-picker.component.ts#L539 Try `this.cdr.detectChanges()` here.

@UncleDave CI failed, you should make it run successfully first.

@UncleDave Run `npm run test` and `npm run build` can reproduce this.

@UncleDave Maybe you should merge the latest code of master and re-install dependencies?

@drackp2m Also need to rebase master

@vthinkxie Plz take a look.

@drackp2m Oh sorry for the misunderstood, but it is better to restore `monthFormat`, even if the en_US does not have it. By the way, remember to rebase master.

@drackp2m Still has build errors, you should rebase the remote master of ng-zorro.

> One last question then: What language, or what file could I use to know which translation keys are really valid? Chinese maybe? @drackp2m The en_US is the valid one,...