Components: Datepicker dependencies docs

[jgwinner]

Documentation Feedback

When using MatMomentDateModule, it's not obvious how to get it working from the docs. Even googling gets you to slightly droll posts like https://github.com/angular/components/issues/12887

Affected documentation page:

If you go here:
https://material.angular.io/components/datepicker/overview#choosing-a-date-implementation-and-date-format-settings

It says to install moment.

If you go to Moment, it says to do:

npm i moment

You still get an error from import { MatMomentDateModule }

You must also do:

npm i @angular/material-moment-adapter

While Angular could probably say "that's Moment's issue" and Moment could say "No, that's Material's issue" I think it would be best to mention on the doc page here:

https://material.angular.io/components/datepicker/overview#choosing-a-date-implementation-and-date-format-settings

To say:

To install
npm i moment
npm i @angular/material-moment-adapter

In your module:
import { MatMomentDateModule, MomentDateAdapter } from "@angular/material-moment-adapter";

While https://github.com/angular/components/issues/12887 is certainly dead accurate, it shouldn't be necessary to google all over the place due to documentation terseness.

My guess: Most large development projects already have a package.json and an app.module.ts that's just loaded with all kinds of junk, so "it' just works". I was doing a coding challenge and going step by step and ran into this.

There are three other similar bugs, all of them locked, and none with a resolution.

(I do find in general, while the documentation is very beautiful, the "TS" tabs frequently don't show the proper module imports).

Seriously - big thumbs up to the look and feel of the docs, and the amazing completeness in most areas. Let's get it the rest of the way!

[x1c0]

I find this a very good point.

What is not so clear for me is that in one angular project I work, I use mat-datepicker with @angular/material-moment-adapter and I also in code do: import { Moment } from 'moment'; without having it installed through package.json how can this be?

Question for docs, do we really need to install moment?

[devversion]

@x1c0 It might be that another dependency in your project brings in moment. The material-moment-adapter package just has a peer dependency on moment, so moment will never be brought in automatically by the @angular/material-moment-adapter package itself.

I agree though that the documentation about installing moment etc. could be more clear.