Tracking: Third party NPM replacements

In the recent weeks, multiple have requested support for the following two NPM replacements:

• yarn, which has a lot of speed improvements. Many users reported problems using yarn with the CLI in some occasions.
• cnpm, which uses an NPM cache specially made for China. It’s not useful for anyone outside of China itself.

What I suggest is embracing the fact that users can have an angular-cli.json file in their home folder to specify which NPM replacement they want to use.

Something like adding to the configuration:

{ // ...
  "packageManager": "npm"  // or "cnpm" or "yarn"
}

And having special code for some of them when the user creates a new package.

I think this is the cleanest way to do it. If we document it well, users won’t have a problem. They can even replace its value per-project.

cc @IgorMinar

[hansl]

Discussing this more with @IgorMinar, we came to the point where the following would be acceptable:

• On ng new, if we detect either yarn or cnpm, we output a warning message to users, telling them they can ng set --global packageManager=yarn to use it globally with new projects.
• Users can then set it globally and recreate the project, or yarn install locally instead.

NPM is only used when running init and new, and since init is used by new we should just put the warning on init.

[sivabudh]

TL;DR:

ng set --global packageManager=yarn
ng new <your-app-name>