Version 1.5.11 - Providers must be declared in correct sequence or injection fails

[ceberz]

I'm submitting a ...

• bug report
• feature request
• other

Current behavior:
Providers declared on the module must be declared in a sequence that fits their (non-cyclical) dependency graph.

Expected / new behavior:
Provider declaration order should not matter, as the declaration order for post-config entities (service, factory, etc) does not matter.

Minimal reproduction of the problem with instructions:
http://plnkr.co/edit/xfusk4lIevLngt7DAzQO?p=preview

AngularJS version: 1.5.11

Browser: [all | Chrome XX | Firefox XX | Edge XX | IE XX | Safari XX | Mobile Chrome XX | Android X.X Web Browser | iOS XX Safari | iOS XX UIWebView | iOS XX WKWebView ]

Anything else:
I tried to find out whether or not this behavior is as intended by checking documentation, but couldn't find an answer.

[gkalpak]

It seems to have been the case since forever (at least as back as 1.2.x). Off the top of my head, I can't think a reason why (other than complicating the implementation a bit). Does anyone know?

cc @petebacondarwin, @Narretz

[Narretz]

Can't remember that this ever came up. I think we put config calls in order or something a few years back, but that must have been post 1.2, too

[ceberz]

For what it's worth with respect to priority and frequency: injecting providers into other providers is rare enough of a thing that this is literally the first time I've tried to do it in five years.

[petebacondarwin]

By the time we arrive at using any service, all the services have been registered (via their providers, etc), so we never have a problem with resolving their dependencies.

Compare to providers, which are run as soon as they are registered:

function provider(name, provider_) {
    ...
    if (isFunction(provider_) || isArray(provider_)) {
      provider_ = providerInjector.instantiate(provider_);
    }
    ...
  }

I guess that it would be quite an upheaval to make providers "lazy" so that we only ran their factory function when the service that they provide is requested?

[Narretz]

I think we should document this and leave it as is.