Add support for computed property query param values

[SeanSmithers]

e.g.:

<a href="{{href-to 'apps.app.inbox.search.conversations' app (query-params tag=tagOrSegment.id)}}">{{unbound tagOrSegment.name}}</a>

Results in: ...inbox/search/conversations?tag=%5Bobject%20Object%5D

[GavinJoyce]

@SeanSmithers Can you still reproduce this? I tried to in the branch, but it seems to work fine:

#22

Perhaps you could modify my branch to include an example of it not working?

[SeanSmithers]

@GavinJoyce No, I can't seem to reproduce it now, I pushed something to your branch to demonstrate what I was trying

[GavinJoyce]

I think this may only be an issue in Ember 1.x. I can't reproduce it in ember 2.0. I'll confirm soon

[dongintercom]

@GavinJoyce @SeanSmithers

This behaviour (%5Bobject%20Object%5D) can be reproduced when the attribute is KeyStream object and its value is not immediately available (e.g like an Ember model). In this case, link-to needs to be used because it has a view and can refresh the view when the value changes (gets notified from subscription).

href-to is supposed to be a lightweight alternative, if I understand correctly, subscribing to the changes of some lazy attribute and re-render will not be supported since it would require a view, and href-to is a helper that can generate links in a straight-forward way.

So we maybe would need to state this corner case explicitly in the README, what do you think?

[GavinJoyce]

@dongintercom thanks, that's useful. I'll use this to create a failing test and use that to fix the issue

[buschtoens]

[...] subscribing to the changes of some lazy attribute and re-render will not be supported since it would require a view [...]

Not necessarily, I believe.

Quoting from emberjs/ember.js#11021 (comment):

For anyone coming across this later, helpers in Ember 2.x are now "real" objects and can have access to services (via Ember.inject.service or initializer based injections).

Example:

export default Ember.Helper.extend({
 i18n: Ember.inject.service('i18n'),

 compute(params, hash) {
   let i18n = this.get('i18n');
   // stuff here
 }
});

I haven't actually tested this, but we should be able to wait for Promise resolution and call recompute.

However, we then would have to actually subclass Helper instead of using plain objects which could lead to some slight performance degradation. If my assumption checks out, maybe we could provide a second promise-aware helper?

[shelby-carter]

Just in case if someone needs it right now https://discuss.emberjs.com/t/passing-dynamic-query-params-as-an-object-in-link-to-helper/9136/3