Component-level injectors don't work

[franzeal]

I'm submitting a ...

[x] bug report
[ ] feature request
[ ] support request

Current behavior
In version 5, component-level injectors do not work.

Expected behavior
Component-level injectors should work.

Minimal reproduction of the problem with instructions
Below is a demonstration of component-level injectors. I'm demonstrating a parent/child relationship of wrappers (A) and components (B) (these don't behave differently, which is expected). In the console, each parent/child logs its service dependency. The expectation is that all parent/child log output should have the service, but in the v5 demo the children receive null.

https://stackblitz.com/edit/ngx-formly-ui-bootstrap-component-injectors-v3 (works)
https://stackblitz.com/edit/ngx-formly-ui-bootstrap-component-injectors-v4 (works)
https://stackblitz.com/edit/ngx-formly-ui-bootstrap-component-injectors-v5 (issue)

What is the motivation / use case for changing the behavior?
Trying to address: franzeal/ngx-formly-tabs#2

• Angular version:
  Tested with Angular 6 and 7.

• Browser:
  Chrome 75, Firefox 67

[ilijev07]

Any progress on this one?

[aitboudad]

I'll check it during this week but not sure if I would find a proper fix, the order of creation field component and its wrappers has been changed and we can't revert it.

[ilijev07]

Like a workaround for franzeal/ngx-formly-tabs#2 it can be made with providing TabsetService in the module directly instead of component, I tried and it works fine.

[thiagogjt]

You can provide it on the container component. The drawback is that you cant have more than one tabset in the form...

[aitboudad]

@franzeal the fix should be landed in ngx-formly-tabs for now the only way to make it work is to set the parent as a type instead of wrapper.

• https://stackblitz.com/edit/ngx-formly-ui-bootstrap-component-injectors-v5-n9r5px
• Working example with ngx-formly-tabs https://codesandbox.io/s/angular-7-template-5zw4j?fontsize=14

[franzeal]

@aitboudad that works to an extent, certainly enough that I can address the issue on my end. Wanting to keep the usage consistent, I was surprised to see that it won't work if I change both to types:
https://stackblitz.com/edit/ngx-formly-ui-bootstrap-component-injectors-v5-no-wrappers

[aitboudad]

I think I've got an idea to make it work, let me check it first :)

[aitboudad]

@franzeal in 5.2 version you can declare both as a type, component-level injectors for field type is now supported (only between field type components) so in ngx-formly-tabs the TabsetService provider should be declared in FormlyFieldTabsetComponent in order to work properly.

[franzeal]

@aitboudad I really appreciate it, thank you!