actions: improve error message when action needs to be referenced by instance

[mildwonkey]

Terraform Version

1.14.0

Use Cases

When an action is expanded with count or for_each, it can only be referenced inside an action_trigger by instance. The error message could be clearer - currently it returns Action instance was not found in the current context. Terraform could recognize that the user is referencing an action and hint that they should be referencing an instance of that action (in theory, at least).

Attempted Solutions

👋🏻

Proposal

No response

References

No response

[devhindo]

Can I work on this?

[crw]

@devhindo please start here! https://github.com/hashicorp/terraform/blob/main/.github/CONTRIBUTING.md

Thanks!

[devhindo]

Hi @mildwonkey! What do you think about changing the error message to something like that?

Detail:   "The referenced action could not be found. If the action uses 'count' or 'for_each', ensure you reference a specific instance, such as action.example[0] or action.example[\"key\"].",

internal/terraform/node_action_trigger_instance_plan.go/line:110

Does this sound like a good idea? @crw

[devhindo]

hi can I get a review @crw @mildwonkey @daniel @DanielMSchmidt