configs: Fix provider lookup local name mismatch

[alisdair]

When a resource has no provider argument specified, its provider is derived from the implied provider type based on the resource type. For example, a boop_instance resource has an implied provider local name of boop. Correspondingly, its provider configuration is specified with a provider "boop" block.

However, users can use the required_providers configuration to give a different local name to a given provider than its defined type. For example, a provider may be published at foobar/beep, but provide resources such as boop_instance. The most convenient way to use this provider is with a required_providers map:

terraform {
  required_providers {
    boop = {
      source = "foobar/beep"
    }
  }
}

Once that local name is defined, it is used for provider configuration (a provider "boop" block, not provider "beep"). It should also be used when looking up a resource's provider configuration or provider.

This commit fixes a bug with this edge case, where previously we were looking up the local provider configuration block using the resource's assigned provider type. Instead, if no provider argument is specified, we should be using the implied provider type, as that is what binds the resource to the local provider configuration.

Specifically fixes #26868, where a onepassword provider offering resources like onepassword_item_login has been published at milosbackonja/1password. With this commit, the provider mapping in the original report works as expected (and documented). More details and diagnosis over in the issue.

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Assuming this passes review, I think this may be a candidate for an 0.14 backport, despite the very close RC. Any concerns with backporting?

[codecov]

Codecov Report

Merging #26871 (45671a3) into master (7c98be9) will increase coverage by 0.00%.
The diff coverage is 0.00%.

Impacted Files	Coverage Δ
configs/resource.go	80.46% <0.00%> (ø)
terraform/eval_apply.go	73.27% <0.00%> (-0.61%)	⬇️
terraform/evaluate.go	52.89% <0.00%> (-0.42%)	⬇️
terraform/evaluate_valid.go	79.57% <0.00%> (+5.63%)	⬆️

[mildwonkey]

Oof! Good find! Every time I think we found all of those old references to r.Provider.Type in place of the ImpliedProvider() func, another one pops up.

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

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