By tolerating ProviderSchema and ProvisionerSchema potentially returning
errors, we can slightly simplify EvalContextBuiltin by having it retrieve
individual schemas when needed directly from the "Plugins" object.
EvalContextBuiltin already needs to be holding a contextPlugins instance
for other reasons anyway, so this allows us to get the same result with
fewer moving parts.
Here we wire through the "move results" into the graph walk data
structures so that all of the the nodes which produce
plans.ResourceInstanceChange values can capture the "PrevRunAddr" for
each resource instance.
This doesn't actually quite work yet, because the logic in Context.Plan
isn't actually correct and so the updated state from
refactoring.ApplyMoves isn't actually visible as the "previous run state".
For that reason, the context test in this commit is currently skipped,
with the intent of re-enabling it once the updated state is properly
propagating into the plan graph walk and thus we can actually react to
the result of the move while choosing actions for those addresses.
This is part of a general effort to move all of Terraform's non-library
package surface under internal in order to reinforce that these are for
internal use within Terraform only.
If you were previously importing packages under this prefix into an
external codebase, you could pin to an earlier release tag as an interim
solution until you've make a plan to achieve the same functionality some
other way.