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Changes links to internal/terraform in architecture.md

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docs/architecture.md
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@ -85,12 +85,12 @@ specified in the operation, then uses the _config loader_ to load and do
initial processing/validation of the configuration specified in the
operation. It then uses these, along with the other settings given in the
operation, to construct a
[`terraform.Context`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#Context),
[`terraform.Context`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#Context),
which is the main object that actually performs OpenTF operations.
The `local` backend finally calls an appropriate method on that context to
begin execution of the relevant command, such as
[`Plan`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#Context.Plan)
[`Plan`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#Context.Plan)
or
[`Apply`](), which in turn constructs a graph using a _graph builder_,
described in a later section.
@ -160,7 +160,7 @@ kind of arbitrary blob store.
## Graph Builder
A _graph builder_ is called by a
[`terraform.Context`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#Context)
[`terraform.Context`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#Context)
method (e.g. `Plan` or `Apply`) to produce the graph that will be used
to represent the necessary steps for that operation and the dependency
relationships between them.
@ -170,7 +170,7 @@ In most cases, the
graphs each represent a specific object in the configuration, or something
derived from those configuration objects. For example, each `resource` block
in the configuration has one corresponding
[`GraphNodeConfigResource`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#GraphNodeConfigResource)
[`GraphNodeConfigResource`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#GraphNodeConfigResource)
vertex representing it in the "plan" graph. (OpenTF Core uses terminology
inconsistently, describing graph _vertices_ also as graph _nodes_ in various
places. These both describe the same concept.)
@ -187,23 +187,23 @@ graph from the set of changes described in the plan that is being applied.
The graph builders all work in terms of a sequence of _transforms_, which
are implementations of
[`terraform.GraphTransformer`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#GraphTransformer).
[`terraform.GraphTransformer`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#GraphTransformer).
Implementations of this interface just take a graph and mutate it in any
way needed, and so the set of available transforms is quite varied. Some
important examples include:
* [`ConfigTransformer`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#ConfigTransformer),
* [`ConfigTransformer`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#ConfigTransformer),
which creates a graph vertex for each `resource` block in the configuration.
* [`StateTransformer`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#StateTransformer),
* [`StateTransformer`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#StateTransformer),
which creates a graph vertex for each resource instance currently tracked
in the state.
* [`ReferenceTransformer`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#ReferenceTransformer),
* [`ReferenceTransformer`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#ReferenceTransformer),
which analyses the configuration to find dependencies between resources and
other objects and creates any necessary "happens after" edges for these.
* [`ProviderTransformer`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#ProviderTransformer),
* [`ProviderTransformer`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#ProviderTransformer),
which associates each resource or resource instance with exactly one
provider configuration (implementing
[the inheritance rules](https://www.placeholderplaceholderplaceholder.io/docs/language/modules/develop/providers.html))
@ -217,7 +217,7 @@ builder uses a different subset of these depending on the needs of the
operation that is being performed.
The result of graph building is a
[`terraform.Graph`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#Graph), which
[`terraform.Graph`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#Graph), which
can then be processed using a _graph walker_.
## Graph Walk
@ -229,13 +229,13 @@ itself is implemented in
(where "DAG" is short for [_Directed Acyclic Graph_](https://en.wikipedia.org/wiki/Directed_acyclic_graph)), in
[`AcyclicGraph.Walk`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/dag#AcyclicGraph.Walk).
However, the "interesting" OpenTF walk functionality is implemented in
[`terraform.ContextGraphWalker`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#ContextGraphWalker),
[`terraform.ContextGraphWalker`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#ContextGraphWalker),
which implements a small set of higher-level operations that are performed
during the graph walk:
* `EnterPath` is called once for each module in the configuration, taking a
module address and returning a
[`terraform.EvalContext`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#EvalContext)
[`terraform.EvalContext`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#EvalContext)
that tracks objects within that module. `terraform.Context` is the _global_
context for the entire operation, while `terraform.EvalContext` is a
context for processing within a single module, and is the primary means
@ -287,20 +287,20 @@ implementation can take any action against the `EvalContext`.
The implementation of `terraform.EvalContext` used in real processing
(as opposed to testing) is
[`terraform.BuiltinEvalContext`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#BuiltinEvalContext).
[`terraform.BuiltinEvalContext`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#BuiltinEvalContext).
It provides coordinated access to plugins, the current state, and the current
plan via the `EvalContext` interface methods.
In order to be executed, a vertex must implement
[`terraform.GraphNodeExecutable`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#GraphNodeExecutable),
[`terraform.GraphNodeExecutable`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#GraphNodeExecutable),
which has a single `Execute` method that handles. There are numerous `Execute`
implementations with different behaviors, but some prominent examples are:
* [NodePlannableResource.Execute](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#NodePlannableResourceInstance.Execute), which handles the `plan` operation.
* [NodePlannableResource.Execute](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#NodePlannableResourceInstance.Execute), which handles the `plan` operation.
* [`NodeApplyableResourceInstance.Execute`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#NodeApplyableResourceInstance.Execute), which handles the main `apply` operation.
* [`NodeApplyableResourceInstance.Execute`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#NodeApplyableResourceInstance.Execute), which handles the main `apply` operation.
* [`NodeDestroyResourceInstance.Execute`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#EvalWriteState), which handles the main `destroy` operation.
* [`NodeDestroyResourceInstance.Execute`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#EvalWriteState), which handles the main `destroy` operation.
A vertex must complete successfully before the graph walk will begin evaluation
for other vertices that have "happens after" edges. Evaluation can fail with one
@ -367,7 +367,7 @@ known when the main graph is constructed, but become known while evaluating
other vertices in the main graph.
This special behavior applies to vertex objects that implement
[`terraform.GraphNodeDynamicExpandable`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/terraform#GraphNodeDynamicExpandable).
[`terraform.GraphNodeDynamicExpandable`](https://pkg.go.dev/github.com/placeholderplaceholderplaceholder/opentf/internal/opentf#GraphNodeDynamicExpandable).
Such vertices have their own nested _graph builder_, _graph walk_,
and _vertex evaluation_ steps, with the same behaviors as described in these
sections for the main graph. The difference is in which graph transforms