You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: transform_state.go
    path of file: ./repos/terraform/internal/terraform
    
    the code of the file until where you have to start completion: // Copyright (c) HashiCorp, Inc.
// SPDX-License-Identifier: BUSL-1.1

package terraform

import (
	"log"

	"github.com/hashicorp/terraform/internal/states"
)

// StateTransformer is a GraphTransformer that adds the elements of
// the state to the graph.
//
// This transform is used for example by the DestroyPlanGraphBuilder to ensure
// that only resources that are in the state are represented in the graph.
type StateTransformer struct {
	// ConcreteCurrent and ConcreteDeposed are used to specialize the abstract
	// resource instance nodes that this transformer will create.
	//
	// If either of these is nil, the objects of that type will be skipped and
	// not added to the graph at all. It doesn't make sense to use this
	// transformer without setting at least one of these, since that would
	// skip everything and thus be a no-op.
	ConcreteCurrent ConcreteResourceInstanceNodeFunc
	ConcreteDeposed ConcreteResourceInstanceDeposedNodeFunc

	State *states.State
}

func (t *StateTransformer) Transform(g *Graph) error {
	if t.State == nil {
		log.Printf("[TRACE] StateTransformer: state is nil, so nothing to do")
		return nil
	}

	switch {
	case t.ConcreteCurrent != nil && t.ConcreteDeposed != nil:
		log.Printf("[TRACE] StateTransformer: creating nodes f
    
func (t *StateTransformer) Transform(g *Graph) error {
	if t.State == nil {
		log.Printf("[TRACE] StateTransformer: state is nil, so nothing to do")
		return nil
	}

	switch {
	case t.ConcreteCurrent != nil && t.ConcreteDeposed != nil:
		log.Printf("[TRACE] StateTransformer: creating nodes for both current and deposed instance objects")
	case t.ConcreteCurrent != nil:
		log.Printf("[TRACE] StateTransformer: creating nodes for current instance objects only")
	case t.ConcreteDeposed != nil:
		log.Printf("[TRACE] StateTransformer: creating nodes for deposed instance objects only")
	default:
		log.Printf("[TRACE] StateTransformer: pointless no-op call, creating no nodes at all")
	}

	for _, ms := range t.State.Modules {
		for _, rs := range ms.Resources {
			resourceAddr := rs.Addr

			for key, is := range rs.Instances {
				addr := resourceAddr.Instance(key)

				if obj := is.Current; obj != nil && t.ConcreteCurrent != nil {
					abstract := NewNodeAbstractResourceInstance(addr)
					node := t.ConcreteCurrent(abstract)
					g.Add(node)
					log.Printf("[TRACE] StateTransformer: added %T for %s current object", node, addr)
				}

				if t.ConcreteDeposed != nil {
					for dk := range is.Deposed {
						abstract := NewNodeAbstractResourceInstance(addr)
						node := t.ConcreteDeposed(abstract, dk)
						g.Add(node)
						log.Printf("[TRACE] StateTransformer: added %T for %s deposed object %s", node, addr, dk)
					}
				}
			}
		}
	}

	return nil
}