get enum directly from expander

Author: dsa0x

internal/genconfig/generate_config.go

@@ -138,18 +138,12 @@ type ResourceListElement struct {
 	Config cty.Value
 
 	Identity cty.Value
-}
-
-// UniqueAddr is a unique address for each resource instance
-type UniqueAddr struct {
-	// Addr is the address of the resource instance.
-	Addr addrs.AbsResourceInstance
 
-	// ExpansionEnum is the enumeration of the address during expansion.
+	// ExpansionEnum is a unique enumeration of the list resource address relative to its expanded siblings.
 	ExpansionEnum int
 }
 
-func GenerateListResourceContents(uniqAddr UniqueAddr,
+func GenerateListResourceContents(addr addrs.AbsResourceInstance,
 	schema *configschema.Block,
 	idSchema *configschema.Object,
 	pc addrs.LocalProviderConfig,
@@ -159,8 +153,6 @@ func GenerateListResourceContents(uniqAddr UniqueAddr,
 	var diags tfdiags.Diagnostics
 	ret := ImportGroup{}
 
-	addr := uniqAddr.Addr
-
 	for idx, res := range resources {
 		// Generate a unique resource name for each instance in the list.
 		resAddr := addrs.AbsResourceInstance{
@@ -178,7 +170,7 @@ func GenerateListResourceContents(uniqAddr UniqueAddr,
 		if addr.Resource.Key == addrs.NoKey {
 			resAddr.Resource.Resource.Name = fmt.Sprintf("%s_%d", addr.Resource.Resource.Name, idx)
 		} else {
-			resAddr.Resource.Resource.Name = fmt.Sprintf("%s_%d_%d", addr.Resource.Resource.Name, uniqAddr.ExpansionEnum, idx)
+			resAddr.Resource.Resource.Name = fmt.Sprintf("%s_%d_%d", addr.Resource.Resource.Name, res.ExpansionEnum, idx)
 		}
 
 		content, gDiags := GenerateResourceContents(resAddr, schema, pc, res.Config, true)

internal/genconfig/generate_config_test.go

@@ -983,7 +983,7 @@ func TestGenerateResourceAndIDContents(t *testing.T) {
 	}
 
 	// Generate content
-	content, diags := GenerateListResourceContents(UniqueAddr{Addr: instAddr1, ExpansionEnum: 0}, schema, idSchema, pc, listElements)
+	content, diags := GenerateListResourceContents(instAddr1, schema, idSchema, pc, listElements)
 	// Check for diagnostics
 	if diags.HasErrors() {
 		t.Fatalf("unexpected diagnostics: %s", diags.Err())

internal/instances/expander.go

@@ -5,6 +5,7 @@ package instances
 
 import (
 	"fmt"
+	"slices"
 	"sort"
 	"sync"
 
@@ -338,6 +339,16 @@ func (e *Expander) ExpandResource(resourceAddr addrs.AbsResource) []addrs.AbsRes
 	return ret
 }
 
+// ResourceExpansionEnum returns the expansion enum for the given resource instance address
+// within the sorted list of resource instances belonging to the same resource config within
+// the same module instance.
+func (e *Expander) ResourceExpansionEnum(resourceAddr addrs.AbsResourceInstance) int {
+	res := e.ExpandResource(resourceAddr.ContainingResource())
+	return slices.IndexFunc(res, func(addr addrs.AbsResourceInstance) bool {
+		return addr.Equal(resourceAddr)
+	})
+}
+
 // UnknownResourceInstances finds a set of patterns that collectively cover
 // all of the possible resource instance addresses that could appear for the
 // given static resource once all of the intermediate module expansions are

internal/terraform/node_resource_abstract_instance.go

@@ -52,12 +52,6 @@ type NodeAbstractResourceInstance struct {
 
 	// override is set by the graph itself, just before this node executes.
 	override *configs.Override
-
-	// expansionEnum tracks the index of the resource instance within the resource.
-	// While the index is an enumerated value, it does not represent the evaluation order
-	// of the instances. It is currently used to generate unique hcl identifiers, because
-	// for_each keys are not guaranteed to be valid identifiers.
-	expansionEnum int
 }
 
 // NewNodeAbstractResourceInstance creates an abstract resource instance graph

internal/terraform/node_resource_plan_instance.go

@@ -938,6 +938,9 @@ func (n *NodePlannableResourceInstance) generateHCLListResourceDef(ctx EvalConte
 
 	var listElements []genconfig.ResourceListElement
 
+	expander := ctx.InstanceExpander()
+	enum := expander.ResourceExpansionEnum(addr)
+
 	iter := state.ElementIterator()
 	for iter.Next() {
 		_, val := iter.Element()
@@ -955,10 +958,10 @@ func (n *NodePlannableResourceInstance) generateHCLListResourceDef(ctx EvalConte
 		}
 		idVal := val.GetAttr("identity")
 
-		listElements = append(listElements, genconfig.ResourceListElement{Config: config, Identity: idVal})
+		listElements = append(listElements, genconfig.ResourceListElement{Config: config, Identity: idVal, ExpansionEnum: enum})
 	}
 
-	return genconfig.GenerateListResourceContents(genconfig.UniqueAddr{Addr: addr, ExpansionEnum: n.expansionEnum}, schema.Body, schema.Identity, providerAddr, listElements)
+	return genconfig.GenerateListResourceContents(addr, schema.Body, schema.Identity, providerAddr, listElements)
 }
 
 func (n *NodePlannableResourceInstance) generateResourceConfig(ctx EvalContext, state cty.Value) (cty.Value, tfdiags.Diagnostics) {

internal/terraform/transform_resource_count.go

@@ -24,10 +24,9 @@ type ResourceCountTransformer struct {
 }
 
 func (t *ResourceCountTransformer) Transform(g *Graph) error {
-	for idx, addr := range t.InstanceAddrs {
+	for _, addr := range t.InstanceAddrs {
 		abstract := NewNodeAbstractResourceInstance(addr)
 		abstract.Schema = t.Schema
-		abstract.expansionEnum = idx
 		var node dag.Vertex = abstract
 		if f := t.Concrete; f != nil {
 			node = f(abstract)