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pkg/hcl_interpreter/accessor.go

@@ -97,17 +97,19 @@ func traversalToAccessor(traversal hcl.Traversal) (accessor, error) {
 	return parts, nil
 }
 
+// toLocalName tries to convert the accessor to a local name starting from the
+// front.  As soon as a non-string part is encountered, we stop and return the
+// trailing accessor as well.
 func (a accessor) toLocalName() (LocalName, accessor) {
 	name := make(LocalName, 0)
 	trailing := make(accessor, len(a))
 	copy(trailing, a)
-	numeric := false
-	for !numeric && len(trailing) > 0 {
+	for len(trailing) > 0 {
 		if str, ok := trailing[0].(string); ok {
 			name = append(name, str)
 			trailing = trailing[1:]
 		} else {
-			numeric = true
+			break
 		}
 	}
 	return name, trailing

pkg/hcl_interpreter/names.go

@@ -102,11 +102,11 @@ func (name LocalName) Equals(other LocalName) bool {
 }
 
 func (name LocalName) ToAccessor() accessor {
-    accessor := make(accessor, len(name))
-    for i := range name {
-        accessor[i] = name[i]
-    }
-    return accessor
+	accessor := make(accessor, len(name))
+	for i := range name {
+		accessor[i] = name[i]
+	}
+	return accessor
 }
 
 type FullName struct {
@@ -225,14 +225,14 @@ func (name FullName) AsResourceName() (*FullName, LocalName) {
 	return nil, nil
 }
 
-// TODO: Refactor to TraversalToName?
-// TODO: Return trailing part
+// TraversalToLocalName returns the leading LocalName (strictly-string) part of
+// a traversal as well as the trailing part (string-or-int).
 func TraversalToLocalName(traversal hcl.Traversal) (LocalName, accessor, error) {
+	// Just delegate the conversion to the accessor.
 	accessor, err := traversalToAccessor(traversal)
 	if err != nil {
 		return nil, nil, err
 	}
-
 	name, trailing := accessor.toLocalName()
 	return name, trailing, nil
 }

pkg/hcl_interpreter/phantom_attrs.go

@@ -70,16 +70,23 @@ func (pa *phantomAttrs) analyze(name FullName, term Term) {
 			if asResourceName, resourceTrailing := full.AsResourceName(); asResourceName != nil {
 				attrs := map[string]struct{}{}
 
-    			trailingAccessor := resourceTrailing.ToAccessor()
-    			trailingAccessor = append(trailingAccessor, localTrailing...)
-    			if pa.isMultiResource(*asResourceName) && len(trailingAccessor) > 0 {
-        			trailingAccessor = trailingAccessor[1:]
-    			}
-    			trailing, _ := trailingAccessor.toLocalName()
-				if len(trailing) > 0 {
+				// Construct the trailing part from the resourceTrailing
+				// and localTrailing parts defined above.
+				trailingAccessor := resourceTrailing.ToAccessor()
+				trailingAccessor = append(trailingAccessor, localTrailing...)
+
+				// We need to strip one element from the index if this is a
+				// multi-resource to drop the index or key.
+				if pa.isMultiResource(*asResourceName) && len(trailingAccessor) > 0 {
+					trailingAccessor = trailingAccessor[1:]
+				}
+
+				// Store the trailing part that was accessed in attrs.
+				if trailing, _ := trailingAccessor.toLocalName(); len(trailing) > 0 {
 					attrs[LocalNameToString(trailing)] = struct{}{}
 				}
 
+				// Store the other attrs.
 				for _, attr := range exprAttrs {
 					attrs[LocalNameToString(attr)] = struct{}{}
 				}