Keep reference algorithms in tests

internal/engine/resolution.go

@@ -370,17 +370,6 @@ type resolutionCoverageIndex struct {
 	depths []int
 }
 
-func newResolutionCoverageIndex(paths []Path) *resolutionCoverageIndex {
-	index := &resolutionCoverageIndex{depths: make([]int, len(paths))}
-	for id, path := range paths {
-		index.depths[id] = len(path.segments)
-		if path.valid() {
-			index.prefix.insert(path.String(), id)
-		}
-	}
-	return index
-}
-
 func newResolutionCoverageIndexFromRecords(records []*resolutionRecord) *resolutionCoverageIndex {
 	index := &resolutionCoverageIndex{depths: make([]int, len(records))}
 	for id, record := range records {
@@ -436,22 +425,6 @@ func pathContains(container, descendant Path) bool {
 	return true
 }
 
-func appendUniqueString(values []string, value string) []string {
-	if !slices.Contains(values, value) {
-		return append(values, value)
-	}
-	return values
-}
-
-func appendUniquePath(paths []Path, path Path) []Path {
-	for _, existing := range paths {
-		if pathSpellingEqual(existing, path) {
-			return paths
-		}
-	}
-	return append(paths, path.clone())
-}
-
 func clonePaths(paths []Path) []Path {
 	if paths == nil {
 		return nil