Index resolution and origin membership

internal/engine/load_metadata.go

@@ -157,15 +157,12 @@ func originRepresentedByChange(path Path, origin Origin, change Change) bool {
 	// A subtree replacement already records its descendants' contributions.
 	// Their coordinates differ from the container's, but their sources must be
 	// covered by the operation; matching only the precedence role is insufficient.
+	recordedSources := make(map[string]struct{}, len(change.Origin.Locations))
+	for _, recorded := range change.Origin.Locations {
+		recordedSources[recorded.SourceID] = struct{}{}
+	}
 	for _, location := range origin.Locations {
-		found := false
-		for _, recorded := range change.Origin.Locations {
-			if location.SourceID == recorded.SourceID {
-				found = true
-				break
-			}
-		}
-		if !found {
+		if _, found := recordedSources[location.SourceID]; !found {
 			return false
 		}
 	}
@@ -189,15 +186,12 @@ func originContainedBy(candidate, container Origin) bool {
 	if candidate.Layer != container.Layer || candidate.Operation != container.Operation {
 		return false
 	}
+	availableLocations := make(map[Location]struct{}, len(container.Locations))
+	for _, location := range container.Locations {
+		availableLocations[location] = struct{}{}
+	}
 	for _, location := range candidate.Locations {
-		found := false
-		for _, available := range container.Locations {
-			if location == available {
-				found = true
-				break
-			}
-		}
-		if !found {
+		if _, found := availableLocations[location]; !found {
 			return false
 		}
 	}