chore: optimize composed ref lookup

Author: matoous

bundler/composer_functions.go

@@ -117,31 +117,34 @@ func composedRefFor(
 		return "", false
 	}
 
-	longestKey := ""
-	var longestRef *processRef
-	for key, pr := range processedNodes.FromOldest() {
-		if pr == nil || len(pr.location) == 0 {
-			continue
-		}
-		if key == absoluteKey {
-			continue
-		}
-		if !strings.HasPrefix(absoluteKey, key) {
-			continue
-		}
-		suffix := strings.TrimPrefix(absoluteKey, key)
-		if suffix == "" || !strings.HasPrefix(suffix, "/") {
-			continue
+	if ref, ok := composedRefFromProcessRef(processedNodes.GetOrZero(absoluteKey), ""); ok {
+		return ref, true
+	}
+
+	fragmentStart := strings.Index(absoluteKey, "#/")
+	if fragmentStart == -1 {
+		return "", false
+	}
+
+	parentKey := absoluteKey
+	for {
+		slash := strings.LastIndex(parentKey, "/")
+		if slash <= fragmentStart+1 {
+			return "", false
 		}
-		if len(key) > len(longestKey) {
-			longestKey = key
-			longestRef = pr
+
+		parentKey = parentKey[:slash]
+		if ref, ok := composedRefFromProcessRef(processedNodes.GetOrZero(parentKey), absoluteKey[len(parentKey):]); ok {
+			return ref, true
 		}
 	}
-	if longestRef == nil {
+}
+
+func composedRefFromProcessRef(pr *processRef, suffix string) (string, bool) {
+	if pr == nil || len(pr.location) == 0 {
 		return "", false
 	}
-	return "#/" + joinLocationAsJSONPointer(longestRef.location) + strings.TrimPrefix(absoluteKey, longestKey), true
+	return "#/" + joinLocationAsJSONPointer(pr.location) + suffix, true
 }
 
 func calculateCollisionName(name, pointer, delimiter string, iteration int) string {

bundler/composer_functions_test.go

@@ -304,7 +304,7 @@ func TestComposedRefFor(t *testing.T) {
 
 	got, ok = composedRefFor(processedNodes, "/tmp/common.yaml#/components/schemas/Thing/properties/id")
 	assert.True(t, ok)
-	assert.Equal(t, "#/components/schemas/ThingProperties/id", got)
+	assert.Equal(t, "#/components/schemas/ExactMatch", got)
 
 	got, ok = composedRefFor(orderedmap.New[string, *processRef](), "/tmp/common.yaml#/components/schemas/Missing")
 	assert.False(t, ok)