From 7232a13157dbec832993e38bf7d9baac6f3d7671 Mon Sep 17 00:00:00 2001
From: helloJetBase-tech <178346048+marktech0813@users.noreply.github.com>
Date: Mon, 10 Nov 2025 16:45:14 +0200
Subject: [PATCH] Fix error: Unusable type signature for overload of
 graphql.schema.SchemaTraverser::depthFirst #4147
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I found the problematic overload in SchemaTraverser and updated its public API to accept the correct visitor type, ensuring it’s usable outside the class.

This removes the unusable public signature that referenced the private TraverserDelegateVisitor type.
All existing internal calls (which pass new TraverserDelegateVisitor(...)) still work because that class implements TraverserVisitor<GraphQLSchemaElement>.

Summary:
- Changed SchemaTraverser.depthFirst(Traverser, TraverserDelegateVisitor, ...) to use TraverserVisitor<GraphQLSchemaElement> instead, and adjusted the helper accordingly.
- Public API is now usable by callers without referencing a private inner class; no behavior change for existing internal usage.
---
 src/main/java/graphql/schema/SchemaTraverser.java | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/main/java/graphql/schema/SchemaTraverser.java b/src/main/java/graphql/schema/SchemaTraverser.java
index 809904e30c..5322f4b407 100644
--- a/src/main/java/graphql/schema/SchemaTraverser.java
+++ b/src/main/java/graphql/schema/SchemaTraverser.java
@@ -83,9 +83,9 @@ public TraverserResult depthFirst(final GraphQLTypeVisitor graphQLTypeVisitor, C
 
 
     public TraverserResult depthFirst(final Traverser<GraphQLSchemaElement> traverser,
-                                      final TraverserDelegateVisitor traverserDelegateVisitor,
+                                      final TraverserVisitor<GraphQLSchemaElement> traverserVisitor,
                                       Collection<? extends GraphQLSchemaElement> roots) {
-        return doTraverse(traverser, roots, traverserDelegateVisitor);
+        return doTraverse(traverser, roots, traverserVisitor);
     }
 
     private Traverser<GraphQLSchemaElement> initTraverser() {
@@ -94,8 +94,8 @@ private Traverser<GraphQLSchemaElement> initTraverser() {
 
     private TraverserResult doTraverse(Traverser<GraphQLSchemaElement> traverser,
                                        Collection<? extends GraphQLSchemaElement> roots,
-                                       TraverserDelegateVisitor traverserDelegateVisitor) {
-        return traverser.traverse(roots, traverserDelegateVisitor);
+                                       TraverserVisitor<GraphQLSchemaElement> traverserVisitor) {
+        return traverser.traverse(roots, traverserVisitor);
     }
 
     private static class TraverserDelegateVisitor implements TraverserVisitor<GraphQLSchemaElement> {