From 7a9d542bee595966f6db9b5d30869d16cc0652b0 Mon Sep 17 00:00:00 2001
From: Ladislav Thon <lthon@redhat.com>
Date: Wed, 6 Dec 2023 13:40:30 +0100
Subject: [PATCH] ArC: detect duplicate bean identifiers

---
 .../quarkus/arc/processor/BeanDeployment.java | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/independent-projects/arc/processor/src/main/java/io/quarkus/arc/processor/BeanDeployment.java b/independent-projects/arc/processor/src/main/java/io/quarkus/arc/processor/BeanDeployment.java
index 1ea3ad5b3bf49f..3dff889451ef53 100644
--- a/independent-projects/arc/processor/src/main/java/io/quarkus/arc/processor/BeanDeployment.java
+++ b/independent-projects/arc/processor/src/main/java/io/quarkus/arc/processor/BeanDeployment.java
@@ -1583,6 +1583,29 @@ private void validateBeans(List<Throwable> errors, Consumer<BytecodeTransformer>
                 }
             }
         }
+
+        List<Map.Entry<String, List<BeanInfo>>> duplicateBeanIds = beans.stream()
+                .collect(Collectors.groupingBy(BeanInfo::getIdentifier))
+                .entrySet()
+                .stream()
+                .filter(entry -> entry.getValue().size() > 1)
+                .collect(Collectors.toList());
+        if (!duplicateBeanIds.isEmpty()) {
+            String separator = "====================";
+            StringBuilder error = new StringBuilder("\n")
+                    .append(separator).append(separator).append(separator).append(separator).append("\n")
+                    .append("Multiple beans with the same identifier found!\n")
+                    .append("----------------------------------------------\n")
+                    .append("This is an internal error. Please report a bug and attach the following listing.\n\n");
+            for (Map.Entry<String, List<BeanInfo>> entry : duplicateBeanIds) {
+                error.append(entry.getKey()).append(" -> ").append(entry.getValue().size()).append(" beans:\n");
+                for (BeanInfo bean : entry.getValue()) {
+                    error.append("- ").append(bean).append("\n");
+                }
+            }
+            error.append(separator).append(separator).append(separator).append(separator).append("\n");
+            errors.add(new DeploymentException(error.toString()));
+        }
     }
 
     private void findNamespaces(BeanInfo bean, Set<String> namespaces) {