From 97b669b4802c86ee09719120591523b54bde0950 Mon Sep 17 00:00:00 2001
From: Avinash Kumar Deepak <avinash8655279@gmail.com>
Date: Thu, 19 Feb 2026 19:48:51 +0530
Subject: [PATCH 1/2] fix: error on duplicate node labels in mkconcore and
 validate

---
 concore_cli/commands/validate.py | 9 ++++++++-
 mkconcore.py                     | 6 ++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/concore_cli/commands/validate.py b/concore_cli/commands/validate.py
index 7cacab9..6adf5fc 100644
--- a/concore_cli/commands/validate.py
+++ b/concore_cli/commands/validate.py
@@ -117,7 +117,14 @@ def finalize():
                     warnings.append(f"Node {node_id} has no label")
             except Exception as e:
                 warnings.append(f"Error parsing node: {str(e)}")
-        
+
+        # duplicate labels cause silent corruption in mkconcore.py (#384)
+        seen = set()
+        for label in node_labels:
+            if label in seen:
+                errors.append(f"Duplicate node label: '{label}'")
+            seen.add(label)
+
         node_ids = {node.get('id') for node in nodes if node.get('id')}
         for edge in edges:
             source = edge.get('source')
diff --git a/mkconcore.py b/mkconcore.py
index 0a11948..da935f8 100644
--- a/mkconcore.py
+++ b/mkconcore.py
@@ -307,6 +307,12 @@ def cleanup_script_files():
     except (IndexError, AttributeError):
         logging.debug('A node with no valid properties encountered and ignored')
 
+label_values = list(nodes_dict.values())
+duplicates = {label for label in label_values if label_values.count(label) > 1}
+if duplicates:
+    logging.error(f"Duplicate node labels found: {sorted(duplicates)}")
+    quit()
+
 for edge in edges_text:
     try:
         data = edge.find('data', recursive=False)

From 4ebae6cde5ab4e86cd0cfb83c0a598dad04fc20d Mon Sep 17 00:00:00 2001
From: Avinash Kumar Deepak <avinash8655279@gmail.com>
Date: Fri, 20 Feb 2026 11:47:06 +0530
Subject: [PATCH 2/2] remove issue ref from inline comment

---
 concore_cli/commands/validate.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/concore_cli/commands/validate.py b/concore_cli/commands/validate.py
index 6adf5fc..d9a39dd 100644
--- a/concore_cli/commands/validate.py
+++ b/concore_cli/commands/validate.py
@@ -118,7 +118,7 @@ def finalize():
             except Exception as e:
                 warnings.append(f"Error parsing node: {str(e)}")
 
-        # duplicate labels cause silent corruption in mkconcore.py (#384)
+        # duplicate labels cause silent corruption in mkconcore.py
         seen = set()
         for label in node_labels:
             if label in seen: