DOC: Validate versions.json before building docs pandas-dev#61573

Author: iabhi4

web/pandas_web.py

@@ -397,6 +397,16 @@ def get_context(config_fname: str, **kwargs):
     context["source_path"] = os.path.dirname(config_fname)
     context.update(kwargs)
 
+    # Validate versions.json
+    versions_path = os.path.join(context["source_path"], "versions.json")
+    if os.path.exists(versions_path):
+        try:
+            with open(versions_path, encoding="utf-8") as f:
+                json.load(f)
+        except json.JSONDecodeError as e:
+            sys.stderr.write(f"\n[ERROR] Invalid JSON in {versions_path}:\n{e}\n")
+            sys.exit(1)
+
     preprocessors = (
         get_callable(context_prep)
         for context_prep in context["main"]["context_preprocessors"]