fix: remove dummy data fallback in experiments_api.py render endpoint

backend/app/modules/platform/experiments_api.py

@@ -433,7 +433,7 @@ async def render_figure_endpoint(experiment_id: str, req: RenderFigureRequest):
         artifact = generate_figure(
             experiment_id=experiment_id,
             user_spec=user_spec,
-            data_override=data_override or [{'_': 1}],
+            data_override=data_override,
         )
         return artifact
     except ValueError as exc:

backend/tests/test_pr_10_experiments_render.py

@@ -0,0 +1,37 @@
+"""
+Test that the experiments render figure endpoint does not inject dummy data
+when data_override is None.
+"""
+
+import unittest
+import sys
+import os
+
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))
+
+
+class TestExperimentsRenderDummyData(unittest.TestCase):
+    """Tests for the render figure endpoint data_override handling."""
+
+    def test_data_override_none_not_replaced_with_dummy(self):
+        """data_override should not be replaced with dummy fallback."""
+        from app.modules.platform import experiments_api
+        import inspect
+        source = inspect.getsource(experiments_api)
+        self.assertNotIn(
+            "data_override or [{"'_'": 1}]",
+            source,
+            "Dummy data fallback should not be present"
+        )
+
+    def test_data_override_passed_through_directly(self):
+        """generate_figure should receive data_override as-is."""
+        from app.modules.platform import experiments_api
+        import inspect
+        source = inspect.getsource(experiments_api)
+        direct_passes = source.count("data_override=data_override,")
+        self.assertGreaterEqual(direct_passes, 3)
+
+
+if __name__ == "__main__":
+    unittest.main()