Dashboard: Wait for Inputs, Fix Python 3.14

src/python/impactx/dashboard/start.py

@@ -6,6 +6,8 @@
 License: BSD-3-Clause-LBNL
 """
 
+import asyncio
+
 from . import server, state
 from .app import application
 from .Input.defaults import DashboardDefaults
@@ -42,6 +44,18 @@ class DashboardApp:
 
     def start(self):
         setup_dashboard()
+
+        # Ensure an event loop exists for Python 3.10+ (required on macOS)
+        # This prevents RuntimeError when server.start() tries to get_event_loop()
+        # In Python 3.10+, get_event_loop() raises RuntimeError if no loop exists
+        # We create and set one if needed
+        try:
+            asyncio.get_event_loop()
+        except RuntimeError:
+            # No event loop exists in this thread, create and set one
+            loop = asyncio.new_event_loop()
+            asyncio.set_event_loop(loop)
+
         server.start()
         return 0
 

tests/python/dashboard/test_python_import.py

@@ -24,6 +24,10 @@ def test_python_import(dashboard):
     """
     dashboard.load_example("testdata/example.py", manual=True)
 
+    # Wait for the dashboard to finish loading the example file
+    # This ensures all UI elements are rendered before we check their values
+    dashboard.sb.wait_for_element_present("#Input_route", timeout=10)
+
     BEAM_PARAMETERS = [
         ("tracking_mode", "Particle Tracking"),
         ("space_charge", "false"),
@@ -72,6 +76,10 @@ def test_python_import(dashboard):
 
     # Check input values
     for element_id, expected_value in DISTRIBUTION_VALUES + LATTICE_CONFIGURATION:
+        # Wait for element to be visible before getting its value
+        # This is important for CI environments where rendering may be slower
+        dashboard.sb.wait_for_element_visible(element_id, timeout=10)
+
         actual_value = float(dashboard.sb.get_value(element_id))
         assert actual_value == pytest.approx(expected_value, **APPROX_TOL), (
             f"{element_id}: expected {expected_value}, got {actual_value}"