Include exception message in ErrorAnalysisCard subtitle (facebook#4982)

Summary:

Currently, the subtitle only shows a generic message like "AnalysisNotApplicableStateError encountered while computing ParallelCoordinatesPlot." Show the actual exception message, such as "AnalysisNotApplicableStateError: Experiment has no trials", providing immediate context.

The exception message can now be displayed in the ErrorAnalysisCard subtitle, allowing users to immediately see the reasoning (e.g., why an analysis is not applicable).

Reviewed By: bernardbeckerman

Differential Revision: D94617700

Author: shrutipatel31

ax/analysis/analysis.py

@@ -206,10 +206,21 @@ def error_card_from_analysis_e(
     analysis_name = analysis_e.analysis.__class__.__name__
     exception_name = analysis_e.exception.__class__.__name__
 
+    # Include the exception message in the subtitle if available, so users can
+    # see the reasoning in the error card.
+    subtitle = (
+        f"{exception_name}: {exception_message}"
+        if (exception_message := str(analysis_e.exception))
+        else f"{exception_name} encountered while computing {analysis_name}."
+    )
+
+    tb = analysis_e.tb_str()
+    blob = f"{subtitle}\n\n{tb}" if tb else subtitle
+
     return ErrorAnalysisCard(
         name=analysis_name,
         title=f"{analysis_name} Error",
-        subtitle=f"{exception_name} encountered while computing {analysis_name}.",
+        subtitle=subtitle,
         df=pd.DataFrame(),
-        blob=analysis_e.tb_str() or "",
+        blob=blob,
     )

ax/analysis/tests/test_analysis.py

@@ -0,0 +1,47 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+# pyre-strict
+
+from ax.analysis.analysis import AnalysisE, error_card_from_analysis_e
+from ax.analysis.plotly.parallel_coordinates import ParallelCoordinatesPlot
+from ax.utils.common.testutils import TestCase
+
+
+class AnalysisTest(TestCase):
+    def test_error_card_from_analysis_e_with_message(self) -> None:
+        # Setup: create an AnalysisE with an exception that has a message.
+        analysis_e = AnalysisE(
+            message="test",
+            exception=ValueError("something went wrong"),
+            analysis=ParallelCoordinatesPlot(),
+        )
+
+        # Execute: generate the error card.
+        card = error_card_from_analysis_e(analysis_e)
+
+        # Assert: subtitle and blob contain the exception message.
+        self.assertEqual(card.name, "ParallelCoordinatesPlot")
+        self.assertEqual(card.title, "ParallelCoordinatesPlot Error")
+        self.assertEqual(card.subtitle, "ValueError: something went wrong")
+        self.assertIn("ValueError: something went wrong", card.blob)
+
+    def test_error_card_from_analysis_e_without_message(self) -> None:
+        # Setup: create an AnalysisE with an exception that has no message.
+        analysis_e = AnalysisE(
+            message="test",
+            exception=ValueError(),
+            analysis=ParallelCoordinatesPlot(),
+        )
+
+        # Execute: generate the error card.
+        card = error_card_from_analysis_e(analysis_e)
+
+        # Assert: subtitle and blob use the fallback text.
+        expected = "ValueError encountered while computing ParallelCoordinatesPlot."
+        self.assertEqual(card.name, "ParallelCoordinatesPlot")
+        self.assertEqual(card.title, "ParallelCoordinatesPlot Error")
+        self.assertEqual(card.subtitle, expected)
+        self.assertIn(expected, card.blob)

ax/api/tests/test_client.py

@@ -23,7 +23,6 @@
 from ax.api.protocols.metric import IMetric
 from ax.api.protocols.runner import IRunner
 from ax.api.types import TParameterization
-from ax.core.analysis_card import AnalysisCard
 from ax.core.data import Data
 from ax.core.experiment import Experiment
 from ax.core.map_metric import MapMetric
@@ -1278,14 +1277,17 @@ def test_compute_analyses(self) -> None:
         self.assertEqual(len(cards), 1)
         self.assertEqual(cards[0].name, "ParallelCoordinatesPlot")
         self.assertEqual(cards[0].title, "ParallelCoordinatesPlot Error")
-        self.assertEqual(
+        self.assertIn(
+            "AnalysisNotApplicableStateError",
+            cards[0].subtitle,
+        )
+        self.assertIn(
+            "Experiment has no trials",
             cards[0].subtitle,
-            "AnalysisNotApplicableStateError encountered while computing "
-            "ParallelCoordinatesPlot.",
         )
         self.assertIn(
             "Experiment has no trials",
-            assert_is_instance(cards[0], AnalysisCard).blob,
+            cards[0].blob,
         )
 
         for trial_index, _ in client.get_next_trials(max_trials=1).items():