From f159c2285ff3d8812c65a2c59bb2868df975c395 Mon Sep 17 00:00:00 2001
From: Linda Oraegbunam <108290852+obielin@users.noreply.github.com>
Date: Fri, 29 May 2026 21:25:53 +0100
Subject: [PATCH 1/2] fix: detect duplicate feature view/data source names
 early in parse_repo (#6417)

Moves duplicate feature view name and data source name detection into parse_repo() before FeatureStore initialization. This prevents flaky test failures caused by slow atexit handlers (Dask, PySpark) blocking process exit when the error is raised late.
---
 sdk/python/feast/repo_operations.py | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/sdk/python/feast/repo_operations.py b/sdk/python/feast/repo_operations.py
index 28fe86602ad..ec1a218bd02 100644
--- a/sdk/python/feast/repo_operations.py
+++ b/sdk/python/feast/repo_operations.py
@@ -28,6 +28,7 @@
 from feast.infra.registry.base_registry import BaseRegistry
 from feast.infra.registry.registry import FEAST_OBJECT_TYPES, FeastObjectType, Registry
 from feast.names import adjectives, animals
+from feast.errors import ConflictingFeatureViewNames, DataSourceRepeatNamesException
 from feast.on_demand_feature_view import OnDemandFeatureView
 from feast.permissions.permission import Permission
 from feast.project import Project
@@ -219,6 +220,33 @@ def parse_repo(repo_root: Path) -> RepoContents:
             elif isinstance(obj, Project) and not any((obj is p) for p in res.projects):
                 res.projects.append(obj)
 
+    # Early duplicate detection: validate feature view names are case-insensitively unique
+    # This runs before FeatureStore initialization to avoid slow cleanup on error
+    fv_names_seen = {}
+    all_feature_views = (
+        res.feature_views + res.stream_feature_views + res.on_demand_feature_views
+    )
+    for fv in all_feature_views:
+        lower_name = fv.name.lower()
+        if lower_name in fv_names_seen:
+            existing_fv = fv_names_seen[lower_name]
+            raise ConflictingFeatureViewNames(
+                fv.name,
+                existing_type=type(existing_fv).__name__,
+                new_type=type(fv).__name__,
+            )
+        fv_names_seen[lower_name] = fv
+
+    # Early duplicate detection: validate data source names are case-insensitively unique
+    ds_names_seen = {}
+    for ds in res.data_sources:
+        if ds.name is None:
+            continue
+        lower_name = ds.name.lower()
+        if lower_name in ds_names_seen:
+            raise DataSourceRepeatNamesException(ds.name)
+        ds_names_seen[lower_name] = ds
+
     res.entities.append(DUMMY_ENTITY)
     return res
 

From bbcf25aaf6c94777d276aae5c95da1ef2cbd2d75 Mon Sep 17 00:00:00 2001
From: Linda Oraegbunam <108290852+obielin@users.noreply.github.com>
Date: Fri, 29 May 2026 21:32:17 +0100
Subject: [PATCH 2/2] fix: add FeastError handler in CLI plan/apply commands
 (#6417)

Add sys import and FeastError catch blocks to plan_command and apply_total_command in cli.py. This ensures clean error output and immediate exit (code 1) when validation errors like ConflictingFeatureViewNames are raised, preventing unhandled traceback and slow process exit.
---
 sdk/python/feast/cli/cli.py | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/sdk/python/feast/cli/cli.py b/sdk/python/feast/cli/cli.py
index 886c91f69ae..1e03c97e3a4 100644
--- a/sdk/python/feast/cli/cli.py
+++ b/sdk/python/feast/cli/cli.py
@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import json
+import sys
 import logging
 from datetime import datetime
 from importlib.metadata import version as importlib_version
@@ -49,7 +50,7 @@
 from feast.cli.ui import ui
 from feast.cli.validation_references import validation_references_cmd
 from feast.constants import FEAST_FS_YAML_FILE_PATH_ENV_NAME
-from feast.errors import FeastProviderLoginError
+from feast.errors import FeastError, FeastProviderLoginError
 from feast.repo_config import load_repo_config
 from feast.repo_operations import (
     apply_total,
@@ -258,6 +259,9 @@ def plan_command(
         plan(repo_config, repo, skip_source_validation, skip_feature_view_validation)
     except FeastProviderLoginError as e:
         print(str(e))
+    except FeastError as e:
+        print(str(e))
+        sys.exit(1)
 
 
 @cli.command("apply", cls=NoOptionDefaultFormat)
@@ -316,6 +320,9 @@ def apply_total_command(
         )
     except FeastProviderLoginError as e:
         print(str(e))
+    except FeastError as e:
+        print(str(e))
+        sys.exit(1)
 
 
 @cli.command("teardown", cls=NoOptionDefaultFormat)