test(jumpstart): cover EU Sovereign Cloud model setup

Exercise the reported DeepSeek setup against live public metadata. Document why draft-model bucket selection can return no Neo bucket.

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X-AI-Prompt: Can you add integration tests for the screenshot error and address the review comments?
X-AI-Tool: claude-code

Author: evakravi

sagemaker-core/src/sagemaker/core/jumpstart/utils.py

@@ -1699,7 +1699,12 @@ def _add_model_access_configs_to_model_data_sources(
 
 
 def get_draft_model_content_bucket(provider: Dict, region: str) -> Optional[str]:
-    """Returns the correct content bucket for a 1p draft model."""
+    """Returns the draft-model bucket selected by provider metadata, if available.
+
+    Returns:
+        Optional[str]: A JumpStart bucket for JumpStart metadata, or a Neo bucket for
+            Neo and legacy metadata. Returns ``None`` when the selected Neo bucket is absent.
+    """
     provider_name = provider.get("name", "") if provider else ""
     if provider_name == "JumpStart":
         classification = provider.get("classification", "ungated")

sagemaker-core/tests/integ/jumpstart/test_bucket_utils.py

@@ -0,0 +1,56 @@
+# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"). You
+# may not use this file except in compliance with the License. A copy of
+# the License is located at
+#
+#     http://aws.amazon.com/apache2.0/
+#
+# or in the "license" file accompanying this file. This file is
+# distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF
+# ANY KIND, either express or implied. See the License for the specific
+# language governing permissions and limitations under the License.
+"""Regression tests for JumpStart metadata setup in EU Sovereign Cloud."""
+from __future__ import absolute_import
+
+import boto3
+import pytest
+from botocore import UNSIGNED
+from botocore.config import Config
+
+from sagemaker.core.jumpstart.accessors import JumpStartModelsAccessor
+from sagemaker.core.jumpstart.factory.utils import _add_additional_model_data_sources_to_kwargs
+from sagemaker.core.jumpstart.types import JumpStartModelInitKwargs
+
+EUSC_REGION = "eusc-de-east-1"
+DEEPSEEK_MODEL_ID = "deepseek-llm-r1-distill-llama-8b"
+
+
+@pytest.fixture
+def model_specs():
+    s3_client = boto3.client(
+        "s3",
+        region_name=EUSC_REGION,
+        config=Config(signature_version=UNSIGNED),
+    )
+    JumpStartModelsAccessor.reset_cache({"s3_client": s3_client}, region=EUSC_REGION)
+    return JumpStartModelsAccessor.get_model_specs(
+        region=EUSC_REGION,
+        model_id=DEEPSEEK_MODEL_ID,
+        version="*",
+    )
+
+
+@pytest.mark.serial
+def test_deepseek_without_speculative_metadata_does_not_require_neo(model_specs):
+    assert model_specs.get_speculative_decoding_s3_data_sources() == []
+    kwargs = JumpStartModelInitKwargs(
+        model_id=DEEPSEEK_MODEL_ID,
+        model_version=model_specs.version,
+        region=EUSC_REGION,
+    )
+    kwargs.specs = model_specs
+
+    result = _add_additional_model_data_sources_to_kwargs(kwargs)
+
+    assert result.additional_model_data_sources is None