Address review comments

Author: Balaji Veeramani

src/sagemaker/deserializers.py

@@ -81,15 +81,15 @@ def deserialize(self, data, content_type):
         """Deserialize data from an inference endpoint into a list of lists.
 
         Args:
-            data (object): Data to be deserialized.
+            data (botocore.response.StreamingBody): Data to be deserialized.
             content_type (str): The MIME type of the data.
 
         Returns:
             list: The data deserialized into a list of lists representing the
                 contents of a CSV file.
         """
         try:
-            string = data.read().decode(self.encoding)
-            return list(csv.reader(string.splitlines()))
+            decoded_string = data.read().decode(self.encoding)
+            return list(csv.reader(decoded_string.splitlines()))
         finally:
             data.close()

tests/unit/sagemaker/test_deserializers.py

@@ -14,6 +14,8 @@
 
 import io
 
+import pytest
+
 from sagemaker.deserializers import BytesDeserializer, CSVDeserializer
 
 
@@ -25,25 +27,26 @@ def test_bytes_deserializer():
     assert result == b"[1, 2, 3]"
 
 
-def test_csv_deserializer_single_element():
-    deserializer = CSVDeserializer()
+@pytest.fixture
+def csv_deserializer():
+    return CSVDeserializer()
 
-    result = deserializer.deserialize(io.BytesIO(b"1"), "text/csv")
 
+def test_csv_deserializer_single_element(csv_deserializer):
+    result = csv_deserializer.deserialize(io.BytesIO(b"1"), "text/csv")
     assert result == [["1"]]
 
 
-def test_csv_deserializer_array():
-    deserializer = CSVDeserializer()
-
-    result = deserializer.deserialize(io.BytesIO(b"1,2,3"), "text/csv")
-
+def test_csv_deserializer_array(csv_deserializer):
+    result = csv_deserializer.deserialize(io.BytesIO(b"1,2,3"), "text/csv")
     assert result == [["1", "2", "3"]]
 
 
-def test_csv_deserializer_2dimensional():
-    deserializer = CSVDeserializer()
+def test_csv_deserializer_2dimensional(csv_deserializer):
+    result = csv_deserializer.deserialize(io.BytesIO(b"1,2,3\n3,4,5"), "text/csv")
+    assert result == [["1", "2", "3"], ["3", "4", "5"]]
 
-    result = deserializer.deserialize(io.BytesIO(b"1,2,3\n3,4,5"), "text/csv")
 
+def test_csv_deserializer_posix_compliant(csv_deserializer):
+    result = csv_deserializer.deserialize(io.BytesIO(b"1,2,3\n3,4,5\n"), "text/csv")
     assert result == [["1", "2", "3"], ["3", "4", "5"]]