Add converter parameter to _fetch_all_rows and _as_*_from_api methods

Allow custom type converter to be passed through the API fallback
chain. Defaults to DefaultTypeConverter for backward compatibility.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: laughingman7743

pyathena/arrow/result_set.py

@@ -348,15 +348,19 @@ def _as_arrow(self) -> "Table":
             table = self._read_csv()
         return table
 
-    def _as_arrow_from_api(self) -> "Table":
+    def _as_arrow_from_api(self, converter: Optional[Converter] = None) -> "Table":
         """Build an Arrow Table from GetQueryResults API.
 
         Used as a fallback when ``output_location`` is not available
         (e.g. managed query result storage).
+
+        Args:
+            converter: Type converter for result values. Defaults to
+                ``DefaultTypeConverter`` if not specified.
         """
         import pyarrow as pa
 
-        rows = self._fetch_all_rows()
+        rows = self._fetch_all_rows(converter)
         if not rows:
             return pa.Table.from_pydict({})
         description = self.description if self.description else []

pyathena/pandas/result_set.py

@@ -681,15 +681,19 @@ def _as_pandas(self) -> Union["TextFileReader", "DataFrame"]:
             df = self._read_csv()
         return df
 
-    def _as_pandas_from_api(self) -> "DataFrame":
+    def _as_pandas_from_api(self, converter: Optional[Converter] = None) -> "DataFrame":
         """Build a DataFrame from GetQueryResults API.
 
         Used as a fallback when ``output_location`` is not available
         (e.g. managed query result storage).
+
+        Args:
+            converter: Type converter for result values. Defaults to
+                ``DefaultTypeConverter`` if not specified.
         """
         import pandas as pd
 
-        rows = self._fetch_all_rows()
+        rows = self._fetch_all_rows(converter)
         if not rows:
             return pd.DataFrame()
         description = self.description if self.description else []

pyathena/polars/result_set.py

@@ -542,15 +542,19 @@ def _as_polars(self) -> "pl.DataFrame":
             df = self._read_csv()
         return df
 
-    def _as_polars_from_api(self) -> "pl.DataFrame":
+    def _as_polars_from_api(self, converter: Optional[Converter] = None) -> "pl.DataFrame":
         """Build a Polars DataFrame from GetQueryResults API.
 
         Used as a fallback when ``output_location`` is not available
         (e.g. managed query result storage).
+
+        Args:
+            converter: Type converter for result values. Defaults to
+                ``DefaultTypeConverter`` if not specified.
         """
         import polars as pl
 
-        rows = self._fetch_all_rows()
+        rows = self._fetch_all_rows(converter)
         if not rows:
             return pl.DataFrame()
         description = self.description if self.description else []

pyathena/result_set.py

@@ -497,18 +497,23 @@ def _is_first_row_column_labels(self, rows: List[Dict[str, Any]]) -> bool:
 
     def _fetch_all_rows(
         self,
+        converter: Optional[Converter] = None,
     ) -> List[Tuple[Optional[Any], ...]]:
         """Fetch all rows via GetQueryResults API with type conversion.
 
         Paginates through all results from the beginning using MaxResults=1000.
-        Uses ``DefaultTypeConverter`` for string-to-Python type conversion,
-        ensuring consistent behavior regardless of subclass converter
-        (e.g. Pandas/Arrow converters only handle a subset of types).
+        Defaults to ``DefaultTypeConverter`` for string-to-Python type conversion,
+        because subclass converters (e.g. Pandas/Arrow) are designed for S3 file
+        reading and may not handle API result strings.
 
         This method is intended for use by subclass result sets that need to
         fall back to the API when S3 output is not available (e.g., managed
         query result storage).
 
+        Args:
+            converter: Type converter for result values. Defaults to
+                ``DefaultTypeConverter`` if not specified.
+
         Returns:
             List of converted row tuples.
         """
@@ -521,7 +526,7 @@ def _fetch_all_rows(
             "This may be slow for large result sets."
         )
 
-        converter = DefaultTypeConverter()
+        converter = converter or DefaultTypeConverter()
         all_rows: List[Tuple[Optional[Any], ...]] = []
         next_token: Optional[str] = None