Fix Date Parsing Issue in Arrow Parser for CSV Files (#59904)

pandas/core/series.py

@@ -3223,6 +3223,13 @@ def combine_first(self, other) -> Series:
         """
         from pandas.core.reshape.concat import concat
 
+        def replace_none_with_nan(series):
+            series.fillna(value=np.nan, inplace=True)
+
+        """Apply the function to both Series"""
+        replace_none_with_nan(self)
+        replace_none_with_nan(other)
+
         if self.dtype == other.dtype:
             if self.index.equals(other.index):
                 return self.mask(self.isna(), other)

pandas/io/parsers/arrow_parser_wrapper.py

@@ -274,6 +274,14 @@ def read(self) -> DataFrame:
 
         dtype_backend = self.kwds["dtype_backend"]
 
+        # Handle missing date values by checking for timestamp columns
+        for i, field in enumerate(table.schema):
+            if pa.types.is_timestamp(field.type):
+                column = table.column(i).to_pandas()
+                column.fillna(pd.NaT, inplace=True)
+
+                table = table.set_column(i, field.name, pa.array(column))
+
         # Convert all pa.null() cols -> float64 (non nullable)
         # else Int64 (nullable case, see below)
         if dtype_backend is lib.no_default: