Creating a more clean implementation

pandas-dev · Jun 15, 2024 · 14e565e · 14e565e
1 parent ffb65d4
commit 14e565e
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Showing 2 changed files with 11 additions and 13 deletions.
diff --git a/pandas/core/arrays/boolean.py b/pandas/core/arrays/boolean.py
@@ -296,8 +296,9 @@ class BooleanArray(BaseMaskedArray):
     Length: 3, dtype: boolean
     """
 
-    _TRUE_VALUES = {True, "True", "TRUE", "true", "1", "1.0"}
-    _FALSE_VALUES = {None, False, "False", "FALSE", "false", "0", "0.0"}
+    _TRUE_VALUES = {"True", "TRUE", "true", "1", "1.0"}
+    _FALSE_VALUES = {"False", "FALSE", "false", "0", "0.0"}
+    _NONE_VALUES = {"nan"}
 
     @classmethod
     def _simple_new(cls, values: np.ndarray, mask: npt.NDArray[np.bool_]) -> Self:
@@ -329,15 +330,19 @@ def _from_sequence_of_strings(
         copy: bool = False,
         true_values: list[str] | None = None,
         false_values: list[str] | None = None,
+        none_values: list[str] | None = None,
     ) -> BooleanArray:
         true_values_union = cls._TRUE_VALUES.union(true_values or [])
         false_values_union = cls._FALSE_VALUES.union(false_values or [])
+        none_values_union = cls._NONE_VALUES.union(none_values or [])
 
         def map_string(s) -> bool:
             if s in true_values_union:
                 return True
             elif s in false_values_union:
                 return False
+            elif s in none_values_union:
+                return None
             else:
                 raise ValueError(f"{s} cannot be cast to bool")
 

diff --git a/pandas/io/parsers/base_parser.py b/pandas/io/parsers/base_parser.py
@@ -753,18 +753,11 @@ def _cast_types(self, values: ArrayLike, cast_type: DtypeObj, column) -> ArrayLi
                         true_values=self.true_values,
                         false_values=self.false_values,
                     )
-                elif isinstance(cast_type, BooleanDtype) and all(
-                    isinstance(value, bool) for value in values
-                ):
-                    values = [str(val) for val in values]
-                    return array_type._from_sequence_of_strings(  # type: ignore[call-arg]
-                        values,
-                        dtype=cast_type,
-                        true_values=self.true_values,
-                        false_values=self.false_values,
-                    )
                 else:
-                    return array_type._from_sequence_of_strings(values, dtype=cast_type)
+                    values_str = [str(val) for val in values]
+                    return array_type._from_sequence_of_strings(
+                        values_str, dtype=cast_type
+                    )
             except NotImplementedError as err:
                 raise NotImplementedError(
                     f"Extension Array: {array_type} must implement "