BUG: Series map ignoring na_action for dict or series mapper (pandas-dev#47585)

* BUG: Series map ignoring na_action for dict or series mapper

* Add tests

Author: phofl

doc/source/whatsnew/v1.5.0.rst

@@ -914,6 +914,7 @@ Missing
 ^^^^^^^
 - Bug in :meth:`Series.fillna` and :meth:`DataFrame.fillna` with ``downcast`` keyword not being respected in some cases where there are no NA values present (:issue:`45423`)
 - Bug in :meth:`Series.fillna` and :meth:`DataFrame.fillna` with :class:`IntervalDtype` and incompatible value raising instead of casting to a common (usually object) dtype (:issue:`45796`)
+- Bug in :meth:`Series.map` not respecting ``na_action`` argument if mapper is a ``dict`` or :class:`Series` (:issue:`47527`)
 - Bug in :meth:`DataFrame.interpolate` with object-dtype column not returning a copy with ``inplace=False`` (:issue:`45791`)
 - Bug in :meth:`DataFrame.dropna` allows to set both ``how`` and ``thresh`` incompatible arguments (:issue:`46575`)
 - Bug in :meth:`DataFrame.fillna` ignored ``axis`` when :class:`DataFrame` is single block (:issue:`47713`)

pandas/core/base.py

@@ -843,6 +843,10 @@ def _map_values(self, mapper, na_action=None):
                     f"{na_action} was passed"
                 )
                 raise ValueError(msg)
+
+            if na_action == "ignore":
+                mapper = mapper[mapper.index.notna()]
+
             # Since values were input this means we came from either
             # a dict or a series and mapper should be an index
             if is_categorical_dtype(self.dtype):

pandas/tests/apply/test_series_apply.py

@@ -598,6 +598,34 @@ def test_map_dict_na_key():
     tm.assert_series_equal(result, expected)
 
 
+@pytest.mark.parametrize("arg_func", [dict, Series])
+def test_map_dict_ignore_na(arg_func):
+    # GH#47527
+    mapping = arg_func({1: 10, np.nan: 42})
+    ser = Series([1, np.nan, 2])
+    result = ser.map(mapping, na_action="ignore")
+    expected = Series([10, np.nan, np.nan])
+    tm.assert_series_equal(result, expected)
+
+
+def test_map_defaultdict_ignore_na():
+    # GH#47527
+    mapping = defaultdict(int, {1: 10, np.nan: 42})
+    ser = Series([1, np.nan, 2])
+    result = ser.map(mapping)
+    expected = Series([10, 0, 0])
+    tm.assert_series_equal(result, expected)
+
+
+def test_map_categorical_na_ignore():
+    # GH#47527
+    values = pd.Categorical([1, np.nan, 2], categories=[10, 1])
+    ser = Series(values)
+    result = ser.map({1: 10, np.nan: 42})
+    expected = Series([10, np.nan, np.nan])
+    tm.assert_series_equal(result, expected)
+
+
 def test_map_dict_subclass_with_missing():
     """
     Test Series.map with a dictionary subclass that defines __missing__,