Add tests for Series.map() hints.

tests/test_series.py

@@ -3230,3 +3230,47 @@ def test_operator_constistency() -> None:
         pd.Series,
         pd.Timedelta,
     )
+
+
+def test_map() -> None:
+    s = pd.Series([1, 2, 3])
+
+    mapping = {1: "a", 2: "b", 3: "c"}
+    check(
+        assert_type(s.map(mapping, na_action="ignore"), "pd.Series[str]"),
+        pd.Series,
+        str,
+    )
+
+    def callable(x: int) -> str:
+        return str(x)
+
+    check(
+        assert_type(s.map(callable, na_action="ignore"), "pd.Series[str]"),
+        pd.Series,
+        str,
+    )
+
+    series = pd.Series(["a", "b", "c"])
+    check(
+        assert_type(s.map(series, na_action="ignore"), "pd.Series[str]"), pd.Series, str
+    )
+
+
+def test_map_na() -> None:
+    s: pd.Series[int] = pd.Series([1, pd.NA, 3])
+
+    mapping = {1: "a", 2: "b", 3: "c"}
+    check(assert_type(s.map(mapping, na_action=None), "pd.Series[str]"), pd.Series, str)
+
+    def callable(x: int | NAType) -> str | NAType:
+        if isinstance(x, int):
+            return str(x)
+        return x
+
+    check(
+        assert_type(s.map(callable, na_action=None), "pd.Series[str]"), pd.Series, str
+    )
+
+    series = pd.Series(["a", "b", "c"])
+    check(assert_type(s.map(series, na_action=None), "pd.Series[str]"), pd.Series, str)