Support all possible time units for Series.astype literals (#562)

* Support all possible time units for Series.astype literals

* Update test to check all timedelta/timestamp dtype args in a loop

* List out all of the individual string literals in astype test

Author: gandhis1

pandas-stubs/_typing.pyi

@@ -146,8 +146,39 @@ ComplexDtypeArg: TypeAlias = (
     | type[np.complex128]
     | Literal["complex64", "complex128"]
 )
-TimedeltaDtypeArg: TypeAlias = Literal["timedelta64[ns]"]
-TimestampDtypeArg: TypeAlias = Literal["datetime64[ns]"]
+# Refer to https://numpy.org/doc/stable/reference/arrays.datetime.html#datetime-units
+TimedeltaDtypeArg: TypeAlias = Literal[
+    "timedelta64[Y]",
+    "timedelta64[M]",
+    "timedelta64[W]",
+    "timedelta64[D]",
+    "timedelta64[h]",
+    "timedelta64[m]",
+    "timedelta64[s]",
+    "timedelta64[ms]",
+    "timedelta64[us]",
+    "timedelta64[μs]",
+    "timedelta64[ns]",
+    "timedelta64[ps]",
+    "timedelta64[fs]",
+    "timedelta64[as]",
+]
+TimestampDtypeArg: TypeAlias = Literal[
+    "datetime64[Y]",
+    "datetime64[M]",
+    "datetime64[W]",
+    "datetime64[D]",
+    "datetime64[h]",
+    "datetime64[m]",
+    "datetime64[s]",
+    "datetime64[ms]",
+    "datetime64[us]",
+    "datetime64[μs]",
+    "datetime64[ns]",
+    "datetime64[ps]",
+    "datetime64[fs]",
+    "datetime64[as]",
+]
 CategoryDtypeArg: TypeAlias = CategoricalDtype | Literal["category"]
 
 AstypeArg: TypeAlias = (

tests/test_series.py

@@ -1571,17 +1571,147 @@ def test_updated_astype() -> None:
         np.complex128,
     )
 
+    check(
+        assert_type(s.astype("timedelta64[Y]"), TimedeltaSeries),
+        pd.Series,
+        Timedelta,
+    )
+    check(
+        assert_type(s.astype("timedelta64[M]"), TimedeltaSeries),
+        pd.Series,
+        Timedelta,
+    )
+    check(
+        assert_type(s.astype("timedelta64[W]"), TimedeltaSeries),
+        pd.Series,
+        Timedelta,
+    )
+    check(
+        assert_type(s.astype("timedelta64[D]"), TimedeltaSeries),
+        pd.Series,
+        Timedelta,
+    )
+    check(
+        assert_type(s.astype("timedelta64[h]"), TimedeltaSeries),
+        pd.Series,
+        Timedelta,
+    )
+    check(
+        assert_type(s.astype("timedelta64[m]"), TimedeltaSeries),
+        pd.Series,
+        Timedelta,
+    )
+    check(
+        assert_type(s.astype("timedelta64[s]"), TimedeltaSeries),
+        pd.Series,
+        Timedelta,
+    )
+    check(
+        assert_type(s.astype("timedelta64[ms]"), TimedeltaSeries),
+        pd.Series,
+        Timedelta,
+    )
+    check(
+        assert_type(s.astype("timedelta64[us]"), TimedeltaSeries),
+        pd.Series,
+        Timedelta,
+    )
+    check(
+        assert_type(s.astype("timedelta64[μs]"), TimedeltaSeries),
+        pd.Series,
+        Timedelta,
+    )
     check(
         assert_type(s.astype("timedelta64[ns]"), TimedeltaSeries),
         pd.Series,
         Timedelta,
     )
+    check(
+        assert_type(s.astype("timedelta64[ps]"), TimedeltaSeries),
+        pd.Series,
+        Timedelta,
+    )
+    check(
+        assert_type(s.astype("timedelta64[fs]"), TimedeltaSeries),
+        pd.Series,
+        Timedelta,
+    )
+    check(
+        assert_type(s.astype("timedelta64[as]"), TimedeltaSeries),
+        pd.Series,
+        Timedelta,
+    )
 
+    check(
+        assert_type(s.astype("datetime64[Y]"), TimestampSeries),
+        pd.Series,
+        Timestamp,
+    )
+    check(
+        assert_type(s.astype("datetime64[M]"), TimestampSeries),
+        pd.Series,
+        Timestamp,
+    )
+    check(
+        assert_type(s.astype("datetime64[W]"), TimestampSeries),
+        pd.Series,
+        Timestamp,
+    )
+    check(
+        assert_type(s.astype("datetime64[D]"), TimestampSeries),
+        pd.Series,
+        Timestamp,
+    )
+    check(
+        assert_type(s.astype("datetime64[h]"), TimestampSeries),
+        pd.Series,
+        Timestamp,
+    )
+    check(
+        assert_type(s.astype("datetime64[m]"), TimestampSeries),
+        pd.Series,
+        Timestamp,
+    )
+    check(
+        assert_type(s.astype("datetime64[s]"), TimestampSeries),
+        pd.Series,
+        Timestamp,
+    )
+    check(
+        assert_type(s.astype("datetime64[ms]"), TimestampSeries),
+        pd.Series,
+        Timestamp,
+    )
+    check(
+        assert_type(s.astype("datetime64[us]"), TimestampSeries),
+        pd.Series,
+        Timestamp,
+    )
+    check(
+        assert_type(s.astype("datetime64[μs]"), TimestampSeries),
+        pd.Series,
+        Timestamp,
+    )
     check(
         assert_type(s.astype("datetime64[ns]"), TimestampSeries),
         pd.Series,
         Timestamp,
     )
+    check(
+        assert_type(s.astype("datetime64[ps]"), TimestampSeries),
+        pd.Series,
+        Timestamp,
+    )
+    check(
+        assert_type(s.astype("datetime64[fs]"), TimestampSeries),
+        pd.Series,
+        Timestamp,
+    )
+    check(
+        assert_type(s.astype("datetime64[as]"), TimestampSeries),
+        pd.Series,
+        Timestamp,
+    )
 
     orseries = pd.Series([Decimal(x) for x in [1, 2, 3]])
     newtype = DecimalDtype()