BUG: fix to_numeric raises TypeError for Timedelta and Timestamp scalar (#59974)

* BUG: fix to_numeric raises TypeError for Timedelta and Timestamp scalar

* Add whatsnew

Author: yuanx749

doc/source/whatsnew/v3.0.0.rst

@@ -701,6 +701,7 @@ Other
 - Bug in :func:`eval` on :class:`ExtensionArray` on including division ``/`` failed with a ``TypeError``. (:issue:`58748`)
 - Bug in :func:`eval` where the names of the :class:`Series` were not preserved when using ``engine="numexpr"``. (:issue:`10239`)
 - Bug in :func:`eval` with ``engine="numexpr"`` returning unexpected result for float division. (:issue:`59736`)
+- Bug in :func:`to_numeric` raising ``TypeError`` when ``arg`` is a :class:`Timedelta` or :class:`Timestamp` scalar. (:issue:`59944`)
 - Bug in :func:`unique` on :class:`Index` not always returning :class:`Index` (:issue:`57043`)
 - Bug in :meth:`DataFrame.apply` where passing ``engine="numba"`` ignored ``args`` passed to the applied function (:issue:`58712`)
 - Bug in :meth:`DataFrame.eval` and :meth:`DataFrame.query` which caused an exception when using NumPy attributes via ``@`` notation, e.g., ``df.eval("@np.floor(a)")``. (:issue:`58041`)

pandas/core/tools/numeric.py

@@ -11,6 +11,10 @@
     lib,
     missing as libmissing,
 )
+from pandas._libs.tslibs import (
+    Timedelta,
+    Timestamp,
+)
 from pandas.util._validators import check_dtype_backend
 
 from pandas.core.dtypes.cast import maybe_downcast_numeric
@@ -189,6 +193,8 @@ def to_numeric(
             return float(arg)
         if is_number(arg):
             return arg
+        if isinstance(arg, (Timedelta, Timestamp)):
+            return arg._value
         is_scalars = True
         values = np.array([arg], dtype="O")
     elif getattr(arg, "ndim", 1) > 1:

pandas/tests/tools/test_to_numeric.py

@@ -384,6 +384,21 @@ def test_timedelta(transform_assert_equal):
     assert_equal(result, expected)
 
 
+@pytest.mark.parametrize(
+    "scalar",
+    [
+        pd.Timedelta(1, "D"),
+        pd.Timestamp("2017-01-01T12"),
+        pd.Timestamp("2017-01-01T12", tz="US/Pacific"),
+    ],
+)
+def test_timedelta_timestamp_scalar(scalar):
+    # GH#59944
+    result = to_numeric(scalar)
+    expected = to_numeric(Series(scalar))[0]
+    assert result == expected
+
+
 def test_period(request, transform_assert_equal):
     transform, assert_equal = transform_assert_equal