test(groupby): add test for float overflow

Author: Alvaro-Kothe

pandas/tests/groupby/test_libgroupby.py

@@ -329,3 +329,40 @@ def test_cython_group_sum_Inf_at_beginning_and_end(values, out):
         actual,
         expected,
     )
+
+
+@pytest.mark.parametrize(
+    "values, expected_values",
+    [
+        (np.finfo(np.float64).max, [[np.inf]]),
+        (np.finfo(np.float64).min, [[-np.inf]]),
+        (
+            np.complex128(np.finfo(np.float64).min, np.finfo(np.float64).max),
+            [[np.complex128(-np.inf, np.inf)]],
+        ),
+        (
+            np.complex128(np.finfo(np.float64).max, np.finfo(np.float64).min),
+            [[np.complex128(np.inf, -np.inf)]],
+        ),
+        (
+            np.complex128(np.finfo(np.float64).max, np.finfo(np.float64).max),
+            [[np.complex128(np.inf, np.inf)]],
+        ),
+        (
+            np.complex128(np.finfo(np.float64).min, np.finfo(np.float64).min),
+            [[np.complex128(-np.inf, -np.inf)]],
+        ),
+    ],
+)
+def test_cython_group_sum_overflow(values, expected_values):
+    # GH-60303
+    data = np.array([[values] for _ in range(3)])
+    labels = np.array([0, 0, 0], dtype=np.intp)
+    counts = np.array([0], dtype="int64")
+
+    expected = np.array(expected_values, dtype=values.dtype)
+    actual = np.zeros_like(expected)
+
+    group_sum(actual, counts, data, labels, None, is_datetimelike=False)
+
+    tm.assert_numpy_array_equal(actual, expected)