Bug: Fix inconsistent behavior in searchsorted (#49620)

Raise error when DataFrame is passed to searchsorted

Author: yqyqyq-W

pandas/core/base.py

@@ -20,6 +20,7 @@
 
 import numpy as np
 
+import pandas as pd
 from pandas._libs import lib
 from pandas._typing import (
     Axis,
@@ -1270,6 +1271,13 @@ def searchsorted(
         sorter: NumpySorter = None,
     ) -> npt.NDArray[np.intp] | np.intp:
 
+        if isinstance(value, pd.DataFrame):
+            msg = (
+                "Value must be array-like or scalar, "
+                f"{type(value).__name__} is not supported"
+            )
+            raise ValueError(msg)
+
         values = self._values
         if not isinstance(values, np.ndarray):
             # Going through EA.searchsorted directly improves performance GH#38083