BUG: Fix numpy boolean subtraction error in Series.diff

pandas/core/algorithms.py

@@ -1933,6 +1933,7 @@ def diff(arr, n, axis=0):
 
     elif is_bool_dtype(dtype):
         dtype = np.object_
+        is_bool = True
 
     elif is_integer_dtype(dtype):
         dtype = np.float64
@@ -1972,6 +1973,8 @@ def diff(arr, n, axis=0):
             result = res - lag
             result[mask] = na
             out_arr[res_indexer] = result
+        elif is_bool:
+            out_arr[res_indexer] = arr[res_indexer] ^ arr[lag_indexer]
         else:
             out_arr[res_indexer] = arr[res_indexer] - arr[lag_indexer]