BUG: Don't cache args during rolling/expanding.apply with numba engine

doc/source/whatsnew/v1.4.0.rst

@@ -189,7 +189,7 @@ Plotting
 
 Groupby/resample/rolling
 ^^^^^^^^^^^^^^^^^^^^^^^^
--
+- Bug in :meth:`Series.rolling.apply`, :meth:`DataFrame.rolling.apply`, :meth:`Series.expanding.apply` and :meth:`DataFrame.expanding.apply` with ``engine="numba"`` where ``*args`` were being cached with the user passed function (:issue:`42287`)
 -
 
 Reshaping

pandas/core/window/numba_.py

@@ -19,7 +19,6 @@
 
 
 def generate_numba_apply_func(
-    args: tuple,
     kwargs: dict[str, Any],
     func: Callable[..., Scalar],
     engine_kwargs: dict[str, bool] | None,
@@ -36,8 +35,6 @@ def generate_numba_apply_func(
 
     Parameters
     ----------
-    args : tuple
-        *args to be passed into the function
     kwargs : dict
         **kwargs to be passed into the function
     func : function
@@ -62,7 +59,11 @@ def generate_numba_apply_func(
 
     @numba.jit(nopython=nopython, nogil=nogil, parallel=parallel)
     def roll_apply(
-        values: np.ndarray, begin: np.ndarray, end: np.ndarray, minimum_periods: int
+        values: np.ndarray,
+        begin: np.ndarray,
+        end: np.ndarray,
+        minimum_periods: int,
+        *args: Any,
     ) -> np.ndarray:
         result = np.empty(len(begin))
         for i in numba.prange(len(result)):
@@ -169,7 +170,6 @@ def ewma(
 
 
 def generate_numba_table_func(
-    args: tuple,
     kwargs: dict[str, Any],
     func: Callable[..., np.ndarray],
     engine_kwargs: dict[str, bool] | None,
@@ -187,8 +187,6 @@ def generate_numba_table_func(
 
     Parameters
     ----------
-    args : tuple
-        *args to be passed into the function
     kwargs : dict
         **kwargs to be passed into the function
     func : function
@@ -213,7 +211,11 @@ def generate_numba_table_func(
 
     @numba.jit(nopython=nopython, nogil=nogil, parallel=parallel)
     def roll_table(
-        values: np.ndarray, begin: np.ndarray, end: np.ndarray, minimum_periods: int
+        values: np.ndarray,
+        begin: np.ndarray,
+        end: np.ndarray,
+        minimum_periods: int,
+        *args: Any,
     ):
         result = np.empty(values.shape)
         min_periods_mask = np.empty(values.shape)

pandas/core/window/rolling.py

@@ -482,6 +482,7 @@ def _apply(
         func: Callable[..., Any],
         name: str | None = None,
         numba_cache_key: tuple[Callable, str] | None = None,
+        numba_args: tuple[Any, ...] = (),
         **kwargs,
     ):
         """
@@ -495,6 +496,8 @@ def _apply(
         name : str,
         numba_cache_key : tuple
             caching key to be used to store a compiled numba func
+        numba_args : tuple
+            args to be passed when func is a numba func
         **kwargs
             additional arguments for rolling function and window function
 
@@ -522,7 +525,7 @@ def calc(x):
                     center=self.center,
                     closed=self.closed,
                 )
-                return func(x, start, end, min_periods)
+                return func(x, start, end, min_periods, *numba_args)
 
             with np.errstate(all="ignore"):
                 if values.ndim > 1 and self.method == "single":
@@ -583,12 +586,14 @@ def _apply(
         func: Callable[..., Any],
         name: str | None = None,
         numba_cache_key: tuple[Callable, str] | None = None,
+        numba_args: tuple[Any, ...] = (),
         **kwargs,
     ) -> FrameOrSeries:
         result = super()._apply(
             func,
             name,
             numba_cache_key,
+            numba_args,
             **kwargs,
         )
         # Reconstruct the resulting MultiIndex
@@ -969,6 +974,7 @@ def _apply(
         func: Callable[[np.ndarray, int, int], np.ndarray],
         name: str | None = None,
         numba_cache_key: tuple[Callable, str] | None = None,
+        numba_args: tuple[Any, ...] = (),
         **kwargs,
     ):
         """
@@ -982,6 +988,8 @@ def _apply(
         name : str,
         use_numba_cache : tuple
             unused
+        numba_args : tuple
+            unused
         **kwargs
             additional arguments for scipy windows if necessary
 
@@ -1159,18 +1167,20 @@ def apply(
             raise ValueError("raw parameter must be `True` or `False`")
 
         numba_cache_key = None
+        numba_args: tuple[Any, ...] = ()
         if maybe_use_numba(engine):
             if raw is False:
                 raise ValueError("raw must be `True` when using the numba engine")
             caller_name = type(self).__name__
+            numba_args = args
             if self.method == "single":
                 apply_func = generate_numba_apply_func(
-                    args, kwargs, func, engine_kwargs, caller_name
+                    kwargs, func, engine_kwargs, caller_name
                 )
                 numba_cache_key = (func, f"{caller_name}_apply_single")
             else:
                 apply_func = generate_numba_table_func(
-                    args, kwargs, func, engine_kwargs, f"{caller_name}_apply"
+                    kwargs, func, engine_kwargs, f"{caller_name}_apply"
                 )
                 numba_cache_key = (func, f"{caller_name}_apply_table")
         elif engine in ("cython", None):
@@ -1183,6 +1193,7 @@ def apply(
         return self._apply(
             apply_func,
             numba_cache_key=numba_cache_key,
+            numba_args=numba_args,
         )
 
     def _generate_cython_apply_func(

pandas/tests/window/conftest.py

@@ -84,6 +84,12 @@ def min_periods(request):
     return request.param
 
 
+@pytest.fixture(params=["single", "table"])
+def method(request):
+    """method keyword in rolling/expanding/ewm constructor"""
+    return request.param
+
+
 @pytest.fixture(params=[True, False])
 def parallel(request):
     """parallel keyword argument for numba.jit"""

pandas/tests/window/test_numba.py

@@ -121,6 +121,34 @@ def func_2(x):
         expected = roll.apply(func_1, engine="cython", raw=True)
         tm.assert_series_equal(result, expected)
 
+    @pytest.mark.parametrize(
+        "window,window_kwargs",
+        [
+            ["rolling", {"window": 3, "min_periods": 0}],
+            ["expanding", {}],
+        ],
+    )
+    def test_dont_cache_args(
+        self, window, window_kwargs, nogil, parallel, nopython, method
+    ):
+        # GH 42287
+
+        def add(values, x):
+            return np.sum(values) + x
+
+        df = DataFrame({"value": [0, 0, 0]})
+        result = getattr(df, window)(**window_kwargs).apply(
+            add, raw=True, engine="numba", args=(1,)
+        )
+        expected = DataFrame({"value": [1.0, 1.0, 1.0]})
+        tm.assert_frame_equal(result, expected)
+
+        result = getattr(df, window)(**window_kwargs).apply(
+            add, raw=True, engine="numba", args=(2,)
+        )
+        expected = DataFrame({"value": [2.0, 2.0, 2.0]})
+        tm.assert_frame_equal(result, expected)
+
 
 @td.skip_if_no("numba", "0.46.0")
 class TestEWMMean: