update tests correspondingly

pandas/core/generic.py

@@ -11819,24 +11819,33 @@ def pct_change(
         APPL -0.252395 -0.011860   NaN
         """
         # GH#53491
-        msg = (
-            "The 'fill_method' keyword being not None and the 'limit' keyword in "
-            f"{type(self).__name__}.pct_change are deprecated and will be removed "
-            "in a future version. Either fill in any non-leading NA values prior "
-            "to calling pct_change or specify 'fill_method=None' to not fill NA "
-            "values."
-        )
         if fill_method not in (lib.no_default, None) or limit is not lib.no_default:
-            warnings.warn(msg, FutureWarning, stacklevel=find_stack_level())
+            warnings.warn(
+                "The 'fill_method' keyword being not None and the 'limit' keyword in "
+                f"{type(self).__name__}.pct_change are deprecated and will be removed "
+                "in a future version. Either fill in any non-leading NA values prior "
+                "to calling pct_change or specify 'fill_method=None' to not fill NA "
+                "values.",
+                FutureWarning,
+                stacklevel=find_stack_level(),
+            )
         if fill_method is lib.no_default:
             if limit is lib.no_default:
                 cols = self.items() if self.ndim == 2 else [(None, self)]
                 for _, col in cols:
                     mask = col.isna().values
                     mask = mask[np.argmax(~mask) :]
                     if mask.any():
-                        warnings.warn(msg, FutureWarning, stacklevel=find_stack_level())
-                    break
+                        warnings.warn(
+                            "The default fill_method='pad' in "
+                            f"{type(self).__name__}.pct_change is deprecated and will "
+                            "be removed in a future version. Either fill in any "
+                            "non-leading NA values prior to calling pct_change or "
+                            "specify 'fill_method=None' to not fill NA values.",
+                            FutureWarning,
+                            stacklevel=find_stack_level(),
+                        )
+                        break
             fill_method = "pad"
         if limit is lib.no_default:
             limit = None

pandas/core/groupby/groupby.py

@@ -5338,20 +5338,29 @@ def pct_change(
         goldfish    0.2  0.125
         """
         # GH#53491
-        msg = (
-            "The 'fill_method' keyword being not None and the 'limit' keyword in "
-            f"{type(self).__name__}.pct_change are deprecated and will be removed "
-            "in a future version. Either fill in any non-leading NA values prior "
-            "to calling pct_change or specify 'fill_method=None' to not fill NA "
-            "values."
-        )
         if fill_method not in (lib.no_default, None) or limit is not lib.no_default:
-            warnings.warn(msg, FutureWarning, stacklevel=find_stack_level())
+            warnings.warn(
+                "The 'fill_method' keyword being not None and the 'limit' keyword in "
+                f"{type(self).__name__}.pct_change are deprecated and will be removed "
+                "in a future version. Either fill in any non-leading NA values prior "
+                "to calling pct_change or specify 'fill_method=None' to not fill NA "
+                "values.",
+                FutureWarning,
+                stacklevel=find_stack_level(),
+            )
         if fill_method is lib.no_default:
             if limit is lib.no_default and any(
                 grp.isna().values.any() for _, grp in self
             ):
-                warnings.warn(msg, FutureWarning, stacklevel=find_stack_level())
+                warnings.warn(
+                    "The default fill_method='ffill' in "
+                    f"{type(self).__name__}.pct_change is deprecated and will "
+                    "be removed in a future version. Either fill in any "
+                    "non-leading NA values prior to calling pct_change or "
+                    "specify 'fill_method=None' to not fill NA values.",
+                    FutureWarning,
+                    stacklevel=find_stack_level(),
+                )
             fill_method = "ffill"
         if limit is lib.no_default:
             limit = None

pandas/tests/frame/methods/test_pct_change.py

@@ -29,7 +29,7 @@ def test_pct_change_with_nas(
         obj = frame_or_series(vals)
 
         msg = (
-            "The 'fill_method' and 'limit' keywords in "
+            "The 'fill_method' keyword being not None and the 'limit' keyword in "
             f"{type(obj).__name__}.pct_change are deprecated"
         )
         with tm.assert_produces_warning(FutureWarning, match=msg):
@@ -46,7 +46,7 @@ def test_pct_change_numeric(self):
         pnl.iat[2, 3] = 60
 
         msg = (
-            "The 'fill_method' and 'limit' keywords in "
+            "The 'fill_method' keyword being not None and the 'limit' keyword in "
             "DataFrame.pct_change are deprecated"
         )
 
@@ -59,12 +59,11 @@ def test_pct_change_numeric(self):
 
     def test_pct_change(self, datetime_frame):
         msg = (
-            "The 'fill_method' and 'limit' keywords in "
+            "The 'fill_method' keyword being not None and the 'limit' keyword in "
             "DataFrame.pct_change are deprecated"
         )
 
-        with tm.assert_produces_warning(FutureWarning, match=msg):
-            rs = datetime_frame.pct_change(fill_method=None)
+        rs = datetime_frame.pct_change(fill_method=None)
         tm.assert_frame_equal(rs, datetime_frame / datetime_frame.shift(1) - 1)
 
         rs = datetime_frame.pct_change(2)
@@ -110,7 +109,7 @@ def test_pct_change_periods_freq(
         self, datetime_frame, freq, periods, fill_method, limit
     ):
         msg = (
-            "The 'fill_method' and 'limit' keywords in "
+            "The 'fill_method' keyword being not None and the 'limit' keyword in "
             "DataFrame.pct_change are deprecated"
         )
 
@@ -144,12 +143,15 @@ def test_pct_change_with_duplicated_indices(fill_method):
         {0: [np.nan, 1, 2, 3, 9, 18], 1: [0, 1, np.nan, 3, 9, 18]}, index=["a", "b"] * 3
     )
 
-    msg = (
-        "The 'fill_method' and 'limit' keywords in "
-        "DataFrame.pct_change are deprecated"
-    )
-    with tm.assert_produces_warning(FutureWarning, match=msg):
-        result = data.pct_change(fill_method=fill_method)
+    if fill_method is not None:
+        msg = (
+            "The 'fill_method' keyword being not None and the 'limit' keyword in "
+            "DataFrame.pct_change are deprecated"
+        )
+        with tm.assert_produces_warning(FutureWarning, match=msg):
+            result = data.pct_change(fill_method=fill_method)
+    else:
+        result = data.pct_change(fill_method=None)
 
     if fill_method is None:
         second_column = [np.nan, np.inf, np.nan, np.nan, 2.0, 1.0]

pandas/tests/groupby/transform/test_transform.py

@@ -1071,7 +1071,7 @@ def test_pct_change(frame_or_series, freq, periods, fill_method, limit):
         expected = expected.to_frame("vals")
 
     msg = (
-        "The 'fill_method' and 'limit' keywords in "
+        "The 'fill_method' keyword being not None and the 'limit' keyword in "
         f"{type(gb).__name__}.pct_change are deprecated"
     )
     with tm.assert_produces_warning(FutureWarning, match=msg):

pandas/tests/series/methods/test_pct_change.py

@@ -11,12 +11,11 @@
 class TestSeriesPctChange:
     def test_pct_change(self, datetime_series):
         msg = (
-            "The 'fill_method' and 'limit' keywords in "
+            "The 'fill_method' keyword being not None and the 'limit' keyword in "
             "Series.pct_change are deprecated"
         )
 
-        with tm.assert_produces_warning(FutureWarning, match=msg):
-            rs = datetime_series.pct_change(fill_method=None)
+        rs = datetime_series.pct_change(fill_method=None)
         tm.assert_series_equal(rs, datetime_series / datetime_series.shift(1) - 1)
 
         rs = datetime_series.pct_change(2)
@@ -69,7 +68,7 @@ def test_pct_change_periods_freq(
         self, freq, periods, fill_method, limit, datetime_series
     ):
         msg = (
-            "The 'fill_method' and 'limit' keywords in "
+            "The 'fill_method' keyword being not None and the 'limit' keyword in "
             "Series.pct_change are deprecated"
         )
 
@@ -101,9 +100,15 @@ def test_pct_change_with_duplicated_indices(fill_method):
     # GH30463
     s = Series([np.nan, 1, 2, 3, 9, 18], index=["a", "b"] * 3)
 
-    msg = "The 'fill_method' and 'limit' keywords in Series.pct_change are deprecated"
-    with tm.assert_produces_warning(FutureWarning, match=msg):
-        result = s.pct_change(fill_method=fill_method)
+    if fill_method is not None:
+        msg = (
+            "The 'fill_method' keyword being not None and the 'limit' keyword in "
+            "Series.pct_change are deprecated"
+        )
+        with tm.assert_produces_warning(FutureWarning, match=msg):
+            result = s.pct_change(fill_method=fill_method)
+    else:
+        result = s.pct_change()
 
     expected = Series([np.nan, np.nan, 1.0, 0.5, 2.0, 1.0], index=["a", "b"] * 3)
     tm.assert_series_equal(result, expected)