From e04e1f787705fb7b4cb64408bfcbb5ddb52213b3 Mon Sep 17 00:00:00 2001
From: RajatS Mukherjee <raromukherjee@gmail.com>
Date: Thu, 17 Aug 2023 10:43:14 +0000
Subject: [PATCH 1/2] deprecated non keyword arguments

---
 doc/source/whatsnew/v2.2.0.rst       |  2 +-
 pandas/core/generic.py               |  3 +++
 pandas/tests/generic/test_generic.py | 10 ++++++++++
 3 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v2.2.0.rst b/doc/source/whatsnew/v2.2.0.rst
index c35473b852eb9..9295ad6cb9aa6 100644
--- a/doc/source/whatsnew/v2.2.0.rst
+++ b/doc/source/whatsnew/v2.2.0.rst
@@ -92,7 +92,7 @@ Other API changes
 
 Deprecations
 ~~~~~~~~~~~~
--
+- Deprecated allowing non-keyword arguments in :meth:`DataFrame.to_pickle` except ``path``. (:issue:`54229`)
 -
 
 .. ---------------------------------------------------------------------------
diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index 7624c8f7c7930..88fa32ca5b20b 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -3017,6 +3017,9 @@ def to_sql(
         )
 
     @final
+    @deprecate_nonkeyword_arguments(
+        version=None, allowed_args=["self", "path"], name="to_pickle"
+    )
     @doc(
         storage_options=_shared_docs["storage_options"],
         compression_options=_shared_docs["compression_options"] % "path",
diff --git a/pandas/tests/generic/test_generic.py b/pandas/tests/generic/test_generic.py
index 87beab04bc586..7b5b31037d445 100644
--- a/pandas/tests/generic/test_generic.py
+++ b/pandas/tests/generic/test_generic.py
@@ -460,3 +460,13 @@ def test_bool_dep(self) -> None:
         )
         with tm.assert_produces_warning(FutureWarning, match=msg_warn):
             DataFrame({"col": [False]}).bool()
+
+    def test_drop_pos_args_deprecation_for_to_pickle(self):
+        # GH-54229
+        df = DataFrame({"a": [1, 2, 3]})
+        msg = (
+            r"In a future version of pandas all arguments of to_pickle "
+            r"except for the argument 'path' will be keyword-only"
+        )
+        with tm.assert_produces_warning(FutureWarning, match=msg):
+            df.to_pickle("./dummy.pkl", "infer")

From 6790da32eca039ca06a049f5a09d9ea984341f9e Mon Sep 17 00:00:00 2001
From: RajatS Mukherjee <raromukherjee@gmail.com>
Date: Thu, 17 Aug 2023 16:18:28 +0000
Subject: [PATCH 2/2] addressed review comments

---
 pandas/core/generic.py               |  2 +-
 pandas/tests/generic/test_generic.py | 10 ----------
 pandas/tests/io/test_pickle.py       | 12 ++++++++++++
 3 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index 88fa32ca5b20b..8b1540efcef54 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -3018,7 +3018,7 @@ def to_sql(
 
     @final
     @deprecate_nonkeyword_arguments(
-        version=None, allowed_args=["self", "path"], name="to_pickle"
+        version="3.0", allowed_args=["self", "path"], name="to_pickle"
     )
     @doc(
         storage_options=_shared_docs["storage_options"],
diff --git a/pandas/tests/generic/test_generic.py b/pandas/tests/generic/test_generic.py
index 7b5b31037d445..87beab04bc586 100644
--- a/pandas/tests/generic/test_generic.py
+++ b/pandas/tests/generic/test_generic.py
@@ -460,13 +460,3 @@ def test_bool_dep(self) -> None:
         )
         with tm.assert_produces_warning(FutureWarning, match=msg_warn):
             DataFrame({"col": [False]}).bool()
-
-    def test_drop_pos_args_deprecation_for_to_pickle(self):
-        # GH-54229
-        df = DataFrame({"a": [1, 2, 3]})
-        msg = (
-            r"In a future version of pandas all arguments of to_pickle "
-            r"except for the argument 'path' will be keyword-only"
-        )
-        with tm.assert_produces_warning(FutureWarning, match=msg):
-            df.to_pickle("./dummy.pkl", "infer")
diff --git a/pandas/tests/io/test_pickle.py b/pandas/tests/io/test_pickle.py
index 75e4de7074e63..a30b3f64bd75c 100644
--- a/pandas/tests/io/test_pickle.py
+++ b/pandas/tests/io/test_pickle.py
@@ -585,3 +585,15 @@ def test_pickle_frame_v124_unpickle_130(datapath):
 
     expected = pd.DataFrame(index=[], columns=[])
     tm.assert_frame_equal(df, expected)
+
+
+def test_pickle_pos_args_deprecation():
+    # GH-54229
+    df = pd.DataFrame({"a": [1, 2, 3]})
+    msg = (
+        r"Starting with pandas version 3.0 all arguments of to_pickle except for the "
+        r"argument 'path' will be keyword-only."
+    )
+    with tm.assert_produces_warning(FutureWarning, match=msg):
+        buffer = io.BytesIO()
+        df.to_pickle(buffer, "infer")