From 1b38ede860de6c12224c850409704f4a2fd92127 Mon Sep 17 00:00:00 2001
From: RajatS Mukherjee <raromukherjee@gmail.com>
Date: Fri, 18 Aug 2023 05:59:45 +0000
Subject: [PATCH] deprecated nonkeyword arguments

---
 doc/source/whatsnew/v2.2.0.rst      |  1 +
 pandas/core/generic.py              |  3 +++
 pandas/tests/io/json/test_pandas.py | 17 ++++++++++++++++-
 3 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v2.2.0.rst b/doc/source/whatsnew/v2.2.0.rst
index 4ad450c965464..2a51f2fa1cc50 100644
--- a/doc/source/whatsnew/v2.2.0.rst
+++ b/doc/source/whatsnew/v2.2.0.rst
@@ -93,6 +93,7 @@ Other API changes
 Deprecations
 ~~~~~~~~~~~~
 - Deprecated allowing non-keyword arguments in :meth:`DataFrame.to_hdf` except ``path_or_buf``. (:issue:`54229`)
+- Deprecated allowing non-keyword arguments in :meth:`DataFrame.to_json` except ``path_or_buf``. (:issue:`54229`)
 - Deprecated allowing non-keyword arguments in :meth:`DataFrame.to_latex` except ``buf``. (:issue:`54229`)
 - Deprecated allowing non-keyword arguments in :meth:`DataFrame.to_pickle` except ``path``. (:issue:`54229`)
 - Deprecated allowing non-keyword arguments in :meth:`DataFrame.to_string` except ``buf``. (:issue:`54229`)
diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index c28ae86985896..7da41b890598d 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -2352,6 +2352,9 @@ def to_excel(
         )
 
     @final
+    @deprecate_nonkeyword_arguments(
+        version="3.0", allowed_args=["self", "path_or_buf"], name="to_json"
+    )
     @doc(
         storage_options=_shared_docs["storage_options"],
         compression_options=_shared_docs["compression_options"] % "path_or_buf",
diff --git a/pandas/tests/io/json/test_pandas.py b/pandas/tests/io/json/test_pandas.py
index ff9b4acd96499..4ee9e1e2d1598 100644
--- a/pandas/tests/io/json/test_pandas.py
+++ b/pandas/tests/io/json/test_pandas.py
@@ -1,7 +1,10 @@
 import datetime
 from datetime import timedelta
 from decimal import Decimal
-from io import StringIO
+from io import (
+    BytesIO,
+    StringIO,
+)
 import json
 import os
 import sys
@@ -2106,3 +2109,15 @@ def test_json_roundtrip_string_inference(orient):
         columns=pd.Index(["col 1", "col 2"], dtype=pd.ArrowDtype(pa.string())),
     )
     tm.assert_frame_equal(result, expected)
+
+
+def test_json_pos_args_deprecation():
+    # GH-54229
+    df = DataFrame({"a": [1, 2, 3]})
+    msg = (
+        r"Starting with pandas version 3.0 all arguments of to_json except for the "
+        r"argument 'path_or_buf' will be keyword-only."
+    )
+    with tm.assert_produces_warning(FutureWarning, match=msg):
+        buf = BytesIO()
+        df.to_json(buf, "split")