GH1179 Add WriteBuffer[bytes] to to_json method

pandas-stubs/core/frame.pyi

@@ -2291,7 +2291,7 @@ class DataFrame(NDFrame, OpsMixin, _GetItemHack):
     @overload
     def to_json(
         self,
-        path_or_buf: FilePath | WriteBuffer[str],
+        path_or_buf: FilePath | WriteBuffer[str] | WriteBuffer[bytes],
         orient: JsonFrameOrient | None = ...,
         date_format: Literal["epoch", "iso"] | None = ...,
         double_precision: int = ...,

pandas-stubs/core/series.pyi

@@ -594,7 +594,7 @@ class Series(IndexOpsMixin[S1], NDFrame):
     @overload
     def to_json(
         self,
-        path_or_buf: FilePath | WriteBuffer[str],
+        path_or_buf: FilePath | WriteBuffer[str] | WriteBuffer[bytes],
         orient: JsonSeriesOrient | None = ...,
         date_format: Literal["epoch", "iso"] | None = ...,
         double_precision: int = ...,

pyproject.toml

@@ -39,7 +39,7 @@ mypy = "1.15.0"
 pandas = "2.2.3"
 pyarrow = ">=10.0.1"
 pytest = ">=7.1.2"
-pyright = ">=1.1.396,!=1.1.398"
+pyright = "1.1.397"
 poethepoet = ">=0.16.5"
 loguru = ">=0.6.0"
 typing-extensions = ">=4.4.0"

tests/test_io.py

@@ -452,6 +452,22 @@ def test_json():
     check(assert_type(read_json(bin_json), DataFrame), DataFrame)
 
 
+def test_json_dataframe_bytes():
+    """Test DataFrame.to_json with bytesIO buffer."""
+    buffer = io.BytesIO()
+    df = pd.DataFrame()
+    check(assert_type(df.to_json(buffer, compression="gzip"), None), type(None))
+    check(assert_type(df.to_json(buffer), None), type(None))
+
+
+def test_json_series_bytes():
+    """Test Series.to_json with bytesIO buffer."""
+    buffer = io.BytesIO()
+    sr = pd.Series()
+    check(assert_type(sr.to_json(buffer, compression="gzip"), None), type(None))
+    check(assert_type(sr.to_json(buffer), None), type(None))
+
+
 def test_json_series():
     s = DF["a"]
     with ensure_clean() as path: