From 2114a3c437953d7a375d9462a87cbea4188c490c Mon Sep 17 00:00:00 2001
From: Patrick Hoefler <patrick_hoefler@gmx.net>
Date: Tue, 7 Mar 2023 14:56:46 +0100
Subject: [PATCH 1/3] ERR: Raise ValueError when non-default index is given for
 orc format

---
 doc/source/whatsnew/v2.1.0.rst |  2 +-
 pandas/io/orc.py               | 16 ++++++++++++++++
 pandas/tests/io/test_orc.py    | 18 ++++++++++++++++++
 3 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v2.1.0.rst b/doc/source/whatsnew/v2.1.0.rst
index 12d35288d1ee6..35718f1f3b1ed 100644
--- a/doc/source/whatsnew/v2.1.0.rst
+++ b/doc/source/whatsnew/v2.1.0.rst
@@ -174,7 +174,7 @@ MultiIndex
 
 I/O
 ^^^
--
+- :meth:`DataFrame.to_orc` now raising ``ValueError`` when non-default :class:`Index` is given (:issue:`0`)
 -
 
 Period
diff --git a/pandas/io/orc.py b/pandas/io/orc.py
index 1b9be9adc1196..3ce8fc690700c 100644
--- a/pandas/io/orc.py
+++ b/pandas/io/orc.py
@@ -29,6 +29,7 @@
     is_unsigned_integer_dtype,
 )
 
+from pandas import RangeIndex
 from pandas.core.arrays import ArrowExtensionArray
 from pandas.core.frame import DataFrame
 
@@ -209,6 +210,21 @@ def to_orc(
     if engine_kwargs is None:
         engine_kwargs = {}
 
+    # validate index
+    # --------------
+
+    # validate that we have only a default index
+    # raise on anything else as we don't serialize the index
+
+    if not df.index.equals(RangeIndex.from_range(range(len(df)))):
+        raise ValueError(
+            "orc does not support serializing a non-default index for the index; "
+            "you can .reset_index() to make the index into column(s)"
+        )
+
+    if df.index.name is not None:
+        raise ValueError("orc does not serialize index meta-data on a default index")
+
     # If unsupported dtypes are found raise NotImplementedError
     # In Pyarrow 8.0.0 this check will no longer be needed
     if pa_version_under8p0:
diff --git a/pandas/tests/io/test_orc.py b/pandas/tests/io/test_orc.py
index 9db19d4eb8448..e7a3d173976e5 100644
--- a/pandas/tests/io/test_orc.py
+++ b/pandas/tests/io/test_orc.py
@@ -406,3 +406,21 @@ def test_orc_uri_path():
         uri = pathlib.Path(path).as_uri()
         result = read_orc(uri)
     tm.assert_frame_equal(result, expected)
+
+
+@pytest.mark.parametrize(
+    "index",
+    [
+        pd.RangeIndex(start=2, stop=5, step=1),
+        pd.RangeIndex(start=0, stop=3, step=1, name="non-default"),
+        pd.Index([1, 2, 3]),
+    ],
+)
+def test_to_orc_non_default_index(index):
+    df = pd.DataFrame({"a": [1, 2, 3]}, index=index)
+    msg = (
+        "orc does not support serializing a non-default index|"
+        "orc does not serialize index meta-data"
+    )
+    with pytest.raises(ValueError, match=msg):
+        df.to_orc()

From 6e7b7aad65408cd688c7799ab26d0cebab8fcbd7 Mon Sep 17 00:00:00 2001
From: Patrick Hoefler <patrick_hoefler@gmx.net>
Date: Tue, 7 Mar 2023 23:53:23 +0000
Subject: [PATCH 2/3] Use default index

---
 pandas/io/orc.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pandas/io/orc.py b/pandas/io/orc.py
index 3ce8fc690700c..a948011a046dc 100644
--- a/pandas/io/orc.py
+++ b/pandas/io/orc.py
@@ -29,9 +29,9 @@
     is_unsigned_integer_dtype,
 )
 
-from pandas import RangeIndex
 from pandas.core.arrays import ArrowExtensionArray
 from pandas.core.frame import DataFrame
+from pandas.core.indexes.api import default_index
 
 from pandas.io.common import (
     get_handle,
@@ -216,7 +216,7 @@ def to_orc(
     # validate that we have only a default index
     # raise on anything else as we don't serialize the index
 
-    if not df.index.equals(RangeIndex.from_range(range(len(df)))):
+    if not df.index.equals(default_index(len(df))):
         raise ValueError(
             "orc does not support serializing a non-default index for the index; "
             "you can .reset_index() to make the index into column(s)"

From 040a1a2531099703f008055dc6bf6915d89f0e8e Mon Sep 17 00:00:00 2001
From: Patrick Hoefler <61934744+phofl@users.noreply.github.com>
Date: Mon, 13 Mar 2023 23:41:09 +0100
Subject: [PATCH 3/3] Update doc/source/whatsnew/v2.1.0.rst

Co-authored-by: Matthew Roeschke <10647082+mroeschke@users.noreply.github.com>
---
 doc/source/whatsnew/v2.1.0.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v2.1.0.rst b/doc/source/whatsnew/v2.1.0.rst
index 35718f1f3b1ed..a0cf6410d3329 100644
--- a/doc/source/whatsnew/v2.1.0.rst
+++ b/doc/source/whatsnew/v2.1.0.rst
@@ -174,7 +174,7 @@ MultiIndex
 
 I/O
 ^^^
-- :meth:`DataFrame.to_orc` now raising ``ValueError`` when non-default :class:`Index` is given (:issue:`0`)
+- :meth:`DataFrame.to_orc` now raising ``ValueError`` when non-default :class:`Index` is given (:issue:`51828`)
 -
 
 Period