From 729608c17f1530bec48974bdeb20fa6ad90c3c71 Mon Sep 17 00:00:00 2001
From: Thomas Li <thomasli1234567890@gmail.com>
Date: Thu, 27 Jun 2024 00:43:11 +0000
Subject: [PATCH] Fix pylibcudf num_rows for 0 columns case and add interop to
 docs

---
 .../user_guide/api_docs/pylibcudf/index.rst   |  1 +
 .../user_guide/api_docs/pylibcudf/interop.rst |  6 +++++
 python/cudf/cudf/_lib/pylibcudf/table.pyx     |  2 ++
 .../cudf/cudf/pylibcudf_tests/test_table.py   | 22 +++++++++++++++++++
 4 files changed, 31 insertions(+)
 create mode 100644 docs/cudf/source/user_guide/api_docs/pylibcudf/interop.rst
 create mode 100644 python/cudf/cudf/pylibcudf_tests/test_table.py

diff --git a/docs/cudf/source/user_guide/api_docs/pylibcudf/index.rst b/docs/cudf/source/user_guide/api_docs/pylibcudf/index.rst
index f98298ff052..e9dad705cbf 100644
--- a/docs/cudf/source/user_guide/api_docs/pylibcudf/index.rst
+++ b/docs/cudf/source/user_guide/api_docs/pylibcudf/index.rst
@@ -19,6 +19,7 @@ This page provides API documentation for pylibcudf.
     gpumemoryview
     groupby
     io/index.rst
+    interop
     join
     lists
     merge
diff --git a/docs/cudf/source/user_guide/api_docs/pylibcudf/interop.rst b/docs/cudf/source/user_guide/api_docs/pylibcudf/interop.rst
new file mode 100644
index 00000000000..881ab8d7be4
--- /dev/null
+++ b/docs/cudf/source/user_guide/api_docs/pylibcudf/interop.rst
@@ -0,0 +1,6 @@
+=======
+interop
+=======
+
+.. automodule:: cudf._lib.pylibcudf.interop
+   :members:
diff --git a/python/cudf/cudf/_lib/pylibcudf/table.pyx b/python/cudf/cudf/_lib/pylibcudf/table.pyx
index d93ac78721b..d91fa0474b0 100644
--- a/python/cudf/cudf/_lib/pylibcudf/table.pyx
+++ b/python/cudf/cudf/_lib/pylibcudf/table.pyx
@@ -83,6 +83,8 @@ cdef class Table:
 
     cpdef int num_rows(self):
         """The number of rows in this table."""
+        if self.num_columns() == 0:
+            return 0
         return self._columns[0].size()
 
     cpdef list columns(self):
diff --git a/python/cudf/cudf/pylibcudf_tests/test_table.py b/python/cudf/cudf/pylibcudf_tests/test_table.py
new file mode 100644
index 00000000000..cf1d51f6491
--- /dev/null
+++ b/python/cudf/cudf/pylibcudf_tests/test_table.py
@@ -0,0 +1,22 @@
+# Copyright (c) 2024, NVIDIA CORPORATION.
+
+import pyarrow as pa
+import pytest
+
+import cudf._lib.pylibcudf as plc
+
+
+@pytest.mark.parametrize(
+    "arrow_tbl",
+    [
+        pa.table([]),
+        pa.table({"a": [1, 2, 3], "b": [4, 5, 6], "c": [7, 8, 9]}),
+        pa.table({"a": [1, 2, 3]}),
+        pa.table({"a": [1], "b": [2], "c": [3]}),
+    ],
+)
+def test_table_shape(arrow_tbl):
+    plc_tbl = plc.interop.from_arrow(arrow_tbl)
+
+    plc_tbl_shape = (plc_tbl.num_rows(), plc_tbl.num_columns())
+    assert plc_tbl_shape == arrow_tbl.shape