From eb79b08071a441faf1a9e64e7ba9ded29d4d969d Mon Sep 17 00:00:00 2001
From: Lawrence Mitchell <lmitchell@nvidia.com>
Date: Fri, 28 Apr 2023 11:23:26 +0100
Subject: [PATCH 1/3] Allow zero-sized output in compute_column

Closes #13236.
---
 cpp/src/transform/compute_column.cu | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/cpp/src/transform/compute_column.cu b/cpp/src/transform/compute_column.cu
index e11ff437c14..8fa5e75664f 100644
--- a/cpp/src/transform/compute_column.cu
+++ b/cpp/src/transform/compute_column.cu
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020-2022, NVIDIA CORPORATION.
+ * Copyright (c) 2020-2023, NVIDIA CORPORATION.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -97,6 +97,7 @@ std::unique_ptr<column> compute_column(table_view const& table,
 
   auto output_column = cudf::make_fixed_width_column(
     parser.output_type(), table.num_rows(), output_column_mask_state, stream, mr);
+  if (table.num_rows() == 0) { return output_column; }
   auto mutable_output_device =
     cudf::mutable_column_device_view::create(output_column->mutable_view(), stream);
 

From 8e61e3278758d95c83eab0684d81c1df2893ce90 Mon Sep 17 00:00:00 2001
From: Lawrence Mitchell <lmitchell@nvidia.com>
Date: Fri, 28 Apr 2023 11:30:38 +0100
Subject: [PATCH 2/3] Add test of AST addition on empty table

---
 cpp/tests/ast/transform_tests.cpp | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/cpp/tests/ast/transform_tests.cpp b/cpp/tests/ast/transform_tests.cpp
index 745fa44d45e..737224f2624 100644
--- a/cpp/tests/ast/transform_tests.cpp
+++ b/cpp/tests/ast/transform_tests.cpp
@@ -110,6 +110,22 @@ TEST_F(TransformTest, BasicAddition)
   CUDF_TEST_EXPECT_COLUMNS_EQUAL(expected, result->view(), verbosity);
 }
 
+TEST_F(TransformTest, BasicAdditionEmptyTable)
+{
+  auto c_0   = column_wrapper<int32_t>{};
+  auto c_1   = column_wrapper<int32_t>{};
+  auto table = cudf::table_view{{c_0, c_1}};
+
+  auto col_ref_0  = cudf::ast::column_reference(0);
+  auto col_ref_1  = cudf::ast::column_reference(1);
+  auto expression = cudf::ast::operation(cudf::ast::ast_operator::ADD, col_ref_0, col_ref_1);
+
+  auto expected = column_wrapper<int32_t>{};
+  auto result   = cudf::compute_column(table, expression);
+
+  CUDF_TEST_EXPECT_COLUMNS_EQUAL(expected, result->view(), verbosity);
+}
+
 TEST_F(TransformTest, BasicAdditionCast)
 {
   auto c_0   = column_wrapper<int64_t>{3, 20, 1, 50};

From ea01fa174f820460398ca5c14c6dae851d815202 Mon Sep 17 00:00:00 2001
From: Lawrence Mitchell <lmitchell@nvidia.com>
Date: Fri, 28 Apr 2023 11:38:29 +0100
Subject: [PATCH 3/3] Test df.eval on empty dataframes

---
 python/cudf/cudf/tests/test_dataframe.py | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/python/cudf/cudf/tests/test_dataframe.py b/python/cudf/cudf/tests/test_dataframe.py
index e38d42f1c94..918a10ffd75 100644
--- a/python/cudf/cudf/tests/test_dataframe.py
+++ b/python/cudf/cudf/tests/test_dataframe.py
@@ -9757,9 +9757,19 @@ def test_empty_numeric_only(data):
     assert_eq(expected, actual)
 
 
-@pytest.fixture
-def df_eval():
-    N = 10
+@pytest.fixture(params=[0, 10], ids=["empty", "10"])
+def df_eval(request):
+    N = request.param
+    if N == 0:
+        value = np.zeros(0, dtype="int")
+        return cudf.DataFrame(
+            {
+                "a": value,
+                "b": value,
+                "c": value,
+                "d": value,
+            }
+        )
     int_max = 10
     rng = cupy.random.default_rng(0)
     return cudf.DataFrame(