Adam Szmigin created ARROW-8344:
-----------------------------------
Summary: [C#] StringArray.Builder.Clear() corrupts subsequent
array contents
Key: ARROW-8344
URL: https://issues.apache.org/jira/browse/ARROW-8344
Project: Apache Arrow
Issue Type: Bug
Components: C#
Affects Versions: 0.16.0
Environment: Windows 10 x64
Reporter: Adam Szmigin
h1. Summary
Using the {{Clear()}} method on a {{StringArray.Builder}} class causes all
subsequent built arrays to contain strings consisting solely of whitespace.
The below minimal example illustrates:
{code:java}
namespace ArrowStringArrayBuilderBug
{
using Apache.Arrow;
using Apache.Arrow.Memory;
public class Program
{
private static readonly NativeMemoryAllocator Allocator
= new NativeMemoryAllocator();
public static void Main()
{
var builder = new StringArray.Builder();
AppendBuildPrint(builder, "Hello", "World");
builder.Clear();
AppendBuildPrint(builder, "Foo", "Bar");
}
private static void AppendBuildPrint(
StringArray.Builder builder, params string[] strings)
{
foreach (var elem in strings)
builder.Append(elem);
var arr = builder.Build(Allocator);
System.Console.Write("Array contents: [");
for (var i = 0; i < arr.Length; i++)
{
if (i > 0) System.Console.Write(", ");
System.Console.Write($"'{arr.GetString(i)}'");
}
System.Console.WriteLine("]");
}
}
{code}
h2. Expected Output
{noformat}
Array contents: ['Hello', 'World']
Array contents: ['Foo', 'Bar']
{noformat}
h2. Actual Output
{noformat}
Array contents: ['Hello', 'World']
Array contents: [' ', ' '] {noformat}
h1. Workaround
The bug can be trivially worked around by constructing a new
{{StringArray.Builder}} instead of calling {{Clear()}}.
The issue ARROW-7040 mentions other issues with string arrays in C#, but I'm
not sure if this is related or not.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
