npgsql: Bug: TimeSpan 24:00:00 is truncated to 00:00:00

PostgreSQL allows time type to store values from 00:00:00 to 24:00:00: https://www.postgresql.org/docs/9.6/datatype-datetime.html

However, if I try to store TimeSpan.FromHours(24) using Npgsql, it will be converted to 00:00:00.

In the following unit test only one case will succeed:

public class NpgsqlTimeSpanTests
{
    public static IEnumerable<object[]> TestCases
    {
        get
        {
            yield return new object[] { TimeSpan.FromHours(24).Add(TimeSpan.FromMilliseconds(-1)) };
            // this will fail
            yield return new object[] { TimeSpan.FromHours(24) };
        }
    }

    [Theory]
    [MemberData(nameof(TestCases), MemberType = typeof(NpgsqlTimeSpanTests))]
    public async Task TimeSpan24Hours_Test(TimeSpan time)
    {
        using (var connection = new NpgsqlConnection("..."))
        {
            await connection.OpenAsync();

            using (var transaction = connection.BeginTransaction())
            {
                using (var command = connection.CreateCommand())
                {
                    command.CommandText = "CREATE TABLE IF NOT EXISTS timespantest (ts time without time zone not null)";
                    command.Transaction = transaction;
                    await command.ExecuteNonQueryAsync();
                }

                using (var command = connection.CreateCommand())
                {
                    command.CommandText = "INSERT INTO timespantest (ts) VALUES (@ts)";
                    command.Transaction = transaction;
                    command.Parameters.AddWithValue("@ts", time);
                    await command.ExecuteNonQueryAsync();
                }

                // make sure the returned value is the same what we saved
                using (var command = connection.CreateCommand())
                {
                    command.CommandText = "SELECT ts FROM timespantest LIMIT 1";
                    command.Transaction = transaction;
                    var value = (TimeSpan) await command.ExecuteScalarAsync();

                    Assert.Equal(value, time);
                }

                await transaction.RollbackAsync();
            }
        }
    }
}