I've replied to a close ticket here #2764 (comment)

but here the issue:
Since 0.64.0.
This snippet fails to compile:

public class ServiceTests
{
    private const int BatchSize = 42;

    [Test]
    [Arguments(BatchSize)]
    public async Task TestMethod(decimal batchingSize)
    {
       // Test code
    }
}

error CS0103: The name 'BatchSizem' does not exist in the current context   # <- note the extra "m"
error CS0103: The name 'BatchSize' does not exist in the current context

The code generation fails to recognize this is a named constant a suffixes it with the decimal literal.