urlencode with variables loaded from csv

Hi folks,

Can someone please explain to me how JMeter handles variables loaded from
CSV, as opposed to handling user-defined variables? I was under the
impression that ${__urlencode(${csv_variable})} would produce the same
output as ${__urlencode(${user_defined_variable})}, but it appears this is
not the case.

A minimal test case is available at
https://issues.apache.org/bugzilla/attachment.cgi?id=31268. In that test
plan, the CSV data are declared before any of the thread groups, and
urlencode is called within each thread group.

In such a case, wouldn't the CSV variables (defined before the thread
groups in the test plan) be loaded before the user-defined variables
(defined within the thread groups)?

Thanks,
Steve