`TEMPLATE_PRODUCT_TEST_CASE` trips up `-Wsign-conversion`

[cjdb]

Describe the bug TEMPLATE_PRODUCT_TEST_CASE's internals do something to trip up -Wsign-conversion, which causes problems for user code.

Expected behavior No warning should be visible from user code.

Reproduction steps

// g++-11 -Werror=sign-conversion
#include <catch.hpp>
#include <vector>

TEMPLATE_PRODUCT_TEST_CASE("hello", "", (std::vector), (int)) {}

Compiler Explorer

Platform information:

• OS: Ubuntu 20.04
• Compiler+version: GCC 11
• Catch version: v2.13.8 locally; trunk on Compiler Explorer

[horenmar]

Okay, I see this is open against v2 branch. AFAIK this commit should fix it but it won't apply cleanly.