Improve groupby test utils to include the original location of failure

[ttnghia]

Currently, many groupby tests call to test_single_agg() and other utility functions in groupby_test_util.* (test_sum_agg() and test_single_scan()) to execute the test. When a failure happens, GTest only issues a trace location to somewhere in test_single_agg() while there is not any information about the actual failed test. That makes debugging a bit tricky.

This PR reimplements thesef test functions, adding one more parameter std::source_location const& location = std::source_location::current() to carry the caller's information. With this, GTest will report an additional line containing the location of the failed test. For example:

Google Test trace:
cudf/cpp/tests/groupby/groupby_test_util.cpp:75:  <--  line of failure

cudf/cpp/tests/groupby/groupby_test_util.cpp:36: Original failure location: cudf/cpp/tests/groupby/sum_tests.cpp:192

[pmattione-nvidia]

Instead of creating macros and modifying hundreds of call sites, you should just be able to add a default argument to the end of each method of std::source_location. The example in that link shows how you can default the argument to std::source_location::current() and it will capture the same information.

[ttnghia]

Instead of creating macros and modifying hundreds of call sites, you should just be able to add a default argument to the end of each method of std::source_location. The example in that link shows how you can default the argument to std::source_location::current() and it will capture the same information.

That is great. I've modified the code using that approach.

[davidwendt]

This looks great.
Can you add a comment which shows how the output would look now on a failure with this implementation?

[ttnghia]

This looks great. Can you add a comment which shows how the output would look now on a failure with this implementation?

Yes, the output should look the same as reported in the PR description: #20718 (comment).

[ttnghia]

/merge