In general, your tests shouldn't produce warnings. This module
causes any warnings to be captured and stored. It automatically
adds an extra test that will run when your script ends to check
that there were no warnings. If there were any warnings, the test
will give a "not ok" and diagnostics of where, when, and what the
warning was, including a stack trace of what was going on when it
occurred.

If some of your tests are supposed to produce warnings then you
should be capturing and checking them with Test::Warn, that way
Test::NoWarnings will not see them and so not complain.

Homepage:
https://metacpan.org/release/Test-NoWarnings
