This is a test helper module, so it is designed to be used in cooperation
with other test modules, such as Test::Simple and Test::More.

The module helps you check through a bunch of code for references to
modules you either (a) want to use, or (b) want to avoid. The module reads
and parses the file (using PPI, and, therefore, dependencies of the file
are not checked). the syntactic check has some advantages. Because no
actual code is loaded, it is safe to use as a test.

One of the best reasons for using this, is to handle code where your
production environment may limit use of modules. This test allows you to
avoid modules that you know are going to cause problems, by adding test
cases which fail when people write code that uses them.
Because pragmas are invoked similarly, you can also detect use of "bad"
pragmas.