Tests: extend pre-compiler unit tests to check macro permutations

Tests: extend pre-compiler unit tests to check macro permutations

We are getting come complaints about precompiler issues building with
#if FOO && FOO || FOO boolean constructs using undefined macros.

The particualr form reported so far dies when building the test, so will
be found earlier than these checks are run. This is to ensure its not a
widespread subtle error in other "working" installations.