This enumeration is used to indicate the broad category that a [TestCase] falls into.
A "happy path" test may also be known as "green path", "green grass" or similar terms. This kind of test simply proves that the candidate code, under ideal non-stress conditions, does what it is supposed to. It is typically used for build acceptance testing ("smoke testing") to prove basic functionality.
This indicates similar importance to a "happy path" test. A critical test case indicates that the test is against functionality that may render other testing inconclusive if it doesn't work.
This indicates a test of low importance. Exhausting every possible input for all the fields of a class will likely produce a great many ancillary tests. Be careful about creating too many tests that are truly ancillary as managers may not see more important failures amongst all the "clutter" and programmers may not be in a hurry to fix the resulting bugs. In other words, your reports are better off showing specific critical or happy path failures, rather than showing that "1/3 of the thousands of tests that don't matter still fail."
The dafult priority. Indicates that a test is against functionality that matters, even though it may not be so critical as to render other tests inconclusive if it fails.