Test with no expectation becomes a "skip" (problem for test_examples)

[colearendt]

When testthat runs a test_that with no expectations in it, the result is "Skipped." I think this behavior would preferably be "Passed", since the code was executed without error or skip().

In particular, this is certainly not correct behavior for test_examples(), which should not be expected to have an expectation. As a result, if we can change the behavior for test_example or test_examples() at least, that would be helpful!

Also, if we are not changing the default, is it possible that we could make the "Skip" note more informative? Something like Skipped: No expectation found. I found it quite confusing trying to debug why my tests were getting skipped, when they were in fact being executed but did not have an expectation.

Thanks!

[hadley]

Two features:

• skip_empty() should return a more informative message
• test_example() should call test_code(..., skip_on_empty = FALSE)

[hadley]

First problem was #868