Add null rendering test

[rstacruz]

Here's a failing test case.

[rstacruz]

okaayyy.. i could've sworn that failed on my machine...

[rstacruz]

okay, I see now: it seems CI will always pass, even if tests fail (!). Have a look at the CI logs and you should see the failure.

[rstacruz]

Relevant: tape-testing/tape-run#27

[anthonyshort]

I'm not entirely sure if it's worth adding this feature when a user could just as easily add a <noscript /> or <div /> instead. What do you think?

[rstacruz]

If undefined is handled, then I'd expect null to be too. This is a very common pattern after all:

return <div>
  { someCondition && <Navigation /> }
  { someCondition && <Content /> }
</div>
/* if someCondition is `null`, then we're screwed */

[anthonyshort]

These tests were added in another branch last week :)