BREAKING: bind queries to the container

[adams-brian]

What:

Bug fix: bind queries to the container in render

Why:

The docs state that "the most important feature of render is that the queries from dom-testing-library are automatically returned with their first argument bound to the rendered container".

But if no container was passed to render, the queries it was returning were bound to document.body (code here and here).

How:

This PR ensures the queries are bound to the container, adds a corresponding unit test, and fixes an older unit test that was only passing because the queries were being incorrectly bound to document.body.

Checklist:

• Documentation N/A
• Tests
• Ready to be merged
  
• Added myself to contributors table
  

Additional comments

Bug was found while responding to this StackOverflow issue

[alexkrolick]

1. The current behavior is actually intentional to support querying Portals and other elements that render outside the root node. The docs could be rephrased to reflect this. Querying elements does provide unexpected behavior  #254 (comment)
2. This would be a breaking change. If accepted we would need to add docs to explain how to use within() or unbound dom-testing queries to test modals, etc.

Suggested change:

the most important feature of render is that the queries from dom-testing-library are automatically returned with their first argument bound to the document

[kentcdodds]

Hi @brian-lives-outdoors,

Thanks for the PR, but we will not be making this change. As @alexkrolick mentioned, this is intentional.

If you need this for some reason, then it's likely that you aren't cleaning up the document properly. Make sure to you're using cleanup (or import 'react-testing-library/cleanup-after-each).

Thanks again!

[kentcdodds]

That said, we would accept a PR to the docs to make them more clear here!