Shallow rendering should support context

[graue]

The shallow renderer's render method currently accepts a second (undocumented) argument, context, but values you pass don't actually make it through. If you pass {foo: 'bar'} the component receives the context object {foo: undefined}.

Related: #2393, #3696

[glenjamin]

From what I can tell, this is related to the owner/parent context changes discussed in https://gist.github.com/jimfb/0eb6e61f300a8c1b2ce7

0.13 still uses owner-based contexts, so there's no owner context - but I guess master uses parent-based context so the test passes?

[glenjamin]

Here's a little workaround I ended up doing to ensure both owner-context and parent-context is set when using shallow rendering for testing.

function shallowRender(makeComponent, context) {
  context = context || {};
  var ReactContext = require('react/lib/ReactContext');
  ReactContext.current = context;
  var shallowRenderer = TestUtils.createRenderer();
  shallowRenderer.render(makeComponent(), context);
  ReactContext.current = {};
  return shallowRenderer.getRenderOutput();;
}

// Usage:
var output = shallowRender(() =>
  <MyComponent
    with={props}
    and={stuff}
  />,
  { here: 'is', my: 'context'}
);

Note use of the arrow function to delay creation of the component until owner-context can be set.

[vegetabill]

I'm trying out the shallow renderer and my components are using ReactIntl.

I have to render them like this: shallowRenderer.render(element, { locales: null, messages: null }); so that I won't get an error about there being no locales key in the context during ReactCompositeComponentMixin._maskContext.

Is this a general limitation related to this issue or does that sound like something specific to the ReactIntl library?

[mmw]

How would you use shallowRender with ReactTestUtils#Simulate? I'm trying to test interactions on an element that needs context but also needs renderIntoDocument so findRenderedDOMComponentWithClass can find the dom node to simulate events on.

edit: I now realize that this is a naive question and I should be looking for a way to renderIntoDocument with context for the problem I was trying to solve

[graue]

Looks like this got fixed at some point. I'm not sure when, but there's been a passing test since #3912 was merged. Yay!