zertosh / nashorn-react-fail

A nashorn/react bug example

Explanation

When doing serve-side rendering with React (0.12.2) in Nashorn (tested in nashorn 1.8.0_25 on Yosemite), something is going on with components that have a context relationship (as in React context, not this). Depending on the methods defined on the Parent and the Child, it either works or you get one of two errors:

1. TypeError: null is not a function

2. Error: Invariant Violation: Child.getChildContext(): childContextTypes must be defined in order to use getChildContext().

• In the test case, when you get to this point in ReactCompositeComponent.js's _processChildContext, the value of Child.getChildContext is actually the Parent's render function (huh). In our "real" app, Child.getChildContext === null is true, but Child.getChildContext is truthy (wtf).

Test it

You need node and Java 8. npm install and run npm run build && npm start.

In main.js, Parent and Child each have two commented out methods, one is a ReactCompositeComponentInterface method, and the other one is just a randomly named one. Try uncommenting different method combinations and you'll see either error or no error.

Workaround

The "reliable" workaround seems to be to define differently named dummy methods on Parent and Child.

Sigh.