TypeError: Cannot read property '_currentElement' of null

From maintainers: if you have this problem, please see the explanation in https://github.com/facebook/react/issues/6895#issuecomment-281405036.

Test case: jsFiddle

The error is in this function, internalInstance is null.

  /**
   * Releases any resources allocated by `mountComponent`.
   *
   * @final
   * @internal
   */

  unmountComponent: function(internalInstance) {
    ReactRef.detachRefs(internalInstance, internalInstance._currentElement);
    internalInstance.unmountComponent();
  }

I managed to “fix” the bug by simply checking if internal state is not null but that requires modifying react. Other mentions of this bug are listed below.

• http://stackoverflow.com/questions/29786154/upgrading-react-to-0-13-2-causes-uncaught-typeerror-cannot-read-property-cu
• https://github.com/JedWatson/react-select/issues/128
• https://github.com/milankinen/livereactload/issues/8
• https://gist.github.com/jamesknelson/1481521444e1529d59aa

[blairanderson]

@rossPatton in chrome you can activate pause on exception and track down which component path is breaking.

Almost always from rendering code throwing an error and preventing the render from completing.

[tcurdt]

Tracking down these errors is so killing productivity. I don’t even know which component is causing this. @blairanderson How do I get a proper error message? What do you mean by “force render at the top”? Is there anything I could wrap in a try/catch to get to the cause of the error?