{"action":"created","issue":{"url":"https://api.github.com/repos/facebook/react/issues/3585","labels_url":"https://api.github.com/repos/facebook/react/issues/3585/labels{/name}","comments_url":"https://api.github.com/repos/facebook/react/issues/3585/comments","events_url":"https://api.github.com/repos/facebook/react/issues/3585/events","html_url":"https://github.com/facebook/react/issues/3585","id":66298695,"number":3585,"title":"Uncaught TypeError: Cannot read property 'context' of 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TypeError: Cannot read property 'context' of nullreact.js:6738 ReactCompositeComponentMixin.updateComponentreact.js:13371 ReactPerf.measure.wrapperreact.js:6647 ReactCompositeComponentMixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:4779 ReactChildReconciler.updateChildrenreact.js:12900 ReactMultiChild.Mixin._updateChildrenreact.js:12874 ReactMultiChild.Mixin.updateChildrenreact.js:7862 ReactDOMComponent.Mixin._updateDOMChildrenreact.js:7713 ReactDOMComponent.Mixin.updateComponentreact.js:7697 ReactDOMComponent.Mixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:6884 ReactCompositeComponentMixin._updateRenderedComponentreact.js:6863 ReactCompositeComponentMixin._performComponentUpdatereact.js:6783 ReactCompositeComponentMixin.updateComponentreact.js:13371 ReactPerf.measure.wrapperreact.js:6647 ReactCompositeComponentMixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:4779 ReactChildReconciler.updateChildrenreact.js:12900 ReactMultiChild.Mixin._updateChildrenreact.js:12874 ReactMultiChild.Mixin.updateChildrenreact.js:7862 ReactDOMComponent.Mixin._updateDOMChildrenreact.js:7713 ReactDOMComponent.Mixin.updateComponentreact.js:7697 ReactDOMComponent.Mixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:6884 ReactCompositeComponentMixin._updateRenderedComponentreact.js:6863 ReactCompositeComponentMixin._performComponentUpdatereact.js:6783 ReactCompositeComponentMixin.updateComponentreact.js:13371 ReactPerf.measure.wrapperreact.js:6647 ReactCompositeComponentMixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:6884 ReactCompositeComponentMixin._updateRenderedComponentreact.js:6863 ReactCompositeComponentMixin._performComponentUpdatereact.js:6783 ReactCompositeComponentMixin.updateComponentreact.js:13371 ReactPerf.measure.wrapperreact.js:6647 ReactCompositeComponentMixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:4779 ReactChildReconciler.updateChildrenreact.js:12900 ReactMultiChild.Mixin._updateChildrenreact.js:12874 ReactMultiChild.Mixin.updateChildrenreact.js:7862 ReactDOMComponent.Mixin._updateDOMChildrenreact.js:7713 ReactDOMComponent.Mixin.updateComponentreact.js:7697 ReactDOMComponent.Mixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:6884 ReactCompositeComponentMixin._updateRenderedComponentreact.js:6863 ReactCompositeComponentMixin._performComponentUpdatereact.js:6783 ReactCompositeComponentMixin.updateComponentreact.js:13371 ReactPerf.measure.wrapperreact.js:6647 ReactCompositeComponentMixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:4779 ReactChildReconciler.updateChildrenreact.js:12900 ReactMultiChild.Mixin._updateChildrenreact.js:12874 ReactMultiChild.Mixin.updateChildrenreact.js:7862 ReactDOMComponent.Mixin._updateDOMChildrenreact.js:7713 ReactDOMComponent.Mixin.updateComponentreact.js:7697 ReactDOMComponent.Mixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:6884 ReactCompositeComponentMixin._updateRenderedComponentreact.js:6863 ReactCompositeComponentMixin._performComponentUpdatereact.js:6783 ReactCompositeComponentMixin.updateComponentreact.js:13371 ReactPerf.measure.wrapperreact.js:6647 ReactCompositeComponentMixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:4779 ReactChildReconciler.updateChildrenreact.js:12900 ReactMultiChild.Mixin._updateChildrenreact.js:12874 ReactMultiChild.Mixin.updateChildrenreact.js:7862 ReactDOMComponent.Mixin._updateDOMChildrenreact.js:7713 ReactDOMComponent.Mixin.updateComponentreact.js:7697 ReactDOMComponent.Mixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:6884 ReactCompositeComponentMixin._updateRenderedComponentreact.js:6863 ReactCompositeComponentMixin._performComponentUpdatereact.js:6783 ReactCompositeComponentMixin.updateComponentreact.js:13371 ReactPerf.measure.wrapperreact.js:6647 ReactCompositeComponentMixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:4779 ReactChildReconciler.updateChildrenreact.js:12900 ReactMultiChild.Mixin._updateChildrenreact.js:12874 ReactMultiChild.Mixin.updateChildrenreact.js:7862 ReactDOMComponent.Mixin._updateDOMChildrenreact.js:7713 ReactDOMComponent.Mixin.updateComponentreact.js:7697 ReactDOMComponent.Mixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:6884 ReactCompositeComponentMixin._updateRenderedComponentreact.js:6863 ReactCompositeComponentMixin._performComponentUpdatereact.js:6783 ReactCompositeComponentMixin.updateComponentreact.js:13371 ReactPerf.measure.wrapperreact.js:6647 ReactCompositeComponentMixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:4779 ReactChildReconciler.updateChildrenreact.js:12900 ReactMultiChild.Mixin._updateChildrenreact.js:12874 ReactMultiChild.Mixin.updateChildrenreact.js:7862 ReactDOMComponent.Mixin._updateDOMChildrenreact.js:7713 ReactDOMComponent.Mixin.updateComponentreact.js:7697 ReactDOMComponent.Mixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:6884 ReactCompositeComponentMixin._updateRenderedComponentreact.js:6863 ReactCompositeComponentMixin._performComponentUpdatereact.js:6783 ReactCompositeComponentMixin.updateComponentreact.js:13371 ReactPerf.measure.wrapperreact.js:6647 ReactCompositeComponentMixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:4779 ReactChildReconciler.updateChildrenreact.js:12900 ReactMultiChild.Mixin._updateChildrenreact.js:12874 ReactMultiChild.Mixin.updateChildrenreact.js:7862 ReactDOMComponent.Mixin._updateDOMChildrenreact.js:7713 ReactDOMComponent.Mixin.updateComponentreact.js:7697 ReactDOMComponent.Mixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:6884 ReactCompositeComponentMixin._updateRenderedComponentreact.js:6863 ReactCompositeComponentMixin._performComponentUpdatereact.js:6783 ReactCompositeComponentMixin.updateComponentreact.js:13371 ReactPerf.measure.wrapperreact.js:6647 ReactCompositeComponentMixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:4779 ReactChildReconciler.updateChildrenreact.js:12900 ReactMultiChild.Mixin._updateChildrenreact.js:12874 ReactMultiChild.Mixin.updateChildrenreact.js:7862 ReactDOMComponent.Mixin._updateDOMChildrenreact.js:7713 ReactDOMComponent.Mixin.updateComponentreact.js:7697 ReactDOMComponent.Mixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:6884 ReactCompositeComponentMixin._updateRenderedComponentreact.js:6863 ReactCompositeComponentMixin._performComponentUpdatereact.js:6783 ReactCompositeComponentMixin.updateComponentreact.js:13371 ReactPerf.measure.wrapperreact.js:6647 ReactCompositeComponentMixin.receiveComponentreact.js:14131 ReactReconciler.receiveComponentreact.js:6884 ReactCompositeComponentMixin._updateRenderedComponentreact.js:6863 ReactCompositeComponentMixin._performComponentUpdatereact.js:6783 ReactCompositeComponentMixin.updateComponentreact.js:13371 ReactPerf.measure.wrapperreact.js:6680 ReactCompositeComponentMixin.performUpdateIfNecessaryreact.js:14149 ReactReconciler.performUpdateIfNecessaryreact.js:14899 runBatchedUpdatesreact.js:16625 Mixin.performreact.js:16625 Mixin.performreact.js:14843 assign.performreact.js:14923 flushBatchedUpdatesreact.js:13371 ReactPerf.measure.wrapperreact.js:16698 Mixin.closeAllreact.js:16639 Mixin.performreact.js:9143 ReactDefaultBatchingStrategy.batchedUpdatesreact.js:14963 enqueueUpdatereact.js:14481 enqueueUpdatereact.js:14604 ReactUpdateQueue.enqueueForceUpdatereact.js:6008 ReactComponent.forceUpdatepaper.js:392 window.components.papers.paper.React.createClass.reciverElementrequests.js:517 window.requests._transferCompleterequests.js:140 request.onreadystatechange\r\n\r\nwhat's that mean?"},"comment":{"url":"https://api.github.com/repos/facebook/react/issues/comments/90135331","html_url":"https://github.com/facebook/react/issues/3585#issuecomment-90135331","issue_url":"https://api.github.com/repos/facebook/react/issues/3585","id":90135331,"user":{"login":"zpao","id":8445,"avatar_url":"https://avatars.githubusercontent.com/u/8445?v=3","gravatar_id":"","url":"https://api.github.com/users/zpao","html_url":"https://github.com/zpao","followers_url":"https://api.github.com/users/zpao/followers","following_url":"https://api.github.com/users/zpao/following{/other_user}","gists_url":"https://api.github.com/users/zpao/gists{/gist_id}","starred_url":"https://api.github.com/users/zpao/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/zpao/subscriptions","organizations_url":"https://api.github.com/users/zpao/orgs","repos_url":"https://api.github.com/users/zpao/repos","events_url":"https://api.github.com/users/zpao/events{/privacy}","received_events_url":"https://api.github.com/users/zpao/received_events","type":"User","site_admin":false},"created_at":"2015-04-06T16:33:32Z","updated_at":"2015-04-06T16:33:32Z","body":"It's really hard to say for sure without more info but one thing that jumps out at me is that you're doing some AJAX and calling `forceUpdate` with the result. It's possible that the component unmounted before you did that though. In 0.12, doing that would throw an error. In 0.13 I think we should just be warning and then just returning. Clearing the requests in `componentDidMount` is the suggested way of handling this.\r\n\r\nYour error is suggesting you're using 0.13 though. If you could reduce this to something reproducible and sharable, that would be helpful."}}