{"componentChunkName":"component---src-templates-blog-js","path":"/blog/2014/02/20/react-v0.9.html","result":{"data":{"markdownRemark":{"html":"

I’m excited to announce that today we’re releasing React v0.9, which incorporates many bug fixes and several new features since the last release. This release contains almost four months of work, including over 800 commits from over 70 committers!

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Thanks to everyone who tested the release candidate; we were able to find and fix an error in the event handling code, we upgraded envify to make running browserify on React faster, and we added support for five new attributes.

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As always, the release is available for download from the CDN:

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We’ve also published version 0.9.0 of the react and react-tools packages on npm and the react package on bower.

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What’s New?

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This version includes better support for normalizing event properties across all supported browsers so that you need to worry even less about cross-browser differences. We’ve also made many improvements to error messages and have refactored the core to never rethrow errors, so stack traces are more accurate and Chrome’s purple break-on-error stop sign now works properly.

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We’ve also added to the add-ons build React.addons.TestUtils, a set of new utilities to help you write unit tests for React components. You can now simulate events on your components, and several helpers are provided to help make assertions about the rendered DOM tree.

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We’ve also made several other improvements and a few breaking changes; the full changelog is provided below.

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JSX Whitespace

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In addition to the changes to React core listed below, we’ve made a small change to the way JSX interprets whitespace to make things more consistent. With this release, space between two components on the same line will be preserved, while a newline separating a text node from a tag will be eliminated in the output. Consider the code:

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<div>\n  Monkeys:\n  {listOfMonkeys} {submitButton}\n</div>
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In v0.8 and below, it was transformed to the following:

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React.DOM.div(null,\n  \" Monkeys: \",\n  listOfMonkeys, submitButton\n)
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In v0.9, it will be transformed to this JS instead:

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React.DOM.div(null,\n  \"Monkeys:\",  listOfMonkeys, \" \", submitButton)
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We believe this new behavior is more helpful and eliminates cases where unwanted whitespace was previously added.

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In cases where you want to preserve the space adjacent to a newline, you can write {'Monkeys: '} or Monkeys:{' '} in your JSX source. We’ve included a script to do an automated codemod of your JSX source tree that preserves the old whitespace behavior by adding and removing spaces appropriately. You can install jsx_whitespace_transformer from npm and run it over your source tree to modify files in place. The transformed JSX files will preserve your code’s existing whitespace behavior.

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Changelog

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React Core

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Breaking Changes

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New Features

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Bug Fixes

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React with Addons

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JSX Compiler and react-tools Package

\n","excerpt":"I’m excited to announce that today we’re releasing React v0.9, which incorporates many bug fixes and several new features since the last release. This release contains almost four months of work, including over 800 commits from over 70 committers! Thanks to everyone who tested the release candidate; we were able to find and fix an error in the event handling code, we upgraded envify to make running browserify on React faster, and we added support for five new attributes. As always, the release…","frontmatter":{"title":"React v0.9","next":null,"prev":null,"author":[{"frontmatter":{"name":"Sophie Alpert","url":"https://sophiebits.com/"}}]},"fields":{"date":"February 20, 2014","path":"content/blog/2014-02-20-react-v0.9.md","slug":"/blog/2014/02/20/react-v0.9.html"}},"allMarkdownRemark":{"edges":[{"node":{"frontmatter":{"title":"Introducing the New JSX Transform"},"fields":{"slug":"/blog/2020/09/22/introducing-the-new-jsx-transform.html"}}},{"node":{"frontmatter":{"title":"React v17.0 Release Candidate: No New Features"},"fields":{"slug":"/blog/2020/08/10/react-v17-rc.html"}}},{"node":{"frontmatter":{"title":"React v16.13.0"},"fields":{"slug":"/blog/2020/02/26/react-v16.13.0.html"}}},{"node":{"frontmatter":{"title":"Building Great User Experiences with Concurrent Mode and Suspense"},"fields":{"slug":"/blog/2019/11/06/building-great-user-experiences-with-concurrent-mode-and-suspense.html"}}},{"node":{"frontmatter":{"title":"Preparing for the Future with React Prereleases"},"fields":{"slug":"/blog/2019/10/22/react-release-channels.html"}}},{"node":{"frontmatter":{"title":"Introducing the New React DevTools"},"fields":{"slug":"/blog/2019/08/15/new-react-devtools.html"}}},{"node":{"frontmatter":{"title":"React v16.9.0 and the Roadmap Update"},"fields":{"slug":"/blog/2019/08/08/react-v16.9.0.html"}}},{"node":{"frontmatter":{"title":"Is React Translated Yet? ¡Sí! Sim! はい！"},"fields":{"slug":"/blog/2019/02/23/is-react-translated-yet.html"}}},{"node":{"frontmatter":{"title":"React v16.8: The One With Hooks"},"fields":{"slug":"/blog/2019/02/06/react-v16.8.0.html"}}},{"node":{"frontmatter":{"title":"React v16.7: No, This Is Not the One With Hooks"},"fields":{"slug":"/blog/2018/12/19/react-v-16-7.html"}}}]}},"pageContext":{"slug":"/blog/2014/02/20/react-v0.9.html"}},"staticQueryHashes":[]}