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Deprecated lifecycle method warnings with React 16.9

See original GitHub issue

The following warning is shown upon upgrading to React 16.9.0:

    Error: Warning: componentWillMount has been renamed, and is not recommended for use. See https://fb.me/react-async-component-lifecycle-hooks for details.
    
    * Move code with side effects to componentDidMount, and set initial state in the constructor.
    * Rename componentWillMount to UNSAFE_componentWillMount to suppress this warning in non-strict mode. In React 17.x, only the UNSAFE_ name will work. To rename all deprecated lifecycles to their new names, you can run `npx react-codemod rename-unsafe-lifecycles` in your project source folder.
    
    Please update the following components: Select in src/tests.entry.js (line 294578)

Issue Analytics

State:
Created 4 years ago
Reactions:121
Comments:31 (7 by maintainers)

Top GitHub Comments

198reactions

jairusdcommented, Aug 12, 2019

oh sorry guys i was drunk when i made that comment

37reactions

jairusdcommented, Aug 11, 2019

That means you have component using legacy lifecycle OR you are using a library which uses the legacy lifecycle, I don’t see this as an issue, in fact, it is helpful to identify legacy code and warn you when you do use libraries that do still.

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