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`setState` mutates state instead of replacing it

See original GitHub issue

Currently in Preact 8.2.9, Component.prototype.setState mutates the previous state instead of replacing it with a patched version. This is unnecessarily inconsistent with React, can break user intuitions, can break things ported from React, and makes the second argument to shouldComponentUpdate useless and misleading.

I discovered this the hard way when sharing an initial state constant between components, assuming it would be treated as immutable. As previously mentioned, this can break user intuitions when coming from React.

Can we fix this? I would be willing to do a PR.

Issue Analytics

  • State:closed
  • Created 5 years ago
  • Reactions:2
  • Comments:6 (5 by maintainers)

github_iconTop GitHub Comments

1reaction
KevinDoughtycommented, Jul 26, 2018

Oh I guess someone beat me to it, with issue 1170.

0reactions
developitcommented, Aug 5, 2018

This should be fixed in 8.3.0! Please feel free to re-open otherwise 😃

Read more comments on GitHub >

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