mui / mui/material-ui

Don's mutate the theme object in ThemeProvider.

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#33,242 2 comments 1 reaction 0 assignees View on GitHub

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customization: theme scope: all components type: bug
Dominant language
JavaScript
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Description

Duplicates
  • I have searched the existing issues
Latest version
  • I have tested the latest version
Current behavior 😯

ThemeProvider try adding a property Symbol( mui.nested ) to the original theme object.

https://github.com/mui/material-ui/blob/7c75acec84879d013ae8e68ff319baf9fef1045e/packages/mui-private-theming/src/ThemeProvider/ThemeProvider.js#L58

It causes error while using some state management libraries, such a Recoil, to manage theme objects, because the libraries may freeze objects they are handling, then Error Object is not extensible will be thrown.

On the other hand, changing origin object will also cause other side effects.

Expected behavior 🤔

Don't change the original object.

Steps to reproduce 🕹

Steps:

Context 🔦

No response

Your environment 🌎
npx @mui/envinfo
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  Output from `npx @mui/envinfo` goes here.

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start in packages/mui-private-theming/src/ThemeProvider/ThemeProvider.js at the linked line where the nested theme property is added. Check how ThemeProvider handles the incoming theme object and verify the change preserves frozen or otherwise non-extensible themes without mutating the original object.

Written by the indexing model from the issue text.

Assessment

Tech stack
javascript, react
Domain
frontend
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Clearly specified
Newbie friendliness
45/100

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