docs(linter): document intentional exclusion of ignoreCase option in jsx-no-duplicate-props

[Copilot]

The react/jsx-no-duplicate-props rule was missing documentation about the intentionally unsupported ignoreCase option from ESLint, causing confusion for users migrating from ESLint configurations (e.g., Airbnb preset).

Changes

• Added "Differences from ESLint" section documenting that ignoreCase is not supported
• Clarified that props with different cases (e.g., foo and Foo) are treated as distinct, which is correct behavior since JSX props are case-sensitive

The rule already implements case-sensitive prop checking (as evidenced by existing test cases like <App A a /> passing). This change only adds documentation to make the intentional design decision explicit.

Original prompt

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This section details on the original issue you should resolve

<issue_title>linter: react/jsx-no-duplicate-props rule lacks ignoreCase option</issue_title>
<issue_description>### What version of Oxlint are you using?

0.33.0

What command did you run?

oxlint

What does your .oxlintrc.json config file look like?

{
  "$schema": "./node_modules/oxlint/configuration_schema.json",
  "plugins": [
    "react"
  ],
  "rules": {
    "react/jsx-no-duplicate-props": ["error", { "ignoreCase": true }],
  }
}

What happened?

See the docs for the original rule: https://github.com/jsx-eslint/eslint-plugin-react/blob/master/docs/rules/jsx-no-duplicate-props.md

The oxc rule has no ignoreCase config option.

I assume this was a mistake caused by the @eslint-react/eslint-plugin plugin having the same rule but lacking ignoreCase? But ignoreCase should be supported, otherwise the implementation differs. The widely-used eslint airbnb config sets this option explicitly, which is how I noticed the problem after trying to migrate an ESLint config.

ignoreCase should default to false.

Alt implementation which has no ignoreCase option:

• https://www.eslint-react.xyz/docs/rules/jsx-no-duplicate-props
• https://github.com/Rel1cx/eslint-react</issue_description>

<agent_instructions>See the most recent comment </agent_instructions>

Comments on the Issue (you are @copilot in this section)

@camc314 I'm really tempted to say we just shouldn't support this. Props with different case are different, so why does an `ignoreCase` option make sense.

biome also doesn't support this option</comment_new>
<comment_new>@connorshea

I'm really tempted to say we just shouldn't support this. Props with different case are different, so why does an ignoreCase option make sense.

biome also doesn't support this option

Honestly, that's very fair. I think it probably makes sense to exclude this option. The only reason I noticed it was because the airbnb config is used for eslint at work and so I ran into one case where we disabled the rule with a disable-directive because of it. I have no idea why the airbnb config was set up with this config option set to true, but it was.

We should probably note in the docs that we are intentionally excluding it, though.</comment_new>
<comment_new>@camc314
@copilot add docs to mention that we explicitly don't support this option</comment_new>

• Fixes linter: react/jsx-no-duplicate-props rule lacks ignoreCase option #16968

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Pull request overview

This PR adds documentation to clarify the intentional exclusion of the ignoreCase option from the react/jsx-no-duplicate-props rule, addressing user confusion when migrating from ESLint configurations.

• Added a "Differences from eslint-plugin-react" documentation section
• Clarified that props with different cases are treated as distinct (case-sensitive behavior)
• Explained that this design decision is intentional since JSX props are inherently case-sensitive

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