feat(no-unstable-default-props): add safeDefaultProps option, closes #1312

[christopher-buss]

What kind of change does this PR introduce?

• Bugfix
• Feature
• Docs
• Test
• New Binding issue #___
• Code style update
• Refactor
• Build-related changes
• Other, please describe:

Does this PR introduce a breaking change?

• Yes, and the changes were approved in issue #___
• No

Checklist

• When resolving issues, they are referenced in the PR's title (e.g fix: remove a typo, closes #___, #___)
• I have added a convincing reason for adding this feature, if necessary

Other information

Summary

Implements the safeDefaultProps option for the no-unstable-default-props rule to allow listing framework-specific value-type constructors and factory methods that are safe to use in default props.

Testing

• Added 6 new valid test cases covering the new option functionality
• Added 3 new invalid test cases ensuring non-allowlisted items still fail
• Total: 32 tests for this rule (up from 28)
• Full suite: All 2809 tests pass with no regressions
• Backward compatible: default behavior unchanged when option not set

Examples

// ✅ Allowed with safeDefaultProps: ["Vector3"]
function MyComponent({ position = new Vector3(0, 0, 0) }) {
  return <div />;
}

// ❌ Still fails - not in allowlist
function MyComponent({ obj = {} }) {
  return <div />;
}

Configuration

{
  "@eslint-react/no-unstable-default-props": ["error", {
    "safeDefaultProps": ["Vector3", "vector", "Color3", "/^Immutable.*/"]
  }]
}

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Project	Deployment	Preview	Comments	Updated (UTC)
eslint-react	Ready	Preview	Comment	Nov 9, 2025 11:17pm

[Rel1cx]

LGTM.