react-doctor/no-default-props

React 19 removes `Component.defaultProps` for function components. Move the defaults into the destructured props parameter: `function Foo({ size = "md", variant = "primary" })` instead of `Foo.defaultProps = { size: "md", variant: "primary" }`.

• Category: Architecture
• Severity: warn
• Source: oxlint-plugin-react-doctor
• Framework: global
• Enabled when: always

Validation prompt

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Fires on any UppercaseIdentifier.defaultProps = {...} assignment (the rule keys off the uppercase first letter of the left-hand object, skipping computed access like Foo['defaultProps']). It cannot tell class from function components from the assignment alone, so confirm the target is an actual React component rather than an unrelated object that coincidentally has a defaultProps property.

Fix prompt

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Delete the Foo.defaultProps = {...} statement and inline each default into the destructured props parameter, e.g. function Foo({ size = "md", variant = "primary" }). In TypeScript, mark those props optional (size?: "md" | "lg"). For class components, switch to JavaScript class field defaults on a destructured props read or migrate to a function component. See https://react.dev/blog/2024/12/05/react-19#removed-proptypes-and-defaultprops

Related rules

More Architecture rules from the rules reference:

• react-doctor/no-generic-handler-names: Rename to describe the action: e.g. `handleSubmit` → `saveUserProfile`, `handleClick` → `toggleSidebar`
• react-doctor/no-giant-component: Extract logical sections into focused components: `<UserHeader />`, `<UserActions />`, etc.
• react-doctor/no-gradient-text: Use solid text colors for readability. If you need emphasis, use font weight, size, or a distinct color instead of gradients
• react-doctor/no-inline-exhaustive-style: Move styles to a CSS class, CSS module, Tailwind utilities, or a styled component — inline objects with many properties hurt readability and create new references every render
• react-doctor/no-many-boolean-props: Split into compound components or named variants: `<Button.Primary />`, `<DialogConfirm />` instead of stacking `isPrimary`, `isConfirm` flags