react

Instruction file imported from siriwatknp/jun-mvp-starter (.cursor/rules/react.mdc). Copyright stays with the author.

Creating UI state

• Always start with useState hook.
• Use primitive values as much as possible, avoid using object.
• If there are better approach to create the state for a specific circumstance, ask first and provide the why with detail explanation.
• Avoiding overuse of useEffect, try to find alternatives first. For example, moving to useState initialization if possible.

React context

• When passing functions through context, make sure that it's wrapped with useCallback.
• When passing object through context, make sure that it's wrapped with useMemo.

Component

Prefer using function directly instead of creating new function inside components. Here are examples that you should NOT do:

• simple event handlers

function Component({ onClick }) {

  function handleClick() {
    onClick?.()
  }
  
  return <button onClick={handleClick}>...</button>
}

• simple render

function Component() {
  const renderIcon = () => <svg>...</svg>;
  return <div>{renderIcon()}</div>;
}

If the component is a pure component, spread the props to the root element. For example, a LoginButton:

function LoginButton({ size, icon, children, ...props }) {
  return (
    <button {...props}>
      {icon} <span>{children}</span>
    </button>
  );
}

TypeScript

• Prefer interface over type if possible for component props
• For props spread to the root element, include JSX.intrinsicElement of the root element too.
• Write the description/purpose above each field of the type.