What is the purpose of the 'defaultProps' property in a React component?

0-2 years experience

1. 1How would you add a defaultProps object to a functional component that receives a 'title' prop?
2. 2If a parent component omits a prop that you defined in defaultProps, what will the child component receive?

2-5 years experience

1. 1We migrated a class component that used defaultProps to a function component with hooks, but the defaults stopped working. How would you investigate and fix the issue?
2. 2Why might destructuring props in the function signature cause defaultProps to be ignored, and how can you work around it?

5-8 years experience

1. 1When building a shared component library, would you prefer defaultProps or default parameters for setting defaults, considering tree‑shaking and TypeScript support? Explain your reasoning.
2. 2Discuss any performance or bundle‑size implications of relying on defaultProps in a server‑side rendered React app.

8+ years experience

1. 1Our legacy codebase heavily uses defaultProps in class components, but we’re moving to a fully typed functional architecture across several teams. What migration strategy would you propose to replace defaultProps while minimizing breakage?
2. 2How would you set up linting or codemod tooling to enforce a consistent approach to default values across a monorepo that contains both JavaScript and TypeScript React components?