How to overwrite incorrect TypeScript type definition installed via @types/package

Question

Say that I want to use dotenv module in my TypeScript project and install its .d.ts using npm install @types/dotenv --save. Then I realize that the types are not correct. For example, the config() function doesn't return boolean but a richer object.

How do I deal with this situation? Should I just copy the downloaded type definition to another file, update it manually and uninstall @types/dotenv? Is there a better way? (I need the fix right away, not after it has been merged by upstream maintainers.)

Answer 1

You can patch @types/foo locally for your app by patch-package.

1. Run npm i -D patch-package

2. Simply modify node_modules/@types/foo to suit your needs.

3. Run npx patch-package @types/foo. This creates a diff file in patches/ that records the changes made from the last step.

4. Add "scripts": {"postinstall": "patch-package"} in package.json. This make patches to be applied each time people run npm install.