How to find dead code in a large react project?

First of all, very good question, in large project coders usually try many lines of code test and at the end of result, hard to find the unused code.

There is two possible that must be work for you - i usually do whenever i need to remove and reduce the unused code into my project.

1st way WebStorm IDE:

If you're using the web-storm IDE for JS development or React JS / React Native or Vue js etc it's tell us and indicate us alote of mention with different color or red warning as unused code inside the editor

but it's not works in your particular scenario there is another way to remove the unused code .

2nd Way unrequired Library:

The second way to remove the unused code inside the project is unrequired library you can visit here : unrequired github

another library called depcheck under NPM & github here

Just follow their appropriate method - how to use them you will fix this unused issue easily

Hopefully that helps you

Solution:

For node projects, run the following command in your project root:

npx unimported

If you're using flow type annotations, you need to add the --flow flag:

npx unimported --flow

Source & docs: https://github.com/smeijer/unimported

Outcome:

Background

Just like the other answers, I've tried a lot of different libraries but never had real success.

I needed to find entire files that aren't being used. Not just functions or variables. For that, I already have my linter.

I've tried deadfile, unrequired, trucker, but all without success.

After searching for over a year, there was one thing left to do. Write something myself.

unimported starts at your entry point, and follows all your import/require statements. All code files that exist in your source folder, that aren't imported, are being reported.

Note, at this moment it only scans for source files. Not for images or other assets. As those are often "imported" in other ways (through tags or via css).

Also, it will have false positives. For example; sometimes we write scripts that are meant to simplify our development process, such as build steps. Those aren't directly imported.

Also, sometimes we install peer dependencies and our code doesn't directly import those. Those will be reported.

But for me, unimported is already very useful. I've removed a dozen of files from my projects. So it's definitely worth a shot.

If you have any troubles with it, please let me know. Trough github issues, or contact me on twitter: https://twitter.com/meijer_s