the opposite of .gitignore, whitelist

I have a good idea, add a file to git that is the opposite of .gitignore, whitelist, the code in the development directory can be submitted to git version control, you can only submit the source code in the src directory, without concern for development tools and operations.System and other files, after all, the type of each project code is fixed, I am in the community I did not find a way to submit requirements in the community, so
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lhf635@163.com