how to convert package-lock.json to yarn.lock?

You can use yarn import to generate yarn.lock file from an existing npm-installed node_modules folder.

yarn import aims to alleviate this challenge by generating a yarn.lock file in one of two ways:

1. Using the dependency tree in an existing package-lock.json file created by npm install
2. If no such file exists, using the versions found inside node_modules according to normal require.resolve() resolution rules.

For example:

☁  api [develop] ⚡  yarn import   
yarn import v1.17.3
info found npm package-lock.json, converting to yarn.lock
warning jest > jest-cli > jest-config > jest-environment-jsdom > jsdom > [email protected]: use String.prototype.padStart()
success Saved lockfile.
✨  Done in 21.56s.

You can use the tool synp to convert back and forth:

synp --source-file yarn.lock            # will create package-lock.json
synp --source-file package-lock.json    # will create yarn.lock