What would cause lockfileVersion in package-lock.json to decrease by one?

Question

Bumped the patch version in a package.json (manually, edited file). Noted that the lock file had the old version, so I did an npm install to update it. When I did that the lockfileVersion field went from 2 to 1. This seems odd. The docs about lockfileVersion:

An integer version, starting at 1 with the version number of this document whose semantics were used when generating this package-lock.json.

Well that didn't help. So is this change in values of the version a concern? It seems like an odd change, for it to decrease like that. Should I not update the lockfile when I bump the version?

Node v12.16.1, NPM 6.14.10

Answer 1

https://docs.npmjs.com/cli/v8/configuring-npm/package-lock-json#lockfileversion

lockfileversion 2 is NPM 7. So one person on my team was using NPM 7 while I was still on 6 (lockfileversion 1).

Answer 2

It's probably just because you used an older npm version than the one that was used the last time the package-lock.json file was changed. Update your npm executable and it should use a greater or equal lockfileVersion now.