Is that possible? I thought the lock files restricted to a specific version with an integrity check hash. Is it possible that it would install a newer version which doesn't match the hash in the lock file? Do they just mean package.json here?
Well, for one, the behavior is somewhat insane.
`npm install` with no additional arguments does update the lockfile if your package.json and your lockfile are out of sync with one another for any reason, and so to get a guarantee that it doesn't change your lockfile, you must do additional configuration or guarantee by some external mechanism that you don't ever have an out of date package.json and lock. For this reason alone, the advice of "just don't use npm install, use npm ci instead" is still extremely valid, you'd really like this to fail fast if you get out of sync.
`npm install additional-package` also updates your lock file. Other package managers distinguish these two operations, with the one to add a new dependency being called "add" instead of "install".
The docs add to the confusion. https://docs.npmjs.com/cli/v11/commands/npm-install#save suggests that writing to package-lock.json is the default and you need to change configuration to disable it. The notion that it won't change your lock file if you're already in sync between package.json and package-lock.json is not actually spelled out clearly anywhere on the page.
> At least not anymore.
You've partially answered your own question here.
Is that the case? If it were ever true (outside of outright bugs in npm), it must have been many many years and major npm releases ago. So that doesn't justify brigading outdated information.
However in rare cases where I am forced to use it to contribute to some npm-using project, I have noticed that the lockfile often gets updated and I get a huge diff even though I didn't edit the dependencies. So I've always assumed that was the same issue with npm ignoring the lockfile, but maybe it's some other issue? idk
> Do they just mean package.json here?
Yes, most likely. A package-lock.json always specifies an exact version with hash and not a "version X or newer".
This comes up every time npm install is discussed. Yes, npm install will "ignore" your lockfile and install the latest dependancies it can that satisfy the constraints of your package.json. Yes, you should use npm clean-install. One shortcoming is the implementation insists on deleteing the entire node_modules folder, so package installs can actually take quite a bit of time, even when all the packages are being served from the npm disk cache: https://github.com/npm/cli/issues/564