Specifying latest version with Lerna monorepos

[edmorley]

Hi!

We use Lerna with our monorepo. As such the repo root package.json does not contain a version property, and instead the packages live under packages/* thanks to Yarn's workspaces feature.

This means that we cannot pass --package to auto-changelog, otherwise we get the following error:
auto-changelog: Generating changelog…TypeError: Invalid Version: vundefined

As a workaround, we're planning on using something like this:
auto-changelog --latest-version $(jq -r .version lerna.json)

...however I was wondering whether this is something that you'd be open to auto-changelog supporting? (If only because using bash subcommands makes the package.json script not compatible with Windows.)

Possible options:

• the --package option accepting arguments, so that we could pass --package lerna.json (since it also happens to contain a version property) or --package packages/neutrino/package.json
• the --package option automatically falling back to other locations, if there is no version in that file (eg it could scan the workspace directories, or know to try lerna.json)
• adding a --lerna-version option that specifically uses lerna.json

Thoughts? (I'm happy to open a PR if/when a design direction is agreed :-))

CC @eliperelman

[ljharb]

I think you need a version in the root package.json regardless, or npm will complain too. Just set private true and there’s no risk of publishing.

[edmorley]

We use yarn, which I don't think minds. That said, I'd be happy to add a version to the root file, but my understanding was that lerna does not update it, which means we have to manually sync it (or add another custom script).

[ljharb]

You wouldn’t have to - you can leave it at 0.0.0 forever.

[edmorley]

That would fix the error when running auto-changelog --package, however then the changes for the about-to-be-released version are not included in the README. (The pupose of --package or --latest-version is to be able to tell auto-changelog what the new version number is, since at that point in the release process the package and/or git tag does not exist for it to be able to infer itself.)

[cookpete]

@edmorley I've added support for --package [file] in 1.13.0. Let me know if this solves your issue.

[edmorley]

That works great - thank you! :-)