Hello!

I'm running into an issue when automatically upgrading activeadmin through renovate.

I'm running

#Gemfile
gem 'activeadmin', '4.0.0.beta13'

and

// package.json
{
  "dependencies": {
    "@activeadmin/activeadmin": "4.0.0.beta13"
  }
}

Now, when I want to have renovate upgrade this repository, I get the following upgrades:

• activeadmin gem to v4.0.0.beta15 (current at the time of writing this)
• @activeadmin/activeadmin npm to v4.0.0.beta9 (I'd expect v4.0.0.beta15!)

You might ask: tell the renovate folks! Well... Nay.

NPM wants us developers to strictly adhere to semver 2.0, which says about prerelease identifiers that they should look like e.g. v4.0.0.beta.1 (note the additional .)

Alphanumerical parts are to be compared lexically, while numeric-only parts are compared numerically.

This means that "alpha9" > "alpha11" because of the lexical comparison. While "alpha.9" < "alpha.11", as the parts are separately compared.

My request would thus be to change pre-release versioning to adhere to semver 2.0 spec and thus release versions like 4.0.0.alpha.16

rubygems does not enforce this and thus uses a more relaxed comparison, which should also work with the proposed scheme