Dynamically generate/detect mod version

[MattSturgeon]

Currently we set the mod version in gradle.properties and bump this value before doing a new release.

It may be useful to generate it instead, potentially reducing release friction and opening the door to "snapshot" builds, etc.

This may not be something you actually want; manually defining the version inherently comes with more control and less complexity. Feel free to label this issue wontfix.

Implementation

The algorithm would be something along the lines of:

• Get some data from git;
  • Most recent ancestor tag (filtered by regex)
  • Number of commits since tag
  • Current branch name
  • Is the working directory clean or dirty
• If 0 commits since tag, and the dir is clean, this is a release version
  • Handle if the commit has multiple tags; try to find the "version" tag
  • Set project.version to the tag
• Otherwise, this is a "snapshot" build
  • Maybe do something like latest_tag+commit_count+dirty?

Complications

Simply implementing the above would kinda break patchChangelog, since it uses mod_version to determine what version to mark the "unreleased" changes as belonging to. Therefore we couldn't patch the changelog until after tagging the release commit, meaning we'd have to --amend it.

Probably the best way to avoid this would be three separate gradle tasks:

• bumpMajorVersion: ++x.0.0
• bumpMinorVersion: x.++y.0
• bumpPatchVersion: x.y.++z

Running any of these tasks would detect the previous release, bump project.version, patch the changelog, commit & tag.

The release process would then become:

1. Run gradlew bumpPatchVersion
2. Run git push to push the new commit to the remote branch
3. Run git push --tags or git push origin <tagname> to push the tags

These bumping tasks could still be added even without dynamic versions, but I'm mentioning them here as they solve the changlog patching issue.