Versioning System and Repository Branch Layout

With the release for beta we’ve moved the SpongeAPI versioning to semantic versioning (see https://semver.org/). This change means that every time that we make a release we have to increment the version according to the rules of semver.

SemVer

SemVer uses the scheme X.Y.Z, where X is a major version, Y is a minor one and Z finally is a patch version. A release containing changes which are not backwards-compatible must be one major version ahead of the previous release. If there are only new features that are still backwards compatible, then the new release will be one minor version ahead of the previous release, and if the release strictly contains bugfixes then only the patch version will be incremented.

This means that for example 3.2.0 is fully compatible to 3.0.0 while 4.0.0 isn’t binary compatible to 3.0.0. 3.1.0 and 3.1.2 are fully interchangeable besides the bugs that were fixed.

The layout of our branches (described below) is designed to assist this process by allowing us to make minor releases without a breaking change forcing us to make it a major release. This branch layout applies to the SpongeAPI, SpongeCommon, SpongeForge, and SpongeVanilla repositories but not to the SpongeDocs.

SpongeAPI, SpongeCommon, SpongeForge and SpongeVanilla

The Bleeding Branch

The core of our repositories is the bleeding branch. Almost all changes will be added to bleeding, including new features, changes, and bugfixes. The version of bleeding will always be the next major release version appended with -SNAPSHOT (eg 6.0.0-SNAPSHOT) to denote that it is not yet a final build and subject to change.

The primary reason for having the bleeding branch is to have a testing ground for changes. Even experienced members of the Sponge team can accidentally cause a build to fail or miss a bug. The bleeding branch will be tested by people in the community that want the very latest, and it means that we can fix bugs that arise far more readily.

Stable Branches

Stable branches represent a much more stable platform which plugins and server implementations can be built upon. There will be no breakages to API, only non-breaking additions. There is a branch named after each major API release, which contains the latest API/implementation for that release including any minor or patch releases.

When the time comes to release a major version, a new stable-x branch will be created from bleeding, where x is the new major version - for example, stable-5. bleeding will be appropriately updated to be the next major release as described above.

Changes that have been in bleeding for a while, which have no known bugs, and that can be applied to a previous major release will be cherry-picked to the relevant stable branch for future release. Changes will be grouped into a new minor version, unless an immediate fix is preferred in which case a bugfix version will be created instead. When a version is released, the API repository will have a tag created pointing to that release’s commit.

Feature Branches

New features or changes should be created in a feature/foo or fix/bar branch. This should be based on the most recent commit to bleeding. The only exception to this is if the changes are incompatible with the breaking changes in bleeding, in which case you should base against the relevant stable-x. You should state in your pull request why your change cannot be included in bleeding - such as fixing a bug in a feature that was removed by Mojang in a later release.

If the changes made are not breaking for a previous release, the Sponge team may also cherry-pick the changes to one or more stable branches assuming that no problems arise after the change is merged into bleeding.

SpongeDocs

The SpongeDocs themselves are unversioned following our philosophy that they will never be finished, but instead in a constant flux of ever increasing usability. However they target a specific version of the API, generally the most recent release of SpongeAPI.

Core Branch

The core branch for the SpongeDocs is stable. Each new commit to stable triggers a rebuild of the docs website. Commits to stable are generally made to document the most current SpongeAPI release or to fix minor mistakes on the Docs.

Feature Branches

Whenever a new feature is described, older texts are updated or reworded or the documents are restructured, it is done in a feature/foo or fix/bar branch. Those branches will then be reviewed and, once they are deemed complete, may be merged.

A feature branch may only be merged into master if the changes / additions made in it are correct regarding the SpongeAPI release currently targeted by the SpongeDocs. Any feature branches that describe features not yet included in a release stay unmerged until the corresponding API version is released and becomes the new targeted version for the SpongeDocs. However the Docs team might collect additions for a specific version on a single branch.

Release Branches

SpongeDocs uses release/x.y.z branches to publish Docs for older API versions like API 3.1.0. Older API releases are available on their respective branches. Whenever a new API version is released, the Docs Staff will create a new release/x.y.z branch and bump master to the new API version afterwards. A commit to a release branch also triggers a rebuild of the older Docs release, just like on the core branch.