changelog¶

Turn commit history into a changelog — and read one back into a typed model. changelog walks a repository's Conventional Commits to generate a categorised changelog, and parses an existing release-notes document into Changelog → Release → Entry you can query.

go get gitlab.com/phpboyscout/go/changelog

// Generate from the repo's tags and commits.
md, err := changelog.GenerateFromRepo(".", changelog.WithSinceTag("v1.2.0"))

// Parse existing notes and inspect them.
cl, err := changelog.Parse(rawNotes) // ErrNoReleases when nothing parseable
if cl.HasBreakingChanges() {
    // ...
}

It is a library, not a command: there is no binary, no configuration file and no environment variable. Everything that varies is an argument.

Start here¶

Generate your first changelog — fifteen minutes, from an empty directory to a CHANGELOG.md and a build that fails on a breaking change.

Two halves¶

Generate from git history — GenerateFromRepo opens the repo with go-git, reads tags and commits, classifies each Conventional Commit, and renders newest-first markdown. Bound it with WithSinceTag or WithMaxReleases; keep non-conforming commit messages with WithIncludeAll.
Parse existing release notes — Parse and ParseFromArchive turn a markdown changelog (or a gzip/tar release archive) back into a typed Changelog, with HasBreakingChanges, BreakingChanges, and EntriesByCategory to query it and FormatSummary to render a short summary.

How commits become entries¶

Each commit subject is classified into a Category — breaking, feature, fix, performance, or other — with its scope and description pulled out, and attributed to the earliest release whose tag can reach it. Releases are ordered by semver, newest first.

Commit classification — which types map where, and which are dropped.
How commits are attributed to releases — why ancestry rather than dates, and what happens to merge commits and re-tags.

Look something up¶

The reference section covers every option and its default, the exact markdown emitted, the exact markdown accepted, and every error value. Go signatures live on pkg.go.dev.

Before designing around it, read what changelog does not do — no CLI, no templating, no commit links, no path or scope filtering, and nothing read from the commit body but the breaking-change footer.

No framework weight¶

The whole dependency graph is go-git, the leodido conventional-commits parser, x/mod, and cockroachdb/errors — enforced by a depfootprint test.