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Contributing

Contributions are welcome. go-ruby-erb/erb is built to a small set of non-negotiable rules — they are what keep the compiler pure-Go, correct, and MRI-compatible. Please read these before opening a pull request.

Hard rules

  • Build from source — no vendoring. Everything compiles from source. Do not reach for prebuilt binaries or vendored blobs as a shortcut; being able to compile from source is a guarantee of independence.
  • 100% test coverage target, enforced in CI. New code ships with tests, and coverage is a CI gate. Fill the error branches, not just the happy path.
  • All GitHub content in English. Issues, pull requests, commits, comments, and discussions are English-only.
  • Differential testing against MRI. Correctness is defined by reference Ruby. A corpus of templates is compiled through both ruby and this library, and the emitted Ruby source and the rendered output are compared byte-for-byte — not approximated from memory. The reference is MRI 4.0.5.
  • Pure Go, cgo disabled. The whole point is a single static binary with no C toolchain. Code must build with CGO_ENABLED=0. If a feature seems to need C, it needs a pure-Go path instead.
  • The library compiles; it does not evaluate. Adding template rendering (the eval) to this module is out of scope — that needs an interpreter and belongs in the consumer. See Why a compiler, not a renderer.

Workflow

  1. Pick or open an issue describing the change.
  2. Work test-first: add the differential / unit tests, then make them pass.

  3. Run the full suite with coverage and confirm the gate is green:

    COVERPKG=$(go list ./... | paste -sd, -)
go test -race -coverpkg="$COVERPKG" -coverprofile=cover.out ./...
go tool cover -func=cover.out | tail -1   # 100.0%

  4. Open a PR in English, referencing the issue.

Where things live

The compiler — tag scanner, trim modes, the Compile / Compiler API, and ERB::Util — is in github.com/go-ruby-erb/erb. This documentation site is in github.com/go-ruby-erb/docs. Start from the Usage & API page and the Roadmap to find the right place for your change.