Roadmap

go-ruby-rubocop/rubocop is grown test-first, each capability differential-tested against the rubocop gem rather than built in isolation. The deterministic, interpreter-independent slice of RuboCop — offense detection over a Ruby source string — is complete for its core cop set.

Stage	What	Status
Cop framework & Offense model	A Cop interface (Inspect(*Source, CopConfig) []Offense), an Offense{CopName, Location, Message, Severity, Correctable, Correction} model, a Registry and a Runner (the commissioner) that runs every enabled cop over a lexed+parsed Source and returns offenses in RuboCop's report order.	Done
Core cop set (22 cops)	A faithful core set of 22 cops across Layout / Style / Lint / Metrics — detection, location and message text validated differentially against the gem.	Done
Configuration (.rubocop.yml)	ParseConfig reads a .rubocop.yml (via go-ruby-yaml) into a Config: AllCops.DisabledByDefault, per-cop Enabled, and per-cop params (Max, EnforcedStyle, …); a cop's effective config is its built-in default merged with the file's overrides.	Done
Formatters	SimpleTextFormatter (--format simple) and ProgressFormatter (--format progress), including the byte-faithful summary line (N files inspected, M offenses detected[, K offenses autocorrectable]).	Done
go-ruby-parser AST integration	Built on the go-ruby-parser Ruby AST and lexer; each cop inspects a Ruby source string through its lines, its token stream and its AST — no Ruby runtime — and computes a source-range Correction the host applies.	Done
Differential oracle & coverage	A corpus of Ruby snippets inspected both here and by the rubocop gem, cop name + line/col + message plus formatter output compared byte-for-byte; 100% coverage, gofmt + go vet clean, green across all six 64-bit Go arches and three OSes.	Done

Documented out-of-scope boundaries

These are deliberate, recorded so the module's surface is unambiguous:

• A core cop set, not the whole gem. RuboCop bundles ~500 cops; the ~480 beyond the core set above are deliberately absent rather than stubbed. Parameterised cops honour the subset of gem params they document (Max, Width, MinDigits, EnforcedStyle, MinBodyLength); some non-always styles are recognised (they switch the cop off) but not yet re-implemented.
• Detection here, application by the host. Each cop computes the edit (a source-range Correction); rewriting the file is the consumer's job — that is why rbgo binds this module rather than the reverse.
• No file-walking. The library inspects a source string, not a directory tree. Locating files is the host's concern.
• Reference is the rubocop gem. Byte-for-byte conformance targets the gem's behaviour, matched to the version used by the differential oracle.
• Standalone & reusable. The module has no dependency on the Ruby runtime; the dependency runs the other way.

See Usage & API for the surface and Why pure Go for the deterministic/interpreter split.