rigor-rbs-inline

Ingests rbs-inline-shaped comments (# @rbs name: T, #: () -> T, # @rbs return: T, attribute #: casts, # @rbs! raw RBS, …) in your Ruby source and feeds the synthesised RBS into the analysis environment — so a # @rbs annotation Rigor would otherwise ignore becomes an enforced contract that fires the same argument-type-mismatch diagnostics as a hand-written .rbs file. The design is recorded in ADR-32.

It ships bundled in rigortype. Activate it under plugins::

plugins:
  - rigor-rbs-inline

Full guide. The worked walkthrough — every supported annotation form, the magic-comment opt-in, the top-level-def caveat, and parse- failure handling — is handbook chapter 7 — RBS and Extended, § “Inline RBS in Ruby source”. This page is the operational quick reference.

What it does

Per file, opt in with the upstream magic comment:

# rbs_inline: enabled

class AscDesc
  # @rbs asc_or_desc: :asc | :desc
  def ascdesc(asc_or_desc) = asc_or_desc
end

AscDesc.new.ascdesc(:bad)   # error: argument type mismatch — expected :asc | :desc, got :bad

Files without # rbs_inline: enabled are untouched (a top-of-file scan only). The synthesised RBS is cached per file (keyed on content SHA + plugin id/version + config), so an unchanged second run skips the parse.

Rule	Severity	Fires when
plugin.rbs-inline.source-rbs-synthesis-failed	info	rbs-inline could not parse a file; analysis falls back to no inline-RBS contribution and the diagnostic carries the upstream error

Configuration

plugins:
  - gem: rigor-rbs-inline
    config:
      require_magic_comment: true   # default

• require_magic_comment (default true) — when true, only files carrying # rbs_inline: enabled are processed. Set false to treat every file as if it carried the magic comment — useful only when you own the whole analysis scope (a single-file CI run or the hosted browser playground, which sets it so pasted snippets analyse without the magic line).

Limitations

• Top-level def produces no RBS. Upstream rbs-inline emits nothing for a bare top-level def (verified against rbs-inline 0.14.0) — wrap the method in a class / module. This is an inherited upstream behaviour, not a Rigor limitation.
• Parse failures fail soft. A file rbs-inline can’t parse is analysed as if it had no inline RBS (the :info diagnostic above records it); re-stamp the severity via severity_profile: to escalate.
• Runtime dependency. The plugin pulls in the rbs-inline gem; core rigortype stays zero-runtime-dep, so only projects that opt in pay it.

Plugin internals

The synthesizer, the source_rbs_synthesizer: manifest hook, and the caching wiring are in the plugin’s README. To write a plugin, see examples/ and the rigor-plugin-author skill.