srb-lens

A static analysis toolkit for Sorbet-typed Ruby projects. srb-lens parses Sorbet's internal outputs (CFG, symbol tables, autogen) and builds a queryable model of your project's methods, classes, types, and control flow.

For every method in your project, srb-lens gives you:

• Signature — arguments with types, return type, optional parameters
• Call graph — what methods are called, on what receiver types, with what return types
• Control flow — basic blocks, branch conditions, which calls happen under which branches
• Class hierarchy — superclasses, mixins, modules
• Instance variables — names and types
• Source locations — file paths and line numbers
• Block usage & rescue clauses

srb-lens/
  crates/
    srb-lens/          # Core Rust library
    srb-lens-cli/      # Command-line interface
  gems/
    srb_lens/          # Ruby gem (native extension via Magnus)

• Rust toolchain (stable, edition 2024)
• A Ruby project with Sorbet configured

cargo install --path crates/srb-lens-cli

cd /path/to/your-ruby-project
srb-lens index

This runs Sorbet with --print flags, parses the output, and caches everything in a .srb-lens/ directory. If your project uses Bundler:

srb-lens index --srb-command "bundle exec srb"

# Instance method
srb-lens query "User#activate!"

# Class method
srb-lens query "User.find_by_email"

# All methods in a class
srb-lens query "User"

# List matching method names only
srb-lens query "User" --list

# JSON output
srb-lens query "User#activate!" --json

You can pipe Sorbet's cfg-text output directly:

srb tc --print=cfg-text 2>/dev/null | srb-lens pipe "User#activate!"

Run Sorbet and build the index cache.

Query method or class information from the index.

Read cfg-text from stdin and query.

Partial class names are supported — Campaign matches Marketing::Campaign. Inherited methods are resolved by walking the superclass chain.

== Campaign#active? ==
  class: Campaign < ApplicationRecord
  mixins: Multitenancy, Archivable
  defined: app/models/campaign.rb:3
  source: app/models/campaign.rb:42
  args:
    at: Time (optional)
  returns: T.any(FalseClass, TrueClass)
  calls:
    Campaign.starts_at() -> T.nilable(Time)
    Campaign.ends_at() -> T.nilable(Time)
    Time.now() -> Time  when: <self>.starts_at() = true
  cfg:
    bb0 -> bb1
    bb1 -[<self>.starts_at()]-> true:bb2 / false:bb3
    bb2 -> return
    bb3 -> return

The srb_lens Ruby gem provides in-process access to the same analysis engine via a native extension (no subprocess, no JSON serialization overhead).

require "srb_lens"

project = SrbLens::Project.load_or_index("/path/to/project", srb_command: "bundle exec srb")

project.find_methods("Campaign#active?").each do |m|
  puts "#{m.fqn} -> #{m.return_type}"
  m.calls.each { |c| puts "  calls #{c.receiver_type}.#{c.method_name}" }
end

project.find_classes("Campaign").each do |c|
  puts "#{c.fqn} < #{c.super_class}  mixins: #{c.mixins.join(', ')}"
end

See gems/srb_lens/README.md for the full Ruby API reference.

cd gems/srb_lens
bundle install
bundle exec rake compile

srb-lens runs Sorbet with four --print flags and combines the results:

All outputs are cached in .srb-lens/ for fast subsequent loads.

MIT