RBS setup

.github/workflows/tests.yml

@@ -18,17 +18,17 @@ jobs:
       uses: ruby/setup-ruby@e34163cd15f4bb403dcd72d98e295997e6a55798 # v1.238.0
       with:
         ruby-version: ${{ matrix.ruby }}
-    - uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        bundler-cache: true
+    - name: Cache RBS collection
+      uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
       with:
-        path: vendor/bundle
-        key: ${{ runner.os }}-gems-${{ hashFiles('**/Gemfile.lock') }}
+        path: .gem_rbs_collection
+        key: ${{ runner.os }}-rbs-${{ hashFiles('rbs_collection.lock.yaml') }}
         restore-keys: |
-          ${{ runner.os }}-gems-
-    - name: Install dependencies
-      run: |
-        gem install bundler
-        bundle config path vendor/bundle
-        bundle install --jobs 4 --retry 3
+          ${{ runner.os }}-rbs-
     - name: Run tests
       run: |
-        bundle exec rake
+        bundle exec rake spec
+    - name: Run typecheck
+      run: |
+        bundle exec rake typecheck

.gitignore

@@ -49,3 +49,6 @@ pkg
 
 .rspec_status
 .DS_Store
+
+# RBS collection (installed via rbs collection install)
+.gem_rbs_collection

Gemfile

@@ -8,3 +8,5 @@ gem "rubocop-shopify", ">=2.8.0", require: false
 gem "rubocop-performance", require: false
 
 gemspec
+
+gem "steep", "~> 1.10"

Gemfile.lock

@@ -88,6 +88,7 @@ GEM
     concurrent-ruby (1.3.5)
     connection_pool (2.5.0)
     crass (1.0.6)
+    csv (3.3.5)
     database_cleaner (2.0.2)
       database_cleaner-active_record (>= 2, < 3)
     database_cleaner-active_record (2.2.0)
@@ -99,6 +100,13 @@ GEM
     docile (1.4.1)
     drb (2.2.1)
     erubi (1.13.1)
+    ffi (1.17.3-aarch64-linux-gnu)
+    ffi (1.17.3-arm-linux-gnu)
+    ffi (1.17.3-arm64-darwin)
+    ffi (1.17.3-x86-linux-gnu)
+    ffi (1.17.3-x86_64-darwin)
+    ffi (1.17.3-x86_64-linux-gnu)
+    fileutils (1.7.3)
     globalid (1.2.1)
       activesupport (>= 6.1)
     i18n (1.14.7)
@@ -111,6 +119,9 @@ GEM
     json (2.13.2)
     language_server-protocol (3.17.0.5)
     lint_roller (1.1.0)
+    listen (3.9.0)
+      rb-fsevent (~> 0.10, >= 0.10.3)
+      rb-inotify (~> 0.9, >= 0.9.10)
     logger (1.7.0)
     loofah (2.24.0)
       crass (~> 1.0.2)
@@ -125,6 +136,7 @@ GEM
     mini_mime (1.1.5)
     mini_portile2 (2.8.8)
     minitest (5.25.5)
+    mutex_m (0.3.0)
     net-imap (0.5.7)
       date
       net-protocol
@@ -206,6 +218,11 @@ GEM
       zeitwerk (~> 2.6)
     rainbow (3.1.1)
     rake (13.2.1)
+    rb-fsevent (0.11.2)
+    rb-inotify (0.11.1)
+      ffi (~> 1.0)
+    rbs (3.9.5)
+      logger
     rdoc (6.13.1)
       psych (>= 4.0.0)
     regexp_parser (2.11.0)
@@ -258,14 +275,35 @@ GEM
     sqlite3 (2.6.0-x86-linux-gnu)
     sqlite3 (2.6.0-x86_64-darwin)
     sqlite3 (2.6.0-x86_64-linux-gnu)
+    steep (1.10.0)
+      activesupport (>= 5.1)
+      concurrent-ruby (>= 1.1.10)
+      csv (>= 3.0.9)
+      fileutils (>= 1.1.0)
+      json (>= 2.1.0)
+      language_server-protocol (>= 3.17.0.4, < 4.0)
+      listen (~> 3.0)
+      logger (>= 1.3.0)
+      mutex_m (>= 0.3.0)
+      parser (>= 3.1)
+      rainbow (>= 2.2.2, < 4.0)
+      rbs (~> 3.9)
+      securerandom (>= 0.1)
+      strscan (>= 1.0.0)
+      terminal-table (>= 2, < 5)
+      uri (>= 0.12.0)
     stringio (3.1.6)
+    strscan (3.1.5)
+    terminal-table (4.0.0)
+      unicode-display_width (>= 1.1.1, < 4)
     thor (1.3.2)
     timeout (0.4.3)
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
     unicode-display_width (3.1.4)
       unicode-emoji (~> 4.0, >= 4.0.4)
     unicode-emoji (4.0.4)
+    uri (1.0.4)
     useragent (0.16.11)
     websocket-driver (0.7.7)
       base64
@@ -287,13 +325,15 @@ DEPENDENCIES
   ostruct
   pry-byebug
   rails (~> 7.2)
+  rbs (~> 3.0)
   rspec (~> 3.2)
   rubocop
   rubocop-performance
   rubocop-shopify (>= 2.8.0)
   shopify-money!
   simplecov
   sqlite3
+  steep (~> 1.10)
 
 BUNDLED WITH
    2.6.7

Rakefile

@@ -30,7 +30,34 @@ RSpec::Core::RakeTask.new(:rcov) do |spec|
   spec.rcov = true
 end
 
-task default: :spec
+namespace :rbs do
+  desc "Install RBS collection"
+  task :install do
+    sh "rbs collection install > /dev/null"
+  end
+
+  desc "Validate RBS type signatures"
+  task validate: :install do
+    sh "rbs -I sig validate"
+  end
+
+  desc "List RBS files"
+  task :list do
+    sh "find sig -name '*.rbs'"
+  end
+end
+
+namespace :steep do
+  desc "Type check Ruby code against RBS signatures"
+  task check: "rbs:install" do
+    sh "steep check --jobs 2"
+  end
+end
+
+desc "Run all type checks (RBS validation + Steep type checking)"
+task typecheck: ["rbs:validate", "steep:check"]
+
+task default: [:spec, :typecheck]
 
 require 'rake/task'
 RDoc::Task.new do |rdoc|

Steepfile

@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+target :lib do
+  signature "sig"
+
+  check "lib"
+  ignore "lib/rubocop/**/*.rb" # RuboCop cops use metaprogramming DSL
+  ignore "lib/money/railtie.rb" # Rails types
+  ignore "lib/money/deprecations.rb" # Uses class_eval
+  ignore "lib/money/rails/**/*.rb" # Rails-specific code
+  ignore "lib/money_column/railtie.rb" # Rails types
+  ignore "lib/money_column/active_record_hooks.rb" # Heavy metaprogramming with define_method
+
+  library "bigdecimal"
+  library "json"
+  library "forwardable"
+  library "yaml"
+
+  configure_code_diagnostics(Steep::Diagnostic::Ruby.lenient)
+end

dev.yml

@@ -12,4 +12,4 @@ up:
 - ruby
 - bundler
 commands:
-  test: bundle exec rspec
+  test: bundle exec rake

lib/money/currency/loader.rb

@@ -5,7 +5,7 @@
 class Money
   class Currency
     module Loader
-      CURRENCY_DATA_PATH = File.expand_path("../../../config", __dir__)
+      CURRENCY_DATA_PATH = File.expand_path("../../../config", __dir__ || raise("__dir__ is nil"))
 
       class << self
         def load_currencies

money.gemspec

@@ -15,13 +15,15 @@ Gem::Specification.new do |s|
   s.summary = "Shopify's money gem"
 
   s.metadata['allowed_push_host'] = "https://rubygems.org"
+  s.metadata['rbs_types'] = "sig"
 
   s.add_dependency("bigdecimal", ">= 3.0")
 
   s.add_development_dependency("bundler")
   s.add_development_dependency("database_cleaner", "~> 2.0")
   s.add_development_dependency("ostruct")
   s.add_development_dependency("rails", "~> 7.2")
+  s.add_development_dependency("rbs", "~> 3.0")
   s.add_development_dependency("rspec", "~> 3.2")
   s.add_development_dependency("simplecov", ">= 0")
   s.add_development_dependency("sqlite3")