Add type checking commands (#56)

- Install rbs and steep
- Initialize type checkers

  bundle exec steep init
  bundle exec rbs collection init
  bundle exec rbs collection install

- Configure Steep to check app and lib
- Add typecheck commands to Makefile

## Context

Now that we moved off of the template structure we're unblocked to add
type checking

Author: lorenyu

.gitignore

@@ -20,3 +20,6 @@ spec/dummy/db/*.sqlite[0-9]*
 
 # simplecov coverage report
 coverage/*
+
+# typechecking
+.gem_rbs_collection

Gemfile

@@ -27,6 +27,10 @@ group :development do
   gem "rubocop-rails-omakase", require: false
   gem "rubocop-rspec", require: false
 
+  # Type checking
+  gem "rbs"
+  gem "steep", require: false
+
   # Hot reloading for Lookbook
   gem "listen"
   gem "actioncable"

Gemfile.lock

@@ -91,6 +91,7 @@ GEM
     crass (1.0.6)
     css_parser (1.21.1)
       addressable
+    csv (3.3.4)
     date (3.4.1)
     diff-lcs (1.6.0)
     docile (1.4.1)
@@ -104,6 +105,7 @@ GEM
     ffi (1.17.1-x86_64-darwin)
     ffi (1.17.1-x86_64-linux-gnu)
     ffi (1.17.1-x86_64-linux-musl)
+    fileutils (1.7.3)
     formatador (1.1.0)
     globalid (1.2.1)
       activesupport (>= 6.1)
@@ -164,6 +166,7 @@ GEM
     method_source (1.1.0)
     mini_mime (1.1.5)
     minitest (5.25.5)
+    mutex_m (0.3.0)
     nenv (0.3.0)
     net-imap (0.5.6)
       date
@@ -254,6 +257,8 @@ GEM
     rb-fsevent (0.11.2)
     rb-inotify (0.11.1)
       ffi (~> 1.0)
+    rbs (3.9.3)
+      logger
     rdoc (6.12.0)
       psych (>= 4.0.0)
     redcarpet (3.6.1)
@@ -338,7 +343,27 @@ GEM
     sqlite3 (2.6.0-x86_64-darwin)
     sqlite3 (2.6.0-x86_64-linux-gnu)
     sqlite3 (2.6.0-x86_64-linux-musl)
+    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 (3.1.5)
+    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)
@@ -376,13 +401,15 @@ DEPENDENCIES
   listen
   lookbook (>= 2.3.9)
   puma
+  rbs
   rspec-rails (~> 7.0.0)
   rubocop-rails-omakase
   rubocop-rspec
   shoulda-matchers (~> 6.0)
   simplecov
   sprockets-rails
   sqlite3
+  steep
 
 BUNDLED WITH
    2.5.22

Makefile

@@ -3,7 +3,9 @@
 	lint-ci \
 	test \
 	test-coverage \
-	test-watch
+	test-watch \
+	typecheck \
+	help
 
 setup:
 	bundle install
@@ -23,5 +25,8 @@ test-watch: ## Watch for file changes and run the test suite
 test-coverage: ## Open the test coverage report
 	open coverage/index.html
 
+typecheck: ## Run type checking
+	bundle exec steep check	
+
 help: ## Prints the help documentation and info about each command
 	@grep -Eh '^[/a-zA-Z0-9_-]+:.*?## .*$$' $(MAKEFILE_LIST) | sort | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-30s\033[0m %s\n", $$1, $$2}'

Steepfile

@@ -0,0 +1,33 @@
+# D = Steep::Diagnostic
+#
+target :lib do
+  signature "sig"
+  ignore_signature "sig/test"
+
+  check "app"
+  check "lib"
+  # check "path/to/source.rb"         # File name
+  # check "app/models/**/*.rb"        # Glob
+  # ignore "lib/templates/*.rb"
+
+  # library "pathname"              # Standard libraries
+  # library "strong_json"           # Gems
+
+  # configure_code_diagnostics(D::Ruby.default)      # `default` diagnostics setting (applies by default)
+  # configure_code_diagnostics(D::Ruby.strict)       # `strict` diagnostics setting
+  # configure_code_diagnostics(D::Ruby.lenient)      # `lenient` diagnostics setting
+  # configure_code_diagnostics(D::Ruby.silent)       # `silent` diagnostics setting
+  # configure_code_diagnostics do |hash|             # You can setup everything yourself
+  #   hash[D::Ruby::NoMethod] = :information
+  # end
+end
+
+# target :test do
+#   unreferenced!                     # Skip type checking the `lib` code when types in `test` target is changed
+#   signature "sig/test"              # Put RBS files for tests under `sig/test`
+#   check "test"                      # Type check Ruby scripts under `test`
+#
+#   configure_code_diagnostics(D::Ruby.lenient)      # Weak type checking for test code
+#
+#   # library "pathname"              # Standard libraries
+# end