diff --git a/CHANGELOG.md b/CHANGELOG.md
index 19814976..c1db20ab 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,8 @@
 ## HEAD
 
 * Fix ruby 2.7 deprecation warnings [#241](https://github.com/Sorcery/sorcery/pull/241)
+* Fix Thor-related warning in generator [#252](https://github.com/Sorcery/sorcery/pull/252)
+* Check submodule availability in generator [#252](https://github.com/Sorcery/sorcery/pull/252)
 
 ## 0.15.0
 
diff --git a/Gemfile b/Gemfile
index 532fc3ce..fa75df15 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,8 +1,3 @@
 source 'https://rubygems.org'
 
-gem 'pry'
-gem 'rails'
-gem 'rails-controller-testing'
-gem 'sqlite3'
-
 gemspec
diff --git a/Rakefile b/Rakefile
index 2470119d..6877f832 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,6 +1,21 @@
 require 'bundler/gem_tasks'
-
 require 'rspec/core/rake_task'
+
 RSpec::Core::RakeTask.new(:spec)
 
 task default: :spec
+
+task :console do
+  require 'byebug'
+  require 'pry'
+  require 'rails'
+  require 'sorcery'
+
+  def reload!
+    files = $LOADED_FEATURES.select { |feat| feat =~ /\/sorcery\// }
+    files.each { |file| load file }
+  end
+
+  ARGV.clear
+  Pry.start
+end
diff --git a/lib/generators/sorcery/helpers.rb b/lib/generators/sorcery/helpers.rb
index 5bc94408..5ef1c03f 100644
--- a/lib/generators/sorcery/helpers.rb
+++ b/lib/generators/sorcery/helpers.rb
@@ -3,8 +3,28 @@ module Generators
     module Helpers
       private
 
-      def sorcery_config_path
-        'config/initializers/sorcery.rb'
+      def initializer_path
+        File.join(initializers_path, 'sorcery.rb')
+      end
+
+      def initializers_path
+        File.join('config', 'initializers')
+      end
+
+      def migration_class_name
+        if Rails::VERSION::MAJOR >= 5
+          "ActiveRecord::Migration[#{Rails::VERSION::MAJOR}.#{Rails::VERSION::MINOR}]"
+        else
+          'ActiveRecord::Migration'
+        end
+      end
+
+      def migration_path(submodule)
+        File.join(migrations_path, "sorcery_#{submodule}.rb")
+      end
+
+      def migrations_path
+        File.join('db', 'migrate')
       end
 
       # Either return the model passed in a classified form or return the default "User".
@@ -12,32 +32,51 @@ def model_class_name
         options[:model] ? options[:model].classify : 'User'
       end
 
-      def tableized_model_class
-        options[:model] ? options[:model].gsub(/::/, '').tableize : 'User'
+      def model_injection
+        indents = model_class_name.split('::').count
+        indents += 1 if namespace
+
+        "#{'  ' * indents}authenticates_with_sorcery!\n"
+      end
+
+      def model_injection_point
+        "class #{model_class_name} < #{model_superclass_name}\n"
+      end
+
+      def model_name
+        if namespace
+          [namespace.to_s] + [model_class_name]
+        else
+          [model_class_name]
+        end.join('::')
       end
 
       def model_path
-        @model_path ||= File.join('app', 'models', "#{file_path}.rb")
+        File.join(models_path, "#{model_name.underscore}.rb")
+      end
+
+      def models_path
+        File.join('app', 'models')
       end
 
-      def file_path
-        model_name.underscore
+      def model_superclass_name
+        if Rails::VERSION::MAJOR >= 5
+          'ApplicationRecord'
+        else
+          'ActiveRecord::Base'
+        end
       end
 
       def namespace
         Rails::Generators.namespace if Rails::Generators.respond_to?(:namespace)
       end
 
-      def namespaced?
-        !!namespace
+      def only_submodules?
+        options[:migrations] || options[:only_submodules]
       end
 
-      def model_name
-        if namespaced?
-          [namespace.to_s] + [model_class_name]
-        else
-          [model_class_name]
-        end.join('::')
+      def tableized_model_class
+        model_class_name.gsub(/::/, '').tableize
       end
     end
   end
diff --git a/lib/generators/sorcery/install_generator.rb b/lib/generators/sorcery/install_generator.rb
index c3fefa32..00186096 100644
--- a/lib/generators/sorcery/install_generator.rb
+++ b/lib/generators/sorcery/install_generator.rb
@@ -7,6 +7,16 @@ class InstallGenerator < Rails::Generators::Base
       include Rails::Generators::Migration
       include Sorcery::Generators::Helpers
 
+      AVAILABLE_SUBMODULES = %w[
+        activity_logging
+        brute_force_protection
+        external
+        magic_login
+        remember_me
+        reset_password
+        user_activation
+      ].freeze
+
       source_root File.expand_path('templates', __dir__)
 
       argument :submodules, optional: true, type: :array, banner: 'submodules'
@@ -26,49 +36,52 @@ def check_deprecated_options
         warn('[DEPRECATED] `--migrations` option is deprecated, please use `--only-submodules` instead')
       end
 
-      # Copy the initializer file to config/initializers folder.
-      def copy_initializer_file
-        template 'initializer.rb', sorcery_config_path unless only_submodules?
+      def check_available_submodules
+        return unless submodules
+
+        guidance = "Try some of these: #{AVAILABLE_SUBMODULES.join(', ')}"
+
+        submodules.each do |submodule|
+          raise ArgumentError, "#{submodule} is not a Sorcery submodule. #{guidance}" unless
+            AVAILABLE_SUBMODULES.include?(submodule)
+        end
       end
 
-      def configure_initializer_file
-        # Add submodules to the initializer file.
+      # Copy the initializer file to config/initializers folder, and add the submodules if necessary.
+      def install_initializer
+        template 'initializer.rb', initializer_path unless only_submodules?
+
         return unless submodules
 
         submodule_names = submodules.collect { |submodule| ':' + submodule }
 
-        gsub_file sorcery_config_path, /submodules = \[.*\]/ do |str|
+        gsub_file initializer_path, /submodules = \[.*\]/ do |str|
           current_submodule_names = (str =~ /\[(.*)\]/ ? Regexp.last_match(1) : '').delete(' ').split(',')
           "submodules = [#{(current_submodule_names | submodule_names).join(', ')}]"
         end
       end
 
-      def configure_model
+      def install_model
         # Generate the model and add 'authenticates_with_sorcery!' unless you passed --only-submodules
         return if only_submodules?
 
         generate "model #{model_class_name} --skip-migration"
-        inject_sorcery_to_model
-      end
-
-      def inject_sorcery_to_model
-        indents = '  ' * (namespaced? ? 2 : 1)
-
-        inject_into_class(model_path, model_class_name, "#{indents}authenticates_with_sorcery!\n")
+        
+        inject_into_class(model_path, model_class_name, model_injection, after: model_injection_point)
       end
 
       # Copy the migrations files to db/migrate folder
-      def copy_migration_files
+      def install_migrations
         # Copy core migration file in all cases except when you pass --only-submodules.
         return unless defined?(ActiveRecord)
 
-        migration_template 'migration/core.rb', 'db/migrate/sorcery_core.rb', migration_class_name: migration_class_name unless only_submodules?
+        migration_template 'migration/core.rb', migration_path(:core), migration_class_name: migration_class_name unless only_submodules?
 
         return unless submodules
 
         submodules.each do |submodule|
           unless %w[http_basic_auth session_timeout core].include?(submodule)
-            migration_template "migration/#{submodule}.rb", "db/migrate/sorcery_#{submodule}.rb", migration_class_name: migration_class_name
+            migration_template "migration/#{submodule}.rb", migration_path(submodule), migration_class_name: migration_class_name
           end
         end
       end
@@ -82,20 +95,6 @@ def self.next_migration_number(dirname)
           format('%.3d', (current_migration_number(dirname) + 1))
         end
       end
-
-      private
-
-      def only_submodules?
-        options[:migrations] || options[:only_submodules]
-      end
-
-      def migration_class_name
-        if Rails::VERSION::MAJOR >= 5
-          "ActiveRecord::Migration[#{Rails::VERSION::MAJOR}.#{Rails::VERSION::MINOR}]"
-        else
-          'ActiveRecord::Migration'
-        end
-      end
     end
   end
 end
diff --git a/sorcery.gemspec b/sorcery.gemspec
index 7a90e92b..7b492b1a 100644
--- a/sorcery.gemspec
+++ b/sorcery.gemspec
@@ -38,9 +38,13 @@ Gem::Specification.new do |s|
   s.add_dependency 'oauth2', '~> 1.0', '>= 0.8.0'
 
   s.add_development_dependency 'byebug', '~> 10.0.0'
+  s.add_development_dependency 'pry'
+  s.add_development_dependency 'rails'
+  s.add_development_dependency 'rails-controller-testing'
   s.add_development_dependency 'rspec-rails', '~> 3.7.0'
   s.add_development_dependency 'rubocop'
   s.add_development_dependency 'simplecov', '>= 0.3.8'
+  s.add_development_dependency 'sqlite3'
   s.add_development_dependency 'test-unit', '~> 3.2.0'
   s.add_development_dependency 'timecop'
   s.add_development_dependency 'webmock', '~> 3.3.0'
diff --git a/spec/generators/install_generator_spec.rb b/spec/generators/install_generator_spec.rb
new file mode 100644
index 00000000..eb0730be
--- /dev/null
+++ b/spec/generators/install_generator_spec.rb
@@ -0,0 +1,133 @@
+require 'spec_helper'
+require 'support/generator_helper'
+
+require 'generators/sorcery/install_generator'
+
+describe 'install generator' do
+  include GeneratorHelper
+
+  class TestInstallGenerator < Sorcery::Generators::InstallGenerator
+    source_root File.expand_path('../../lib/generators/sorcery/templates', __dir__)
+
+    def self.next_migration_number(dirname)
+      current_migration_number(dirname) + 1
+    end
+  end
+
+  tests TestInstallGenerator
+
+  context 'given deprecated --migrations option' do
+    let(:installer) do
+      generator(options: { migrations: true })
+    end
+
+    it 'shows warning' do
+      expect(installer).to receive(:warn).with(/\[DEPRECATED\] `--migrations` option is deprecated/)
+      installer.check_deprecated_options
+    end
+  end
+
+  context 'given invalid submodule' do
+    it 'raises error' do
+      expect {
+        generator('invalid_submodule').check_available_submodules
+      }.to raise_error(ArgumentError).with_message(/invalid_submodule is not a Sorcery submodule/)
+    end
+  end
+
+  describe 'initializer' do
+    describe 'installation' do
+      let(:installation) { invoke!(:install_initializer) }
+
+      it 'creates initializer' do
+        expect(installation).to match(/create  config\/initializers\/sorcery.rb/)
+      end
+    end
+
+    describe 'configuration' do
+      context 'given submodule(s)' do
+        let(:initializer_contents) do
+          File.read(initializer_path)
+        end
+  
+        before do
+          invoke!(:install_initializer, 'activity_logging')
+        end
+  
+        it 'adds submodule(s) to initializer' do
+          expect(initializer_contents).to match(/Rails\.application\.config\.sorcery\.submodules = \[:activity_logging\]/)
+        end
+      end
+    end
+
+    describe 'uninstallation' do
+      let(:uninstallation) { revoke!(:install_initializer) }
+
+      before do
+        invoke!(:install_initializer)
+      end
+
+      it 'removes initializer' do
+        expect(uninstallation).to match(/remove  config\/initializers\/sorcery.rb/)
+      end
+    end
+  end
+
+  describe 'model' do
+    describe 'installation' do
+      let(:installation) { invoke!(:install_model) }
+
+      it 'skips migration' do
+        expect(installation).to match(/generate  model User \-\-skip\-migration/)
+      end
+
+      it 'creates model' do
+        expect(installation).to match(/create    app\/models\/user\.rb/)
+      end
+    end
+
+    describe 'configuration' do
+      let(:model_contents) do
+        File.read(model_path(:user))
+      end
+
+      before do
+        invoke!(:install_model)
+      end
+
+      it 'adds `authenticates_with_sorcery!`' do
+        expect(model_contents).to match(/authenticates_with_sorcery!/)
+      end
+    end
+
+    describe 'uninstallation' do
+      let(:uninstallation) { revoke!(:install_model) }
+
+      before do
+        invoke!(:install_model)
+      end
+
+      it 'removes `authenticates_with_sorcery!`' do
+        expect(uninstallation).to match(/subtract  app\/models\/user.rb/)
+      end
+    end
+  end
+
+  describe 'migrations' do
+    describe 'installation' do
+      let(:installation) { invoke!(:install_migrations, 'activity_logging', options: { only_submodules: true }) }
+
+      it 'creates migration' do
+        expect(installation).to match(/create  db\/migrate\/1_sorcery_activity_logging.rb/)
+      end
+    end
+
+    describe 'uninstallation' do
+      let(:uninstallation) { revoke!(:install_migrations, 'activity_logging', options: { only_submodules: true }) }
+
+      it 'removes migration' do
+        expect(uninstallation).to match(/remove  db\/migrate\/1_sorcery_activity_logging.rb/)
+      end
+    end
+  end
+end
diff --git a/spec/rails_app/bin/rails b/spec/rails_app/bin/rails
new file mode 100644
index 00000000..cf808618
--- /dev/null
+++ b/spec/rails_app/bin/rails
@@ -0,0 +1,11 @@
+#!/usr/bin/env ruby
+
+# Really, this should come from spec_helper.rb somehow -- but for some reason, doesn't work
+# when running generators... this is why it's added here. Hopefully someone a little wiser
+# than I can fix this.
+#
+SORCERY_ORM = :active_record
+
+APP_PATH = File.expand_path('../config/application', __dir__)
+require_relative '../config/boot'
+require 'rails/commands'
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index bc5c48aa..cab42a12 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -9,6 +9,7 @@
 # SimpleCov.root File.join(File.dirname(__FILE__), '..', 'lib')
 # SimpleCov.start
 require 'rails/all'
+require 'rails-controller-testing'
 require 'rspec/rails'
 require 'timecop'
 require 'byebug'
diff --git a/spec/support/generator_helper.rb b/spec/support/generator_helper.rb
new file mode 100644
index 00000000..6172b410
--- /dev/null
+++ b/spec/support/generator_helper.rb
@@ -0,0 +1,91 @@
+require 'active_support/concern'
+require 'active_support/testing/stream'
+require 'rails/generators'
+
+module GeneratorHelper
+  extend ActiveSupport::Concern
+  include ActiveSupport::Testing::Stream
+  include FileUtils
+
+  included do |base|
+    class_attribute :destination_root, default: File.expand_path('../rails_app', __dir__)
+    class_attribute :generator_class
+
+    base.teardown :remove_installation!
+  end
+
+  module ClassMethods
+    def tests(klass)
+      self.generator_class = klass
+    end
+
+    def destination(path)
+      self.destination_root = path
+    end
+  end
+
+  # Instantiate the generator.
+  def generator(*args, options: {}, config: {})
+    generator_class.new(args, options, config.reverse_merge(destination_root: destination_root))
+  end
+
+  # Invoke a specific action
+  def invoke!(action, *args, options: {}, config: {})
+    gen = generator(*args, options: options, config: config.reverse_merge(behavior: :invoke))
+
+    capture(:stdout) do
+      gen.invoke(action)
+    end
+  end
+
+  # Revoke a specific action
+  def revoke!(action, *args, options: {}, config: {})
+    gen = generator(*args, options: options, config: config.reverse_merge(behavior: :revoke))
+
+    capture(:stdout) do
+      gen.invoke(action)
+    end
+  end
+
+  def initializer_path
+    @initializer_path ||= File.join(destination_root, 'config', 'initializers', 'sorcery.rb')
+  end
+
+  def migrations_path
+    @migrations_path ||= File.join(destination_root, 'db', 'migrate')
+  end
+
+  # def migration_path(migration)
+  #   @migration_path ||= {}
+  #   @migration_path[migration.to_s] ||= Dir.glob("#{migrations_path}/[0-9]*_*.rb")
+  #     .grep(/\d+_#{migration}.rb$/)
+  #     .first
+  # end
+
+  def model_path(model)
+    @model_path ||= {}
+    @model_path[model.to_s] ||= File.join(destination_root, 'app', 'models', "#{model}.rb")
+  end
+
+private
+
+  def remove_installation!
+    # Remove any generated initializers, models, migrations files
+    files = [initializer_path]
+    files += Dir.glob(File.join(destination_root, 'app', 'models', '*.rb'))
+    files += Dir.glob(File.join(destination_root, 'db', 'migrate', '*.rb'))
+
+    files.each do |file|
+      rm_f(file) if File.exists?(file)
+    end
+
+    # Recursively remove full directories
+    dirs = [
+      File.join(destination_root, 'test')
+    ]
+
+    dirs.each do |dir|
+      rm_rf(dir) if Dir.exists?(dir)
+    end
+  end
+end
\ No newline at end of file