Add importmap support in generator (#9)

* Add importmap support in generator

* Use #run helper to execute command

* Add tests for Importmap and none asset pipelines

* Use newer RSpec syntax to remove dep. warning

* Update generator description

* Pin psych to >= 5.1.1.1

* Sort gem dep

* Rerun CI

* Fix tests run twice

.github/workflows/ci.yml

@@ -43,4 +43,3 @@ jobs:
         ./cc-test-reporter after-build --exit-code 0
       env:
         CC_TEST_REPORTER_ID: 903dc1a761aaec438bc9f39467e2cb4a2ea332bdb65241b37abef6338c5e6326
-    - run: bundle exec rspec

htmx-rails.gemspec

@@ -24,6 +24,7 @@ Gem::Specification.new do |spec|
 
   # Development dependencies.
   spec.add_development_dependency 'generator_spec'
+  spec.add_development_dependency 'psych', '>= 5.1.1.1' # pinned due to https://github.com/ruby/psych/issues/655
   spec.add_development_dependency 'rake'
   spec.add_development_dependency 'reek'
   spec.add_development_dependency 'rspec'

lib/generators/htmx/install_generator.rb

@@ -5,15 +5,20 @@ module Generators
     class InstallGenerator < ::Rails::Generators::Base
       WEBPACKER_SETUP = "require('htmx.org')\n"
       SPROCKETS_SETUP = "//= require htmx\n"
+      IMPORTMAP_SETUP = "import \"htmx.org\"\n"
 
-      desc 'Prep application.js to include HTMX installation for Webpacker or Sprockets'
+      desc 'Prep application.js to include HTMX installation for Webpacker, Sprockets or Importmap'
 
       # Setup HTMX
       def setup
-        if webpacker?
+        if importmap?
+          setup_importmap
+        elsif webpacker?
           setup_webpacker
-        else
+        elsif sprockets?
           setup_sprockets
+        else
+          raise 'No known asset pipeline detected'
         end
       end
 
@@ -23,10 +28,30 @@ def webpacker?
         !!defined?(Webpacker)
       end
 
+      def sprockets?
+        !!defined?(Sprockets)
+      end
+
+      def importmap?
+        !!defined?(Importmap)
+      end
+
       def manifest(javascript_dir)
         Pathname.new(destination_root).join(javascript_dir, 'application.js')
       end
 
+      def setup_importmap
+        run 'bin/importmap pin htmx.org'
+
+        manifest = manifest('app/javascript')
+
+        if manifest.exist?
+          append_file manifest, "\n#{IMPORTMAP_SETUP}"
+        else
+          create_file manifest, IMPORTMAP_SETUP
+        end
+      end
+
       def setup_sprockets
         manifest = manifest('app/assets/javascripts')
 
@@ -38,7 +63,7 @@ def setup_sprockets
       end
 
       def setup_webpacker
-        `yarn add htmx.org`
+        run 'yarn add htmx.org'
 
         manifest = manifest(webpack_source_path)
 

spec/generators/install_generator_spec.rb

@@ -14,6 +14,12 @@
   after(:all) { FileUtils.rm_rf destination_root }
 
   context 'with Sprockets' do
+    before do
+      hide_const('Webpacker')
+      hide_const('Importmap')
+      stub_const('Sprockets', Module.new)
+    end
+
     context 'when `application.js` exists' do
       before do
         generate_application_js('/app/assets/javascripts')
@@ -42,10 +48,12 @@
   context 'with Webpacker' do
     before do
       stub_const('Webpacker', Module.new)
+      hide_const('Sprockets')
+      hide_const('Importmap')
 
-      Htmx::Generators::InstallGenerator
-        .any_instance
-        .stub(:webpack_source_path)
+      expect_any_instance_of(Htmx::Generators::InstallGenerator)
+        .to receive(:webpack_source_path)
+        .at_least(1).time
         .and_return(File.join("#{destination_root}/app/javascript/packs"))
     end
 
@@ -73,4 +81,48 @@
       end
     end
   end
+
+  context 'with Importmap' do
+    before do
+      hide_const('Webpacker')
+      hide_const('Sprockets')
+      stub_const('Importmap', Module.new)
+    end
+
+    context 'when `application.js` exists' do
+      before do
+        generate_application_js('/app/javascript')
+      end
+
+      it 'updates file with htmx import' do
+        run_generator
+        assert_file(
+          'app/javascript/application.js',
+          "\n#{Htmx::Generators::InstallGenerator::IMPORTMAP_SETUP}"
+        )
+      end
+    end
+
+    context 'when `application.js` does not exists' do
+      it 'creates `application.js` file with htmx import' do
+        run_generator
+        assert_file(
+          'app/javascript/application.js',
+          Htmx::Generators::InstallGenerator::IMPORTMAP_SETUP
+        )
+      end
+    end
+  end
+
+  context 'with no asset pipeline' do
+    before do
+      hide_const('Webpacker')
+      hide_const('Sprockets')
+      hide_const('Importmap')
+    end
+
+    it 'raise an error' do
+      expect { run_generator }.to raise_error('No known asset pipeline detected')
+    end
+  end
 end