Fix template detection for scaffolds

lib/inertia_rails/generators/helper.rb

@@ -4,7 +4,9 @@ module InertiaRails
   module Generators
     module Helper
       class << self
-        def guess_the_default_framework(package_json_path = Rails.root.join('package.json'))
+        DEFAULT_PACKAGE_PATH = Rails.root.join('package.json')
+
+        def guess_the_default_framework(package_json_path = DEFAULT_PACKAGE_PATH)
           package_json = JSON.parse(package_json_path.read)
           dependencies = package_json['dependencies'] || {}
 
@@ -25,8 +27,8 @@ def guess_typescript
           Rails.root.join('tsconfig.json').exist?
         end
 
-        def guess_inertia_template
-          if Rails.root.join('tailwind.config.js').exist? || Rails.root.join('tailwind.config.ts').exist?
+        def guess_inertia_template(package_json_path = DEFAULT_PACKAGE_PATH)
+          if package_json_path.read.include?('"tailwindcss"')
             'inertia_tw_templates'
           else
             'inertia_templates'

spec/fixtures/package_json_files/tailwind_package.json

@@ -0,0 +1,5 @@
+{
+  "devDependencies": {
+    "tailwindcss": "4.0.0"
+  }
+}

spec/generators/generators_helper_spec.rb

@@ -34,4 +34,19 @@
       end
     end
   end
+
+  describe '#guess_inertia_template' do
+    let(:package_json_path) { Pathname.new(File.expand_path("spec/fixtures/package_json_files/#{fixture_file_name}", Dir.pwd)) }
+
+    shared_examples 'template detection' do |file_name, expected_template|
+      let(:fixture_file_name) { file_name }
+
+      it "returns #{expected_template.inspect} when inspect \"#{file_name}\"" do
+        expect(described_class.guess_inertia_template(package_json_path)).to eq(expected_template)
+      end
+    end
+
+    it_behaves_like 'template detection', 'tailwind_package.json', 'inertia_tw_templates'
+    it_behaves_like 'template detection', 'empty_package.json', 'inertia_templates'
+  end
 end