Add --preload option to pin command

Appraisals

@@ -11,19 +11,37 @@ end
 appraise "rails_7_1_sprockets" do
   gem "rails", "~> 7.1.0"
   gem "sprockets-rails"
+
+  group :test do
+    remove_gem "concurrent-ruby"
+  end
 end
 
 appraise "rails_7_1_propshaft" do
   gem "rails", "~> 7.1.0"
   gem "propshaft"
+
+  group :test do
+    remove_gem "concurrent-ruby"
+  end
 end
 
 appraise "rails_main_sprockets" do
   gem "rails", github: "rails/rails", branch: "main"
   gem "sprockets-rails"
+  gem "sqlite3", ">= 2.1"
+
+  group :test do
+    remove_gem "concurrent-ruby"
+  end
 end
 
 appraise "rails_main_propshaft" do
   gem "rails", github: "rails/rails", branch: "main"
   gem "propshaft"
+  gem "sqlite3", ">= 2.1"
+
+  group :test do
+    remove_gem "concurrent-ruby"
+  end
 end

Gemfile

@@ -22,4 +22,6 @@ group :test do
   gem "capybara"
   gem "selenium-webdriver"
   gem "webdrivers"
+
+  gem "concurrent-ruby", "1.3.4"
 end

Gemfile.lock

@@ -213,6 +213,7 @@ DEPENDENCIES
   appraisal
   byebug
   capybara
+  concurrent-ruby (= 1.3.4)
   importmap-rails!
   rails (~> 6.1.0)
   rexml

gemfiles/rails_7_0_propshaft.gemfile

@@ -18,6 +18,7 @@ group :test do
   gem "capybara"
   gem "selenium-webdriver"
   gem "webdrivers"
+  gem "concurrent-ruby", "1.3.4"
 end
 
 gemspec path: "../"

gemfiles/rails_7_0_propshaft.gemfile.lock

@@ -219,6 +219,7 @@ DEPENDENCIES
   appraisal
   byebug
   capybara
+  concurrent-ruby (= 1.3.4)
   importmap-rails!
   propshaft
   rails (~> 7.0.0)

gemfiles/rails_7_0_sprockets.gemfile

@@ -18,6 +18,7 @@ group :test do
   gem "capybara"
   gem "selenium-webdriver"
   gem "webdrivers"
+  gem "concurrent-ruby", "1.3.4"
 end
 
 gemspec path: "../"

gemfiles/rails_7_0_sprockets.gemfile.lock

@@ -221,6 +221,7 @@ DEPENDENCIES
   appraisal
   byebug
   capybara
+  concurrent-ruby (= 1.3.4)
   importmap-rails!
   rails (~> 7.0.0)
   rexml

gemfiles/rails_main_propshaft.gemfile

@@ -3,7 +3,7 @@
 source "https://rubygems.org"
 
 gem "rails", branch: "main", git: "https://github.com/rails/rails.git"
-gem "sqlite3"
+gem "sqlite3", ">= 2.1"
 gem "propshaft"
 
 group :development do

gemfiles/rails_main_sprockets.gemfile

@@ -3,7 +3,7 @@
 source "https://rubygems.org"
 
 gem "rails", branch: "main", git: "https://github.com/rails/rails.git"
-gem "sqlite3"
+gem "sqlite3", ">= 2.1"
 gem "sprockets-rails"
 
 group :development do

lib/importmap/commands.rb

@@ -12,12 +12,13 @@ def self.exit_on_failure?
   desc "pin [*PACKAGES]", "Pin new packages"
   option :env, type: :string, aliases: :e, default: "production"
   option :from, type: :string, aliases: :f, default: "jspm"
+  option :preload, type: :string, repeatable: true, desc: "Can be used multiple times"
   def pin(*packages)
     if imports = packager.import(*packages, env: options[:env], from: options[:from])
       imports.each do |package, url|
         puts %(Pinning "#{package}" to #{packager.vendor_path}/#{package}.js via download from #{url})
         packager.download(package, url)
-        pin = packager.vendored_pin_for(package, url)
+        pin = packager.vendored_pin_for(package, url, options[:preload])
 
         if packager.packaged?(package)
           gsub_file("config/importmap.rb", /^pin "#{package}".*$/, pin, verbose: false)

lib/importmap/packager.rb

@@ -36,14 +36,14 @@ def pin_for(package, url)
     %(pin "#{package}", to: "#{url}")
   end
 
-  def vendored_pin_for(package, url)
+  def vendored_pin_for(package, url, preloads = nil)
     filename = package_filename(package)
     version  = extract_package_version_from(url)
 
     if "#{package}.js" == filename
-      %(pin "#{package}" # #{version})
+      %(pin "#{package}"#{preload(preloads)} # #{version})
     else
-      %(pin "#{package}", to: "#{filename}" # #{version})
+      %(pin "#{package}", to: "#{filename}"#{preload(preloads)} # #{version})
     end
   end
 
@@ -63,6 +63,16 @@ def remove(package)
   end
 
   private
+    def preload(preloads)
+      case Array(preloads)
+      in [] then ""
+      in ["true"] then %(, preload: true)
+      in ["false"] then %(, preload: false)
+      in [string] then %(, preload: "#{string}")
+      else %(, preload: #{preloads})
+      end
+    end
+
     def post_json(body)
       Net::HTTP.post(self.class.endpoint, body.to_json, "Content-Type" => "application/json")
     rescue => error

test/installer_test.rb

@@ -55,13 +55,21 @@ def with_new_rails_app
         Rails::Generators::AppGenerator.start([app_dir, "--quiet", "--skip-bundle", "--skip-bootsnap"])
 
         Dir.chdir(app_dir) do
+          if Rails::VERSION::PRE == "alpha" && Gem.loaded_specs["sprockets-rails"]
+            FileUtils.mkdir_p("app/assets/config")
+            File.write("app/assets/config/manifest.js", "")
+          end
+
           gemfile = File.read("Gemfile")
-          gemfile.gsub!(/^gem "importmap-rails".*/, "")
-          gemfile << %(gem "importmap-rails", path: #{File.expand_path("..", __dir__).inspect}\n)
+          if Gem.loaded_specs["rails"].version < Gem::Version.new("7.1")
+            gemfile << %(gem "concurrent-ruby", "1.3.4"\n)
+          end
           if Rails::VERSION::PRE == "alpha"
             gemfile.gsub!(/^gem "rails".*/, "")
             gemfile << %(gem "rails", path: #{Gem.loaded_specs["rails"].full_gem_path.inspect}\n)
           end
+          gemfile.gsub!(/^gem "importmap-rails".*/, "")
+          gemfile << %(gem "importmap-rails", path: #{File.expand_path("..", __dir__).inspect}\n)
           File.write("Gemfile", gemfile)
 
           run_command("bundle", "install")

test/packager_test.rb

@@ -54,5 +54,9 @@ def code() "200" end
   test "vendored_pin_for" do
     assert_equal %(pin "react" # @17.0.2), @packager.vendored_pin_for("react", "https://cdn/[email protected]")
     assert_equal %(pin "javascript/react", to: "javascript--react.js" # @17.0.2), @packager.vendored_pin_for("javascript/react", "https://cdn/[email protected]")
+    assert_equal %(pin "react", preload: true # @17.0.2), @packager.vendored_pin_for("react", "https://cdn/[email protected]", ["true"])
+    assert_equal %(pin "react", preload: false # @17.0.2), @packager.vendored_pin_for("react", "https://cdn/[email protected]", ["false"])
+    assert_equal %(pin "react", preload: "foo" # @17.0.2), @packager.vendored_pin_for("react", "https://cdn/[email protected]", ["foo"])
+    assert_equal %(pin "react", preload: ["foo", "bar"] # @17.0.2), @packager.vendored_pin_for("react", "https://cdn/[email protected]", ["foo", "bar"])
   end
 end