Use vendor/javascript instead of app/javascript/vendor

Author: David Heinemeier Hansson

lib/importmap/engine.rb

@@ -26,7 +26,9 @@ class Engine < ::Rails::Engine
 
     initializer "importmap.cache_sweeper" do |app|
       if app.config.importmap.sweep_cache
-        app.importmap.cache_sweeper watches: app.root.join("app/javascript")
+        app.importmap.cache_sweeper watches: [ 
+          app.root.join("app/javascript"), app.root.join("vendor/javascript")
+        ]
 
         ActiveSupport.on_load(:action_controller_base) do
           before_action { Rails.application.importmap.cache_sweeper.execute_if_updated }
@@ -38,6 +40,7 @@ class Engine < ::Rails::Engine
       if Rails.application.config.respond_to?(:assets)
         Rails.application.config.assets.precompile += %w( es-module-shims.js es-module-shims.min.js )
         Rails.application.config.assets.paths << Rails.root.join("app/javascript")
+        Rails.application.config.assets.paths << Rails.root.join("vendor/javascript")
       end
     end
 

lib/importmap/packager.rb

@@ -10,9 +10,9 @@ class Importmap::Packager
   singleton_class.attr_accessor :endpoint
   self.endpoint = URI("https://api.jspm.io/generate")
 
-  def initialize(importmap_path = "config/importmap.rb", vendor_path: Pathname.new("app/javascript/vendor"))
-    @importmap_path = importmap_path
-    @vendor_path    = vendor_path
+  def initialize(importmap_path = "config/importmap.rb", vendor_path: "vendor/javascript")
+    @importmap_path = Pathname.new(importmap_path)
+    @vendor_path    = Pathname.new(vendor_path)
   end
 
   def import(*packages, env: "production", from: "jspm")