Added support for use in Rails engines

lib/rails_icons/icon.rb

@@ -1,3 +1,4 @@
+require "rails_icons/icon/file_path"
 require "rails_icons/icon/attributes"
 
 class RailsIcons::Icon
@@ -35,19 +36,7 @@ def error_message
     "Icon not found: `#{attributes.join(" / ")}`"
   end
 
-  def file_path
-    return RailsIcons::Engine.root.join("app", "assets", "svg", "rails_icons", "icons", "animated", "#{@name}.svg") if @library.animated?
-    return Rails.root.join(custom_library.dig(:path), "#{@name}.svg") if custom_library?
-
-    parts = [
-      RailsIcons.configuration.destination_path,
-      @library,
-      @variant,
-      "#{@name}.svg"
-    ].compact_blank!
-
-    Rails.root.join(*parts)
-  end
+  def file_path = RailsIcons::Icon::FilePath.new(name: @name, library: @library, variant: @variant).call
 
   def attach_attributes(to:)
     RailsIcons::Icon::Attributes

lib/rails_icons/icon/file_path.rb

@@ -0,0 +1,57 @@
+module RailsIcons
+  class Icon
+    class FilePath
+      def initialize(name:, library:, variant:)
+        @name = name
+        @library = library
+        @variant = variant
+      end
+
+      def call
+        return animated_icons_path if @library.animated?
+        return custom_library_path if @library.custom?
+
+        icon_path = icons_path_in_app || icons_path_in_engines
+
+        raise RailsIcons::NotFound if icon_path.nil?
+
+        icon_path
+      end
+
+      private
+
+      def animated_icons_path = RailsIcons::Engine.root.join("app", "assets", "svg", "rails_icons", "icons", "animated", "#{@name}.svg")
+
+      def custom_library_path = Rails.root.join(@library.custom_path, "#{@name}.svg")
+
+      def icons_path_in_app
+        path = app_path
+
+        path if File.exist?(path)
+      end
+
+      def icons_path_in_engines
+        path = nil
+
+        Rails::Engine.subclasses.find do |engine|
+          path = engine.root.join(*parts)
+
+          path if File.exist?(path)
+        end
+
+        path
+      end
+
+      def app_path = Rails.root.join(*parts)
+
+      def parts
+        [
+          RailsIcons.configuration.destination_path,
+          @library,
+          @variant,
+          "#{@name}.svg"
+        ].compact_blank!
+      end
+    end
+  end
+end