DEV: Plugins can extend color definitions (#10383)

lib/discourse_plugin_registry.rb

@@ -54,6 +54,7 @@ class DiscoursePluginRegistry
   define_register :stylesheets, Hash
   define_register :mobile_stylesheets, Hash
   define_register :desktop_stylesheets, Hash
+  define_register :color_definition_stylesheets, Hash
   define_register :sass_variables, Set
   define_register :handlebars, Set
   define_register :serialized_current_user_fields, Set
@@ -153,6 +154,8 @@ class DiscoursePluginRegistry
       elsif opts == :desktop
         self.desktop_stylesheets[plugin_directory_name] ||= Set.new
         self.desktop_stylesheets[plugin_directory_name] << asset
+      elsif opts == :color_definitions
+        self.color_definition_stylesheets[plugin_directory_name] = asset
       elsif opts == :variables
         self.sass_variables << asset
       else

lib/stylesheet/compiler.rb

@@ -19,6 +19,10 @@ module Stylesheet
         filename = "#{asset}.scss"
         path = "#{Stylesheet::Common::ASSET_ROOT}/#{filename}"
         file = File.read path
+
+        if asset.to_s == Stylesheet::Manager::COLOR_SCHEME_STYLESHEET
+          file += Stylesheet::Importer.import_color_definitions
+        end
       end
 
       compile(file, filename, options)

lib/stylesheet/importer.rb

@@ -115,6 +115,17 @@ module Stylesheet
 
     register_imports!
 
+    def self.import_color_definitions
+      return "" unless DiscoursePluginRegistry.color_definition_stylesheets.length
+      contents = +""
+      DiscoursePluginRegistry.color_definition_stylesheets.each do |name, path|
+        contents << "// Color definitions from #{name}\n\n"
+        contents << File.read(path.to_s)
+        contents << "\n\n"
+      end
+      contents
+    end
+
     def initialize(options)
       @theme = options[:theme]
       @theme_id = options[:theme_id]

spec/components/discourse_plugin_registry_spec.rb

@@ -227,6 +227,12 @@ describe DiscoursePluginRegistry do
       expect(registry.stylesheets[plugin_directory_name]).to eq(nil)
     end
 
+    it "registers color definitions properly" do
+      registry.register_asset("test.css", :color_definitions, plugin_directory_name)
+      expect(registry.color_definition_stylesheets[plugin_directory_name]).to eq('test.css')
+      expect(registry.stylesheets[plugin_directory_name]).to eq(nil)
+    end
+
     it "registers sass variable properly" do
       registry.register_asset("test.css", :variables)
 

spec/components/plugin/instance_spec.rb

@@ -11,8 +11,8 @@ describe Plugin::Instance do
   context "find_all" do
     it "can find plugins correctly" do
       plugins = Plugin::Instance.find_all("#{Rails.root}/spec/fixtures/plugins")
-      expect(plugins.count).to eq(3)
+      expect(plugins.count).to eq(4)
-      plugin = plugins[2]
+      plugin = plugins[3]
 
       expect(plugin.name).to eq("plugin-name")
       expect(plugin.path).to eq("#{Rails.root}/spec/fixtures/plugins/my_plugin/plugin.rb")

spec/components/stylesheet/compiler_spec.rb

@@ -84,5 +84,26 @@ describe Stylesheet::Compiler do
       expect(css).to include("--header_primary: #88af8e")
       expect(css).to include("--header_background-rgb: 248,116,92")
     end
+
+    context "with a plugin" do
+      before do
+        plugin = Plugin::Instance.new
+        plugin.path = "#{Rails.root}/spec/fixtures/plugins/color_definition/plugin.rb"
+        Discourse.plugins << plugin
+        plugin.activate!
+      end
+
+      after do
+        Discourse.plugins.pop
+        DiscoursePluginRegistry.reset!
+      end
+
+      it "includes color definitions from plugins" do
+        css, _map = Stylesheet::Compiler.compile_asset("color_definitions")
+
+        expect(css).to include("--plugin-color")
+      end
+    end
+
   end
 end

spec/fixtures/plugins/color_definition/assets/stylesheets/colors.scss

@@ -0,0 +1,3 @@
+:root {
+  --plugin-color: #{$primary};
+}

spec/fixtures/plugins/color_definition/plugin.rb

@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+# name: color_definition
+# about: Fixture plugin that extends color definitions
+# version: 1.0
+# authors: pmusaraj
+
+register_asset "stylesheets/colors.scss", :color_definitions