Support multiple Tailwind css files in a project.

README.md

@@ -55,6 +55,11 @@ If you want unminified assets, you can pass a `debug` argument to the rake task,
 Note that you can combine task options, e.g. `rails tailwindcss:watch[debug,poll]`.
 
 
+### Multiple CSS files
+
+If you have a reason to break up your CSS into multiple CSS files (for example application.tailwind.css and admin.tailwind.css), as long as your files match the `*.tailwind.css` convention, then the build and watch tasks will create build files with the `tailwind.` removed.
+
+
 ### Custom inputs or outputs
 
 If you need to use a custom input or output file, you can run `bundle exec tailwindcss` to access the platform-specific executable, and give it your own build options.

lib/tailwindcss/commands.rb

@@ -73,6 +73,29 @@ def watch_command(poll: false, **kwargs)
         end
       end
 
+      def compile_file_command(file:, debug: false, **kwargs)
+        file = Pathname.new(file.to_s)
+        input = file
+        output = Rails.root.join("app/assets/builds", file.basename.sub("tailwind.", ""))
+        config = input.open(&:readline).start_with?("@config") ? nil : Rails.root.join("config/tailwind.config.js")
+        [
+          executable(**kwargs),
+          "-i", input.to_s,
+          "-o", output.to_s
+        ].tap do |command|
+          command << "-c" if config
+          command << config.to_s if config
+          command << "--minify" unless debug
+        end
+      end
+
+      def watch_file_command(poll: false, **kwargs)
+        compile_file_command(**kwargs).tap do |command|
+          command << "-w"
+          command << "-p" if poll
+        end
+      end
+
       def rails_css_compressor?
         defined?(Rails) && Rails&.application&.config&.assets&.css_compressor.present?
       end

lib/tasks/build.rake

@@ -2,18 +2,46 @@ namespace :tailwindcss do
   desc "Build your Tailwind CSS"
   task build: :environment do |_, args|
     debug = args.extras.include?("debug")
-    command = Tailwindcss::Commands.compile_command(debug: debug)
-    puts command.inspect if args.extras.include?("verbose")
-    system(*command, exception: true)
+
+    files = Rails.root.join("app/assets/stylesheets").glob("*.tailwind.css")
+
+    if files.count == 1 && files.first.basename == "application.tailwind.css"
+      command = Tailwindcss::Commands.compile_command(debug: debug)
+      puts command.join(" ")
+      system(*command, exception: true)
+    else
+      files.map do |file|
+        Tailwindcss::Commands.compile_file_command(file: file, debug: debug)
+      end.each do |command|
+        puts command.join(" ")
+        system(*command, exception: true)
+      end
+    end
   end
 
   desc "Watch and build your Tailwind CSS on file changes"
   task watch: :environment do |_, args|
     debug = args.extras.include?("debug")
     poll = args.extras.include?("poll")
-    command = Tailwindcss::Commands.watch_command(debug: debug, poll: poll)
-    puts command.inspect if args.extras.include?("verbose")
-    system(*command)
+
+    files = Rails.root.join("app/assets/stylesheets").glob("*.tailwind.css")
+
+    if files.count == 1 && files.first.basename == "application.tailwind.css"
+      command = Tailwindcss::Commands.watch_command(debug: debug, poll: poll)
+      puts command.join(" ")
+      system(*command)
+    else
+      trap("SIGINT") { exit }
+
+      files.map do |file|
+        Tailwindcss::Commands.watch_file_command(file: file, debug: debug, poll: poll)
+      end.each do |command|
+        fork do
+          puts command.join(" ")
+          system(*command)
+        end
+      end
+    end
   end
 end
 

test/fixtures/application.tailwind.css

@@ -0,0 +1,3 @@
+@tailwind base;
+@tailwind components;
+@tailwind utilities;

test/fixtures/custom.tailwind.css

@@ -0,0 +1,4 @@
+@config "custom.tailwind.config.js";
+@tailwind base;
+@tailwind components;
+@tailwind utilities;

test/lib/tailwindcss/commands_test.rb

@@ -76,6 +76,39 @@ def mock_exe_directory(platform)
     end
   end
 
+
+  test ".compile_file_command" do
+    mock_exe_directory("sparc-solaris2.8") do |dir, executable|
+      Rails.stub(:root, Pathname.new(File.dirname(__FILE__))) do
+        file = Rails.root.join("../../fixtures/application.tailwind.css")
+        actual = Tailwindcss::Commands.compile_file_command(file: file, exe_path: dir)
+        assert_kind_of(Array, actual)
+        assert_equal(executable, actual.first)
+        assert_includes(actual, "--minify")
+        assert_includes(actual, "-c")
+        assert_includes(actual[2], "application.tailwind.css")
+        refute_includes(actual[4], "tailwind.css")
+
+        actual = Tailwindcss::Commands.compile_file_command(file: file, exe_path: dir, debug: true)
+        assert_kind_of(Array, actual)
+        assert_equal(executable, actual.first)
+        assert_includes(actual, "-c")
+        refute_includes(actual, "--minify")
+        assert_includes(actual[2], "application.tailwind.css")
+        refute_includes(actual[4], "tailwind.css")
+
+        file = Rails.root.join("../../fixtures/custom.tailwind.css")
+        actual = Tailwindcss::Commands.compile_file_command(file: file, exe_path: dir)
+        assert_kind_of(Array, actual)
+        assert_equal(executable, actual.first)
+        assert_includes(actual, "--minify")
+        assert_includes(actual[2], "custom.tailwind.css")
+        refute_includes(actual, "-c")
+        refute_includes(actual[4], "tailwind.css")
+      end
+    end
+  end
+
   test ".watch_command" do
     mock_exe_directory("sparc-solaris2.8") do |dir, executable|
       Rails.stub(:root, File) do # Rails.root won't work in this test suite
@@ -102,4 +135,42 @@ def mock_exe_directory(platform)
       end
     end
   end
+
+  test ".watch_file_command" do
+    mock_exe_directory("sparc-solaris2.8") do |dir, executable|
+      Rails.stub(:root, Pathname.new(File.dirname(__FILE__))) do
+        file = Rails.root.join("../../fixtures/application.tailwind.css")
+        actual = Tailwindcss::Commands.watch_file_command(file: file, exe_path: dir)
+        assert_kind_of(Array, actual)
+        assert_equal(executable, actual.first)
+        assert_includes(actual, "-w")
+        assert_includes(actual, "--minify")
+        assert_includes(actual, "-c")
+        assert_includes(actual[2], "application.tailwind.css")
+        refute_includes(actual, "-p")
+        refute_includes(actual[4], "tailwind.css")
+
+        actual = Tailwindcss::Commands.watch_file_command(file: file, exe_path: dir, debug: true)
+        assert_kind_of(Array, actual)
+        assert_equal(executable, actual.first)
+        assert_includes(actual, "-w")
+        assert_includes(actual, "-c")
+        assert_includes(actual[2], "application.tailwind.css")
+        refute_includes(actual, "-p")
+        refute_includes(actual, "--minify")
+        refute_includes(actual[4], "tailwind.css")
+
+        file = Rails.root.join("../../fixtures/custom.tailwind.css")
+        actual = Tailwindcss::Commands.watch_file_command(file: file, exe_path: dir, poll: true)
+        assert_kind_of(Array, actual)
+        assert_equal(executable, actual.first)
+        assert_includes(actual, "-w")
+        assert_includes(actual, "-p")
+        assert_includes(actual, "--minify")
+        assert_includes(actual[2], "custom.tailwind.css")
+        refute_includes(actual, "-c")
+        refute_includes(actual[4], "tailwind.css")
+      end
+    end
+  end
 end