From 7b3161f00da6ef4a953d8005896b242aead865a4 Mon Sep 17 00:00:00 2001
From: Jonathan del Strother <me@delstrother.com>
Date: Tue, 29 Oct 2024 13:46:13 +0000
Subject: [PATCH] Allow loading webpack.config.ts if present

---
 CHANGELOG.md                            |  1 +
 lib/shakapacker/runner.rb               | 21 +++++++++++++++------
 spec/shakapacker/webpack_runner_spec.rb | 11 +++++++++++
 3 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index b83e664c..28659ac8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,7 @@ Changes since the last non-beta release.
 
 ### Changed
 - Changed internal `require`s to `require_relative` to make code less dependent on the load path. [PR 516](https://github.com/shakacode/shakapacker/pull/516) by [tagliala](https://github.com/tagliala).
+- Allow configuring webpack from a Typescript file (`config/webpack/webpack.config.ts`). [PR 524](https://github.com/shakacode/shakapacker/pull/524) by [jdelStrother](https://github.com/jdelStrother).
 
 ### Fixed
 - Fix error when rails environment is required from outside the rails root directory [PR 520](https://github.com/shakacode/shakapacker/pull/520)
diff --git a/lib/shakapacker/runner.rb b/lib/shakapacker/runner.rb
index 27785a18..d6ffa879 100644
--- a/lib/shakapacker/runner.rb
+++ b/lib/shakapacker/runner.rb
@@ -15,13 +15,8 @@ def initialize(argv)
       @argv = argv
 
       @app_path              = File.expand_path(".", Dir.pwd)
-      @webpack_config        = File.join(@app_path, "config/webpack/webpack.config.js")
       @shakapacker_config    = ENV["SHAKAPACKER_CONFIG"] || File.join(@app_path, "config/shakapacker.yml")
-
-      unless File.exist?(@webpack_config)
-        $stderr.puts "webpack config #{@webpack_config} not found, please run 'bundle exec rails shakapacker:install' to install Shakapacker with default configs or add the missing config file for your custom environment."
-        exit!
-      end
+      @webpack_config        = find_webpack_config
 
       Shakapacker::Utils::Manager.error_unless_package_manager_is_obvious!
     end
@@ -29,5 +24,19 @@ def initialize(argv)
     def package_json
       @package_json ||= PackageJson.read(@app_path)
     end
+
+    private
+
+    def find_webpack_config
+      possible_paths = %w[ts js].map do |ext|
+        File.join(@app_path, "config/webpack/webpack.config.#{ext}")
+      end
+      path = possible_paths.find { |f| File.exist?(f) }
+      unless path
+        $stderr.puts "webpack config #{possible_paths.last} not found, please run 'bundle exec rails shakapacker:install' to install Shakapacker with default configs or add the missing config file for your custom environment."
+        exit!
+      end
+      path
+    end
   end
 end
diff --git a/spec/shakapacker/webpack_runner_spec.rb b/spec/shakapacker/webpack_runner_spec.rb
index 09f79f9c..a9db479a 100644
--- a/spec/shakapacker/webpack_runner_spec.rb
+++ b/spec/shakapacker/webpack_runner_spec.rb
@@ -54,6 +54,17 @@
 
         verify_command(cmd, argv: (["--watch"]))
       end
+
+      it "loads webpack.config.ts if present" do
+        ts_config = "#{test_app_path}/config/webpack/webpack.config.ts"
+        FileUtils.touch(ts_config)
+
+        cmd = package_json.manager.native_exec_command("webpack", ["--config", ts_config])
+
+        verify_command(cmd)
+      ensure
+        FileUtils.rm(ts_config)
+      end
     end
   end