DEV: Add workflow to check production build

At the moment this just checks for the reproducibility of the production build. We may want to extend this workflow in future to check for things like bundle-size, and perhaps run a smoke test of a production-mode site.

.github/workflows/tests.yml

@@ -64,6 +64,8 @@ jobs:
         include:
           - build_type: system
             target: chat
+          - build_type: production-build
+            target: core
 
     steps:
       - name: Set working directory owner
@@ -294,6 +296,12 @@ jobs:
         shell: bash
         timeout-minutes: 30
 
+      - name: Test production build
+        if: matrix.build_type == 'production-build'
+        env: 
+          CHEAP_SOURCE_MAPS: 0 # We want real sourcemaps here
+        run: ./script/check_reproducible_assets.rb
+
       - name: Check for failed system test screenshots
         id: check-failed-system-test-screenshots
         if: always() && matrix.build_type == 'system'

script/check_reproducible_assets.rb

@@ -8,6 +8,7 @@
 require "digest"
 
 DIST_DIR = File.expand_path("#{__dir__}/../app/assets/javascripts/discourse/dist")
+DIST_1_DIR = File.expand_path("#{__dir__}/../app/assets/javascripts/discourse/dist1")
 
 def collect_asset_info
   files =
@@ -15,15 +16,28 @@ def collect_asset_info
   puts "Found #{files.length} files"
   raise "No files found" if files.empty?
   digests = files.map { |file| Digest::MD5.file("#{DIST_DIR}/#{file}").hexdigest }
-  { files: files, digests: digests }
+  sizes = files.map { |file| [file, File.size("#{DIST_DIR}/#{file}") / 8 / 1024] }.to_h
+  { files: files, digests: digests, sizes: sizes }
+end
+
+def print_details(files, size_dict)
+  files.each { |file| puts " - #{file} (#{size_dict[file]}kb)" }
 end
 
 puts "Running first build..."
-system "#{__dir__}/../bin/yarn-app ember build -prod", exception: true
+system "cd #{__dir__}/.. && pnpm ember build -prod", exception: true
 first_build_info = collect_asset_info
+system "rm", "-rf", DIST_1_DIR, exception: true
+system "mv", DIST_DIR, DIST_1_DIR, exception: true
 
 puts "Running second build..."
-system "#{__dir__}/../bin/yarn-app ember build -prod", exception: true
+Dir.chdir("#{__dir__}/../app/assets/javascripts/discourse") do # rubocop:disable Discourse/NoChdir
+  system "/bin/bash",
+         "-c",
+         "shopt -s nullglob; rm -rf $TMPDIR/embroider $TMPDIR/.broccoli-* node_modules/.embroider",
+         exception: true
+end
+system "cd #{__dir__}/.. && pnpm ember build -prod", exception: true
 second_build_info = collect_asset_info
 
 puts nil, nil, "Comparing builds...", nil, nil
@@ -32,10 +46,12 @@ if first_build_info[:files] != second_build_info[:files]
   puts "Set of files is different"
 
   new_assets = first_build_info[:files].difference(second_build_info[:files])
-  puts "Second build had additional assets: #{new_assets.inspect}"
+  puts "Second build had additional assets:"
+  print_details(new_assets, first_build_info[:sizes])
 
   missing_assets = second_build_info[:files].difference(first_build_info[:files])
-  puts "Second build was missing assets: #{missing_assets.inspect}"
+  puts "Second build was missing assets:"
+  print_details(missing_assets, second_build_info[:sizes])
 
   exit 1
 else