DEV: perform theme extra_js compilation all together

Previously, compiling theme 'extra_js' was done with a number of steps. Each theme_field would be compiled into its own value_baked column, and then the JavascriptCache content would be built by concatenating all of those compiled values.

This commit streamlines things by removing the value_baked step. The raw value of all extra_js theme_fields are passed directly to the ThemeJavascriptCompiler, and then the result is stored in the JavascriptCache.

In itself, this commit should not cause any behavior change. It is designed to open the door to more advanced compilation features which have interdependencies between different source files (e.g. template colocation, sourcemaps).

lib/theme_javascript_compiler.rb

@@ -25,6 +25,38 @@ class ThemeJavascriptCompiler
     JS
   end
 
+  def append_tree(tree, for_tests: false)
+    root_name = "discourse"
+
+    # Replace legacy extensions
+    tree.transform_keys! do |filename|
+      if filename.ends_with? ".js.es6"
+        filename.sub(/\.js\.es6\z/, ".js")
+      elsif filename.ends_with? ".raw.hbs"
+        filename.sub(/\.raw\.hbs\z/, ".hbr")
+      else
+        filename
+      end
+    end
+
+    # Transpile and write to output
+    tree.each_pair do |filename, content|
+      module_name, extension = filename.split(".", 2)
+      module_name = "test/#{module_name}" if for_tests
+      if extension == "js"
+        append_module(content, module_name)
+      elsif extension == "hbs"
+        append_ember_template(module_name, content)
+      elsif extension == "hbr"
+        append_raw_template(module_name.sub("discourse/templates/", ""), content)
+      else
+        append_js_error("unknown file extension '#{extension}' (#{filename})")
+      end
+    rescue CompileError => e
+      append_js_error "#{e.message} (#{filename})"
+    end
+  end
+
   def append_ember_template(name, hbs_template)
     name = "/#{name}" if !name.start_with?("/")
     module_name = "discourse/theme-#{@theme_id}#{name}"
@@ -93,7 +125,8 @@ class ThemeJavascriptCompiler
   end
 
   def append_js_error(message)
-    @content << "console.error('Theme Transpilation Error:', #{message.inspect});"
+    message = "[THEME #{@theme_id} '#{@theme_name}'] Compile error: #{message}"
+    append_raw_script "console.error(#{message.to_json});"
   end
 
   private