discourse/lib/plugin.rb

# frozen_string_literal: true

module Plugin
  def self.initialization_guard(&block)
    begin
      block.call
    rescue => error
      plugins_directory = Rails.root + 'plugins'

      if error.backtrace && error.backtrace_locations
        plugin_path = error.backtrace_locations.lazy.map do |location|
          Pathname.new(location.absolute_path)
            .ascend
            .lazy
            .find { |path| path.parent == plugins_directory }
        end.next

        raise unless plugin_path

        stack_trace = error.backtrace.each_with_index.inject([]) do |messages, (line, index)|
          if index == 0
            messages << "#{line}: #{error} (#{error.class})"
          else
            messages << "\t#{index}: from #{line}"
          end
        end.reverse.join("\n")

        STDERR.puts <<~TEXT
          #{stack_trace}

          ** INCOMPATIBLE PLUGIN **

          You are unable to build Discourse due to errors in the plugin at
          #{plugin_path}

          Please try removing this plugin and rebuilding again!
        TEXT
      else
        STDERR.puts <<~TEXT
          ** PLUGIN FAILURE **

          You are unable to build Discourse due to this error during plugin
          initialization:

          #{error}

          #{error.backtrace.join("\n")}
        TEXT
      end
      exit 1
    end
  end
end