Changing attr in preprocess does not cause outdatedness

[denisdefreyne]

Steps to reproduce

Given:

• an item /cv/ with Haml contents

  - items.find_all('/talks/*/').each do |post|
  %li
      - p post
      = post.identifier
      = post[:status]

• a few items:

  • /talks/aaa/
  • /talks/bbb/

• a Rules file

  #!/usr/bin/env ruby
  
  preprocess do
    items.each do |i|
      if i.identifier =~ /talks/
        i[:status] = 'archive'
      else
        i[:status] = 'current'
      end
    end
  end
  
  compile '/**/*/' do
    case item[:extension]
    when 'md'
      filter :kramdown
    when 'haml'
      filter :haml
    end
  
    write item.identifier + 'index.html'
  end
  
  layout '/**/*', :haml

When:

1. Compiling the site
2. Changing the condition in the preprocessor to if i.identifier =~ /aaa/
3. Compiling the site again

Expected behavior

output/cv/index.html is updated (containing “archived” for /aaa/ but “current” for /bbb/)

Actual behavior

output/cv/index.html is not updated (containing “current” for /aaa/ and /bbb/)

Details

When mutating attributes and/or content, checksum_data, attributes_checksum_data and content_checksum_data is not invalidated. It should be.