Detect Containerfiles as Dockerfiles (rouge-ruby#2059)

Co-authored-by: Andrew Hills <[email protected]>

Author: ahills

lib/rouge/lexers/docker.rb

@@ -7,8 +7,8 @@ class Docker < RegexLexer
       title "Docker"
       desc "Dockerfile syntax"
       tag 'docker'
-      aliases 'dockerfile', 'Dockerfile'
-      filenames 'Dockerfile', '*.Dockerfile', '*.docker'
+      aliases 'dockerfile', 'Dockerfile', 'containerfile', 'Containerfile'
+      filenames 'Dockerfile', '*.Dockerfile', '*.docker', 'Containerfile', '*.Containerfile'
       mimetypes 'text/x-dockerfile-config'
 
       KEYWORDS = %w(

spec/lexers/docker_spec.rb

@@ -11,6 +11,8 @@
       assert_guess :filename => 'Dockerfile'
       assert_guess :filename => 'docker.docker'
       assert_guess :filename => 'some.Dockerfile'
+      assert_guess :filename => 'Containerfile'
+      assert_guess :filename => 'some.Containerfile'
     end
 
     it 'guesses by mimetype' do