switch to email_reply_trimmer from discourse

Gemfile

@@ -332,7 +332,7 @@ gem 'octokit', '~> 4.3.0'
 gem 'mail_room', '~> 0.9.0'
-gem 'email_reply_parser', '~> 0.5.8'
+gem 'email_reply_trimmer', '~> 0.1'
 gem 'html2text'
 gem 'ruby-prof', '~> 0.16.2'

Gemfile.lock

@@ -167,7 +167,7 @@ GEM
       railties (>= 4.2)
     dropzonejs-rails (0.7.2)
       rails (> 3.1)
-    email_reply_parser (0.5.8)
+    email_reply_trimmer (0.1.6)
     email_spec (1.6.0)
       launchy (~> 2.1)
       mail (~> 2.2)
@@ -839,7 +839,7 @@ DEPENDENCIES
   diffy (~> 3.1.0)
   doorkeeper (~> 4.2.0)
   dropzonejs-rails (~> 0.7.1)
-  email_reply_parser (~> 0.5.8)
+  email_reply_trimmer (~> 0.1)
   email_spec (~> 1.6.0)
   factory_girl_rails (~> 4.7.0)
   ffaker (~> 2.0.0)

lib/gitlab/email/reply_parser.rb

@@ -13,9 +13,11 @@ module Gitlab
         encoding = body.encoding
-        body = discourse_email_trimmer(body)
-        body = EmailReplyParser.parse_reply(body)
+        body = EmailReplyTrimmer.trim(body)
+        # TODO [jneen]: do we want to allow empty-quoting? (replies only containing a blockquote)
+        # EmailReplyTrimmer allows this as a special case, so we detect it manually here.
+        return "" if body.lines.all? { |l| l.strip.empty? || l.start_with?('>') }
         body.force_encoding(encoding).encode("UTF-8")
       end
@@ -57,30 +59,6 @@ module Gitlab
       rescue
         nil
       end
-
-      REPLYING_HEADER_LABELS = %w(From Sent To Subject Reply To Cc Bcc Date)
-      REPLYING_HEADER_REGEX = Regexp.union(REPLYING_HEADER_LABELS.map { |label| "#{label}:" })
-
-      def discourse_email_trimmer(body)
-        lines = body.scrub.lines.to_a
-        range_end = 0
-
-        lines.each_with_index do |l, idx|
-          # This one might be controversial but so many reply lines have years, times and end with a colon.
-          # Let's try it and see how well it works.
-          break if (l =~ /\d{4}/ && l =~ /\d:\d\d/ && l =~ /\:$/) ||
-              (l =~ /On \w+ \d+,? \d+,?.*wrote:/)
-
-          # Headers on subsequent lines
-          break if (0..2).all? { |off| lines[idx + off] =~ REPLYING_HEADER_REGEX }
-          # Headers on the same line
-          break if REPLYING_HEADER_LABELS.count { |label| l.include?(label) } >= 3
-
-          range_end = idx
-        end
-
-        lines[0..range_end].join.strip
-      end
     end
   end
 end

spec/lib/gitlab/email/reply_parser_spec.rb

@@ -88,8 +88,6 @@ describe Gitlab::Email::ReplyParser, lib: true do
       expect(test_parse_body(fixture_file("emails/inline_reply.eml"))).
         to eq(
           <<-BODY.strip_heredoc.chomp
-            On Wed, Oct 8, 2014 at 11:12 AM, techAPJ <info@unconfigured.discourse.org> wrote:
-
             >     techAPJ <https://meta.discourse.org/users/techapj>
             > November 28
             >
@@ -158,7 +156,7 @@ describe Gitlab::Email::ReplyParser, lib: true do
           <<-BODY.strip_heredoc.chomp
             ### this is a reply from iOS default mail
-            The quick brown fox jumps over the lazy dog. The quick brown fox jumps over the lazy dog. The quick brown fox jumps over the lazy dog. The quick brown fox jumps over the lazy dog. The quick brown fox jumps over the lazy dog. The quick brown fox jumps over the lazy dog. The quick brown fox jumps over the lazy dog.
+            The quick brown fox jumps over the lazy dog. The quick brown fox jumps over the lazy dog. The quick brown fox jumps over the lazy dog. The quick brown fox jumps over the lazy dog. The quick brown fox jumps over the lazy dog. The quick brown fox jumps over the lazy dog. The quick brown fox jumps over the lazy dog. 
             Here's some **bold** markdown text.