FEATURE: automatically elides gmail quotes

lib/email/receiver.rb

@@ -261,9 +261,16 @@ module Email
       end
 
       markdown, elided_markdown = if html.present?
-        markdown = HtmlToMarkdown.new(html, keep_img_tags: true, keep_cid_imgs: true).to_markdown
-        markdown = trim_discourse_markers(markdown)
-        trim_reply_and_extract_elided(markdown)
+        if html[%{<div class="gmail_quote">}]
+          html, elided_html = extract_gmail_quote(html)
+          markdown = HtmlToMarkdown.new(html, keep_img_tags: true, keep_cid_imgs: true).to_markdown
+          elided_markdown = HtmlToMarkdown.new(elided_html).to_markdown
+          [markdown, elided_markdown]
+        else
+          markdown = HtmlToMarkdown.new(html, keep_img_tags: true, keep_cid_imgs: true).to_markdown
+          markdown = trim_discourse_markers(markdown)
+          trim_reply_and_extract_elided(markdown)
+        end
       end
 
       if text.blank? || (SiteSetting.incoming_email_prefer_html && markdown.present?)
@@ -273,6 +280,12 @@ module Email
       end
     end
 
+    def extract_gmail_quote(html)
+      doc = Nokogiri::HTML.fragment(html)
+      elided = doc.css("div.gmail_quote")[0].remove
+      [doc.to_html, elided.to_html]
+    end
+
     def trim_reply_and_extract_elided(text)
       return [text, ""] if @opts[:skip_trimming]
       EmailReplyTrimmer.trim(text, true)

spec/components/email/receiver_spec.rb

@@ -191,6 +191,12 @@ describe Email::Receiver do
       expect(topic.posts.last.raw).to eq("This is a **HTML** reply ;)")
     end
 
+    it "automatically elides gmail quotes" do
+      SiteSetting.always_show_trimmed_content = true
+      expect { process(:gmail_html_reply) }.to change { topic.posts.count }
+      expect(topic.posts.last.raw).to eq("This is a **GMAIL** reply ;)\n\n<details class='elided'>\n<summary title='Show trimmed content'>&#183;&#183;&#183;</summary>\n\nThis is the *elided* part!\n\n</details>")
+    end
+
     it "doesn't process email with same message-id more than once" do
       expect do
         process(:text_reply)

spec/fixtures/emails/gmail_html_reply.eml

@@ -0,0 +1,17 @@
+Return-Path: <discourse@bar.com>
+From: Foo Bar <discourse@bar.com>
+To: alt+4f97315cc828096c9cb34c6f1a0d6fe8@bar.com
+Date: Fri, 15 Jan 2016 00:12:43 +0100
+Message-ID: <180@foo.bar.mail>
+Mime-Version: 1.0
+Content-Type: text/html; charset=UTF-8
+Content-Transfer-Encoding: quoted-printable
+
+<div>
+  <div dir="auto">
+    <p>This is a <b>GMAIL</b> reply ;)</p>
+  </div>
+  <div class="gmail_quote">
+    <p>This is the <i>elided</i> part!</p>
+  </div>
+</div>