Cleanup unicode emojis from email headers

Some email providers (for example gmail) block emails if they have
emojis in the from header, as they could be confused with UI elements.
So the easy solution is to just filter all emojis from the name.

The normal `\p{Emoji}` selector also matches normal numbers, because of
the emoji-version of numbers (1️⃣), but the `\p{Emoji_Presentation}` then
doesn't match colored emojis anymore (❄️), so we need a mix of both to
find all emojis

app/mailers/notification_mailers/base.rb

@@ -36,15 +36,23 @@ module NotificationMailers
 
     def default_headers
       from_name = AppConfig.settings.pod_name
-      from_name += " (#{@sender.profile.full_name.empty? ? @sender.username : @sender.name})" if @sender.present?
+      from_name += " (#{person_name(@sender)})" if @sender.present?
 
       {
         from:          name_and_address(from_name, AppConfig.mail.sender_address),
-        to:            name_and_address(@recipient.name, @recipient.email),
+        to:            name_and_address(person_name(@recipient), @recipient.email),
         template_name: self.class.name.demodulize.underscore
       }
     end
 
+    def person_name(person)
+      if person.profile.full_name.empty?
+        person.username
+      else
+        person.name.gsub(/\p{Emoji}\uFE0F\u20E3?|\p{Emoji_Presentation}/, "").strip
+      end
+    end
+
     def with_recipient_locale(&block)
       I18n.with_locale(@recipient.language, &block)
     end

spec/mailers/notifier_spec.rb

@@ -262,6 +262,11 @@ describe Notifier, type: :mailer do
       expect(@mail["From"].to_s).to eq("\"#{pod_name} (#{@cnv.author.name})\" <#{AppConfig.mail.sender_address}>")
     end
 
+    it "FROM: removes emojis from sender's name" do
+      bob.person.profile.update!(first_name: "1️⃣2️3️⃣ Numbers 123", last_name: "👍✅👍🏻Emojis😀😇❄️")
+      expect(@mail["From"].to_s).to eq("\"#{pod_name} (Numbers 123 Emojis)\" <#{AppConfig.mail.sender_address}>")
+    end
+
     it "should use a generic subject" do
       expect(@mail.subject).to eq(I18n.translate("notifier.private_message.subject"))
     end
@@ -302,6 +307,12 @@ describe Notifier, type: :mailer do
         expect(comment_mail["From"].to_s).to eq("\"#{pod_name} (#{eve.name})\" <#{AppConfig.mail.sender_address}>")
       end
 
+      it "FROM: removes emojis from sender's name" do
+        eve.person.profile.update!(first_name: "1️⃣2️3️⃣ Numbers 123", last_name: "👍✅👍🏻Emojis😀😇❄️")
+        expect(comment_mail["From"].to_s)
+          .to eq("\"#{pod_name} (Numbers 123 Emojis)\" <#{AppConfig.mail.sender_address}>")
+      end
+
       it "SUBJECT: has a snippet of the post contents, without markdown and without newlines" do
         expect(comment_mail.subject).to eq("Re: Headline")
       end
@@ -390,6 +401,11 @@ describe Notifier, type: :mailer do
           expect(mail["From"].to_s).to eq("\"#{pod_name} (#{bob.name})\" <#{AppConfig.mail.sender_address}>")
         end
 
+        it "FROM: removes emojis from sender's name" do
+          bob.person.profile.update!(first_name: "1️⃣2️3️⃣ Numbers 123", last_name: "👍✅👍🏻Emojis😀😇❄️")
+          expect(mail["From"].to_s).to eq("\"#{pod_name} (Numbers 123 Emojis)\" <#{AppConfig.mail.sender_address}>")
+        end
+
         it "SUBJECT: does not show the limited post" do
           expect(mail.subject).not_to include("Limited headline")
         end
@@ -415,6 +431,11 @@ describe Notifier, type: :mailer do
           expect(mail["From"].to_s).to eq("\"#{pod_name} (#{bob.name})\" <#{AppConfig.mail.sender_address}>")
         end
 
+        it "FROM: removes emojis from sender's name" do
+          bob.person.profile.update!(first_name: "1️⃣2️3️⃣ Numbers 123", last_name: "👍✅👍🏻Emojis😀😇❄️")
+          expect(mail["From"].to_s).to eq("\"#{pod_name} (Numbers 123 Emojis)\" <#{AppConfig.mail.sender_address}>")
+        end
+
         it "SUBJECT: does not show the limited post" do
           expect(mail.subject).not_to include("Limited headline")
         end
@@ -446,6 +467,11 @@ describe Notifier, type: :mailer do
         expect(mail["From"].to_s).to eq("\"#{pod_name} (#{bob.name})\" <#{AppConfig.mail.sender_address}>")
       end
 
+      it "FROM: removes emojis from sender's name" do
+        bob.person.profile.update!(first_name: "1️⃣2️3️⃣ Numbers 123", last_name: "👍✅👍🏻Emojis😀😇❄️")
+        expect(mail["From"].to_s).to eq("\"#{pod_name} (Numbers 123 Emojis)\" <#{AppConfig.mail.sender_address}>")
+      end
+
       it "SUBJECT: does not show the limited post" do
         expect(mail.subject).not_to include("Limited headline")
       end