FIX: Support unicode replacements with multiple codepoints

app/models/emoji.rb

@@ -131,17 +131,22 @@ class Emoji
     "#{Discourse.base_uri}/uploads/#{db}/_emoji"
   end
 
+  def self.replacement_code(code)
+    hexes = code.split('-').map(&:hex)
+
+    # Don't replace digits, letters and some symbols
+    return hexes.pack("U" * hexes.size) if hexes[0] > 255
+  end
+
   def self.unicode_replacements
     return @unicode_replacements if @unicode_replacements
 
 
     @unicode_replacements = {}
     db['emojis'].each do |e|
-      hex = e['code'].hex
-      # Don't replace digits, letters and some symbols
-      if hex > 255 && e['name'] != 'tm'
-        @unicode_replacements[[hex].pack('U')] = e['name']
-      end
+      next if e['name'] == 'tm'
+      code = replacement_code(e['code'])
+      @unicode_replacements[code] = e['name'] if code
     end
 
     @unicode_replacements["\u{2639}"] = 'frowning'

spec/models/emoji_spec.rb

@@ -0,0 +1,18 @@
+require 'rails_helper'
+
+describe Emoji do
+
+  it "returns the correct codepoints" do
+    expect(Emoji.replacement_code('1f47d').codepoints).to eq([128125])
+  end
+
+  it "handles multiple codepoints" do
+    expect(Emoji.replacement_code('1f1e9-1f1ea').codepoints).to eq([127465, 127466])
+  end
+
+  it "returns nil for weird cases" do
+    expect(Emoji.replacement_code('32')).to be_nil
+    expect(Emoji.replacement_code('robin')).to be_nil
+  end
+
+end