Display "asciicast:<id>" as a title for title-less asciicasts

app/decorators/asciicast_decorator.rb

@@ -23,13 +23,7 @@ class AsciicastDecorator < ApplicationDecorator
   end
 
   def title
-    if model.title.present?
-      model.title
-    elsif command.present?
-      "$ #{command}"
-    else
-      "##{id}"
-    end
+    model.title.presence || model.command.presence || "asciicast:#{id}"
   end
 
   def thumbnail(width = THUMBNAIL_WIDTH, height = THUMBNAIL_HEIGHT)

spec/decorators/asciicast_decorator_spec.rb

@@ -133,7 +133,7 @@ describe AsciicastDecorator do
         asciicast.command = 'cmd'
       end
 
-      it { should == '$ cmd' }
+      it { should == 'cmd' }
     end
 
     context 'when no title nor command is present' do
@@ -144,7 +144,7 @@ describe AsciicastDecorator do
       end
 
       it 'should be in the form of "#<id>"' do
-        should == "##{asciicast.id}"
+        should == "asciicast:#{asciicast.id}"
       end
     end
   end