See #828, #757, #731, #750. Fix Riot.js support,

add support to Pretty diff beautifier

examples/nested-jsbeautifyrc/riotjs/expected/test.tag

@@ -7,15 +7,25 @@
   <script>
     this.message = 'Hello, Riot!'
     this.techs = [
-      { name: 'HTML' },
-      { name: 'JavaScript' },
-      { name: 'CSS' }
+      {
+        name: 'HTML'
+      }, {
+        name: 'JavaScript'
+      }, {
+        name: 'CSS'
+      }
     ]
   </script>
 
   <style scoped>
-    :scope { font-size: 2rem }
-    h3 { color: #444 }
-    ul { color: #999 }
+    :scope {
+      font-size: 2rem;
+    }
+    h3 {
+      color: #444;
+    }
+    ul {
+      color: #999;
+    }
   </style>
 </sample>

src/beautifiers/prettydiff.coffee

@@ -54,6 +54,7 @@ module.exports = class PrettyDiff extends Beautifier
     LESS: true
     Swig: true
     Visualforce: true
+    "Riot.js": true
   }
 
   beautify: (text, language, options) ->
@@ -73,7 +74,7 @@ module.exports = class PrettyDiff extends Beautifier
           lang = "ejs"
         when "ERB"
           lang = "html_ruby"
-        when "Handlebars", "Mustache", "Spacebars", "Swig"
+        when "Handlebars", "Mustache", "Spacebars", "Swig", "Riot.js"
           lang = "handlebars"
         when "SGML"
           lang = "markup"