Highlight code in markdown and git files

1 files changed, 20 insertions, 0 deletions

diff --git a/lib/render.js b/lib/render.js
index ee8ce01..e9d4889 100644
--- a/lib/render.js
+++ b/lib/render.js
@@ -10,6 +10,7 @@ var qs = require('querystring')
 var u = require('./util')
 var multicb = require('multicb')
 var RenderMsg = require('./render-msg')
+var Highlight = require('highlight.js')
 
 module.exports = Render
 
@@ -83,6 +84,7 @@ function Render(app, opts) {
     smartypants: false,
     emoji: lexerRenderEmoji,
     renderer: new MdRenderer(this),
+    highlight: this.highlight.bind(this),
   }
 }
 
@@ -368,3 +370,21 @@ Render.prototype.npmAuthorLink = function (author) {
     secondaryLink ? [' (', secondaryLink, ')'] : ''
   ]
 }
+
+// auto-highlight is slow
+var useAutoHighlight = false
+
+Render.prototype.highlight = function (code, lang) {
+  if (code.length > 100000) return u.escapeHTML(code)
+  if (!lang && /^#!\/bin\/[^\/]*sh$/m.test(code)) lang = 'sh'
+  try {
+    return lang
+      ? Highlight.highlight(lang, code).value
+      : useAutoHighlight
+      ? Highlight.highlightAuto(code).value
+      : u.escapeHTML(code)
+  } catch(e) {
+    if (!/^Unknown language/.test(e.message)) console.trace(e)
+    return u.escapeHTML(code)
+  }
+}