Use String#include? over String#=~

Warming up --------------------------------------
    no body include?   114.533k i/100ms
      no body regexp    40.573k i/100ms
Calculating -------------------------------------
    no body include?      2.443M (± 3.6%) i/s -     12.255M
      no body regexp    507.675k (± 2.3%) i/s -      2.556M

Comparison:
    no body include?:  2442987.7 i/s
      no body regexp:   507675.5 i/s - 4.81x slower

Warming up --------------------------------------
  with body include?   114.182k i/100ms
    with body regexp    40.746k i/100ms
Calculating -------------------------------------
  with body include?      2.334M (± 7.4%) i/s -     11.647M
    with body regexp    450.995k (± 5.8%) i/s -      2.282M

Comparison:
  with body include?:  2334117.9 i/s
    with body regexp:   450995.3 i/s - 5.18x slower

Code: jekyll/jekyll@c28a17d

Author: parkr

lib/jekyll-mentions.rb

@@ -4,14 +4,16 @@
 module Jekyll
   class Mentions
     GITHUB_DOT_COM = "https://github.com".freeze
+    BODY_START_TAG = "<body".freeze
+
 
     InvalidJekyllMentionConfig = Class.new(Jekyll::Errors::FatalException)
 
     class << self
       def mentionify(doc)
         return unless doc.output.include?("@")
         src = mention_base(doc.site.config)
-        if doc.output =~ /<\s*body/
+        if doc.output.include? BODY_START_TAG
           parsed_doc    = Nokogiri::HTML::Document.parse(doc.output)
           body          = parsed_doc.at_css('body')
           body.children = filter_with_mention(src).call(body.inner_html)[:output].to_s