Add option to use WARNING in alerts

This is a drop-in replacement of CAUTION, and they can
be used interchangeably.

1 files changed, 3 insertions, 1 deletions

diff --git a/lib/filters/admonition.rb b/lib/filters/admonition.rb
index 0cb288fa..8952f7cf 100644
--- a/lib/filters/admonition.rb
+++ b/lib/filters/admonition.rb
@@ -6,6 +6,7 @@ class AdmonitionFilter < Nanoc::Filter
     'tip' => 'success',
     'note' => 'info',
     'caution' => 'warning',
+    'warning' => 'warning',
     'danger' => 'danger'
   }.freeze
 
@@ -13,6 +14,7 @@ class AdmonitionFilter < Nanoc::Filter
     'tip' => 'bulb',
     'note' => 'information-o',
     'caution' => 'warning',
+    'warning' => 'warning',
     'danger' => 'warning'
   }.freeze
 
@@ -22,7 +24,7 @@ class AdmonitionFilter < Nanoc::Filter
     doc = Nokogiri::HTML.fragment(content.dup)
     doc.css('p').each do |para|
       content = para.inner_html
-      match = content.match(/\A(?<type>TIP|NOTE|CAUTION|DANGER):\s?(?<content>.*)\Z/m)
+      match = content.match(/\A(?<type>TIP|NOTE|CAUTION|WARNING|DANGER):\s?(?<content>.*)\Z/m)
       next unless match
 
       new_content = generate(match[:type].downcase, match[:content])