FIX: details tags broke excerpts

lib/excerpt_parser.rb

@@ -18,6 +18,7 @@ class ExcerptParser < Nokogiri::XML::SAX::Document
     @keep_onebox_source = options[:keep_onebox_source] == true
     @remap_emoji = options[:remap_emoji] == true
     @start_excerpt = false
+    @summary_contents = ""
   end
 
   def self.get_excerpt(html, length, options)
@@ -108,6 +109,10 @@ class ExcerptParser < Nokogiri::XML::SAX::Document
           include_tag("span", attributes)
           @in_spoiler = true
         end
+    when "details"
+      @in_details = true
+    when "summary"
+      @in_summary = true
     end
   end
 
@@ -126,6 +131,14 @@ class ExcerptParser < Nokogiri::XML::SAX::Document
       end
     when "aside"
       @in_quote = false
+    when "details"
+      @in_details = false
+    when "summary"
+      @in_summary = false
+      if @summary_contents.present?
+        @excerpt << "<details class='disabled'><summary>#{@summary_contents[0..@length]}</summary></details>"
+      end
+      @summary_contents = ""
     when "div", "span"
       throw :done if @start_excerpt
       characters("</span>", false, false, false) if @in_spoiler
@@ -135,8 +148,15 @@ class ExcerptParser < Nokogiri::XML::SAX::Document
 
   def characters(string, truncate = true, count_it = true, encode = true)
     return if @in_quote
+
     # we call length on this so might as well ensure we have a string
     string = string.to_s
+    if @in_details
+      if @in_summary
+        @summary_contents << string
+      end
+      return
+    end
 
     encode = encode ? lambda { |s| ERB::Util.html_escape(s) } : lambda { |s| s }
     if count_it && @current_length + string.length > @length