Quiz data fixup fix 2020-12-08

closes LS-1689
flag=none

test plan:
  - it doesn't delete the answers in the adelaide Recursion 2 question
  - it replaces raw latex with eq images in the templeu question text
    in the last question
  - in the bridgeport quiz, there's a question that includes the statement
    "Type an exact answer by using the Equation Editor, if needed."
    That text should not be typeset like it's math
  - other broken quiz fixes still work

Change-Id: I0a95f9a84ec5c034514609f5ce6c639e0b13d3b1
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/254678
Tested-by: Service Cloud Jenkins <svc.cloudjenkins@instructure.com>
Reviewed-by: Nate Armstrong <narmstrong@instructure.com>
QA-Review: Nate Armstrong <narmstrong@instructure.com>
Product-Review: Ed Schiebel <eschiebel@instructure.com>

lib/quiz_math_data_fixup.rb

@@ -66,6 +66,9 @@ module QuizMathDataFixup
     %i[neutral_comments_html correct_comments_html incorrect_comments_html].each do |key|
       data[key] = fixup_html(data[key]) if data[key].present?
     end
+    
+    data[:question_text] = fixup_html(data[:question_text]) if data[:question_text].present?
+
     data[:answers].each_with_index do |answer, index|
       %i[html comments_html].each do |key|
         # if there's html, the text field is used as the title attribute/tooltip
@@ -83,9 +86,9 @@ module QuizMathDataFixup
     data
   end
 
-  def fixup_html(html)
-    return html unless html
-    html = Nokogiri::HTML::DocumentFragment.parse(html)
+  def fixup_html(html_str)
+    return html_str unless html_str
+    html = Nokogiri::HTML::DocumentFragment.parse(html_str)
     if html.children.length == 1 && html.children[0].node_type == Nokogiri::XML::Node::TEXT_NODE
       # look for an equation_images URL in the text and extract the latex
       m = %r{equation_images\/([^\s]+)}.match(html.content)
@@ -121,6 +124,11 @@ module QuizMathDataFixup
         mjnodes.each(&:remove)
       end
       if (latex.content.length > 0)
+        if latex.content !~ /^(:?\\\(|\$\$).+(:?\\\)|\$\$)$/
+          # the content is not delimineted latex,
+          # emove math_equation_latex from the class then leave it alone
+          latex.attribute('class').value = latex.attribute('class').value.sub('math_equation_latex', '').strip
+        else
           code = latex.content.gsub(/(^\\\(|\\\)$)/, '')
           escaped = URI.escape(URI.escape(code))
           latex.replace(
@@ -128,9 +136,10 @@ module QuizMathDataFixup
               code
             }' title='#{code}' data-equation-content='#{code}'/>"
           )
+        end
       elsif mml
         latex.replace(
-          "<math xmlns='http://www.w3.org/1998/Math/MathML' class='math_equation_mml'>#{mml}</math>"
+          "<span class='math_equation_mml'><math xmlns='http://www.w3.org/1998/Math/MathML'>#{mml}</math></span>"
         )
       end
     end
@@ -138,6 +147,7 @@ module QuizMathDataFixup
     html.search('[id^="MathJax"]').each(&:remove)
     html.search('span.hidden-readable').each(&:remove)
 
+    return html_str if html.content.length == 0 && html.search('img.equation_image').length == 0
     html.to_s
   end