Render codespans properly in markdown (#1678)

* Explain test properly

* Add tests for codespan parsing

* Add codespan parsing logic

app/labor/markdown_parser.rb

@@ -120,10 +120,12 @@ class MarkdownParser
   end
 
   def escape_liquid_tags_in_codeblock(content)
-    # Escape BOTH codeblock and inline code
-    content.gsub(/`{3}.*?`{3}|`{1}.+?`{1}/m) do |codeblock|
-      if codeblock.include?("```")
+    # Escape codeblocks, code spans, and inline code
+    content.gsub(/`{3}.*?`{3}|`{2}.+?`{2}|`{1}.+?`{1}/m) do |codeblock|
+      if codeblock[0..2] == "```"
         "\n{% raw %}\n" + codeblock + "\n{% endraw %}\n"
+      elsif codeblock[0..1] == "``"
+        "{% raw %}" + codeblock + "{% endraw %}"
       else
         "{% raw %}" + codeblock + "{% endraw %}"
       end

spec/labor/markdown_parser_spec.rb

@@ -8,16 +8,31 @@ RSpec.describe MarkdownParser do
     described_class.new(raw_markdown).finalize
   end
 
-  it "works" do
+  it "renders plain text as-is" do
     expect(basic_parsed_markdown.finalize).to include(random_word)
   end
 
-  it "escape liquid tags in codeblock" do
+  it "escapes liquid tags in codeblock" do
     code_block = "```\n{% what %}\n```"
     expect(generate_and_parse_markdown(code_block)).to include("{% what %}")
   end
 
-  it "escape liquid tags in inline code" do
+  it "escapes liquid tags in code spans" do
+    code_span = "``{% what %}``"
+    expect(generate_and_parse_markdown(code_span)).to include("{% what %}")
+  end
+
+  it "renders double backtick code spans properly" do
+    code_span = "``#{random_word}``"
+    expect(generate_and_parse_markdown(code_span)).to include random_word
+  end
+
+  it "renders a double backtick codespan with a word wrapped in single backticks properly" do
+    code_span = "`` `#{random_word}` ``"
+    expect(generate_and_parse_markdown(code_span)).to include "`#{random_word}`"
+  end
+
+  it "escapes liquid tags in inline code" do
     inline_code = "`{% what %}`"
     expect(generate_and_parse_markdown(inline_code)).to include(inline_code[1..-2])
   end