Added option and test

plugin/bullets.vim

@@ -61,6 +61,11 @@ end
 if !exists('g:bullets_max_alpha_characters')
   let g:bullets_max_alpha_characters = 2
 end
+
+if !exists('g:bullets_enable_roman_list')
+  let g:bullets_enable_roman_list = 1
+end
+
 " calculate the decimal equivalent to the last alphabetical list item
 let s:power = g:bullets_max_alpha_characters
 let s:abc_max = -1
@@ -166,12 +171,16 @@ endfun
 
 
 fun! s:match_roman_list_item(input_text)
+  if !g:bullets_enable_roman_list
+    return {}
+  endif
+
   let l:rom_bullet_regex  = join([
         \ '\v\C',
         \ '^(',
         \   '(\s*)',
         \   '(',
-        \     'M{0,4}%(CM|CD|D?C{0,3})%(XC|XL|L?X{0,3})%(IX|IV|V?I{0,3})',
+        \     'M{0,4}%(CM|CD|D?C{0,3})%(XC|XL|L?X{0,3})%(IX|IV|V?I{0,3})',A
         \     '|',
         \     'm{0,4}%(cm|cd|d?c{0,3})%(xc|xl|l?x{0,3})%(ix|iv|v?i{0,3})',
         \   ')',

spec/bullets_spec.rb

@@ -293,6 +293,39 @@
           -
         TEXT
       end
+
+      it 'toggles roman numeral bullets with g:bullets_enable_roman_list' do
+        filename = "#{SecureRandom.hex(6)}.txt"
+        write_file(filename, <<-TEXT)
+          # Hello there
+          i. this is the first bullet
+        TEXT
+
+        vim.command 'let g:bullets_enable_roman_list = 1'
+        vim.edit filename
+        vim.type 'GA'
+        vim.feedkeys '\<cr>'
+        vim.type 'second bullet'
+        vim.feedkeys '\<cr>'
+        vim.type 'third bullet'
+        vim.feedkeys '\<cr>'
+        vim.command 'let g:bullets_enable_roman_list = 0'
+        vim.type 'fourth bullet'
+        vim.feedkeys '\<cr>'
+        vim.type 'fifth bullet'
+        vim.write
+
+        file_contents = IO.read(filename)
+
+        expect(file_contents).to eq normalize_string_indent(<<-TEXT)
+          # Hello there
+          i. this is the first bullet
+          ii. second bullet
+          iii. third bullet
+          fourth bullet
+          fifth bullet\n
+        TEXT
+      end
     end
   end
 end