more correct babycode parsing

lib/babycode.lua

@@ -1,15 +1,5 @@
 local babycode = {}
 
-local _escape_html = function(text)
-  return text:gsub("[&<>\"']", {
-    ["&"] = "&amp;",
-    ["<"] = "&lt;",
-    [">"] = "&gt;",
-    ['"'] = "&quot;",
-    ["'"] = "&#39;"
-  })
-end
-
 ---renders babycode to html
 ---@param s string input babycode
 ---@param escape_html fun(s: string): string function that escapes html
@@ -21,7 +11,8 @@ function babycode.to_html(s, escape_html)
   local code_count = 0
   local text = s:gsub("%[code%](.-)%[/code%]", function(code)
     code_count = code_count + 1
-    code_blocks[code_count] = code
+    -- strip leading and trailing newlines, preserve others
+    code_blocks[code_count] = code:gsub("^%s*(.-)%s*$", "%1")
     return "\1CODE:"..code_count.."\1"
   end)
 
@@ -48,14 +39,14 @@ function babycode.to_html(s, escape_html)
     return url
   end)
 
+  -- normalize newlines, replace them with <br>
+  text = text:gsub("\r?\n\r?\n+", "<br>"):gsub("\r?\n", "<br>")
+
   -- replace code block placeholders back with their original contents
   text = text:gsub("\1CODE:(%d+)\1", function(n)
     return "<pre><code>"..code_blocks[tonumber(n)].."</code></pre>"
   end)
 
-  -- finally, normalize newlines replace them with <br>
-  text = text:gsub("\r?\n\r?\n+", "<br>"):gsub("\r?\n", "<br>")
-
   return text
 end