Added 'comment=num' option to limit comments up to particular depth level

README.md

@@ -51,7 +51,7 @@ internal function, but set different options by default:
 
 * name (string) -- name; triggers full serialization with self-ref section
 * indent (string) -- indentation; triggers long multi-line output
-* comment (true/False) -- provide stringified value in a comment
+* comment (true/False/maxlevel) -- provide stringified value in a comment (up to maxlevel of depth)
 * sortkeys (true/False) -- sort keys
 * sparse (true/False) -- force sparse encoding (no nil filling based on #t)
 * compact (true/False) -- remove spaces
@@ -128,22 +128,27 @@ See LICENSE file.
 
 ## History
 
+Jun 17 2012 v0.15
+  - Added `ignore` option to allow ignoring table values.
+  - Added `comment=num` option to set the max level up to which add comments.
+  - Changed all comments (except math.huge) to be controlled by `comment` option.
+
 Jun 13 2012 v0.14
   - Fixed an issue with string keys with numeric values `['3']` getting mixed
     with real numeric keys (only with `sortkeys` option set to `true`).
   - Fixed an issue with negative and real value numeric keys being misplaced.
 
 Jun 13 2012 v0.13
-  - Added maxlevel option.
+  - Added `maxlevel` option.
   - Fixed key sorting such that `true` and `'true'` are always sorted in
     the same order (for a more stable output).
   - Removed addresses from names of temporary variables (for stable output).
 
 Jun 12 2012 v0.12
   - Added options to configure serialization process.
-  - Added 'goto' to the list of keywords for Lua 5.2.
+  - Added `goto` to the list of keywords for Lua 5.2.
   - Changed interface to dump/line/block methods.
-  - Changed 'math.huge' to 1/0 for better portability.
+  - Changed `math.huge` to 1/0 for better portability.
   - Replaced \010 with \n for better readability.
 
 Jun 03 2012 v0.10

src/serpent.lua

@@ -1,4 +1,4 @@
-local n, v = "serpent", 0.14 -- (C) 2012 Paul Kulchenko; MIT License
+local n, v = "serpent", 0.15 -- (C) 2012 Paul Kulchenko; MIT License
 local c, d = "Paul Kulchenko", "Serializer and pretty printer of Lua data types"
 local snum = {[tostring(1/0)]='1/0 --[[math.huge]]',[tostring(-1/0)]='-1/0 --[[-math.huge]]',[tostring(0/0)]='0/0'}
 local badtype = {thread = true, userdata = true}
@@ -14,15 +14,16 @@ local function s(t, opts)
   local name, indent, fatal = opts.name, opts.indent, opts.fatal
   local sparse, custom, huge = opts.sparse, opts.custom, not opts.nohuge
   local space, maxl = (opts.compact and '' or ' '), (opts.maxlevel or math.huge)
+  local comm = opts.comment and (tonumber(opts.comment) or math.huge)
   local seen, sref, syms, symn = {}, {}, {}, 0
   local function gensym(val) return tostring(val):gsub("[^%w]",""):gsub("(%d%w+)",
     function(s) if not syms[s] then symn = symn+1; syms[s] = symn end return syms[s] end) end
   local function safestr(s) return type(s) == "number" and (huge and snum[tostring(s)] or s)
     or type(s) ~= "string" and tostring(s) -- escape NEWLINE/010 and EOF/026
     or ("%q"):format(s):gsub("\010","n"):gsub("\026","\\026") end
-  local function comment(s) return opts.comment and ' --[['..tostring(s)..']]' or '' end
-  local function globerr(s) return globals[s] and globals[s]..comment(s) or not fatal
-    and safestr(tostring(s))..' --[[err]]' or error("Can't serialize "..tostring(s)) end
+  local function comment(s,l) return comm and (l or 0) < comm and ' --[['..tostring(s)..']]' or '' end
+  local function globerr(s,l) return globals[s] and globals[s]..comment(s,l) or not fatal
+    and safestr(tostring(s))..comment('err',l) or error("Can't serialize "..tostring(s)) end
   local function safename(path, name) -- generates foo.bar, foo[3], or foo['b a r']
     local n = name == nil and '' or name
     local plain = type(n) == "string" and n:match("^[%l%u_][%w_]*$") and not keyword[n]
@@ -42,18 +43,18 @@ local function s(t, opts)
       (name ~= nil and sname..space..'='..space or '')
     if seen[t] then
       table.insert(sref, spath..space..'='..space..seen[t])
-      return tag..'nil --[[ref]]'
-    elseif badtype[ttype] then return tag..globerr(t)
+      return tag..'nil'..comment('ref', level)
+    elseif badtype[ttype] then return tag..globerr(t, level)
     elseif ttype == 'function' then
       seen[t] = spath
       local ok, res = pcall(string.dump, t)
-      local func = ok and (opts.nocode and "function()error('dummy')end" or
-        "loadstring("..safestr(res)..",'@serialized')"..comment(t))
-      return tag..(func or globerr(t))
+      local func = ok and ((opts.nocode and "function() end" or
+        "loadstring("..safestr(res)..",'@serialized')")..comment(t, level))
+      return tag..(func or globerr(t, level))
     elseif ttype == "table" then
-      if level >= maxl then return tag..'{}'..comment('max') end
+      if level >= maxl then return tag..'{}'..comment('max', level) end
       seen[t] = spath
-      if next(t) == nil then return tag..'{}'..comment(t) end -- table empty
+      if next(t) == nil then return tag..'{}'..comment(t, level) end -- table empty
       local maxn, o, out = #t, {}, {}
       for key = 1, maxn do table.insert(o, key) end
       for key in pairs(t) do if not o[key] then table.insert(o, key) end end
@@ -68,7 +69,7 @@ local function s(t, opts)
           table.insert(sref, seen[t]..'['..(seen[key] or globals[key] or gensym(key))
             ..']'..space..'='..space..(seen[value] or val2str(value,nil,indent)))
         else
-          if badtype[ktype] then plainindex, key = true, '['..globerr(key)..']' end
+          if badtype[ktype] then plainindex, key = true, '['..globerr(key, level+1)..']' end
           table.insert(out,val2str(value,key,indent,spath,plainindex,level+1))
         end
       end
@@ -76,7 +77,7 @@ local function s(t, opts)
       local head = indent and '{\n'..prefix..indent or '{'
       local body = table.concat(out, ','..(indent and '\n'..prefix..indent or space))
       local tail = indent and "\n"..prefix..'}' or '}'
-      return (custom and custom(tag,head,body,tail) or tag..head..body..tail)..comment(t)
+      return (custom and custom(tag,head,body,tail) or tag..head..body..tail)..comment(t, level)
     else return tag..safestr(t) end -- handle all other types
   end
   local sepr = indent and "\n" or ";"..space

t/test.lua

@@ -57,8 +57,7 @@ assert(_a.list[4] == 'f', "specific table element preserves its value: failed")
 assert(_a.ignore == nil, "ignored table not serialized: failed")
 
 -- test without sparsness to check the number of elements in the list with nil
-_a = loadstring(serpent.dump(a, {sparse = false, nocode = true}))()
-assert(pcall(function() _a.z() end) == false, "nocode replaces functions with dummy errors: failed")
+_a = loadstring(serpent.dump(a, {sparse = false}))()
 assert(#(_a.list) == #(a.list), "size of array part stays the same: failed")
 
 local diffable = {sortkeys = true, comment = false, nocode = true, indent = ' '}
@@ -69,3 +68,13 @@ assert(serpent.block(a, diffable) == serpent.block(_a, diffable),
 _a = loadstring(serpent.dump(a, {sparse = false, nocode = true, maxlevel = 1}))()
 assert(#(_a.list) == 0, "nested table 1 is empty with maxlevel=1: failed")
 assert(#(_a[true]) == 0, "nested table 2 is empty with maxlevel=1: failed")
+
+-- test comment level
+local dump = serpent.block(a, {comment = 1, nocode = true})
+assert(dump:find(tostring(a)), "first level comment is present with comment=1: failed")
+assert(not dump:find(tostring(a.list)), "second level comment is not present with comment=1: failed")
+assert(dump:find("function%(%) end"), "nocode replaces functions with an empty body: failed")
+
+assert(serpent.line(nil) == 'nil', "nil value serialized as 'nil': failed")
+assert(serpent.line(123) == '123', "numeric value serialized as number: failed")
+assert(serpent.line("123") == '"123"', "string value serialized as string: failed")